EP3659408A1

EP3659408A1 - Method, device and installation for producing printed circuit boards

Info

Publication number: EP3659408A1
Application number: EP18740745.7A
Authority: EP
Inventors: Christian Schmid
Original assignee: Gebrueder Schmid GmbH and Co
Current assignee: Gebrueder Schmid GmbH and Co
Priority date: 2017-07-26
Filing date: 2018-06-29
Publication date: 2020-06-03
Also published as: KR20200030111A; KR20230156815A; KR102685303B1; DE102017212887A1; US20200221579A1; TW201922073A; JP7438100B2; US11963306B2; JP2020528219A; KR102674414B1; TWI783015B; WO2019020318A1; US20240155773A1; JP2023182826A; CN111133846A

Abstract

In a method for producing printed circuit boards, a substrate (112), which has a carrier layer made of an electrically insulating material and an electrically conductive layer applied thereto, is processed in a plurality of steps. To carry out a development step and/or an etching step, the substrate (112) is rotated. A developer solution and/or an etching liquid is applied to the rotating substrate (112) by means of at least one nozzle (113). In addition to the method, a device suitable for carrying out the method and an installation comprising the device are described.

Description

Method. Device and system for printed circuit board production

The invention described below relates to a method for manufacturing printed circuit boards while processing a substrate which has a carrier layer made of an electrically insulating material and an electrically conductive layer applied thereto.

A printed circuit board (PCB) serves as a carrier for electronic components and ensures their electrical contact. Almost every electronic device contains one or more printed circuit boards.

Printed circuit boards comprise a flat carrier layer having a front and a rear side, which consists of an electrically insulating material, as well as on the carrier layer located conductor tracks for making electrical contact with the electronic components. For example, fiber-reinforced plastic, plastic films or hard paper can serve as insulating material. The tracks are usually made of a metal.

In the simplest case, only one side of the carrier layer is provided with conductor tracks. However, more complex circuits often require more than one trace level. In these cases, both sides of a carrier layer may be provided with conductor tracks. The interconnects of the two interconnect levels are then usually electrically connected via vias. For this purpose, for example, holes can be drilled in the carrier layer and the borehole walls can be metallized.

In the printed circuit board production, the starting substrate used is a substrate which, in addition to the carrier layer made of the electrically insulating material, has an electrically conductive layer applied thereon, from which the printed conductors are formed. This is done in a multi-stage photolithographic process using a photoresist, whose solubility in a developer solution by means of radiation, in particular by means of UV radiation, can be influenced.

In a typical procedure for the formation of the conductor tracks, the electrically conductive layer of the starting material is covered with a layer of the photoresist. The layer of the photoresist can for example be laminated onto the electrically conductive layer of the starting material. Subsequently, the layer of the photoresist is exposed in an exposure step of said radiation, wherein portions of the layer are protected by means of an exposure mask from radiation exposure. Depending on the photoresist used and the developer solution used, either the exposed or unexposed portions of the photoresist layer are soluble in the developer solution after the exposure step and may be removed in a subsequent step. In this subsequent step, the development step, portions of the electrically conductive layer of the starting material are exposed, which can be removed in a further subsequent step, an etching step, wet-chemically. The remaining remnants of the electrically conductive layer form the desired interconnect structure. If necessary, it can be uncovered and, for example by galvanic deposition of a suitable metal, further strengthened in a deposition step.

After each chemical treatment, the substrate is usually treated in a rinsing step with a rinsing medium, for example, ultrapure, deionized water. Optionally, the rinsing step is followed by a drying step before the substrate is subjected to the next processing step.

The multistage photolithographic processes and, in particular, the etching, rinsing and deposition steps subsequent to the development step can in principle be carried out either as part of a batch process or as part of an inline process.

In the batch process, the substrate to be processed is treated successively in several basins, each containing different chemical treatment media. If necessary, the substrate can be automatically transferred from one to the next basin, but during the individual treatments its position is usually not changed. It does not move continuously along a process line.

On the other hand, inline procedures ensure a tighter schedule. In these, the substrate to be processed is moved substantially continuously along a process line. Inline methods are therefore often referred to as a continuous process. In most cases, it is conveyed in a flow belt over a roller field, where it is subjected to variable chemical and physical conditions in successive, not strictly delimited treatment sections of the process line, without having to leave the roller field. An example of such a section is shown in Fig. 2 of DE 10 2005 011 298 AI. However, it is also possible lent to fix the substrate in a holding device and to move the holding device along the process line. A role field is not mandatory in this case.

