KR20190031450A - Chip scale packaging light emitting device and manufacturing method of the same - Google Patents

Abstract

Disclosed are a chip scale package (CSP) LED device and a manufacturing method thereof. The CSP LED device comprises a flip-chip LED semiconductor die and a packaging structure, wherein the packaging structure includes a soft buffer layer, a photoluminescent structure and an encapsulant structure. The soft buffer layer includes a top portion formed on the flip-chip LED semiconductor die, and an end portion formed to cover an edge surface of the flip-chip LED semiconductor die, wherein the top portion has a convex surface, and the end portion has an extension surface smoothly being in contact with the convex surface. The photoluminescent structure is formed on the soft buffer layer to cover the convex surface and the extension surface of the soft buffer layer. The encapsulant structure, which has a hardness not lower than that of the buffer layer, is formed on the photoluminescent structure. Therefore, the CSP LED device has improved reliability and improved optical performance such as more constant correlated color temperature (CCT), more constant spatial color, and higher optical efficacy by improving adhesion strength between the flip-chip LED semiconductor die and the packaging structure.

Description

TECHNICAL FIELD [0001] The present invention relates to a chip scale package light emitting device,

The present invention relates to a light emitting diode (LED) device and a method of manufacturing the same. More particularly, the present invention relates to a chip scale package light emitting diode (LED) device and a flip chip LED semiconductor die (flip-chip LED semiconductor die).

LEDs are widely used in a variety of applications such as traffic lights, backlight units, general lighting, portable devices, and automotive lighting. Typically, an LED semiconductor die is disposed within a package structure, such as a lead frame, to form a package LED device. The LED semiconductor die may be further disposed to form a phosphor-converted white LED device and covered by a phosphorescent material such as a phosphor.

Recent developments in chip scale package (CSP) LED devices have attracted more attention due to their excellent benefits. As a general example, a white light CSP LED device typically consists of a phosphorescent structure that covers a blue light LED semiconductor die and a small chip scale sized LED semiconductor die. A blue LED semiconductor die is typically a flip chip LED that emits blue light at the top and four peripheral edge sides simultaneously. A phosphorescent structure is disposed to cover the LED semiconductor die to down-convert the wavelengths of the blue light emitted from the top surface as well as the four peripheral edge surfaces. After passing through the phosphorescent structure, a portion of the blue light is converted to a higher wavelength (lower energy) light and the light having a different wavelength spectrum is mixed at a later predetermined rate to generate the next target color temperature white light. To achieve the goal of uniformly converting blue light, the phosphorescent structure comprises the same thickness and the same distribution density of the phosphorescent material on the top and four peripheral edge faces, so to speak, the conformal coating layer ) Is preferably formed.

Compared to surface mount type (PLCC) LED devices, CSP light emitting devices exhibit the following advantages. (1) Since the bonding wire and the lead frame are not used, the material cost is considerably reduced. (2) The thermal resistance between the LED semiconductor die and a mounting substrate, typically a printed circuit board (PCB), is further reduced without the use of a lead frame in between. Therefore, at the same drive current, the LED operating temperature is lower. In other words, less electrical energy may be consumed to obtain more optical power for CSP LED devices. (3) Lower operating temperatures provide higher LED semiconductor quantum efficiency for CSP LED devices. (4) a much smaller form factor of the light source provides more design flexibility for module-level LED fixtures. (5) A CSP LED device having a small light emitting area is more similar to a point source, thereby making it easier to design a secondary optics. Small CSP LED devices can be designed to generate small-etendue light with higher light intensity that is specific to some projected optical applications such as automotive headlamps.

However, even though the CSP LED device has many advantages, the adhesion between the phosphorescent structure and the LED semiconductor die is relatively weak compared to the adhesion of the PLCC type LED device. In the case of CSP LED devices, the lead frame or submount can be omitted so that the phosphorescent structure comes into contact with the LED semiconductor die primarily or only with the surface without the additional surface contacting the leadframe or submount. Therefore, the contact area of the phosphorescent structure is relatively limited only to the LED semiconductor die surface without further contact to the submount area. The limited contact area generally weakens the contact force between the phosphorescent structure and the LED semiconductor die. Furthermore, the coefficient of thermal expansion (CTE) of a phosphorescent structured material (typically composed of an organic resin material) is generally much greater than the coefficient of thermal expansion of an LED semiconductor die material (typically composed of inorganic materials). The apparent CTE mismatch during thermal cycling while operating the CSP LED device will cause internal stress between the interfaces of these two materials. Due to the weak adhesion to the LED semiconductor die, the phosphorescent structure is easily delaminated and tends to be peeled off from the LED semiconductor die. The phosphorescent delamination is one of the major CSP failure mechanisms in the operation of CSP type LED devices. This disadvantage affects the reliability of CSP LED devices and is a practical limitation to CSP LED applications.

Another problem with CSP type LED devices is low color uniformity. There are two main mechanisms for producing low color uniformity. 1. Unequal mechanical dimensions of the phosphorescent structure and 2. Non-adjustable phosphor particle distribution in the phosphorescent structure from one device to another. In a relative manufacturing process for manufacturing a CSP type LED device, first, the phosphor particles are mixed in a binder resin material to form a phosphor slurry; The phosphor slurry is then placed on the LED semiconductor die to form a phosphorescent structure using methods such as molding, screen printing, spraying, and the like. It will be appreciated that when the phosphor slurry is used to form a phosphorescent structure, precise regulation of the geometric dimensions of the phosphorescent structure is desirable to achieve the required cross-color temperature (CCT) of the CSP LED device. However, it is very difficult to accurately and uniformly adjust the size of each phosphorescent structure in a mass production process. Even when the geometrical dimensions of the phosphorescent structure are precisely controlled in mass production, there is no mechanism for controlling the particle distribution of the fluorescent material inside the phosphorescent structure. In fact, the control of the distribution of phosphor materials is one of the most important factors in determining optical properties such as CCT of CSP LED devices. It is therefore highly desirable to achieve the conformal coating of the phosphor particles covering the top and four edge surfaces of the LED semiconductor die to form a phosphorescent structure to achieve uniform photoconversion characteristics of the CSP LED device in a high volume manufacturing process .

Specifically, several manufacturing steps in a mass production process were able to generate low color uniformity for CSP type LED devices resulting in poor manufacturing yields. For example, when the phosphorescent structure of a CSP LED device is formed from a phosphor material through a molding (or screen printing) process, the preceding step involves forming a plurality of LED semiconductors (or semiconductors) And arranging the die. However, the incorrect arrangement to form an array of LED semiconductor dies will form an irregular thickness of the top and edge sides of the phosphorescent structure. In addition, a common singulation process is utilized to subsequently separate the array of CSP LED devices after the array of phosphorescent structures is formed. Imperfect positioning of the dicing saw will make the thickness of the edge of the phosphorescent structure from one CSP LED device to another CSP LED device uneven. In addition, the particle distribution of the phosphor material in the phosphor slurry can not be controlled, thereby hindering the color uniformity. As a result, light passing through the non-uniform phosphorescent structure of the LED device will produce low color uniformity. Even for each CSP LED device, low spatial color uniformity for different viewing angles is common due to the varying phosphor translational distance of the phosphorescent structure that blue light will experience. Low color uniformity results in poor production in mass production.

