TWI718907B - Underboarding for laser boring of a printed circuit board - Google Patents

Abstract

A underboarding for laser boring of a printed circuit board is provided to prevent splashing of the undesired object during the boring process. The underboarding includes a bottom plate adhered to an area of a printed circuit board to be processed, a plurality of processing holes provided on the bottom plate and corresponding to a plurality of through-holes of the printed circuit board, and a plurality of vacuum holes extending through the top and bottom faces of the bottom plate.

Description

Backing plate for laser drilling of printed circuit board

The invention relates to a processing jig, in particular to a backing plate used for laser drilling of printed circuit boards that assists in positioning and prevents debris from sticking.

Please refer to Figure 1, which is a conventional printed circuit board laser drilling process. The tape-and-reel printed circuit board F is processed by a laser drilling machine. The content of the process is to process the entire roll of printed circuit The board F is gradually unfolded and pulled to position, and the target block on the printed circuit board F is fixed on a processing platform P, so that a laser drill D can drill a number of designated holes on the printed circuit board F, Each of the holes is used for conducting circuits between layers or for welding electronic parts.

The above-mentioned printed circuit board F is made of a flexible material as a substrate. The substrate has a metal material on both sides. The flexible material can be Polyimide (PI), and the metal material can be copper or tin. Or its alloy, the metal material is selected based on its conductivity and solderability. Because the conventional printed circuit board laser drilling process uses an instant high-density laser to drill the printed circuit board F, the above-mentioned The polymer layer and the metal layer form holes at high temperatures, and at the same time produce impurities such as slag and carbides. The impurities are likely to remain in the hole channels, or rebound and stick to the substrate surface around the hole, which causes difficulty and increase in subsequent processing. Process cost and other issues.

In view of this, the conventional laser drilling process for printed circuit boards does still have to be improved.

In order to solve the above-mentioned problems, the purpose of the present invention is to provide a backing plate for laser drilling of printed circuit boards, which can prevent drilling foreign bodies from remaining on the printed circuit board.

The second objective of the present invention is to provide a backing plate for laser drilling of printed circuit boards, which can fix the printed circuit board to assist drilling alignment.

Another object of the present invention is to provide a backing plate for laser drilling of printed circuit boards, which flatly unfolds the flexible circuit board to facilitate processing.

Another object of the present invention is to provide a backing plate for laser drilling of printed circuit boards, which can be used on both sides to improve work efficiency and save consumables.

The directionality described in the full text of the present invention or its similar terms, such as "upper (top)", "lower (bottom)", "inner", "outer", "surface", etc., mainly refer to the directions of the attached drawings, each Directionality or similar terms are only used to assist in describing and understanding the embodiments of the present invention, and are not used to limit the present invention.

The elements and components described in the full text of the present invention use the quantifiers "one" or "one" for convenience and to provide the general meaning of the scope of the present invention; in the present invention, it should be construed as including one or at least one, and single The concept of also includes the plural, unless it clearly implies other meanings.

The backing plate for laser drilling of a printed circuit board of the present invention includes: a bottom plate attached to an area to be processed of a printed circuit board, the printed circuit board having a plurality of through holes; a plurality of processing holes, the number The processing holes are blind holes, and the processing holes are on the upper and lower surfaces of the bottom plate and correspond to the through holes; and the plurality of vacuum holes are through holes that penetrate the upper and lower surfaces of the bottom plate.

Accordingly, in the backing plate for laser drilling of printed circuit boards of the present invention, by aligning the plurality of processing holes with the plurality of through holes to be processed, various foreign objects generated during the drilling process can enter To the channels of the several processing holes, and the depth of the several processing holes can prevent foreign matter from rebounding and staining The printed circuit board is adhered to the printed circuit board, and the plurality of vacuum holes are closely attached to the printed circuit board, the printed circuit board can be fixed to the bottom plate by vacuum suction, which can improve the accuracy of the drilling position, and the bottom plate can Continue drilling after turning over, which has the effect of improving work efficiency and saving consumables.