From DE 10 2009 049 905 AI a suitable holding device is known. The holding device comprises a rectangular frame in which the printed circuit boards can be fixed. On two outer longitudinal sides of the frame transport carriages are arranged, by means of which the holding device can be transported along the process line, wherein treatment sections are passed, in which cleaning or etching steps or optionally also coatings by deposition of metals are performed. Particularly advantageous is the use of such a holding device in the production of very thin circuit boards.

Inline processes have the great advantage over batch processes that replacement of used treatment and rinsing media can be carried out without problems continuously and without interrupting the process. However, there are also disadvantages. Due to the linear process management, the substrate to be processed passes through devices, for example nozzles, with which the substrate is sprayed with an etching liquid along the process line exactly once. In many cases, in order to achieve the desired etching result, many nozzles have to be installed, which are successively passed from the substrate, which can greatly increase the cost of etching equipment and thus equipped processing lines. Reducing the speed at which the substrate passes the nozzles would be a viable alternative. However, this is not an expedient measure, especially in the case of etching and development steps, which are often a bottleneck anyway in a process line.

The object of the invention was to provide an optimized procedure for printed circuit board production, which is characterized in particular by improvements in etching and development steps.

To achieve this object, the invention proposes the method with the features mentioned in claim 1, the device with the features mentioned in claim 7 and the system with the features mentioned in claim 14. Further developments of the invention are the subject of dependent claims.

An inventive method is used for printed circuit board production. This results in the processing of a substrate which has a carrier layer of an electrically insulating material and an electrically conductive layer applied thereto (hereinafter also referred to as printed circuit board substrate designated). The processing of the substrate comprises some or all of the following processing steps:

Chemical or electrical deposition of metallic layers on the substrate in a metallization step

Introduction of holes in the substrate in a drilling step

By contacting the holes introduced into the substrate in a contacting step

Applying a layer of a photoresist to the electrically conductive layer in a covering step

Exposure of the photoresist using an exposure mask in an exposure step Removing exposed or unexposed areas of the layer from the photoresist exposing the electrically conductive layer in areas in a development step

Removing the exposed portions of the electrically conductive layer in an etching step

Cleaning the substrate in a rinse step

Drying the substrate in a drying step,

Optionally, the method may include further, not listed here processing steps. Some of the steps mentioned can also be repeated, for example, the rinsing step and the drying step, which can be followed by both the development step and the etching step, for example.

Within the scope of the former steps, in particular the drilling step, the contacting step, the capping step and the exposure step, the method according to the invention does not differ from known methods. However, differences may arise with regard to the development step, the etching step or even both steps. Furthermore, differences may also arise with regard to the rinsing step and / or the drying step.

In particular, the method according to the invention is characterized in that the substrate for rotating the development step and / or the etching step is rotated and a developer solution and / or an etching liquid is applied to the rotating substrate by means of at least one nozzle. In short, both the development step and the etching step and both steps can be performed with a rotating substrate. This approach brings with it a whole series of advantages. Due to the rotation, individual regions of the substrate not only pass through the area of action of the nozzle once but several times. The nozzle used can thus be used more efficiently than the nozzles in the initially discussed linear process control. To achieve the same process result, consequently, much fewer nozzles are required, which in turn makes it possible to economically represent the use of very high-quality, expensive nozzles. A modification of the etching liquids and developer solutions used is not required, it can be used the same chemicals that are used in classical etching and development steps. Regardless, surprisingly significantly reduced chemical turnover was observed in comparative studies. And since the application of developer solution and / or etching liquid to the rotating substrate can be carried out in a comparatively space-saving manner, significantly less exhaust air is produced.

The method can be carried out particularly advantageously if the substrate is arranged in an annular carrier frame which is set in rotation together with the substrate. It is possible to fix the substrate directly in the support frame. However, it can also be fixed first in a rectangular frame of a holding device, which is then arranged together with the substrate in the annular support frame. This can be particularly useful when the substrate for upstream processing steps, for example, for treatment steps that take place in a process line operated in a continuous process, anyway must be fixed in the holding device.