Alternatively, a spray coating process is another manufacturing process for forming a phosphorescent structure with a conformally coated phosphor layer. Problems caused by incorrect alignment of LED semiconductor dies can be mitigated using a spray process rather than a molding or screen printing process. However, another problem arises when manufacturing a phosphorescent structure using a spray process. It can be seen that it is difficult to obtain the phosphor particles beside the vertical edge side of the LED semiconductor die because the gravitational effect precipitates the phosphor particles during manufacturing. This gravitational effect will make it difficult to form a substantially continuous layer of phosphor materials on the edge sides of the LED semiconductor die. Even though a transparent and continuous resin layer can be formed on the edge surface of the LED semiconductor die, the phosphor particle layer in the resin material is positionally discontinuous. That is, the fabrication of a phosphorescent structure utilizing a spray process will form a substantially larger, optically transparent structure of "voids ". Therefore, the blue light emitted from the LED semiconductor die leaks more from the void and the blue light passes directly through the phosphor material with less opportunity for wavelength conversion. You will find that the voids found on the four vertical edge faces will generally cause more of the blue light to leak from the edge of the CSP LED device. Therefore, the blue ring is generated for CSP LED devices manufactured using this spray process. In other words, the spray process can not generally be used to achieve a phosphorescent structure that is the preferred conformal coating of the phosphor powder. Furthermore, if the spray structure is used to form a thin phosphorescent structure, the top of the phosphorescent structure directly above the top of the LED semiconductor die tends to have a paricle aggregation effect. This agglomerated phosphor powder distribution will generate substantially large optical voids consisting of an optically transparent resin material without many phosphor materials mixed therein. This phosphor material aggregation effect is a major cause for the undesirable " blue light spots " Blue light leaking from substantially large and substantially transparent voids can generate strong intensity at the position of blue light, resulting in low spatial color uniformity and also a risk factor of blue light harmful to the human eye. Other side effects due to phosphor powder aggregation are low color uniformity, poor throughput and low phosphor wavelength conversion efficiency.

Another issue encountered when using CSP type LED devices is device reliability. One of the key technical features of the CSP type LED device is that it does not include a submount substrate or leadframe and that it directly exposes an underneath bonding pad in the LED semiconductor die. Without the submount substrate, the phosphorescent structure of the CSP LED device is also exposed at the bottom. A reflow soldering processor is usually used when a CSP LED device is bonded onto an application substrate such as a PCB. During the reflow soldering process, the soldering flux is generally used to improve the bond quality between the CSP LED device and the substrate. However, the additives contained in the soldering plus tend to react with the benzene structures commonly found in silicon binder materials. However, the phosphorescent structure can be composed of a silicone resin material. This chemical reaction will form a harmful dark layer on the lower surface of the phosphorescent structure. Therefore, optical efficiency and reliability of CSP LED devices will deteriorate.

Therefore, providing a mass-production solution provides improved interface adhesion between the LED semiconductor die and the phosphorescent structure, enhances spatial color uniformity and CCT binning consistency, increases optical efficiency and prevents formation of a negative dark layer on the bottom of the phosphorescent structure, It is necessary to solve the above-mentioned problem of the LED device.

An object of some embodiments of the present invention is to provide a CSP LED device with a small irradiance area, improved reliability, spatial color uniformity, CCT binning consistency, optical efficiency and reduced thermal resistance.

Another object of an embodiment of the present invention is to provide a manufacturing method for manufacturing an open CSP LED device.

In order to realize the object, a CSP LED device including an LED semiconductor die and a package structure and including a soft buffer layer, a photoluminescent structure, and an encapsulant structure is disclosed according to some embodiments of the present invention. The LED semiconductor die is a flip chip LED semiconductor including top, bottom, corner, and electrode sets. The corner surface is formed and extends between the upper surface and the lower surface, and the electrode set is disposed on the lower surface. The soft buffer layer may be made of a polymeric resin material of some embodiments or may include a polymeric resin material. The soft buffer layer includes an upper portion formed or disposed on the upper surface of the LED semiconductor die and an edge portion formed to cover the corner surface of the LED semiconductor die. The upper portion shows a convex surface and the end portion includes an extending surface that smoothly abuts the convex surface. The phosphorescent structure is formed on the soft buffer layer covering the convex surface and the extending surface. The phosphorescent structure includes a resin binder material such as silicon, epoxy, rubber and the like and a phosphorescent material dispersed in the binder material. An encapsulant structure that can be made of a polymeric material whose hardness is not less than the hardness of the soft buffer layer is formed on the phosphorescent structure.

To achieve this object, a method of manufacturing a CSP LED device of some embodiments includes arranging a plurality of LED semiconductor dies on a release film to form an array of LED semiconductor dies, arranging an array of package structures connected over the array of LED semiconductor dies Forming a plurality of CSP LED devices, and singulating an array of package structures to form a plurality of CSP LED devices, wherein the release films can be removed before or after singulating the package structure.

The method of forming an array of package structures on an array of LED semiconductor dies further comprises the steps of: 1. forming a respective array of LED semiconductor dies, each soft buffer layer Wherein an upper portion of each LED semiconductor die is formed with an end portion of each soft buffer layer disposed on an upper surface of each LED semiconductor die and including an extension surface adjacent the upper convex surface to cover an edge surface of each LED semiconductor die; 2. A method of sequentially depositing a phosphorescent material and a polymeric material to form a phosphorescent structure by forming an array of phosphorescent structures on an array of soft buffer layers covering the convex surface and the extending surface; And 3. forming an array of encapsulation structures on the array of phosphorescent structures, wherein the hardness of the encapsulation structure is not less than the hardness of the soft buffer layer.

Thus, an improved CSP LED device according to some embodiments of the present invention provides at least the following advantages.

First, the CSP LED device according to some embodiments of the present invention has improved reliability during operation. In the case of a relative CSP LED device, the phosphorescent structure is formed in direct contact with the LED semiconductor die. It will be appreciated that the phosphorescent structure generally comprises a ceramic phosphor material in the form of a powder dispersed in a polymeric binder material. In general, however, the ceramic material will not form a chemical bond with the LED semiconductor die during the CSP manufacturing process, and thus the ceramic material has poor adhesion or bonding strength with the LED semiconductor die. The adhesion between the phosphorescent structure and the LED semiconductor die is mainly improved from the polymeric binder material. Thereby reducing the contact surface between the polymeric material and the surface of the LED semiconductor die when the phosphor powder is dispersed within the polymeric binder material. On the other hand, in the case of a CSP LED device according to some embodiments of the present invention, the soft buffer layer provides complete contact between the polymeric material and the LED semiconductor die. Therefore, the bonding strength between the phosphorescent structure and the LED semiconductor die can be significantly improved by introducing a soft buffer layer. Therefore, the soft buffer layer functions as an adhesion promoting layer.

