TWI473222B - Chip structure having imitation gold bumps - Google Patents

Description

Wafer structure with imitation gold bumps

The present invention relates to a semiconductor device, and more particularly to a wafer structure having a gold-like bump

Flip-chip bonding technology and Inner Lead Bonding (ILB) are used to place a plurality of conductive bumps (or protruding electrodes) on the pads of the active surface of the wafer. The wafer flips or presses the inner leads to allow the bumps to engage a substrate to complete the electrical connection. Compared with the electrical connection method using wire bond, it provides a short electrical connection path from the wafer to the substrate and a product suitable for high-density output/input point, with good high-frequency signal. Transmission quality.

At present, the more common flip chip bonding or internal pin bonding technology is the bonding technique using Au bump, which is electrically connected to the substrate by thermocompression or anisotropic conductive paste. Although its reliability is better and there is no bridging short circuit problem of reflowing into a spherical shape, due to the high material cost, it is still necessary to develop a replacement bump of the same quality.

Recently, a low-cost copper bump has been proposed to replace the gold bump. However, the copper bump has poor ductility due to its relatively hard texture, so the stress applied to the copper bump is directly transmitted to the copper bump and the wafer metal pad. Bonding the interface causes the bottom of the copper bump to break or damage the wafer. Especially when a plurality of bumps cannot control a fairly accurate contour or a situation in which the flip-chip gap between the substrate and the wafer is non-uniform (for example, when the substrate is warped), the problem of bottom cracking of the copper bump becomes more complicated. serious. In addition, the copper bumps are prone to oxidation problems, must be maintained in a reducing atmosphere during the process, and must be additionally protected against oxidation after the bumps are formed. There are many process limitations that cannot effectively reduce the manufacturing cost of the bumps.

In order to solve the above problems, the main object of the present invention is to provide a wafer structure having a gold-like bump, which can avoid the oxidation problem caused by the exposure of the bump due to the piercing of the anti-submersible layer during detection, and can also avoid The bump is directly pressed when the inner pin is pressed and the bump is damaged.

A second object of the present invention is to provide a wafer structure having imitation gold bumps, forming a gold bump which can replace the gold bumps, which is superior to the conventional copper bumps, and has no bottom fracture problem of the copper bumps. It can meet the requirements of lead-free, high reliability and low cost bumps.

The object of the present invention and solving the technical problems thereof are achieved by the following technical solutions. The invention discloses a wafer structure with imitation gold bumps, which mainly comprises a wafer, a under bump metal layer, a plurality of composite metal bumps and an anti-dense layer. The wafer has a plurality of pads and a protective layer covering a surface of the wafer and forming a plurality of openings to expose the pads. The under bump metal layer is disposed on the pads and covers the periphery of the openings of the protective layer. Each of the composite metal bumps is formed by a stack of a body and a joint portion, and the system is aligned with the pads and disposed on the underlying metal layer of the bumps. The joint is disposed on the body, wherein the system comprises a silver (Ag) content of not less than 99% by weight, the material of the joint is selected from gold (Au), and the thickness of the joint is less than the The thickness of the body. The anti-situ layer is formed on an upper surface of the joint and a first outer side and a second outer side of the body to completely cover the composite metal bumps.

The object of the present invention and solving the technical problems thereof can be further achieved by the following technical measures.

In the foregoing wafer structure having a gold-like bump, the first outer side of the joint and the second outer side of the body may be mutually aligned to form a pillar sidewall.

In the foregoing wafer structure having gold-like bumps, the under bump metal layer may have side edges not covered by the body, and the side edges are relatively recessed to the second outer side.

In the foregoing wafer structure having a gold-like bump, a joint surface may be formed between the body and the joint portion, and the joint surface is non-flat.

In the above wafer structure having a gold-like bump, the under-metal layer of the bump may have an adhesive layer and a conductive layer attached to the pad, and the conductive layer is attached to the adhesive layer. On the floor.