It is particularly preferred in the context of the presently described method to process rectangular printed circuit boards, in particular with the following dimensions:

Thickness: 1 μm to 10 mm

Length: up to 700 mm

Width: up to 700 mm

Particularly preferably, the substrate is transferred to carry out the development step and / or the etching step in a treatment chamber. In this one of the steps but also both steps can be performed one after the other. Preferably, the substrate is rotated in the treatment chamber by means of a drive system which can exert a tangential force on the annular support frame.

In principle, the development step and / or the etching step can be performed on both a horizontally and a vertically oriented substrate. In particularly preferred embodiments, however, the substrate in the treatment chamber is aligned vertically, in particular together with the annular support frame. The development step and / or the etching step are then performed on the vertically oriented rotating substrate.

At the beginning, it has been pointed out that for more complex circuits PCBs with more than one PCB level are required. The inventive method is also suitable for the production of such printed circuit boards. For this purpose, a substrate is processed, in which the carrier layer has a front side and a rear side, to each of which an electrically conductive layer is applied. Such a substrate is also referred to below as a substrate coated on both sides.

In the present invention, it is preferable in these cases if the front side and the back side of the substrate are simultaneously subjected to the development step and / or the etching step, in particular in the treatment chamber. Particularly preferably, the front side is sprayed by means of a first nozzle with the developer solution and / or the etching liquid while at the same time the rear side is sprayed by means of a second nozzle with the developer solution and / or the etching liquid.

The simultaneous processing of the front and the back is particularly advantageous in the mentioned vertical orientation of the substrate. Horizontal processing may cause puddling on the upper side of a flat substrate. This can result in different processing results. In vertical processing, however, sprayed on developer solution or etching liquid can run evenly. The treatment intensity can be kept the same for the front and the back.

In particularly preferred embodiments, in addition to the etching step, an immediately upstream and / or an immediately following rinsing step and / or In addition to the development step, an immediately upstream and / or an immediately following rinsing step in the treatment chamber are performed. As known from the prior art, deionized water is preferably used as the flushing medium here.

With particular advantage, in addition to one of the rinsing steps, an immediately following drying step can also be carried out in the treatment chamber.

Both the additional rinsing steps and the additional drying steps can be carried out simultaneously on the front and the back of the substrate when processing a double-coated substrate, such as the development and / or the etching step. For this purpose, a plurality of nozzles may be provided, with which the front and the back can be acted upon simultaneously with a flushing medium and / or compressed air.

From the above, it will be understood that a whole number of processing steps performed in in-line processes along a process line in successive processing sections may be carried out in one and the same processing chamber according to the method described herein. For example, the substrate can be successively transferred into the treatment chamber and rotated,

Developer solution are applied to the rotating substrate,

cleaning the rotating substrate with a rinsing medium,

the cleaned, rotating substrate is treated with an etching liquid, and

the rotating substrate after the treatment with the etching liquid again with the

Rinsing medium to be cleaned.

In particularly preferred embodiments, the process according to the invention is characterized by one or both of the following steps:

The substrate is discharged to carry out the development step and / or the etching step from a process line operated in a continuous process or in a batch process.

Subsequent to performing the development step and / or the etching step, the substrate is introduced into a process line operated in a continuous process or in a batch process. For example, it may be preferable to carry out the capping step and the exposing step in different treatment sections of an in-line process and to discharge the substrate for carrying out the development step and the etching step as well as an intermediate and a subsequent step of the etching step rinsing step from the process line. Optionally, subsequent steps, for example a final drying step, can be carried out again as an inline process.

In principle, however, it is also conceivable, if appropriate even preferred, to carry out the drying step in the treatment chamber on the rotating substrate.

It is particularly advantageous if the developer solution and / or the etching liquid are applied to the rotating substrate by means of a movable nozzle. Preferably, the nozzle is attached to this purpose on an arm.

In preferred embodiments, the position of the nozzle relative to the axis of rotation of the rotating substrate is varied in performing the development step and / or the etching step. For this purpose, as will be explained below, the nozzle may for example be attached to a pivotable and / or a displaceable arm, so that the variation of the position of the nozzle can be effected by a pivoting movement and / or a displacement of the arm. This has the advantage that each point on the substrate can be sprayed vertically from above, which ensures an optimal and uniform spray effect.