In addition, the soft buffer layer can have a lower hardness to alleviate the internal stress induced by the CTE mismatch among the components in the CSP LED device. Therefore, the soft buffer layer also functions as a stress relaxation layer.

Therefore, the reliability of the CSP LED device according to some embodiments of the present invention is significantly improved during operation by preventing the package structure from being peeled off from the LED semiconductor die.

Second, the extended surface of the end of the soft buffer layer according to some embodiments of the present invention is a relatively gentle surface with a smaller slope of the slope. It is desirable for the extended surface of the soft buffer layer to have a smaller slope, so that the more abrupt vertical "step" of the edge surface of the LED semiconductor die is gentle. Without a soft, less inclined soft buffer layer, the phosphor material may tend to settle within the binder material due to gravity, so that a phosphor powder is provided on the edge of the LED semiconductor die to form a substantially continuous conformal phosphor coating layer It can be difficult. On the other hand, the soft buffer layer according to some embodiments of the present invention can significantly reduce the precipitation effect of the phosphor powder generated by gravity, so that a substantially continuous phosphor powder distribution is formed along the end of the soft buffer layer. In other words, an approximate conformal coating with a phosphor powder in a phosphorescent structure is realized according to some embodiments of the present invention. Therefore, the blue light leakage problem in the CSP LED device is solved. Thus, a CSP LED device according to some embodiments of the present invention exhibits improved spatial color uniformity and improved CCT binning consistency. The soft buffer layer therefore functions as a gentle layer to facilitate the formation of an approximate conformal coating of the phosphor powder in the phosphorescent structure.

Third, during the manufacturing process of the phosphorescent structure according to some embodiments of the CSP LED device of the present invention, the phosphorescent layer and the polymer resin layer are sequentially separated (for example, as disclosed in U. S. Patent No. US2010 / 0119839 . A very small phosphor layer can be formed by utilizing the disclosed phosphor deposition method. One advantage is that the phosphor particles are deposited as a uniform, thin, small conformal coating layer. And therefore substantially no "void" of phosphorescent material will be formed. As a result, the "blue light spot" and the blue light leakage problem are solved and the risk of blue light harmful to the human eye is also reduced. Another advantage is that once a phosphorescent structure with a high packing density is formed for a CSP LED device according to some embodiments of the present invention, the phosphorescent structure exhibits improved conversion efficiency and thus overall optical efficiency is improved.

Fourth, the manufacturing material for forming the soft buffer layer according to some embodiments of the CSP LED device of the present invention is selected from polymeric materials that do not contain a substance (e.g., benzene) that will chemically react with additives contained within the soldering flux . The reflow soldering process is typically used to bond CSP LED devices onto an application substrate such as a PCB. During the reflow soldering process, the soldering flux is typically utilized to improve the bond quality between the CSP LED device and the substrate. However, the additives contained within the soldering flux tend to react with the benzene found in the silicone binder material. When a soft buffer layer is made of a polymeric material containing benzene, this chemical reaction will form a harmful dark layer on the lower surface of the phosphorescent structure. However, if the soft buffer layer is composed of a benzene-free, substantially benzene-free polymeric material, it will block the phosphorescent structure from contacting the flux additive in a subsequent bonding process. Therefore, when the CSP LED device is bonded onto the substrate through the reflow soldering process, the additive contained in the soldering flux is substantially confined to the lower region of the CSP LED device by the soft buffer layer and is inhibited from reaching the phosphorescent structure. Thus, this deleterious chemical reaction is considerably prevented between (for example) the addition of the soldering flux and the benzene found in the silicon binder material used to make the phosphorescent structure. The dark layer, which is the result of this chemical reaction, is therefore significantly reduced and another type of degradation of the optical efficiency and reliability of the CSP LED device is avoided. In other words, the soft buffer layer also functions as an environmental barrier layer.

Other aspects and embodiments of the invention are contemplated. The foregoing summary and the following detailed description of the invention are not intended to limit the invention to any particular embodiment, but merely illustrate some embodiments of the invention.

FIGS. 1A, 1B and 1C are schematic cross-sectional views of a CSP LED device according to a first embodiment of the present invention, and FIGS. 1D and 1E are schematic views showing other forms of extension surfaces of a soft buffer layer according to another embodiment All.
2 is a schematic cross-sectional view of a CSP LED device according to a second embodiment of the present invention.
Figures 3A, 3B and 3C are schematic cross-sectional views of a CSP LED device according to a third embodiment of the present invention.
FIGS. 4A, 4B, 4C, 4D, 4E and 4F are schematic cross-sectional views illustrating steps of a fabrication method for forming a CSP LED device in accordance with some embodiments of the present invention.

[Justice]

The following definitions apply to some of the technical aspects described in connection with some embodiments of the present invention. Likewise, this definition can be expanded in accordance with the present description.

As used in this description, the singular terms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to a layer may include multiple layers unless the text clearly teaches.

As used in this description, the term "set" refers to a collection of one or more parts. Thus, for example, a layer set may comprise one layer or multiple layers. A set of parts may also refer to members of the set. A set of parts may be the same or different. In some instances, a set of components may share one or more common features.

As used in this description, the term "adjacent" Adjacent components may be released from each other or may be in substantial or direct contact with each other. In some cases, adjacent components may be interconnected or formed integrally with each other. In the description of some embodiments parts are provided "above" or "above" another part, as well as when there are one or more frayed parts located between the electronic part and the latter part, as well as when the electronic part is directly on the latter part For example, directly physically contacted). In the description of some embodiments, a part is provided beneath another part, as well as where one or more fused parts are located between the electronic part and the latter part, as well as where the electronic part is directly under the latter part ).

As used in this description, the terms "connect," " connected, " and "connection, " Connected components can be connected directly to each other or indirectly connected to each other as through another set of components.

As used in this description, the terms "approximately "," substantially "and" substantial "refer to a considerable degree or extent. When used in connection with an event or situation, the terms may refer to instances where an event or circumstance occurs precisely as well as instances where an event occurs, such as an event or situation describing typical tolerance levels of manufacturing operations described herein . For example, when used in connection with a numerical value, the terms are less than or equal to ± 5% of the numerical value, less than or equal to ± 4%, less than or equal to ± 3%, less than or equal to ± 2% Less than or equal to ± 1%, less than or equal to ± 0.5%, less than or equal to ± 0.1%, or less than or equal to ± 0.05%. have.

The term "efficiency" or "quantum efficiency, " as used in this description in connection with phosphorescence, refers to the ratio of the number of output photons to the number of input photons.