Wherein, the width of the bottom plate is greater than the width of the printed circuit board. In this way, the bottom plate can completely support the printed circuit board and vacuum-adsorb the processing area of the printed circuit board, which has the functions of convenient operation and auxiliary positioning.

Wherein, the diameter width of each processing hole is greater than the diameter width of each via hole, each via hole is aligned with the center of each processing hole, the diameter width of each processing hole is 50 microns to 100 microns, and the diameter of each via hole The diameter is 20 microns to 25 microns. In this way, the processing hole can completely contain the foreign matter dropped from the through hole, and has the effect of avoiding the foreign matter remaining on the printed circuit board.

Wherein, when the distance between the centers of two adjacent processing holes is less than 90 microns, the two processing holes merge to form a single groove. In this way, the via holes with similar distances can share the machining hole groove, which has the effect of ensuring the accommodating space of the machining hole and reducing the number of grooves.

Wherein, when the distance between the centers of two adjacent processing holes is greater than or equal to 90 microns, there is a gap between the two processing holes, and the gap is greater than or equal to 40 microns. In this way, the separation area between the plurality of processing holes has a sufficient width, and has the effect of maintaining the structural strength of the bottom plate to support the printed circuit board.

Wherein, the plurality of vacuum holes do not overlap with the plurality of processing holes and the plurality of via holes. In this way, it is possible to prevent foreign matter from falling into the suction hole and affecting the vacuum adsorption, and has the effect of stable adsorption to fix the printed circuit board.

Wherein, the diameter and width of each vacuum hole is 0.5 mm to 1.2 mm. In this way, the size of the vacuum hole can be adjusted according to the brushing of the circuit board, which has the effect of limiting the ratio of the hole area to maintain the flatness of the bottom plate.

Wherein, the bottom plate has a glass fiber board and a glass fiber board located on the surface of the glass fiber board. The copper film is not covered with the copper film on the surface of the glass fiber board in the range of the plurality of processing holes. In this way, each processing hole has the glass fiber board as the groove bottom and the copper film as the groove inner peripheral surface, which has the effect of quickly setting the processing hole and improving the alignment accuracy of the processing hole and the via hole.

Wherein, the thickness of the glass fiber board is 1.2 mm to 2 mm, and the film thickness of the copper film is 25 μm to 35 μm. In this way, the glass fiber board provides the mechanical strength of the bottom plate, and the depth of the processing hole can be adjusted by the film thickness of the copper film, which has the functions of arranging processing grooves and supporting the bottom plate to maintain flatness.

1: bottom plate

2: Machining hole

3: Vacuum hole

F: Printed circuit board

P: Processing platform

D: Laser drill

T: Via

S: gap

N1: Board thickness

N2: Film thickness

[Figure 1] The present invention is used in a laser drilling machine.

[Figure 2] A top view of the preferred embodiment of the present invention covering a printed circuit board.

[Figure 3] An enlarged view of the partial structure of Block A shown in Figure 2.

[Figure 4] A cross-sectional view of a preferred embodiment of the present invention.

In order to make the above and other objects, features, and advantages of the present invention more obvious and understandable, the preferred embodiments of the present invention are described below in detail with the accompanying drawings: please refer to Figures 1 and 2 It is shown that it is a preferred embodiment of the backing plate for laser drilling of printed circuit boards of the present invention. It includes a bottom plate 1, a plurality of machining holes 2 and a plurality of vacuum holes 3, the plurality of machining holes 2 and the A plurality of vacuum holes 3 are located on the bottom plate 1, a printed circuit board F is unfolded and positioned on the bottom plate 1, and the printed circuit board F covers the plurality of processing holes 2 and the plurality of vacuum holes 3.