Alternatively, it would also be possible to apply the developer solution and / or the etching liquid to the rotating substrate by means of a plurality of stationary nozzles whose position differs relative to the axis of rotation of the rotating substrate. However, this process variant is less preferred.

In principle, the flushing medium, like the developer solution and the etching liquid, can be applied to the substrate via the movable nozzle. In preferred embodiments, however, the flushing medium is applied to the rotating substrate by means of the plurality of immovable nozzles whose position relative to the rotational axis of the rotating substrate differs in each case after completion of the development step and / or the etching step. The nozzles are preferably mounted in a row on a support arm for this purpose. The plurality of stationary nozzles may also serve to dry-blow the substrate after completion of the rinse step. For this purpose, they can be coupled, for example, with a compressed air source.

The device according to the invention is particularly suitable for carrying out the method according to the invention and is distinguished by the following features:

It has a drive system with which the substrate can be set in rotation, or is coupled to such a system, and

it has the at least one nozzle with which the developer solution and / or the etching liquid can be applied to the rotating substrate.

As a nozzle, in preferred embodiments, an ultrasonic nozzle may be used, which comprises an ultrasonic generator in addition to an outlet for the liquid to be applied. The generated ultrasound is transferred to the substrate via the liquid emerging from the nozzle and can considerably accelerate etching and development processes.

Particularly preferably, the device comprises a housing which encloses an interior, in which there is a receptacle for the substrate to be treated. The interior of the housing with the receptacle may serve as the above-mentioned treatment chamber.

As mentioned above, it may be advantageous to fix the substrate in a holding device during the method according to the invention. Furthermore, it may be advantageous to position the substrate or the holding device together with the substrate fixed therein in an annular carrier frame before it is set in rotation to carry out the development step and / or the etching step. The annular support frame may in this case be part of the device or introduced as a removable frame each with a substrate to be treated in the device.

If the annular support frame is part of the device, then the annular support frame itself may have the receptacle for the substrate to be treated. A substrate to be treated can first be fixed in the holding device, which is then positioned in the receptacle in the annular support frame. Alternatively, the substrate to be treated may be fixed directly in the receptacle in the annular support frame. If the annular support frame is introduced as a removable frame each with a substrate to be treated in the device, the receptacle is preferably designed for rotatably supporting the annular support frame in the device.

When using the annular support frame, the device - regardless of whether the annular support frame is part of the device or not - in preferred embodiments, a plurality of rollers and / or waves on which the edge of the rotated annular support frame can roll.

Furthermore, when using the annular support frame, it is preferred that the device comprises at least one drive shaft capable of exerting on the edge of the annular support frame a tangential force to set the support frame in rotation.

In a preferred embodiment, the device comprises said at least one drive shaft and, in addition, two or three guide rollers for maintaining the annular support frame in the plane of rotation. The guide rollers and also the at least one drive shaft can be mounted sprung here.

Both the at least one drive shaft and the guide rollers may have circumferential recesses, in particular circumferential groove-like depressions, in which the edge of the rotationally offset annular support frame can roll.

Particularly preferably, the drive shaft and the guide rollers are positioned in the interior space such that the edge of a ring-shaped support frame positioned vertically in the interior can roll on the shaft and the guide rollers during rotation.

The drive system of the device according to the invention preferably comprises the mentioned drive shaft. Furthermore, the drive system may comprise a motor and possibly a drive unit for coupling the motor to the drive shaft.

The at least one nozzle, with which the developer solution and / or the etching liquid can be applied to the rotating substrate, is preferably movable, in particular pivotable or displaceable, mounted. You can this particular attached to a pivoting or sliding arm his. But it is also possible, for example, to store the at least one nozzle slidably in a rail.

In preferred embodiments, the apparatus comprises a further drive system adapted to pivot or displace the pivotable or displaceable arm or to displace the nozzle displaceably mounted in the rail, or is coupled to such a drive system.

In particularly preferred embodiments, the apparatus includes an electronic control unit coupled to both drive systems and capable of coordinating the mechanical actions of the drive systems, such as adjusting the speed at which the substrate rotates to the speed at which the nozzle is pivoted ,

In particularly preferred embodiments, the device according to the invention comprises at least two nozzles, with which developer solution and / or etching liquid can be applied to the rotating substrate, wherein the nozzles are arranged within the device such that in a substrate coated on both sides whose front side and its rear side are covered simultaneously by the nozzles can be sprayed. For example, a first of the nozzles may be arranged to spray the front of the substrate while a second of the nozzles spray the back of the substrate. It is preferred that each of the nozzles is attached to a pivotable or displaceable arm.

