Double-sided exposure device and method for high-density circuit boards

Abstract

The present invention discloses a double-sided exposure device and method for high-density circuit boards. The double-sided exposure device includes a workbench and a frame fixed on the workbench. The upper surface of the workbench is provided with an X-axis moving mechanism. The X-axis moving mechanism includes two grooves opened on the upper surface of the workbench and parallel to each other. Each of the grooves is provided with an X-axis linear module. The slide of each X-axis linear module is provided with a fixed plate. The upper surface of the fixed plate is provided with a circuit board rotating assembly and a Y-axis moving mechanism. The present invention can realize double-sided exposure of high-density circuit boards. After the front of the circuit board is exposed, the circuit board does not need to be removed. The circuit board can be turned over to realize exposure of the back of the circuit board. The circuit board fixing frame can realize rapid support and fixation of the circuit board. The mask plate fixing frame quickly installs the mask plate, thereby improving the working efficiency of circuit board exposure. The entire exposure equipment structure is simple and low-cost.

Description

Technical Field

[0001] The present invention relates to the technical field of circuit board manufacturing, and in particular to a double-sided exposure device and method for a high-density circuit board. Background Art

[0002] Exposure is an important step in the production process of printed circuit boards. Its principle is to use light technology to transfer the designed circuit pattern to the photosensitive material to prepare for the subsequent etching process. High-density circuit boards, namely HDI circuit boards, are becoming more and more widely used. They are a type of circuit board with a relatively high distribution density using micro-blind buried hole technology. For the exposure of high-density circuit boards, it is mainly to coat a layer of photosensitive film on the front and back of the high-density circuit board, place the designed circuit pattern on the photosensitive film, and use the exposure equipment to irradiate the photosensitive film to expose the circuit pattern on the surface of the high-density circuit board. After exposure, the high-density circuit board removes the unexposed part of the photosensitive film through processes such as development and etching. The remaining part is the designed circuit pattern. The carrier of the designed circuit pattern is called a mask plate, and the mask plate After the circuit pattern is exposed, it is exposed on the surface of the circuit board. There are three ways to place the mask plate and the high-density circuit board: the first is contact exposure, such as soft contact, hard contact and vacuum contact. The disadvantage is that the closer the contact, the greater the damage to the mask plate and the material; the second is proximity exposure, that is, a tiny gap is kept between the mask plate and the photosensitive film to avoid damage caused by direct contact between the mask plate and the photosensitive film, and the service life of the mask plate can be increased, and the circuit pattern exposure defects are small; the third is projection exposure, which refers to the use of an optical system to focus the light beam between the mask plate and the photosensitive film to achieve exposure. The disadvantage is that the equipment is more complex and expensive.

[0003] Existing equipment can only expose a single side of a high-density PCB. Exposure of the other side requires removing the PCB, flipping it over, repositioning it, and then exposing it again. This results in low exposure efficiency and cannot meet the production requirements of continuous exposure. Exposure equipment is generally complex and difficult to maintain, resulting in high equipment costs that need to be addressed urgently. Summary of the Invention

[0004] The purpose of the present invention is to overcome the deficiencies of the prior art and to provide a double-sided exposure device and method for high-density circuit boards, so as to solve the problems existing in the existing double-sided exposure devices for circuit boards.

[0005] The object of the present invention is achieved through the following technical solutions:

[0006] A double-sided exposure device for high-density circuit boards, comprising a workbench and a frame fixed to the workbench, wherein an X-axis moving mechanism is provided on the upper surface of the workbench, wherein the X-axis moving mechanism comprises two grooves formed on the upper surface of the workbench and parallel to each other, wherein each groove is provided with an X-axis linear module, and wherein a fixed plate is provided on the slide of each X-axis linear module; a circuit board rotating assembly and a Y-axis moving mechanism are provided on the upper surface of the fixed plate, wherein the Y-axis moving mechanism comprises a Y-axis linear module and a fixing frame for fixing the Y-axis linear module; wherein the circuit board rotating assembly comprises an L-shaped fixing plate, a rotating motor fixed to the vertical portion of the L-shaped fixing plate, and a circuit board fixing frame fixedly connected to the output shaft of the rotating motor; wherein the vertical portion of the L-shaped fixing plate is fixedly connected to the slide of the Y-axis linear module;