The term "size" as used in this description refers to a particular dimension. In the case of a spherical object (for example, a particle), the size of the object may indicate the dimension of the object. If the object is non-spherical, the size of the object may indicate the average of various orthogonal dimensions of the object. Thus, for example, the size of a spherical object may indicate the average of the major axis and minor axis of the object. If we refer to a set of objects as having a particular size, then the objects are considered to be able to contain a distribution of their magnitudes and sizes. Thus, the size of an object set such as that used in this description may indicate a typical size of a distribution of sizes, such as an average size, a medium size, or a maximum size.

1A shows a schematic cross-sectional view of a first embodiment of a CSP LED device according to the present invention. The CSP LED device 1A includes an LED semiconductor die 10 and a package structure 200 and the package structure 200 includes a soft buffer layer 20, a phosphorescent structure 30, and an encapsulation structure 40.

The LED semiconductor die 10 is a flip chip LED semiconductor including an upper surface 11, a lower surface 12, an edge surface 13, and an electrode set 14. The upper surface 11 and the lower surface 12 are formed substantially parallel and face each other on the opposite side. An edge surface 13 is formed to extend between the top surface 11 and the bottom surface 12 and to connect the rim of the top surface 11 with the rim of the bottom surface 12 and the outer rim of the bottom surface 12 . In other words, the edge face 13 is formed along the outer frame 111 of the upper face 11 and the outer frame of the lower face 12.

The electrode set 14 or a plurality of electrodes are disposed on the lower surface 12. Electrical energy (not shown) is applied to the LED semiconductor die 10 through the set of electrodes 14 to generate electro-luminescence and is emitted from the top surface 11 and the edge surface 13. No electrode is disposed on the top surface 11 in such a flip chip type semiconductor die 10 of the described embodiment.

The soft buffer layer 20 can be used to: 1) relieve internal stress caused by CTE mismatch among the components of the CSP LED device 1A; and 2) increase the bonding force between the LED semiconductor die 10 and the package structure 200 And 3) on the soft buffer layer 20 to facilitate the formation of the phosphorescent structure 30 to realize an approximate conformal coating. Specifically, the soft buffer layer 20 is a relatively soft material that is preferably made of a transparent polymer material such as silicon, epoxy, rubber, and the like. To illustrate, the soft buffer layer 20 includes an upper portion 21 and an end portion 22 (currently formed as a single process). An upper portion 21 is formed on the upper surface 11 of the LED semiconductor die 10 and an end portion 22 is formed to cover the edge surface 13 of the LED semiconductor die 10. The soft buffer layer 20 also substantially covers the top surface 11 and the edge surface 13 of the LED semiconductor die 10 but not the electrode set 14 of the LED semiconductor die 10.

As shown in Figure 1B (the cross section of the CSP LED device 1A that does not include the phosphorescent structure 30 and the encapsulation structure 40), the upper portion 21 has a convex surface 211 ). The highest point of the convex surface 211 is close to the center point of the upper surface 11 and is in alignment with the optical axis of the LED semiconductor die 10 and the lowest point of the convex surface 211 is close to the outer surface 111 of the upper surface 11 . Since the soft buffer layer is preferably made of a liquid polymer material through curing, a convex shape is formed due to the effect of the adhesion of the liquid polymer material. Thus, the upper portion 21 shows the convex surface 211. The distance from the highest point of the convex surface 211 to the top surface 11 (along the vertical direction shown in Fig. 1B) is less than about half the thickness of the LED semiconductor die 10 so that the convex surface 211 has a steep slope It is preferable to facilitate subsequent formation of a substantially continuous phosphor layer. The distance from the highest point of the convex surface 211 to the top surface 11 is about 45% or less of the thickness of the LED semiconductor die 10, about 40% or less, about 30% or less, about 20% % ≪ / RTI >

The end portion 22 includes an elongated surface 221 (upper surface of the end portion 22) connected to the convex surface 211. It will be appreciated that the extension surface 221 is continuously connected to the convex surface 211 such that both the extension surface 221 and the convex surface 211 have substantially the same curvature at the adjacent boundary. Continuously or gently connected extended surfaces 221 and convex surface 211 will aid in the subsequent formation of the phosphorescent structure 30 above the soft buffer layer 20.

The extended surface 221 and the convex surface 211 may be connected to each other and adjacent to each other near the outer frame 111 of the upper surface 11 of the LED semiconductor die 10 so that the outer frame 111 has the convex surface 211 Almost or close to the extended surface 221. In other words, the contiguous border between the outer frame 111 of the LED semiconductor die 10 and the extended surface 221 and the convex surface 211 is substantially parallel to the reduced shift or spacing, Such shift is as small as allowed and is specified by the manufacturing capabilities of the manufacturing process.

1B, the curvature of the extension surface 221 is opposite to the curvature of the convex surface 211. In other words, the curvature of the extension surface 221 is opposite to the curvature of the convex surface 211. In other words, Also, as the extension surface 221 is further away from the edge surface 13 of the LED semiconductor die 10, it becomes flatter and eventually the curvature becomes zero. An extended surface comprising such a target profile will facilitate the formation of the phosphorescent structure 30. [ According to other embodiments, the extension surface 221 may include a sloped surface (FIG. 1D) or a convex surface (FIG. 1E).

The soft buffer layer 20 is preferably formed by spraying a liquid polymeric material such as silicon onto the LED semiconductor die 10 and the polymeric material is in close contact with the upper surface 11 and the edge surface 13 of the LED semiconductor die 10 . The shape of the soft buffer layer 20 including the upper portion 21 and the end portion 22 is formed by the interaction of the surface tension and the adhesion force in the liquid polymer material itself and is formed after the hardening process.

The soft buffer layer 20 has a relatively low hardness to mitigate internal stress caused by CTE mismatch among the components of the CSP LED device 1A due to the greater deformation of the soft buffer layer 20 during the thermal cycling of the LED operation . The type of failure in which the package structure 200 is peeled off from the LED semiconductor die 10 due to internal stress is significantly suppressed. That is, the soft buffer layer 20 functions as a stress relaxation layer. If the hardness of the soft buffer layer 20 is too high, the capacity of the soft buffer layer 20 to support the larger strain is reduced. The ability to mitigate internal stress among the layers in the package structure 200 is also compromised. It is preferable that the hardness of the soft buffer layer 20 is not larger than A80 in Shore hardness standard such as A70, A60, A50 or A40 or less. The hardness of the soft buffer layer 20 is mainly determined by physical properties. Suitable manufacturing materials for the soft buffer layer 20 are selected by the required hardness. For example, the manufacturing material of the soft buffer layer 20 is a transparent polymeric material having a hardness substantially such as silicone rubber, epoxy, or the like.

The phosphorescent structure 30 is disposed on the soft buffer layer 20 to partially convert the wavelength emitted from the LED semiconductor die 10 through the soft buffer layer 20 to low-pass. Specifically, the phosphorescent structure 30 is conformally formed on the soft buffer layer 20 along the convex surface 211 and the extended surface 221 of the soft buffer layer 20.