In the foregoing wafer structure having gold-like bumps, the anti-potential layer may cover the side edges of the conductive layer to expose the side edges of the adhesive layer.

In the foregoing wafer structure having a gold-like bump, the material of the anti-dip layer may be selected from one of gold (Au), palladium (Pd), copper (Cu) and nickel (Ni).

In the foregoing wafer structure having imitation gold bumps, the anti-potential layer may be selected from one of replacement gold and reduced gold to have oxidation resistance and high conductivity.

In the foregoing wafer structure having a gold-like bump, the upper surface of the joint portion and the first outer side edge may be angularly curved.

In the foregoing wafer structure having gold-like bumps, the thickness of the body may be between 6 μm and 20 μm, the thickness of the joint portion is between 2 μm and 6 μm, and the thickness of the anti-steep layer is not more than 1 μm.

In the foregoing wafer structure having a gold-like bump, the thickness of the joint portion may be greater than the thickness of the anti-stiction layer.

In the foregoing wafer structure having imitation gold bumps, the composite metal bump outer shape may be selected from one of a cylinder, a cube, and a rectangular parallelepiped.

It can be seen from the above technical solutions that the wafer structure with the imitation gold bump of the present invention has the following advantages and effects:

1. A specific combination of the body, the joint and the anti-situ layer can be used as one of the technical means. Since each composite metal bump is formed by stacking the body and the joint, the joint is disposed on the body. Moreover, the thickness of the joint portion is much larger than the thickness of the anti-potential layer, so that the probe can be prevented from being pierced by the probe because the anti-potential layer is too thin during the detection, and the oxidation problem caused by the exposure of the composite metal bump can also be avoided. When the pin is pressed, it directly touches the body and causes the composite metal bump to be damaged.

Second, the specific combination relationship between the composite metal bump and the anti-dense layer can be used as one of the technical means. Since the body of the composite metal bump contains a silver content of not less than 99% by weight, the joint portion of the composite metal bump The material is selected from gold, forming a gold-like bump that can replace gold bumps. It is better than the conventional copper bumps. It does not have the problem of bottom cracking of copper bumps, and can meet lead-free, high reliability and low. The bump requirement for cost. In addition, the use of the anti-situ layer coated on the surface of the composite metal bump can also avoid the slow deformation phenomenon of the composite metal bump under the action of stress.

Third, the specific combination relationship between the composite metal bump and the anti-situ layer can be used as one of the technical means. Since the anti-situ layer is a replacement gold (or reduced gold) and completely covers the composite metal bump, it is resistant. The processing time of the latent change is short, and the thickness can be controlled within 1 μm, which can avoid the occurrence of the latent change of the composite metal bump, and will not make the size of the composite metal bump laterally larger, so that no crystal chip will be generated at high temperature. The gap changes, with lower cost and thinner thickness.

Fourth, the non-flat joint surface between the inner metal body of the composite metal bump and the joint portion and the complete anti-latency layer can be completely covered to avoid separation or deformation of the joint portion in the composite metal bump.

The embodiments of the present invention will be described in detail below with reference to the accompanying drawings in which FIG. The components and combinations related to this case, the components shown in the figure are not drawn in proportion to the actual number, shape and size of the actual implementation. Some size ratios are proportional to other related sizes or have been exaggerated or simplified to provide clearer description of. The actual number, shape and size ratio of the implementation is an optional design, and the detailed component layout may be more complicated.