For this purpose, the device particularly preferably has a double arm with two respectively pivotable or displaceable arms, to each of which at least one of the nozzles is attached. In principle, the two arms can be independently pivotable or displaceable. Preferably, however, the two arms are fixed to a common pivot axis and aligned parallel to each other, so that the arms and the nozzles attached thereto perform each pivotal movement together.

The arms of the double arm are preferably spaced apart from one another such that the annular support frame together with the substrate can rotate between them. The nozzles attached to the arms are preferably aligned such that their spray direction is directed perpendicular to the rotating substrate. As a rule, the device according to the invention is coupled to an etching liquid reservoir and / or a developer solution reservoir, from which the etching liquid and / or the developer solution can be transported to the at least one nozzle. Optionally, the device can also be coupled with a flushing medium conveying means, can be transported from the flushing medium in the device, possibly also to the nozzle.

In some preferred embodiments, the device has its own etchant delivery means and / or developer solution delivery means which can deliver developer solution and / or an etchant from an etchant reservoir and / or developer solution reservoir to the nozzle. Optionally, the device also has flushing medium conveying means with which flushing means can be transported to the nozzle.

From the above statements, it is already implicit that the nozzle is coupled in preferred embodiments to the etching liquid reservoir and / or to the developer solution reservoir and optionally to the flushing medium reservoir.

In a particularly preferred embodiment, the nozzle and the etching liquid reservoir and the developer solution reservoir via at least one valve, in particular a multi-way valve, coupled to each other. The multi-way valve locks in a first switching position the transport path for etching liquid to the nozzle and opens the transport path for developer solution to the nozzle. In a second switching position, it opens the transport path for etching liquid to the nozzle and blocks the transport path for developer solution to the nozzle. If, in addition, the flushing medium reservoir is coupled to the nozzle, in particular via the multiway valve in a third switching position, in which only the transport path for flushing medium is open to the nozzle, so the nozzle and of course the substrate between development and etching processes can be cleaned with flushing medium become.

However, the movable nozzle is not necessarily needed for cleaning the substrate. Rather, it is preferred if the device in addition to the movable nozzle also has a plurality of immovable nozzles whose position relative to the axis of rotation of the rotating substrate differs in each case and which are coupled to the flushing medium reservoir. The cleaning of the substrate can thus also be done by means of these immovable nozzles.

It may further be preferred that the device has a plurality of immovable nozzles whose position relative to the axis of rotation of the rotating substrate is different in each case and with a compressed air source are coupled. Through these nozzles, the substrate can be subjected to a drying step.

In preferred embodiments, the device has a plurality of immovable nozzles whose position relative to the rotational axis of the rotating substrate differs in each case and which are coupled to both the flushing medium reservoir and the compressed air source, preferably also here via a multi-way valve, the access to the flushing medium reservoir and the compressed air source can selectively lock.

The immovable nozzles may, for example, be mounted in a row on an immovable, rigidly fixed arm, which is aligned parallel to a surface of the rotating substrate to be treated, so that all the nozzles are equidistant from the surface.

Particularly preferably, the device has an outlet for used etching liquid and / or used developer solution and / or used flushing medium. This outlet is usually located at the lowest point of the housing. The outlet may be coupled to a multi-way valve to supply the liquids to be discharged to their respective destination. Thus, the interior of the housing can be connected via the multi-way valve in a first switching position with a container for used developer solution and in a second switching position with a container for used etching liquid. Of course, it is also conceivable to feed the developer solution in a circulatory process back to the developer solution reservoir and / or the etching liquid in a circulation process again the etching liquid reservoir.

It is further preferred that the treatment chamber is coupled to an exhaust air system.

In preferred embodiments, the device may comprise tempering means for heating or cooling the etching solution and / or the developer solution to a desired application temperature prior to their application.

Each system for printed circuit board production, which comprises the device described, is also the subject of the present invention.