1C is a cross-sectional view of the CSP LED device 1A without the encapsulation structure 40. Fig. The phosphorescent structure 30 includes an upper portion 310 and an end portion 32. An upper portion 31 of the phosphorescent structure 30 is formed on the upper portion 21 of the soft buffer layer 20 and an end portion 32 of the phosphorescent structure 30 is formed on the end portion 22 of the soft buffer layer 20. The upper portion 31 of the phosphorescent structure 30 is also gently and continuously connected to the end portion 32 of the phosphorescent structure 30 since the convex surface of the upper portion 21 is connected to the extending surface 2210 of the end portion 22 gently and continuously. .

The elongated surface 221 is a relatively gentle surface with a smaller slope that can smooth the steep "step" created by the edge surface 13 of the LED semiconductor die 10. [ In other words, the soft buffer layer 22 includes a gentle step profile and serves as a gentle layer to facilitate the subsequent formation of an approximate conformal coating of the phosphor powder. For example, the angle formed by the extension surface 2210 shown in FIG. 1C in the horizontal direction may be in the range of about 85 degrees or less, about 80 degrees or less, or about 90 degrees or less, such as about 75 degrees or less. When a coating process such as spraying is used to form the phosphorescent structure 30, precipitation of the phosphorescent material caused by gravity in the liquid polymeric resin material that covers the gentle step profile of the soft buffer layer 20 is significantly mitigated. Thus, a substantially continuous layer of phosphorescent material is formed to cover the convex surface 211 and the extended surface 221 of the soft buffer layer 20. Thus, an approximate conformal coating of the phosphorescent material for forming the phosphorescent structure 30 is realized. In other words, the phosphorescent structure 30 is substantially similar to the shape of the soft buffer layer 20 and may be a thin film structure substantially similar to the LED semiconductor die 10. Therefore, the blue light leakage problem in the CPS LED device is solved.

The phosphorescent structure 30 includes a resin material used for bonding the phosphorescent material and the phosphorescent material. For example, the binder material is selected from one of transparent polymeric resin materials such as silicone, epoxy and rubber. The binder material may be the same as or different from the material used to form the soft buffer layer 20. The method of forming the phosphor layer disclosed in U.S. Patent No. US2010 / 0119839 can be applied to form the phosphorescent structure 30 of the technical details totally integrated by various embodiments and references according to the present invention. A very thin and thin phosphor layer can be formed as the phosphorescent structure 30 by using the disclosed phosphor deposition method. One advantage is that the phosphor particles are deposited as a uniform, thin, and small conformal coating layer. Therefore, a substantially large "void" of the phosphorescent material will not be formed. As a result, the "blue light spot" phenomenon and the blue light leakage problem are solved and the risk of blue light harmful to the human eye is also reduced. Another advantage is that once the phosphorescent structure 30 with the high packing density is formed in the embodiment of the CSP LED device 1A according to the present invention, the phosphorescent structure 30 exhibits an improved conversion effect and thus the CSP LED device 1A can be used, Thereby improving the overall optical efficiency of the optical system. Various phosphorescent materials and polymeric resin materials having different refractive indexes can be deposited layer-by-layer according to the deposition sequence required to form the phosphorescent structure 30, so that the light extraction efficiency and the light conversion efficiency can be further improved.

The phosphorescent structure 30 of the disclosed embodiment includes a phosphorescent material and a polymeric material. For a relative CSP LED device, the phosphorescent structure is formed in direct contact with the LED semiconductor die. It will be appreciated that the phosphorescent structure generally comprises a powdery ceramic phosphor material distributed within the polymeric binder material. Ceramic materials, however, generally do not form a chemical bond with the LED semiconductor die during the CSP manufacturing process, thus reducing the adhesion to the LED semiconductor die. The adhesion between the phosphorescent structure and the LED semiconductor die is mainly improved from the polymeric binder material. When the phosphor powder is distributed within the polymeric binder material, the ratio of the interface between the polymeric material and the surface of the LED semiconductor die is reduced, thereby reducing the bonding force at the interface. In contrast to the CSP LED device 1A according to the present invention, the soft buffer layer 20 provides complete contact between the polymeric material and the LED semiconductor die 10, 30 have a greater bonding force to the soft buffer layer 20. [ Therefore, the bonding force between the phosphorescent structure 30 and the LED semiconductor die 10 can be significantly improved by introducing the soft buffer layer 20. Accordingly, the soft buffer layer 20 functions as an adhesion promoting layer.

An encapsulation structure 40 formed on the phosphorescent structure 30 as shown in FIG. 1A is disposed to protect the phosphorescent structure 30 as an environmental protection structure. The encapsulation structure 40 may not resemble the shape of the phosphorescent structure 30 and the soft buffer layer 20. Instead, the encapsulation structure 40 may be fabricated in a planar structure. The flat surface of the encapsulation structure 40 will facilitate pick-and-place processing with the robotic arm during a subsequent assembly process to bond the CSP LED device onto the substrate.

The hardness of the encapsulation structure 40 is equal to or greater than the hardness of the soft buffer layer 20. Preferably, the encapsulation structure 40 is harder than the soft buffer layer 20 to provide higher strength for better processing in future assembly processes. Specifically, it is preferable that the hardness of the sealing structure 40 is equal to or larger than D30 in the Shore hardness standard such as D35 or more, D45 or more, or D55 or more.

The manufacturing material determines the hardness of the encapsulation structure (40). Suitable manufacturing materials for the encapsulation structure 40 are selected by the required hardness. For example, the material of the encapsulation structure 40 is a substantially transparent polymeric material having the required hardness, such as silicone, rubber, epoxy, and the like.

According to the above detailed description, the CSP LED device 1A exhibits at least the following technical characteristics. For a relative CSP LED device, the phosphorescent structure 30 is in direct contact with the LED semiconductor die 10. The presence of the ceramic phosphor material reduces the contact area between the polymeric material and the LED semiconductor die 10, thereby reducing the bond strength between the two. Conversely, in the case of the CSP LED device 1A, the polymeric material of the soft buffer layer 20 is in full contact with the LED semiconductor die 10. Therefore, the bonding force between the phosphorescent structure 30 and the LED semiconductor die 10 is significantly increased by including the soft buffer layer 20. Furthermore, since the soft buffer layer 20 has a lower hardness, it can withstand a larger compression strain to mitigate the internal stress caused by the CTE mismatch among the components in the CSP LED diacer 1A. Since the soft buffer layer 20 increases the bonding force and alleviates the internal stress, the package structure 200 is easily peeled off from the LED semiconductor die 10 due to the internal stress generated by the thermal cycling during operation of the CSP LED device 1A It does not. In other words, the type of device failure due to peeling during operation of the CSP LED device 1A is significantly prevented or reliability is significantly improved.