According to a first embodiment of the present invention, a wafer structure 100 having a gold-like bump is exemplified in a partial cross-sectional view of FIG. 1 and a cross-sectional view of an element in a process of FIGS. 2A to 2G. The wafer structure 100 with gold-like bumps of the present invention mainly comprises a wafer 110, an under bump metal layer 120, a plurality of composite metal bumps 130, and an anti-dense layer 140. The wafer 110 has a plurality of pads 111 and a protective layer 112. The protective layer 112 covers a surface 113 of the wafer 110 and is formed with a plurality of openings 114 to expose the pads 111. The wafer 110 is made of a semiconductor material, such as a germanium or a III-V semiconductor, and the surface 113 may be an active surface of the wafer 110. The integrated circuit component may be formed, for example, selected from a microcontroller. A microprocessor, a memory, a logic circuit, a special application integrated circuit (for example, a display driving circuit), or the like, or any combination thereof. The pads 111 are made of metal, such as aluminum, copper, and alloys thereof, and can be used as terminals for the signal input and output of the wafer 110. The protective layer 112 is an electrically insulating surface layer, or a passivation layer, and the material may be polyamidoamine, benzocyclobutene (BCB), phosphosilicate glass, or cerium oxide. Silicon oxide, silicon nitride or nitride, formed by chemical vapor deposition (CVD) techniques, can provide protection of the integrated circuit components on the surface 113 and cause the surface 113 More flat. In the present embodiment, the openings 114 of the protective layer 112 partially cover the periphery of the pads 111, that is, the openings 114 are slightly smaller in size than the pads 111.

Referring to FIG. 1 , the under bump metal layer 120 is disposed on the pads 111 and covers the periphery of the openings 114 of the protective layer 112 . The under bump metal layer 120 is in the form of a spacer for providing the composite metal bumps 130, and the solder pads 111 are electrically connected to the under bump metal layer 120 corresponding to the position. In particular, the under bump metal layer 120 can have an adhesive layer 121 and a conductive layer 122 for enhancing the connection between the composite metal bumps 130 and the pads 111. Further, the adhesive layer 121 is attached to the solder pad 111, and the solder pads 111 can be provided with good adhesion to the protective layer 112 and have a barrier function to prevent metal diffusion. The material of the adhesive layer 121 may be titanium (Ti) or titanium tungsten (TiW). The conductive layer 122 is attached to the adhesive layer 121. The conductive layer 122 has a higher conductivity than the adhesive layer 121 and can be thinner, and can be used as a plating seed layer for forming the composite metal bumps 130 ( The conductive layer 122 can provide good adhesion to the composite metal bumps 130. The conductive layer 122 can be made of gold (Au). In this embodiment, the adhesive layer 121 and the conductive layer 122 can be formed by electroplating, sputtering or chemical vapor deposition. Generally, the under bump metal layer 120 may be slightly larger than the openings 114 of the protective layer 112 to extend to the periphery of the corresponding opening 114 of the protective layer 112.

Referring to FIG. 1 again, each of the composite metal bumps 130 is formed by a stack of a body 131 and a joint portion 132. The body 131 is aligned with the pads 111 and disposed on the pillars 111. The joint portion 132 is disposed on the body 131, wherein the body 131 includes a silver (Ag) content of not less than 99% by weight, and the material of the joint portion 132 is selected from gold ( Au), and the thickness of the joint portion 132 is smaller than the thickness of the body 131. In this embodiment, one of the first outer side 134 of the joint portion 132 and the second outer side 135 of the body 131 are mutually aligned to form a cylindrical outer side surface, and the joint portion 132 An upper surface 133 and the first outer side 134 may be angled, for example, about 90 degrees, to define the area of the upper surface 133 to effectively control the bump joint area, which is beneficial for non-reflow conductive Engage. Regarding the columnar patterns of the composite metal bumps 130, the height of the composite metal bumps 130 may be greater than the diameter or a width of one of the bottom areas of the composite metal bumps 130. The thickness of the body 131 of each of the composite metal bumps 130 may be between 6 μm and 20 μm, and the thickness of the joint portion 132 is between 2 μm and 6 μm. In addition, since the body 131 of the composite metal bumps 130 contains a silver content of not less than 99% by weight, it has extremely high purity, is suitable for being formed in a large amount by electroplating, and has the effect of achieving homogenization in the electroplating process. There is no difference in the hardness of the bump due to the defect of uneven dispersion of the components, and the joint portion 132 has the characteristics of gold (Au) and the bonding effect. Therefore, the composite metal bumps 130 can be the same as the conventional gold bumps, have the same hardness as the conventional gold bumps but lower than the copper bumps, and have good electrical conductivity and metal elongation. Moreover, the cost of the composite metal bumps 130 is lower than the cost of the conventional gold bumps, and meets the requirements of lead-free, and can form imitation gold bumps without affecting the performance and quality of the bumps. In order to replace the conventional gold bumps, it is better than the conventional copper bumps, and there is no problem of the bottom crack of the conventional copper bumps.