[0007] The circuit board holder is a hollow rectangular frame. Telescopic reels are provided on both inner side walls of the circuit board holder. A mesh roll for supporting the circuit board is installed inside the telescopic reel. The front end of the mesh roll is buckled with the circuit board holder. A distance measuring sensor is provided on the upper surface of the circuit board holder.

[0008] The frame is provided with a mask plate assembly, which includes an L-shaped fixing frame fixed to the frame, a fixing column connected to the L-shaped fixing frame, and a mask plate fixing frame movably connected to the fixing column. The mask plate fixing frame is a hollow rectangular frame composed of four right-angle blocks and two straight-line blocks. A spring is provided between one end of each right-angle block and the adjacent right-angle block, and a spring is provided between the other end of each right-angle block and the adjacent straight-line block. Each of the right-angle blocks and the straight-line blocks is provided with a step of the same height, and a fixing pin for fixing the mask plate is provided on the step.

[0009] An exposure light source is arranged on the top of the frame, and the mask plate fixing frame is located directly below the exposure light source.

[0010] The X-axis linear module is a ball screw linear module.

[0011] The Y-axis linear module is a synchronous belt linear module.

[0012] The opening direction of one of the telescopic reels is upward, and the opening direction of the other telescopic reel is downward.

[0013] The material of the mesh roll is carbon wire.

[0014] The fixing column and the mask plate fixing frame are connected by a movable pin.

[0015] The spring is a compression spring.

[0016] A CCD positioning camera is provided on the fixing plate.

[0017] A double-sided exposure method for high-density circuit boards, based on the above-mentioned double-sided exposure device, includes the following steps:

[0018] S1 provides a high-density circuit board, the opening direction is the bottom opening of the retractable reel mesh roll opened and buckled on the circuit board holder, the high-density circuit board is placed on the opened mesh roll, the opening direction is the top opening of the retractable reel mesh roll opened and buckled on the circuit board holder, the upper and lower layers of mesh roll to achieve the support and fixation of the high-density circuit board;

[0019] S2. Place the mask with through holes at the four corners in the mask holder. Depending on the size of the mask, pull the four right-angle blocks to fit the through holes of the mask onto the fixing pins to secure the mask.

[0020] S3. The X-axis linear module drives the high-density PCB to move along the X-axis. The CCD positioning camera identifies the position of the high-density PCB and controls the high-density PCB to reach the preset position.

[0021] S4. The Y-axis linear module drives the high-density PCB upward along the Y-axis. The distance sensor detects the distance between the PCB fixture and the mask fixture. The distance between the PCB fixture and the mask fixture is controlled between 200 and 400 microns.

[0022] S5. Turn on the exposure light source to expose the front of the high-density circuit board;

[0023] S6. After the high-density PCB is exposed on the front, the Y-axis linear module drives the PCB downward along the Y-axis, and the rotary motor drives the PCB holder to rotate 180 degrees. Repeat step S4, turn on the exposure light source, and expose the back of the high-density PCB.

[0024] S7. After the front and back surfaces of the high-density PCB are exposed, the X-axis linear module drives the high-density PCB to move along the X-axis, pushing one of the webs. The retractable web reel retracts the web and removes the high-density PCB.