Another feature of the CSP LED device 1A is that the extension surface 221 of the end portion 22 of the soft buffer layer 20 is a relatively gently sloped surface with a smaller slope of the gradient, Thereby making the more abrupt vertical step of the surface 13 gentle. Without a gentle, smaller gradient buffer layer 20, the phosphor powder tends to settle in the binder material due to the gravitational effect, so that the edge surface 13 of the LED semiconductor die 10 ), It may be difficult to secure the phosphor powder. On the other hand, the soft buffer layer 20 according to the CSP device 1A can greatly reduce the sedimentation effect of the phosphor powder generated by gravity, so that a substantially continuous phosphor powder distribution is formed along the end portion 22 of the soft buffer layer 20 . In other words, an approximate conformal coating with a phosphor powder inside the phosphorescent structure 30 is realized. Therefore, the blue light leakage problem of the CSP LED device is solved. Thus, the CSP LED device 1A according to the present invention exhibits better spatial color uniformity and CCT binning consistency is also improved.

As another technical feature of the CSP LED device 1A, a sequential deposition method of a phosphorescent material and a polymer material can be used to form the phosphorescent structure 30. [ A very small and thin phosphor layer like the phosphorescent structure 30 can be formed using the disclosed phosphor deposition method. One advantage is that the phosphor particles are deposited as a uniform, thin, and small conformal coating layer. So that a substantially "void" of phosphorescent material will not be formed. As a result, the "blue light spot" phenomenon and the blue light leakage problem are solved and the risk of blue light harmful to the human eye is also reduced. Another advantage is that once the phosphorescent structure 30 with the high packing density is formed in the embodiment of the CSP LED device 1A, the phosphorescent structure 30 exhibits a better conversion effect and thus the overall optical performance of the CSP LED device 1A The efficiency is improved. It will be appreciated that various photoluminescent materials and polymeric resin materials having different refractive indices can be deposited layer-by-layer according to the deposition sequence required to form the phosphorescent structure 30, thereby further improving light extraction efficiency and light conversion efficiency.

As another technical feature of the CSP LED device 1A, the refractive index of the encapsulation structure 40 can be selected to be smaller than the refractive index of the phosphorescent structure 30 and the refractive index of the phosphorescent structure 30 can be selected to be smaller than the refractive index of the soft buffer layer 20. [ Can be selected to be smaller. In other words, refractive index matching can be achieved in the package structure 200. That is, the refractive index of the package structure 200 is close to the refractive index of the surrounding environment (for example, air). Therefore, the total reflection (TIR) due to different refractive indexes along the optical path can be reduced, thereby improving the light extraction efficiency of the CSP LED device 1A.

As a further technical feature of the CSP LED device 1A, the slight deviation in the geometrical dimensions of the encapsulation structure 40 does not contain any phosphorescent material in the encapsulation structure 40 and therefore does not significantly affect the optical properties associated with wavelength conversion . That is, a manufacturing process such as dicing, molding, or the like that determines the outer lid dimension of the encapsulation structure 40 (i.e., the outer lid dimension of the CSP LED device 1A) will have more processing errors. However, the required optical properties, such as the spatial color uniformity of the CSP LED device 1A and the CCT binning consistency, are unaffected (and scarcely received) by the deviation of the outer cover dimensions due to processing errors.

As another technical feature of the CSP LED device 1A, the length and width of the outer lid dimensions of the package structure 200 are the same order of geometrical dimensions as the length and width of the LED semiconductor die 10. Compared to PLCC type LED package devices, the package dimensions are approximately three to twenty times greater than the package dimensions of the LED semiconductor die 10. The outer lid dimension of the package structure 200 according to the embodiment of the CSP LED device 1A is greater than or equal to 100% or less, or less than or equal to 50%, or less than or equal to 20% It should not be. In other words, the length and width of the package structure 200 should not be greater than or equal to 200% of the length and width of the corresponding LED semiconductor die 10, or greater than or equal to 150%, or greater than or equal to 120%. Because there is no additional submount (not shown) disposed below the LED semiconductor die 10, the CSP LED device 1A has a compact form factor. Further, a refractive structure can be selectively placed on the four peripheral edge surfaces (part or whole) of the package structure 200 to further define and limit the viewing angle of the CSP LED device 1A based on specifications in other applications .

As another technical feature of the CSP LED device 1A, the manufacturing material for forming the soft buffer layer 20 is a polymeric material that does not contain a substance (e.g., benzene) that chemically reacts with additives contained in the soldering flux It is preferable to select it. The reflow soldering process is usually used when a CSP LED device is bonded onto an application substrate such as a PCB. During the reflow soldering process, the soldering flux is typically used to improve the bond quality between the CSP LED device and the substrate. However, the additives contained within the soldering flux tend to react with the benzene found in the silicone binder material. This chemical reaction will form a harmful dark layer on the lower surface of the phosphorescent structure 30 when made of a polymeric material containing benzene. However, if the soft buffer layer 20 is composed of a polymeric material with no or substantially no benzene and is disposed according to the embodiment of FIG. IA, the photoluminescent structure 30 will block contact with the solder flux additive in a subsequent bonding process. Therefore, when the CSP LED device 1A is bonded onto the substrate through the reflow soldering process, the additive contained in the solder flux is confined substantially to the lower surface of the CSP LED device 1A by the soft buffer layer 20 and the phosphorescent structure 30 As shown in Fig. This harmful chemical reaction between the additive of the soldering flux and the benzene found in the (for example) silicon binder material used to make the phosphorescent structure 30 is thus prevented. Thus, the dark layer resulting from this chemical reaction is significantly reduced, and elements that degrade the optical efficiency and reliability of the CSP LED device 1A are also avoided. In other words, the soft buffer layer 20 also functions as an environmental barrier layer.

The above paragraphs are a detailed description of embodiments related to the CSP LED device 1A. A detailed description of another embodiment of the CSP LED device according to the present invention will be described as follows. Some detailed descriptions of the features and advantages found in the following embodiments of the light emitting device are similar to the features and advantages of the CSP LED device 1A and therefore are omitted for brevity purposes.

Figure 2 shows a schematic cross-sectional view of a second embodiment of a CSP LED device according to the present invention. The difference between the CSP LED device 1B and the CSP LED device 1A is that at least the encapsulation structure 40 further comprises a microstructured lens array layer 41. The microstructured lens array layer 41 and the encapsulation structure 40 can be fabricated together in one single process at the same time. The microstructured lens array layer 41 may comprise a plurality of microstructures 411 arranged in order or randomly on the surface of the encapsulation structure 40. Other forms of microstructure 411 may include hemispheres, pyramids, cones, pillars, etc., or may be rugged surfaces.

The microstructured lens array layer 41 may reduce the likelihood of light illuminated inside the CSP LED device 1B that is reflected back due to total reflection (TIR) at the interface of the encapsulation structure 40 with the surrounding environment. It is therefore easier for light to escape the encapsulation structure 40. Thus, the light extraction efficiency of the encapsulation structure 40 is improved and the optical efficiency of the CSP LED device 1B is also increased.