Referring to FIG. 1 , the anti-situ layer 140 is formed on the upper surface 133 of the joint portion 132 and the first outer side 134 and the second outer side 135 of the body 131 to completely cover The composite metal bumps 130. The main function of the anti-situ layer 140 is to prevent the body 131 of the composite metal bumps 130 from generating a latent phenomenon of silver from the second outer side 135. The anti-steep layer 140 has a thickness of no more than 1 μm and may be about 0.03 to 0.3 μm. As shown in FIG. 4, since the thickness of the joint portion 132 can be much larger than the thickness of the anti-dive layer 140, it can be avoided that the probe 30 is too thin during probing because the anti-dive layer 140 is too thin. The piercing causes oxidation problems caused by the exposure of the silver component of the composite metal bumps 130. In this embodiment, the material of the anti-situ layer 140 may be selected from one of gold (Au), palladium (Pd), copper (Cu) and nickel (Ni), and may be a pure metal or an alloy. Preferably, the anti-situ layer 140 is selected from one of displacement Au and reduced Au, so that it has anti-oxidation and high-conductivity characteristics, so the anti-potential treatment The short time and the formation thickness can be controlled within 1 μm (micrometers) (about tens to hundreds of angstroms), the occurrence of the latent deformation of the composite metal bumps 130 can be avoided, and the composite metal bumps are not caused. The size of the 130 is increased laterally, so that no change in the flip-chip gap occurs at high temperatures, and the effect is lower and the thickness is thinner. In particular, the hardness of the anti-situ layer 140 may not be higher than or close to the hardness of the composite metal bumps 130, and does not require the reinforcement of the bump structure, so the thickness of the anti-dive layer 140 is increased. The reduction does not affect and change the structural strength of the overall bump. Therefore, as shown in FIG. 5, when the inner lead 40 is pressed onto the composite metal bumps 130 in the inner lead bonding process, since the joint portion 132 has a certain thickness, it is received therein. After the pin 40 is pressed, the joint portion 132 is slightly expanded to the left and right sides, but the inner lead 40 is not directly touched to the body 131, except that the composite metal bump 130 is exposed. Oxidation problem, even when the inner lead 40 is over-extruded to cause damage to the anti-situ layer 140, since the material of the joint portion 132 can be selected from gold, it is similar to the anti-dip layer 140. The material can also actively compensate for the damage of the anti-situ layer 140 without affecting the overall electrical connection quality.

In general, a metal material does not easily change when it is subjected to a stress below the elastic limit at a normal temperature for a long period of time. However, in a high temperature environment, when subjected to stress lower than the elastic limit, the metal material gradually deforms with time, and this phenomenon is called creep. Since the latent phenomenon of the composite metal bump 130 is higher than that of the gold bump and the copper bump, the present invention must utilize the film coating effect of the anti-situ layer 140 on the surface of the composite metal bump 130. In particular, the body 131 of the composite metal bumps 130 is covered to avoid the phenomenon that the composite metal bumps 130 undergo a latent deformation under long-term stress to cause slow deformation, and the composite metal bumps 130 are prevented from being deformed. The laterally fattening deformation maintains the flip-chip gap and achieves effective engagement.

Referring to Figures 2A through 2G, the present invention further illustrates the method of fabricating the wafer structure 100 having gold-like bumps to demonstrate the efficacy of the present invention.

First, as shown in FIG. 2A, a wafer 110 is provided. The plurality of wafers 110 can be formed in a wafer. The wafer 110 has a plurality of pads 111 and a protective layer 112. The protective layer 112 is provided. Covering one surface 113 of the wafer 110 and having a plurality of openings 114 to expose the pads 111.