[0025] The beneficial effects of the present invention are:

[0026] The present invention can achieve double-sided exposure of high-density circuit boards. After the front side of the circuit board is exposed, the circuit board does not need to be removed. Under the action of a rotating motor, the circuit board is driven to flip, and the back side of the circuit board can be exposed. The structure is simple and easy to operate, and the circuit board fixing frame can quickly support and fix the circuit board. The present invention adopts a close exposure method of the mask plate and the circuit board. The mask plate fixing frame can clamp and fix masks of different sizes. It is suitable for masks of different sizes. The mask plate can be quickly installed in the mask plate fixing frame, thereby improving the working efficiency of the circuit board exposure. The circuit board is driven by the Y-axis linear module and adopts a distance sensor to accurately control the distance between the circuit board and the mask plate. The entire exposure equipment structure is simple and low-cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a structural schematic diagram of the present invention;

[0028] Figure 2 It is a front view of the double-sided exposure device of the present invention;

[0029] Figure 3 is a side view of the double-sided exposure device of the present invention;

[0030] Figure 4 It is a structural schematic diagram of the circuit board rotating assembly in the present invention;

[0031] Figure 5 This is a schematic structural diagram of the mask plate fixing frame of the present invention;

[0032] In the figure, 1-workbench, 2-frame, 3-groove, 4-X-axial linear module, 5-fixed plate, 6-Y-axial linear module, 7-fixed frame, 8-L-shaped fixed plate, 9-rotating motor, 10-circuit board fixing frame, 11-retractable reel, 12-L-shaped fixing frame, 13-fixed column, 14-mask plate fixing frame, 15-right angle block, 16-linear block, 17-spring, 18-step, 19-fixing pin, 20-exposure light source. DETAILED DESCRIPTION

[0033] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings, but the protection scope of the present invention is not limited to the following.

[0034] like Figures 1 to 5As shown, a double-sided exposure device for high-density circuit boards includes a workbench 1 and a frame 2 fixed on the workbench 1, the upper surface of the workbench 1 is provided with an X-axis moving mechanism, the X-axis moving mechanism includes two grooves 3 opened on the upper surface of the workbench 1 and parallel to each other, each of the grooves 3 is provided with an X-axis linear module 4, and the slide of each X-axis linear module 4 is provided with a fixed plate 5; the upper surface of the fixed plate 5 is provided with a circuit board rotation assembly and a Y-axis moving mechanism, the Y-axis moving mechanism includes a Y-axis linear module 6 and a fixing frame 7 for fixing the Y-axis linear module 6, the circuit board rotation assembly includes an L-shaped fixing plate 8, a rotating motor 9 fixed to the vertical part of the L-shaped fixing plate 8 and a circuit board fixing frame 10 fixedly connected to the output shaft of the rotating motor 9, and the vertical part of the L-shaped fixing plate 8 is fixedly connected to the slide of the Y-axis linear module 6.

[0035] The circuit board fixing frame 10 is a hollow rectangular frame. A telescopic reel 11 is provided on both inner side walls of the circuit board fixing frame 10. A mesh roll for supporting the circuit board is installed in the telescopic reel 11. The front end of the mesh roll is buckled with the circuit board fixing frame 10. A ranging sensor is provided on the upper surface of the circuit board fixing frame 10.

[0036] A mask plate assembly is provided on the frame 2, and the mask plate assembly includes an L-shaped fixing frame 12 fixed on the frame 2, a fixing column 13 connected to the L-shaped fixing frame 12, and a mask plate fixing frame 14 movably connected to the fixing column 13. The mask plate fixing frame 14 is a hollow rectangular frame composed of four right-angle blocks 15 and two straight line blocks 16. A spring 17 is provided between one end of each right-angle block 15 and the adjacent right-angle block 15, and a spring 17 is also provided between the other end of each right-angle block 15 and the adjacent straight line block 16; each of the right-angle blocks 15 and the straight line block 16 is provided with a step 18 of the same height, and the step 18 is provided with a fixing pin 19 for fixing the mask plate.

[0037] An exposure light source 20 is disposed on the top of the frame 2 , and the mask fixing frame 14 is located directly below the exposure light source 20 .

[0038] The X-axis linear module 4 is a ball screw linear module.

[0039] The Y-axis linear module 6 is a synchronous belt linear module.

[0040] The opening direction of one of the telescopic reels 11 is upward, and the opening direction of the other telescopic reel 11 is downward.