As is already implicitly evident from the above statements, such a system can, in addition to the described device, also comprise, in particular, modules in which treatment steps in the Passing process or be carried out in a batch process, so for example modules in which the covering step and the exposure step are carried out in a continuous process.

Further features, details and advantages of the invention will become apparent from the claims and the abstract, the wording of which is incorporated by reference into the content of the description, the following description of preferred embodiments of the invention and with reference to the drawings.

Hereby show:

FIG. 1 schematically shows an annular carrier frame which can be used in the proposed method, including a square printed circuit board substrate fixed therein and a movable nozzle attached to a pivotable arm for applying etching liquid and / or developer solution to the substrate (top view from above); and

Figure 2 shows schematically an arrangement comprising a drive shaft and a plurality of rollers and nozzles, which are grouped for the purpose of performing a development step and / or etching step according to the invention around a fixed in an annular support frame of Figure 1 PCB substrate (perspective view obliquely from the front). and

Figure 3a shows schematically a device proposed by the invention comprising the arrangement shown in Figure 2 in a vertical orientation in a housing. and

Figure 3b is a plan view of the forward facing side of the device shown in Figure 3a; and

Figure 3c is a plan view of the rearwardly facing side of the device shown in Fig. 3a.

The annular support frame 110 shown in FIG. 1 has a central receptacle 111 which is defined by a square frame 110a and in which a square printed circuit board substrate 112 is fixed. The square frame 110a, in turn, is framed by an outer ring 110b and is fixedly connected to it by a plurality of struts, including the struts 110c and HOd. A movable nozzle 113 is located at the bottom of the tip of the pivotable arm 114, which is attached to a pivot axis (not visible here) coupled to the drive unit 115. By pivoting the arm 114, the movable nozzle 113 is allowed to act along the circular line 116 on the printed circuit substrate 112. With simultaneous rotation of the annular support frame 110 and the printed circuit board substrate 112 fixed therein, with the movable nozzle 113, depending on the pivot position, each point on the printed circuit substrate 112 can be detected and sprayed perpendicular to the plane of the printed circuit substrate 112.

The arrangement shown in Fig. 2 comprises the drive shaft 117 and the guide rollers 118 and 119 which form a receptacle for the annular support frame 110 shown in FIG. 1, together with the printed circuit board substrate 112 fixed therein. The drive shaft 117 is coupled via the drive unit 120 to a motor (not shown) which drives the drive shaft 117. Both the drive shaft 117 and the guide rollers 118 and 119 have circumferential groove-like recesses in which the edge HOe of the rotated annular support frame 110 can roll. Good visible is approximately the circumferential groove 119e in the guide roller 119. The guide roller 118, for example by means of a pivoting arm or a spring (not shown here) against the edge HOe be pressed. As the drive shaft 117 rotates, it exerts a tangential force on the abutting edge HOe of the annular support frame 110 and rotates the support frame 110 together with the substrate 112 therein.

On the pivot axis 121, the pivotable arms 114 and 122 are attached, to each of which a nozzle is fixed, with which the printed circuit board substrate 112 can be sprayed with etching liquid or with a developer solution. The pivotable arms 114 and 122 together with the pivot axis form a double arm. The arms 114 and 122 are in this case aligned parallel to each other and move synchronously. With the nozzles attached to them, the surfaces of the printed circuit substrate 112 may each be sprayed vertically from above, such as the surface 112a of the printed circuit substrate by means of the movable nozzle 113 attached to the arm 114. If the nozzle 113 and the printed substrate 112 were each rigid and immovable, the area of action of the nozzle 113 would be limited to the spray cone 123. However, since the circuit board substrate 112 rotates in the treatment and the nozzle 113 is pivotable, each dot on the surface 112a may be sprayed with the nozzle 113. The same applies to the lower side of the printed circuit board substrate 112, which is not shown here. This can be detected at any point by the nozzle attached to the arm 122.

On two immovable, mutually parallel arms 124 and 125, which can be fixed, for example, on the housing of a device according to the invention, are each five nozzles in one Row attached. By means of these nozzles, the printed circuit board substrate 112 can be sprayed with a flushing medium. For example, the surface 112a may be detected by the nozzle 127a, whose area of effect is limited to the spray cone 128. The underside of the printed circuit board substrate 112, not shown here, can be detected, for example, by the nozzles 126a, 126b and 126c. The distances of the nozzles attached to the arms are such that the areas of action of adjacent nozzles, such as nozzles 126b and 126c, overlap. Although the arms 124 and 125 are not pivotally formed, each point of the surfaces of the rotating circuit board substrate 112 may be detected by the nozzles.