Next, as shown in FIG. 2B, the metal layer including the under bump metal layer 120 covers the protective layer 112 of the wafer 110 and the pads 111. The under bump metal layer 120 may include the adhesion layer 121 and the conductive layer 122 described above, and may be formed by a deposition technique known in the semiconductor process, such as sputtering. In this step, the under bump metal layer 120, which has not yet defined the area size, covers the entire protective layer 112 and the exposed pads 111.

Thereafter, as shown in FIG. 2C, a patterned mask is formed, for example, a photoresist layer 10 is formed on the outer surface of the metal layer. In general, the photoresist layer 10 can be selected from a liquid photoresist or a dry film photoresist, and then an exposure and development process is performed to form a plurality of openings 11 to correspondingly expose the pads 111 to form the protrusions. The position of the underlying metal layer 120. The openings 11 are provided as regions for forming the composite metal bumps 130 and the under bump metal layers 120. In the embodiment, the openings 11 are larger than the pads 111 of the corresponding positions. Alternatively, without limitation, the openings 11 may be formed outside the pads 111, and the position of the contacts needs to be changed in accordance with the design of the contact arrangement in the RDL (reconfiguration line layer) process. .

Next, as shown in FIG. 2D, the plurality of bodies 131 are formed by electroplating in the openings 114, and the bodies 131 are bonded to the under bump metal layer 120. Then, as shown in FIG. 2E, a plurality of bonding portions 132 may be formed on the body 131 along the same photoresist layer 10 to form a plurality of composite metal bumps 130 without additionally adding a patterned mask. Set the cost.

Next, as shown in FIG. 2F, the photoresist layer 10 is removed such that the portion of the metal layer that does not include the under bump metal layer 120 is exposed. Then, as shown in FIG. 2G, a portion of the adhesive layer 121 and the conductive layer 122 may be removed by etching to form the under bump metal layer 120, which may be sized by the bottom of the composite metal bumps 130. Coverage area is defined. Each of the composite metal bumps 130 forms a first outer side 134 of the joint portion 132 and a second outer side 135 of the body 131, and the first outer side 134 and the second outer side The side edges 135 are aligned with each other.

Finally, as shown in FIG. 1 , an anti-substance layer 140 is formed on one of the upper surface 133 of the joint portion 132 and the first outer side 134 and the second outer side 135 of the body 131 . The anti-situ layer 140 can be formed by replacement gold, electroplating or electroless plating. By coating the composite metal bumps 130 with the anti-situ layer 140, the body 131 of the composite metal bumps 130 can be prevented from generating a creep phenomenon.

Specifically, the composite metal bump outer shape may be selected from one of a cylinder, a cube, and a rectangular parallelepiped, but is not limited thereto, and may be a polygonal cylinder of various shapes. In this embodiment, as shown in FIG. 3A, the composite metal bumps 130 are formed in a cubic shape so that the upper surface 133 is square, and each composite metal bump 130 has four columns outside the body. The side surface of each column includes a first outer side 134 of the joint portion 132 and a second outer side 135 of the body 131 correspondingly aligned, and is also square, and can be applied to a matrix arrangement or a fine pitch arrangement. Flip chip bonding. In another shape variation, as shown in FIG. 3B, the composite metal bump 130' is shaped like a cylinder so that the upper surface 133' is circular, and each composite metal bump 130' The outer surface of the outer surface of the arc-shaped column includes the outer side of the joint portion 132' and the outer side of the body 131' which is correspondingly aligned, and can be applied to the flip chip bonding of the matrix arrangement or the fine pitch arrangement, and It helps to fill the underfill to prevent the formation of voids. In another shape change example, as shown in FIG. 3C, the composite metal bumps 130" are formed in a rectangular parallelepiped shape such that the upper surface 133" is rectangular, and each composite metal bump 130" There are four outer side faces of the column, and the outer side of each column includes the outer side of the engaging portion 132" and the side of the body 131" which is correspondingly aligned, and is a rectangular or square corresponding to each other, and can be applied inside. Pin bonding.