Figures 3A-3C show schematic cross-sectional views of a third embodiment of a CSP LED device according to the present invention. The difference between the CSP LED device 1C and the CSP LED device 1A as shown in Fig. 3A is that the soft buffer layer 20 of the CSP LED device 1C may further include light scattering particles 23. Fig. As shown in Figures 3B-3C, the encapsulation structure 40 may further include light scattering particles to form CSP LED devices 1C 'and 1C ". Both the soft buffer layer 20 and the encapsulation structure 40 are simultaneously light scattered Particles (not shown).

The light will be scattered by the scattering particles 23 and 42 of the devices 1C-1C ", so that optical performance such as spatial color uniformity of the CSP LED devices 1C-1C "can be further improved. The light scattering particles 23 and 42 may be selected from inorganic materials such as TiO ₂ , SiO ₂ , BN and Al ₂ O ₃ , other metals or non-metal oxides, and the like. The light scattering particles 23 can be uniformly distributed in the soft buffer layer 20 and the light scattering particles 42 can also be uniformly distributed in the encapsulation structure (as shown in FIG. 3A) (as shown in FIG. 3B) ). 3C, the light scattering particles 42 may be formed as a conformer layer such as to form a light scattering layer 43 over the phosphorescent structure 30 and in the phosphorescent structure 40. [

In the case of the above-described CSP LED devices 1A to 1C, each component such as the soft buffer layer 20, the phosphorescent structure 30, or the sealing structure 40 can be formed as a single layer structure or a multi-layer structure. When each component is a single layer structure, it is formed by solidifying the product material by a single curing process and is formed as a single curing process, respectively. When each component has a multi-layer structure, it is formed by solidifying the product material by a plurality of curing processes.

The following paragraphs describe a fabrication method for some embodiments of a CSP LED device in accordance with the present invention. The manufacturing method provides a method for manufacturing an LED device which is essentially the same as or similar to the CSP LED devices 1A to 1C as shown in Figs. It will therefore be appreciated that some of the details of the variations of the manufacturing method are omitted for the sake of brevity.

Figures 4A-4F illustrate a sequence of manufacturing steps for manufacturing a CSP LED device in accordance with some embodiments of the present invention. This manufacturing process includes at least three manufacturing steps: placing a plurality of LED semiconductor dies 10 on a release layer 300; Forming a plurality of package structures (200) on a plurality of LED semiconductor dies (10); And a plurality of package structures 200 are singulated. The detailed technical aspects of each manufacturing step are described as follows.

A release layer 300, such as a release film, as shown in FIG. 4A, may be first prepared and the release layer 300 disposed on a substrate (e.g., a silicon substrate or a glass substrate, not shown). A plurality of LED semiconductor dies 10 (two LED semiconductor dies 10 in the illustrated example are shown) are then placed over the release layer 300 to form the array 100 of LED semiconductor dies 10 . The electrode set 14 of each LED semiconductor die 10 is embedded in a release layer 300 such that the bottom surface 12 of the LED semiconductor die 10 is bonded to the release layer 300 and is separated by the release layer 300 It is preferable to cover it.

A number of package structures 200 after the arrangement for forming the array 100 of LED semiconductor dies 10 disposed on the release layer 300 as shown in Figures 4B through 4D are applied to the array of LED semiconductor dies 10. [ (100). In this manufacturing step, a plurality of package structures 200 are interconnected. Specifically, the procedure for forming the package structure 200 on the LED semiconductor die 10 is embodied in the following three steps.

An array of soft buffer layers 20 is formed on the array 100 of LED semiconductor dies 10 as shown in Figure 4B in a first step to form the package structure 200 on the LED semiconductor die 10. Specifically, the liquid polymeric material used to fabricate the soft buffer layer 20 is sprayed onto the array of LED semiconductor dies 10 and then the liquid polymeric material spreads over the top surface 11 of each LED semiconductor die 10 (The liquid polymeric material also spreads over the release layer 300). The soft buffer layer 20 (e.g., such as the convex upper portion 21 and the concave end portion 222 as described in the first embodiment of FIG. IA) is formed through the interaction and balance of the surface tension and the adhesive force of the liquid polymeric material itself. . The liquid polymer material is then cured and solidified. The highest point of the soft buffer layer 20 is formed near the center point of the top surface 11 and is in line with the optical axis of the LED semiconductor die 10. [

In addition to the spray process, the liquid polymeric material used to fabricate the soft buffer layer 20 may be coated on the array 100 of LED semiconductor dies 10 by spin coating or the like. It will be appreciated that the light scattering particles 23 may be premixed in a liquid polymeric material. Accordingly, a soft buffer layer 20 comprising light scattering particles 23 is formed according to the embodiment of the CSP LED device 1C shown in Fig. 3A.

In a second step of forming the package structure 200 on the LED semiconductor die 10, an array of phosphorescent structures 40 is formed on the soft buffer layer < RTI ID = 0.0 >Lt; RTI ID = 0.0 > 20 < / RTI > The conformal phosphorescent structure 30 is preferably formed using the method disclosed in U. S. Patent No. US2010 / 0119839. Specifically, a carrier substrate for moving the array of LED semiconductor dies 10 and the array of soft buffer layers 20 provided by the manufacturing step is disposed in a process chamber (not shown), so that the phosphorescent material and the polymer material As shown in Fig. In order to manufacture the phosphorescent structure 30, densely packed phosphorescent particles are dispersed in the process chamber, uniformly disposed on the carrier substrate, and then the carrier substrate is disposed in another process chamber so that the polymer material is combined with the phosphorescent particles as a complex phosphorescent layer Lt; RTI ID = 0.0 > carrier substrate. ≪ / RTI > Such a manufacturing process for preparing a layer of phosphorescent particles and preparing a polymeric binder layer may be carried out in reverse order.

Although the arrangement for forming the array of LED semiconductor dies 10 on the release layer 300 may be difficult when the phosphorescent structures 30 are formed through the conformal coating process, Can be formed uniformly and symmetrically on the array of LED semiconductor dies 10 because of the nature of the process, making them suitable for mass production. Conversely, when the phosphorescent structure is formed by molding or screen printing, an incorrect array of LED semiconductor die arrays will affect the uniformity and symmetry of the phosphorescent structure.

In a third step of forming the package structure 200 on the LED semiconductor die 10, an array of encapsulation structures 40 is formed on the array of phosphorescent structures 30 as shown in Fig. 4D. The liquid polymeric material used to make the encapsulation structure 40 in the process of forming the encapsulation structure 40 is placed in the phosphorescent structure 30 by, for example, dosing, injection, molding, spin coating, . The light scattering particles 42 may also be premixed in a liquid polymeric material. Thus, the encapsulation structure 40 comprising the light scattering particles 42 is formed according to the embodiment shown in FIG. 3B.

When the encapsulation structure 40 further comprises a microstructure lens array layer 41, the microstructured lens array layer 41 may be formed at the same time as or after the encapsulation structure 40 is formed, 40). When using a molding process, the encapsulation structure 40 and the microstructured lens array layer 410 can be formed simultaneously in one single process.