The bottom plate 1 is fixed on the processing platform P of a laser drilling machine, and the roll-type printed circuit board F is unrolled and transported to the processing platform P by the roller of the laser drilling machine, so that the The area to be processed of the printed circuit board F is attached to the bottom plate 1. The width of the bottom plate 1 is preferably larger than the width of the printed circuit board F. The material of the bottom plate 1 can be glass fiber, which has high insulation, high temperature resistance and Good flatness and other characteristics enable the bottom plate 1 to withstand the high temperature of laser processing and to be suitable for supporting the printed circuit board F.

Please refer to Figures 2 and 3, the printed circuit board F has a plurality of through holes T, the distribution positions of the plurality of processing holes 2 correspond to the plurality of through holes T of the printed circuit board F, and each The opening of the processing hole 2 faces the printed circuit board F. In addition, the diameter width of each processing hole 2 is preferably larger than the diameter width of each via hole T, and it is preferable that when the printed circuit board F reaches the processing position, each of the conductive holes The hole T is aligned with the center of each machining hole 2, so that during the drilling of the plurality of via holes T, the debris generated can naturally fall into the groove formed by the plurality of machining holes 2, with Prevent foreign matter from remaining on the printed circuit board F.

In addition, the diameter width of each processing hole 2 can be 50 micrometers to 100 micrometers, and the diameter width of each via hole T can be 20 micrometers to 25 micrometers, when the distance between the centers of the two adjacent processing holes 2 is less than 90 microns. When micrometers, the two machining holes 2 can be combined into the same groove. As shown in Figure 3, consecutively several adjacent machining holes 2 can form a single elongated groove. When the distance between the centers of the machining holes 2 is greater than or equal to 90 microns, there may be a gap S between the two machining holes 2, and the gap S is preferably greater than or equal to 40 microns. The separation area between the formed grooves has sufficient width to provide supporting force. When the printed circuit board F is attached to the bottom plate 1 and covers the plurality of processing holes 2, the bottom plate 1 can maintain the printed circuit Flatness of plate F.

Please refer to Figure 4, each of the machining holes 2 can be a through hole or a blind hole. The present case is not limited to this. In this embodiment, the plurality of machining holes 2 are blind holes and are respectively provided on the bottom plate 1. On the upper and lower sides, two grooves with openings facing upward and downward are respectively formed at positions corresponding to the via holes T. In this way, when a long time drilling operation causes the plurality of processing holes 2 on the same surface to be deformed or filled When it is full of foreign objects, the bottom plate 1 can be turned over and the drilling operation can be continued, which has the effect of saving consumables.

In addition, the bottom plate 1 may be a composite board, which is composed of a glass fiber board and a copper film on the surface of the glass fiber board. The glass fiber board has a thickness N1, and the copper film has a film thickness N2. N1 is preferably 1.2 mm to 2 mm, and the film thickness N2 is preferably 25 micrometers to 35 micrometers. The base plate 1 can be formed by removing the copper film at a designated position through processes such as developing and etching to expose the glass fiber board at that position. The plurality of processing holes 2 make each processing hole 2 use the glass fiber board as the bottom of the groove, and the copper film as the inner circumferential surface of the groove, and the depth of each processing hole 2 is the film thickness N2. In this way, the present invention The backing plate can be manufactured by the same manufacturing process as the corresponding printed circuit board, which can be quickly prepared and improve the alignment accuracy of each processing hole 2 and each via hole T.

Please refer to Figures 3 and 4, the positions of the vacuum holes 3 correspond to the suction holes of the laser drilling machine. The diameter and width of each vacuum hole can be 0.5 mm ~ 1.2 mm. Preferably, the vacuum holes 3 do not overlap the plurality of processing holes 2 and the plurality of through holes T. Each vacuum hole 3 penetrates the through hole on the upper and lower surfaces of the bottom plate 1, so that the lower opening of each vacuum hole 3 can be Align the suction suction hole of the laser drilling machine, and the upper opening of each vacuum hole 3 faces the printed circuit board F and is closely attached to the flat part of the printed circuit board F, so that the suction suction hole can be The air between the bottom plate 1 and the printed circuit board F is extracted through the plurality of vacuum holes 3, so that the printed circuit board F can be closely attached and fixed to the bottom plate 1 by atmospheric pressure, thereby avoiding the deviation of the drilling position The role of.