In preferred embodiments, the arrangement comprises a plurality of immovable nozzles 126a, 126b and 126c whose position relative to the axis of rotation of the rotating substrate 112 is different and which are coupled to both the flushing medium reservoir and the compressed air source, preferably also here a multi-way valve that can selectively block access to the flushing medium reservoir and the compressed air source.

The immovable nozzles may, for example, be mounted in a row on an immovable, rigidly fixed arm which is aligned parallel to a surface of the rotating substrate 112 to be treated so that all the nozzles are equidistant from the surface.

The apparatus 130 shown in FIG. 3 a comprises the transparent housing 129 and the arrangement shown in FIG. 2 in vertical alignment, which is arranged in the interior defined by the housing 129. The printed circuit board substrate 112 can be rotated vertically in this case and sprayed with etching liquid or developer solution.

The housing 129 has the slot-shaped inlet 129a, through which the annular support frame 110 arranged inside the housing 129, together with the printed circuit board substrate 112 fixed therein, can be removed after the treatment has been completed. The inlet 129a may be closed to seal the housing.

At the lowest point of the housing 129 is the outlet 129b. This outlet is coupled to a multi-way valve (not shown) for delivering the liquids to be discharged to their respective destination. In a first switching position, the valve connects the interior of the housing 129 with a container for used developer solution and in a second switching position with a container for used etching liquid. The illustrated device is not shown for reasons of clarity with all its functional parts. For example, there are no supply lines for etching liquid and developing solutions, fastening means and electrical components for driving the drive shaft 117 and the drive unit 115.

Shown is, however, the pivot arm 131, with which the guide roller 118 can be pressed against the edge of the annular support frame 110.

In Fig. 3b is a plan view of the forward facing side of the device shown in Fig. 3a is shown in Fig. 3c is a plan view of the rearwardly facing side of the device shown in Fig. 3a.

Claims

claims

A method of manufacturing printed circuit boards by processing a substrate (112) comprising a support layer of an electrically insulating material and an electrically conductive layer deposited thereon, wherein the processing of the substrate (112) comprises some or all of the processing steps of the group a. Chemical or electrical deposition of metallic layers on the substrate (112) in a metallization step,

b. Introducing bores into the substrate (112) in a drilling step,

c. Contacting the holes made in the substrate (112) in a contacting step,

d. Applying a layer of a photoresist to the electrically conductive layer in a covering step,

e. Exposing the photoresist using an exposure mask in an exposure step,

f. Removing exposed or unexposed areas of the layer from the photoresist, exposing the electrically conductive layer in areas in a development step, g. Removing the exposed portions of the electrically conductive layer in an etching step, h. Cleaning the substrate (112) in a rinsing step and

i. Drying the substrate (112) in a drying step, characterized in that i. the substrate (112) is rotated to perform the developing step and / or the etching step, and a developing solution and / or an etching liquid is applied to the rotating substrate by means of at least one nozzle (113).

2. The method of claim 1 with at least one of the following additional features: a. The substrate (112) is placed in an annular support frame (110) which is rotated together with the substrate (112).

b. The substrate (112) is fixed in a rectangular frame of a holding device, which is arranged together with the substrate (112) in the annular support frame (110). c. The substrate (112) is transferred to a processing chamber for performing the development step and / or the etching step. d. In the treatment chamber, the substrate (112) is rotated by means of a drive system (117, 120) capable of exerting a tangential force on the annular support frame (110).

e. The substrate (112) is vertically aligned in the treatment chamber.

3. The method according to any one of claims 1 or 2 with at least one of the following additional features: a. The substrate (112) comprises a carrier layer having a front and a back, to each of which an electrically conductive layer is applied.

b. The front side and the back side of the substrate (112) are simultaneously subjected to the development step and / or the etching step, in particular in the treatment chamber.

c. The front side is sprayed by means of a first nozzle with the developer solution and / or the etching liquid and the backside is sprayed by means of a second nozzle with the developer solution and / or the etching liquid.