In accordance with a second embodiment of the present invention, another wafer structure 200 of gold-like bumps is illustrated in cross-section in FIG. The imitation gold bump wafer structure 200 mainly includes a wafer 110, a bump under metal layer 120, a plurality of composite metal bumps 130, and an anti-dense layer 140. The same elements as those in the first embodiment will be designated by the same reference numerals and will not be described in detail.

In this embodiment, the under bump metal layer 120 may have a side edge 123 not covered by the body 131, and the side edge 123 is relatively recessed to the second outer side 135, and the anti-potential Layer 140 is partially covered to the under bump metal layer 120. In detail, the anti-situ layer 140 may cover the side edges of the conductive layer 122 but expose the side edges of the adhesive layer 121. Therefore, the anti-dip layer 140 is not brought into contact with the protective layer 112 of the wafer 110 to achieve high-density arrangement of the bumps, and the bonding force between the wafer and the substrate can be increased, thereby improving the transmission quality of the high-frequency signal. Further, since the anti-dive layer 140 does not contact the protective layer 112 of the wafer 110, a buffer space can be generated to control the anti-dive layer 140 to completely cover the surface of the composite metal bump 130. The protective layer 112 is not extended to reduce the problem of short circuit between the bumps, and the composite metal bump 130 can be prevented from being broken from the bottom of the composite metal bump 130 by deformation to the wafer 110, affecting The overall electrical connection effect. In addition, as shown in FIG. 6 , since each composite metal bump 130 is formed by electroplating, a joint surface 250 is formed between the body 131 and the joint portion 132 , and the joint surface 250 is formed. It is not flat. Therefore, the separation or deformation of the joint portion 132 in the composite metal bumps 130 can be avoided by the non-flat joint surface 251 and the complete coverage of the anti-dive layer 140. In detail, the body 131 forms a non-flat interface surface 250 along with the recess of the under bump metal layer 120, and the recess depth of the joint surface 250 is slightly the recess depth of the under bump metal layer 120. Half.

In summary, the wafer structure with the imitation gold bump of the present invention utilizes the anti-dip layer to coat the composite metal bump, which can avoid the occurrence of the latent change of the composite metal bump, so that no change in the flip-chip gap occurs at high temperature. The problem can meet the requirements of lead-free, high reliability and low cost bumps. Therefore, the composite metal bumps can be specifically applied to the columnar bumps on the semiconductor wafer. Moreover, since the anti-dense layer does not contact the protective layer, a high-density arrangement of the bumps can be achieved to increase the bonding force between the wafer and the substrate, thereby improving the transmission quality of the high-frequency signal.

The above is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Although the present invention has been disclosed in the above preferred embodiments, it is not intended to limit the present invention. Any simple modifications, equivalent changes and modifications made without departing from the technical scope of the present invention are still within the technical scope of the present invention.

10. . . Photoresist layer

11. . . Opening

20. . . Substrate

twenty one. . . surface

twenty two. . . Connection pad

30. . . Probe

40. . . Inner pin

100. . . Wafer structure with imitation gold bumps

110. . . Wafer

111. . . Solder pad

112. . . The protective layer

113. . . surface

114. . . Opening

120. . . Under bump metal layer

121. . . Adhesive layer

122. . . Conductive layer

123. . . Side edge

130. . . Composite metal bump

131. . . Ontology

132. . . Joint

133. . . Upper surface

134. . . First outer side

135. . . Second outer side

130’. . . Composite metal bump

131’. . . Ontology

132’. . . Joint

133’. . . Upper surface

130"...composite metal bumps

131"... body

132"...joining

133"... upper surface

140. . . Anti-substitute layer

200. . . Wafer structure with imitation gold bumps

250. . . Joint surface

Figure 1 is a partial cross-sectional view showing a wafer structure having gold-like bumps in accordance with a first embodiment of the present invention.