The distribution positions of the processing holes 2 and the vacuum holes 3 on the bottom plate 1 of the present invention are matched with the circuit area of the printed circuit board F to be processed. Therefore, the backing plate of the present invention is specifically based on different printed circuits Various patterns of the board F are manufactured and used. When the printed circuit board F is fixed to the bottom plate 1 through the plurality of vacuum holes 3, the bottom plate 1 can be used to support and flatten the flexible tape-and-reel printed circuit board F, The drilling operation of the printed circuit board F can be accurately performed on the plurality of processing holes 2.

In summary, the backing plate for laser drilling of printed circuit boards of the present invention, by combining The plurality of processing holes are aligned with the plurality of through holes to be processed, so that various foreign objects generated during the drilling process can enter the channels of the plurality of processing holes, and the depth of the plurality of processing holes can prevent the foreign objects from rebounding. The printed circuit board is adhered to the printed circuit board, and the plurality of vacuum holes are closely attached to the printed circuit board, and the printed circuit board can be fixed to the bottom plate by vacuum suction, which can improve the accuracy of the drilling position.

Although the present invention has been disclosed using the above-mentioned preferred embodiments, it is not intended to limit the present invention. Anyone who is familiar with the art without departing from the spirit and scope of the present invention may make various changes and modifications relative to the above-mentioned embodiments. The technical scope of the invention is protected. Therefore, the scope of protection of the invention shall be subject to the scope of the attached patent application.

1: bottom plate

2: Machining hole

3: Vacuum hole

T: Via

S: gap

Claims (9)

A backing plate for laser drilling of a printed circuit board, comprising: a bottom plate attached to the area to be processed of a printed circuit board, the printed circuit board having a plurality of through holes; a plurality of processing holes, the plurality of processing The holes are blind holes, the plurality of processing holes are on the upper and lower sides of the bottom plate and correspond to each of the through holes; and the plurality of vacuum holes are through holes that penetrate the upper and lower surfaces of the bottom plate. Such as claim 1 for the backing plate for laser drilling of a printed circuit board, wherein the width of the bottom plate is greater than the width of the printed circuit board. For example, the backing plate for laser drilling of printed circuit boards according to claim 1, wherein the diameter width of each processing hole is greater than the diameter width of each via hole, each via hole is aligned with the center of each processing hole, each The diameter width of the processing hole is 50 micrometers to 100 micrometers, and the diameter width of each via hole is 20 micrometers to 25 micrometers. For example, the backing plate for laser drilling of printed circuit boards according to claim 3, wherein when the distance between the centers of two adjacent processing holes is less than 90 microns, the two processing holes merge to form a single groove. For example, the backing plate for laser drilling of printed circuit boards according to claim 3, wherein when the distance between the centers of two adjacent processing holes is greater than or equal to 90 microns, there is a gap between the two processing holes, The gap is greater than or equal to 40 microns. For example, the backing plate for laser drilling of printed circuit boards according to claim 1, wherein the plurality of vacuum holes do not overlap with the plurality of processing holes and the plurality of via holes. For example, the backing plate for laser drilling of printed circuit boards in claim 1, wherein the diameter and width of each vacuum hole is 0.5 mm ~ 1.2 mm. The pad for laser drilling of printed circuit boards as specified in any one of claims 1 to 7 The board, wherein the bottom plate has a glass fiber board and a copper film on the surface of the glass fiber board, and the surface of the glass fiber board in the range of the plurality of processing holes is not covered with the copper film. For example, the backing board for laser drilling of printed circuit boards in claim 8, wherein the glass fiber board has a thickness of 1.2 mm to 2 mm, and the copper film has a thickness of 25 micrometers to 35 micrometers.

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