[0041] The material of the mesh roll is carbon wire.

[0042] The fixing column 13 and the mask plate fixing frame 14 are connected by a movable pin.

[0043] The spring 17 is a compression spring.

[0044] The fixing plate 5 is provided with a CCD positioning camera.

[0045] A double-sided exposure method for high-density circuit boards, based on the above-mentioned double-sided exposure device, includes the following steps:

[0046] S1. Provide a high-density circuit board, pull open the mesh roll in the telescopic reel with the opening direction facing downward and buckle it onto the circuit board fixing frame, place the high-density circuit board on the pulled open mesh roll, pull open the mesh roll in the telescopic reel with the opening direction facing upward and buckle it onto the circuit board fixing frame, and the upper and lower layers of mesh rolls support and fix the high-density circuit board.

[0047] S2. Place the mask plate with through holes at the four corners in the mask plate fixing frame. According to the size of the mask plate, pull the four right-angle blocks to fit the through holes of the mask plate onto the fixing pins to complete the fixing of the mask plate.

[0048] The S3.X-axis linear module drives the high-density PCB to move along the X-axis. The CCD positioning camera identifies the position of the high-density PCB and controls the high-density PCB to reach the preset position.

[0049] S4. The Y-axis linear module drives the high-density PCB to move upward along the Y-axis direction. The distance sensor detects the distance between the PCB fixture and the mask fixture. The distance between the PCB fixture and the mask fixture is controlled between 200 and 400 microns.

[0050] S5. Turn on the exposure light source to expose the front side of the high-density circuit board.

[0051] S6. After the front side of the high-density PCB is exposed, the Y-axis linear module drives the PCB downward along the Y-axis, and the rotary motor drives the PCB holder to rotate 180 degrees. Repeat step S4, turn on the exposure light source, and expose the back side of the high-density PCB.

[0052] S7. After the front and back surfaces of the high-density PCB are exposed, the X-axis linear module drives the high-density PCB to move along the X-axis, pushing one of the webs. The retractable web reel retracts the web and removes the high-density PCB.

[0053] The present invention can achieve double-sided exposure of high-density circuit boards. After the front side of the circuit board is exposed, the circuit board does not need to be removed. Under the action of a rotating motor, the circuit board is driven to flip, and the back side of the circuit board can be exposed. The structure is simple and easy to operate, and the circuit board fixing frame can quickly support and fix the circuit board. The present invention adopts a close exposure method of the mask plate and the circuit board. The mask plate fixing frame can clamp and fix masks of different sizes. It is suitable for masks of different sizes. The mask plate can be quickly installed in the mask plate fixing frame, thereby improving the working efficiency of the circuit board exposure. The circuit board is driven by the Y-axis linear module and adopts a distance sensor to accurately control the distance between the circuit board and the mask plate. The entire exposure equipment structure is simple and low-cost.