A number of connected package structures 200 are formed using a fabrication process to form the package structure 200 on the LED semiconductor die 10 to cover the plurality of LED semiconductor die 10. Then, the release layer 300 is removed as shown in FIG. 4E. A number of connected package structures 200 are then singulated by dicing to secure a plurality of discrete CSP LED devices 1, as shown in FIG. 4F. Alternatively, release layer 300 may be removed after multiple package structures 200 are singulated.

(E. G., ≪ RTI ID = 0.0 > example) < / RTI > to isolate the package structure 200 equally at locations where the extension surface 221 of the soft buffer layer 20 has a minimum curvature or slope during a manufacturing process to singulate multiple connected package structures 200 For example, a top) is preferably used. In other words, the cutting position tends to be further away from the edge surface 13 of the LED semiconductor die 10. The package structure 200 is therefore diced in a relatively flat or flat section 321 of the end 32 of the phosphorescent structure 30. [ In this way, the spatial color uniformity of the CSP LED device 1 will not be significantly affected by the variation in the dicing position tolerance. Specifically, the positional tolerance for the dicing process can cause irregular dimensions of the flat section 321 of the phosphorescent structure 30 relative to the CSP LED device 10. However, since the light emitted from the LED semiconductor die 10 includes the viewing angle range and does not pass through the flat section 321, the change in size within the flat section 3211 hardly affects the spatial color uniformity.

In a summary of some embodiments, a method of manufacturing a CSP LED device according to the present invention provides a method for manufacturing an LED device 1 in a batch process suitable for mass production. According to this embodiment, the CSP LED device 1 exhibits improved reliability, improved spatial color uniformity, more consistent CCT binning, and higher optical efficiency and is realized in a much smaller form factor.

In addition, the mold for manufacturing the CSP LED device 1 according to the manufacturing method described in this description can be omitted. In other words, the size of the CSLP LED device 1 is not specified by the size of the mold and is instead determined by the arranged pitch of the array of LED semiconductor dies 10. [ Therefore, the disclosed manufacturing method is considerably scalable and applicable for manufacturing CSP LED devices of a wide range of dimensions.

Although the description of the present invention has been described with reference to specific embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the true spirit and scope of the invention as defined by the appended claims. Can be replaced in a corresponding manner. It is also to be understood that the purpose, scope, and range of the present invention may be modified in various ways to suit particular situations, compositions of materials, methods, or processes. All such modifications should be made within the scope of the appended claims. In particular, although the methods disclosed herein are described with reference to particular acts performed by a particular order, such acts may be combined, subdivided, or rearranged to form corresponding methods that do not depart from the teachings of the invention have. Accordingly, the order and classification of operations are not limited to the disclosure of the present invention unless specifically described.

Claims (15)

As a light emitting device,
Wherein the edge surface extends between an upper surface of the LED semiconductor die and a lower surface of the LED semiconductor die, the set of electrodes including an upper surface, a lower surface opposite the upper surface, an edge surface and an electrode set, A flip chip light emitting diode (LED) semiconductor die disposed on the underside; And
Wherein the upper portion is disposed on the upper surface of the LED semiconductor die and includes a convex surface and the end portion is disposed so that the LED The soft buffer layer covering an edge surface of the semiconductor die and including an extending surface, the convex surface of the upper portion of the soft buffer layer being adjacent to the extending surface of the end portion of the soft buffer layer;
A phosphorescent structure disposed on the soft buffer layer over the convex surface and the extended surface; And
And a package structure disposed on the phosphorescent structure and including an encapsulation structure having a hardness greater than a hardness of the soft buffer layer,
Wherein the upper surface of the LED semiconductor die comprises a rim and a boundary between the convex surface and the extended surface of the soft buffer layer is in contact with or adjacent to the rim on the upper surface of the LED semiconductor die, Wherein the extended surface has the same curvature at the boundary.
The method according to claim 1,
Wherein the width and length of the package structure do not exceed 200% of the width and length of the LED semiconductor die.
The method according to claim 1,
Wherein the shape of the extended surface of the soft buffer layer is concave.
The method according to claim 1,
Wherein said hardness of said soft buffer layer does not exceed A80 in Shore hardness standard and said hardness of said encapsulation structure is not less than D30 in Shore hardness standard.
The method according to claim 1,
Wherein the material of the soft buffer layer comprises at least one of silicon, epoxy or rubber, and the material of the sealing structure comprises at least one of silicon, epoxy or rubber.
6. The method according to any one of claims 1 to 5,
Wherein the encapsulation structure further comprises a microstructured lens array layer.
6. The method according to any one of claims 1 to 5,
Wherein at least one of said soft buffer layer or said encapsulation structure comprises light scattering particles.
6. The method according to any one of claims 1 to 5,
Wherein the encapsulation structure further comprises a light-scattering layer including light-scattering particles and covering the phosphorescent structure.
5. The method according to any one of claims 1 to 4,
Wherein the soft buffer layer, the phosphorescent structure and the encapsulation structure of the package structure each include at least one layer of a polymeric resin material.
A method of manufacturing a light emitting device,
Arranging a plurality of flip chip LED semiconductor die on a release layer to form an array of flip chip LED semiconductor die;
Forming an array of package structures coupled over the array of flip chip LED semiconductor dies,
Spraying or spin coating a liquid polymeric material onto the array of flip chip LED semiconductor die to form an array of soft buffer layers on top of the array of flip chip LED semiconductor dice, each soft buffer layer comprising an upper portion and an end portion, A plurality of LED semiconductor die encapsulant layers disposed on an upper surface of each LED semiconductor die and disposed at the ends to cover an edge surface of each LED semiconductor die and the upper convex surface of the soft buffer layer is adjacent to an extension surface of the end portion of the soft buffer layer And,
Forming an array of phosphorescent structures on the array of soft buffer layers along the convex surface and the extended surface,
Forming an array of encapsulation structures over the array of phosphorescent structures, wherein the encapsulation structure has a hardness that is greater than a hardness of the soft buffer layer; And
Lt; RTI ID = 0.0 > 1, < / RTI > and singulating the array of package structures.
11. The method of claim 10,
Forming the array of phosphorescent structures over the array of soft buffer layers comprises moving an array of flip chip LED semiconductor die covered by the array of soft buffer layers to a process chamber using a carrier substrate;
Disposing a layer of phosphorescent material on the surface of the carrier substrate; And
And forming a polymeric binder layer on the layer of the phosphorescent material.
11. The method of claim 10,
Wherein forming the array of encapsulation structures over the array of phosphorescent structures comprises a spray process, a spin coating process, a molding process, or a dosing process.
11. The method of claim 10,
Further comprising the step of removing said release layer before or after singulation of said array of package structures.
11. The method of claim 10,
Wherein forming the array of encapsulation structures over the array of phosphorescent structures comprises forming a microstructured lens array layer over the array of encapsulation structures.
15. The method of claim 14,
Wherein forming the array of microstructured lens array layers and the encapsulation structure comprises a single molding process.

Images