4. The method according to any one of the preceding claims with at least one of the following additional features: a. In addition to the etching step, an immediately preceding and / or immediately following rinsing step is also carried out in the treatment chamber.

b. In addition to the development step, an immediately preceding and / or immediately following rinsing step is also carried out in the treatment chamber.

c. In addition to one of the rinsing steps, an immediately following drying step is also carried out in the treatment chamber.

5. The method according to any one of the preceding claims with at least one of the following additional features: a. The substrate (112) is discharged to carry out the development step and / or the etching step from a process line operated in a continuous process or in a batch process.

b. The substrate (112), after performing the development step and / or the etching step, is introduced into a process line operated in a continuous process or in a batch process.

Method according to one of the preceding claims, having at least one of the following additional features: a. The developer solution and / or the etching liquid is applied to the rotating substrate (112) by means of at least one movable nozzle (113).

b. The position of the at least one nozzle (113) relative to the rotational axis of the rotating substrate is varied in performing the development step and / or the etching step, in particular by a pivoting movement or displacement of the arm (114) or a displacement of the nozzle (113).

c. By means of a plurality of immovable nozzles (126a, 126b, 126c) whose position relative to the axis of rotation of the rotating substrate (112) differs in each case, a flushing medium is applied to the rotating substrate (112) after completion of the development step and / or the etching step.

d. By means of a plurality of immovable nozzles (126a, 126b, 126c) whose position relative to the axis of rotation of the rotating substrate (112) differs in each case, the substrate (112) is blown dry after completion of the rinsing step.

Device for producing printed circuit boards by processing a substrate (112) which has a carrier layer of an electrically insulating material and an electrically conductive layer applied thereto, in particular according to a method according to one of the preceding claims, having the features a. the device has a drive system (117, 120) to which the substrate (112) can be rotated, or is coupled to such a system, and b. the device has at least one nozzle (113), with which developer solution and / or an etching liquid can be applied to the rotating substrate (112).

Apparatus according to claim 7, having the following additional feature: a. the device has a housing 129 which serves as a treatment chamber and encloses an interior in which there is a receptacle (111) for the substrate (112) to be treated.

Apparatus according to claim 7 or claim 8, having at least one of the following additional features: a. The receptacle (111) is designed for the rotatable mounting of an annular support frame in which the substrate is arranged.

b. The device comprises an annular support frame (110) with a receptacle for the substrate (112).

c. The device comprises a plurality of rollers and / or shafts (117, 118, 119) on which the edge of the rotated annular support frame can roll. d. The device comprises at least one drive shaft capable of exerting on the edge (HOe) of the annular support frame a tangential force to set the support frame (110) in rotation.

e. The device comprises two or three guide rollers for holding the annular support frame in the plane of rotation.

10. Device according to one of claims 7 to 9 with at least one of the following additional features: a. The nozzle (113), with which the developer solution and / or the etching liquid can be applied to the rotating substrate, is movably mounted.

b. The movable nozzle (113) is mounted pivotably or displaceably.

c. The movable nozzle (113) is attached to a pivotable or displaceable arm. d. The movable nozzle is slidably mounted in a rail.

11. Device according to one of claims 7 to 10 with at least one of the following additional features: a. The nozzle (113) is coupled to an etchant reservoir and to a developer solution reservoir and optionally to a purge medium reservoir.

b. The nozzle (113) and the etching liquid reservoir and the developer solution reservoir are coupled to one another via a multi-way valve which blocks the transport path for etching liquid to the nozzle in a first switching position and opens the transport path for developer solution to the nozzle and in a second switching position The etchant transfer path to the nozzle opens, blocking the developer solution transport path to the nozzle.

12. Device according to one of claims 7 to 11 with at least one of the following additional features: a. The device has a plurality of immovable nozzles (126a, 126b, 126c) whose position relative to the axis of rotation of the rotating substrate (112) differs, respectively, and which are coupled to a flushing medium reservoir.

b. The apparatus has a plurality of immovable nozzles (126a, 126b, 126c) whose position relative to the axis of rotation of the rotating substrate is different in each case and which are coupled to a compressed air source.

13. Device according to one of claims 7 to 12 with the following additional feature: a. The device has an outlet 129b for used etching liquid and / or used developer solution and / or used flushing medium.

14. System for printed circuit board production comprising a device for printed circuit board production with the features of one of claims 7 to 13.