[0054] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art will be able to modify the technical solutions described in the aforementioned embodiments or substitute equivalents for some of the technical features. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A double-sided exposure device for high-density circuit boards, characterized by: The invention comprises a workbench (1) and a frame (2) fixed on the workbench (1), wherein an X-axis moving mechanism is provided on the upper surface of the workbench (1), wherein the X-axis moving mechanism comprises two grooves (3) opened on the upper surface of the workbench (1) and parallel to each other, wherein an X-axis linear module (4) is provided in each groove (3), and a fixed plate (5) is provided on the slide of each X-axis linear module (4); a circuit board rotating assembly and a Y-axis moving mechanism are provided on the upper surface of the fixed plate (5), wherein the Y-axis moving mechanism comprises a Y-axis linear module (6) and a fixed frame (7) for fixing the Y-axis linear module (6), wherein the circuit board rotating assembly comprises an L-shaped fixed plate (8), a rotating motor (9) fixed to the vertical part of the L-shaped fixed plate (8), and a circuit board fixing frame (10) fixedly connected to the output shaft of the rotating motor (9), wherein the vertical part of the L-shaped fixed plate (8) is fixedly connected to the slide of the Y-axis linear module (6); The circuit board fixing frame (10) is a hollow rectangular frame. A telescopic reel (11) is provided on both inner side walls of the circuit board fixing frame (10). A mesh roll for supporting the circuit board is installed in the telescopic reel (11). The front end of the mesh roll is buckled with the circuit board fixing frame (10). A distance measuring sensor is provided on the upper surface of the circuit board fixing frame (10). A mask plate assembly is provided on the frame (2), and the mask plate assembly comprises an L-shaped fixing frame (12) fixed on the frame (2), a fixing column (13) connected to the L-shaped fixing frame (12), and a mask plate fixing frame (14) movably connected to the fixing column (13); the mask plate fixing frame (14) is a hollow rectangular frame composed of four right-angle blocks (15) and two straight-line blocks (16); a spring (17) is provided between one end of each right-angle block (15) and an adjacent right-angle block (15); and a spring (17) is also provided between the other end of each right-angle block (15) and an adjacent straight-line block (16); each right-angle block (15) and straight-line block (16) is provided with a step (18) of the same height, and a fixing pin (19) for fixing the mask plate is provided on the step (18); An exposure light source (20) is provided on the top of the frame (2), and the mask plate fixing frame (14) is located directly below the exposure light source (20).

2. The double-sided exposure device for high-density circuit boards according to claim 1, characterized in that: The X-axis linear module (4) is a ball screw linear module.

3. The double-sided exposure device for high-density circuit boards according to claim 1, characterized in that: The Y-axis linear module (6) is a synchronous belt linear module.

4. The double-sided exposure device for high-density circuit boards according to claim 1, characterized in that: The opening direction of one of the telescopic reels (11) is upward, and the opening direction of the other telescopic reel (11) is downward.

5. The double-sided exposure device for high-density circuit boards according to claim 1, characterized in that: The material of the mesh roll is carbon wire.

6. The double-sided exposure device for high-density circuit boards according to claim 1, characterized in that: The fixing column (13) and the mask plate fixing frame (14) are connected by a movable pin.

7. The double-sided exposure device for high-density circuit boards according to claim 1, characterized in that: The spring (17) is a compression spring.

8. The double-sided exposure device for high-density circuit boards according to claim 1, characterized in that: A CCD positioning camera is provided on the fixing plate (5).

9. A double-sided exposure method for high-density circuit boards, based on the double-sided exposure device according to any one of claims 1 to 8, characterized in that: The following steps are involved: S1 provides a high-density circuit board, the opening direction is the bottom opening of the retractable reel mesh roll opened and buckled on the circuit board holder, the high-density circuit board is placed on the opened mesh roll, the opening direction is the top opening of the retractable reel mesh roll opened and buckled on the circuit board holder, the upper and lower layers of mesh roll to achieve the support and fixation of the high-density circuit board; S2. Place the mask with through holes at the four corners in the mask holder. Depending on the size of the mask, pull the four right-angle blocks to fit the through holes of the mask onto the fixing pins to secure the mask. S3. The X-axis linear module drives the high-density PCB to move along the X-axis. The CCD positioning camera identifies the position of the high-density PCB and controls the high-density PCB to reach the preset position. S4. The Y-axis linear module drives the high-density PCB upward along the Y-axis. The distance sensor detects the distance between the PCB fixture and the mask fixture. The distance between the PCB fixture and the mask fixture is controlled between 200 and 400 microns. S5. Turn on the exposure light source to expose the front of the high-density circuit board; S6. After the high-density PCB is exposed on the front, the Y-axis linear module drives the PCB downward along the Y-axis, and the rotary motor drives the PCB holder to rotate 180 degrees. Repeat step S4, turn on the exposure light source, and expose the back of the high-density PCB. S7. After the front and back surfaces of the high-density PCB are exposed, the X-axis linear module drives the high-density PCB to move along the X-axis, pushing one of the webs to move. The retractable web reel then retracts the web to remove the high-density PCB.

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