2A to 2G are views showing a cross-sectional view of an element in a process of a wafer structure having a gold-like bump according to a first embodiment of the present invention.

3A to 3C are perspective views showing variations of different shapes of composite metal bumps in a wafer structure having gold-like bumps according to the first embodiment of the present invention.

Fig. 4 is a cross-sectional view showing a wafer structure having a gold-like bump according to a first embodiment of the present invention, which is pierced by a probe at the time of detection.

Fig. 5 is a cross-sectional view showing a wafer structure having a gold-like bump according to a first embodiment of the present invention when it is bonded to a lead.

Figure 6 is a partial cross-sectional view showing another wafer structure having gold-like bumps in accordance with a second embodiment of the present invention.

100. . . Wafer structure with imitation gold bumps

110. . . Wafer

111. . . Solder pad

112. . . The protective layer

113. . . surface

114. . . Opening

120. . . Under bump metal layer

121. . . Adhesive layer

122. . . Conductive layer

123. . . Side edge

130. . . Composite metal bump

151. . . Ontology

132. . . Joint

133. . . Upper surface

134. . . First outer side

135. . . Second outer side

140. . . Anti-substitute layer

Claims (12)

A wafer structure having a gold-like bump comprises: a wafer having a plurality of pads and a protective layer covering the surface of one of the wafers and forming a plurality of openings to expose the plurality of openings a solder pad; a bump under metal layer disposed on the pads and covering the periphery of the openings of the protective layer; a plurality of composite metal bumps, each composite metal bump being composed of a body Formed in a columnar shape with a joint portion, the system is aligned with the solder pads and disposed on the underlying metal layer of the bump, the joint portion is disposed on the body, wherein the system comprises not less than 99 wt% of silver (Ag) content, the material of the joint is selected from gold (Au), and the thickness of the joint is less than the thickness of the body; and an anti-dense layer is formed at the joint An upper surface and a first outer side and a second outer side of the body to completely cover the composite metal bumps, wherein the bulk of the composite metal bumps has a higher creep The latent change of the anti-potential layer. A wafer structure having a gold-like bump according to claim 1, wherein the first outer side of the joint and the second outer side of the body are flush with each other to form a pillar side wall. A wafer structure having a gold-like bump according to claim 2, wherein the under bump metal layer has a side edge not covered by the body, and the side edge is relatively recessed to the second outer side . A wafer structure having a gold-like bump according to claim 3, wherein a joint surface is formed between the body and the joint portion, and the joint surface is non-flat. The wafer structure having a gold-like bump according to claim 3, wherein the under bump metal layer has an adhesive layer and a conductive layer, the adhesive layer is attached to the solder pad, and the conductive layer is attached Attached to the adhesive layer. A wafer structure having a gold-like bump according to claim 5, wherein the anti-potential layer covers a side edge of the conductive layer to expose a side edge of the adhesive layer. A wafer structure having a gold-like bump according to the first aspect of the patent application, wherein the material of the anti-situ layer is selected from the group consisting of gold (Au), palladium (Pd), copper (Cu) and nickel (Ni). One. A wafer structure having a gold-like bump according to the first aspect of the patent application, wherein the anti-potential layer is selected from one of a replacement gold and a reduced gold to have oxidation resistance and high conductivity. A wafer structure having a gold-like bump according to claim 1, wherein the upper surface of the joint portion and the first outer side edge are angularly curved. The wafer structure having a gold-like bump according to the first aspect of the patent application, wherein the thickness of the body is between 6 μm and 20 μm, and the thickness of the joint portion is between 2 μm and 6 μm, and the thickness of the anti-situ layer is not More than 1μm. Wafer junction with gold bumps according to item 1 of the patent application scope The thickness of the joint is greater than the thickness of the anti-situ layer. The wafer structure having imitation gold bumps according to claim 1, wherein the composite metal bumps are selected from one of a cylinder, a cube, and a rectangular parallelepiped.