Method for reducing pool effect during etching of ceramic substrate product

Abstract

The invention discloses a method for reducing the pool effect during etching of a ceramic substrate product. According to the method for reducing the pool effect during etching of the ceramic substrate product, a flow guide groove is formed in a copper foil process edge, the two ends, in the length direction, of the flow guide groove penetrate through the copper foil process edge, and the flow guide groove right faces the corner area of a pattern unit adjacent to the current copper foil process edge. According to the method, the old etching waste liquid is discharged in time through the diversion grooves, so that the problem of non-uniform bottom spacing or poor wiring during thick copper foil pattern etching is solved.

Description

Technical Field

[0001] The invention relates to the field of semiconductor technology, in particular to an etching method for a ceramic substrate. Background Art

[0002] In the post-etching process of copper-clad ceramic substrate (DCB), the sintered DCB substrate semi-finished product needs to be etched with etching liquid to obtain the required copper foil pattern. For details, see the structure before etching. Figure 3 , place the dry film A, copper foil B and ceramic plate C from top to bottom. The ideal structure after etching is shown in Figure 4 , copper foil B is etched according to the window of dry film A. Since the copper foil of DCB substrate is relatively thick, between 300 microns and 1200 microns, the bottom pool effect of product spacing is obvious during etching, the old etching liquid is not fully exchanged, and the activity is low, resulting in poor etching effect, uneven bottom spacing or poor connection, causing product scrapping. Figure 5 .

[0003] The reason for this defect is that the copper foil is relatively thick. During the etching process, a graphic unit 11 is formed, and a copper foil process edge 13 is formed on the periphery of the graphic unit. The spacing between adjacent graphic units 11, that is, the product spacing 12, the more etching is done to the bottom, the more old etching liquid is accumulated in the spacing. Since there is a closed copper foil process edge 13 at the outlet of the product spacing 12, it can be seen that Figure 6 , which blocks the timely discharge of the etching waste liquid, and the fresh etching solution cannot reach the bottom, resulting in poor etching effect. The current solution is to increase the etching spray pressure and increase the fluidity of the etching solution, but it only has a certain effect on thin copper foil, but has no obvious effect on thick copper products, and the size of the spacing at the top will be too large. Summary of the invention

[0004] In view of the problems existing in the prior art, the present invention provides a method for reducing the pool effect during etching of ceramic substrate products to solve at least one of the above technical problems.

[0005] In order to achieve the above-mentioned purpose, the present invention provides a method for reducing the pool effect during etching of ceramic substrate products, characterized in that a guide groove is opened on the copper foil process edge, both ends of the guide groove in the length direction pass through the copper foil process edge, and the guide groove is directly opposite to the corner area of ​​the graphic unit adjacent to the current copper foil process edge.

[0006] The guide groove of the invention allows old etching waste liquid to be discharged in time through the groove, thereby solving the problem of uneven bottom spacing or poor connection when etching thick copper foil patterns.

[0007] Further preferably, the included angle between the length direction of the guide grooves provided on each copper foil process edge and the length direction of the corresponding copper foil process edge is 20°.

[0008] Further preferably, the included angle in the length direction of the guide grooves opened on adjacent copper foil process edges is 90°.

[0009] Further preferably, the guide groove is arranged along the length direction of the copper foil process edge, and the guide groove divides the copper foil process edge into sub-units arranged along the length direction of the copper foil process edge;

[0010] The corner of the subunit adjacent to the guide groove is a transition rounded structure.

[0011] Further preferably, the radius of the transition fillet structure is 1 mm.

[0012] Further preferably, the etched ceramic substrate product includes a copper foil layer and a ceramic layer arranged on the upper and lower sides, and the copper foil layer includes a graphic area and a process edge area arranged inside and outside;

[0013] The graphic area is a graphic unit arranged in a matrix;

[0014] The process edge area is a copper foil process edge surrounding the periphery of the graphic area, and the process edge area includes a front process edge, a rear process edge, a left process edge and a right process edge;

[0015] The guide groove provided on the front process side is the front groove;

[0016] The guide grooves provided on the back process side are back grooves;

[0017] The guide groove provided on the left process side is the left groove;

[0018] The guide groove provided on the right process side is the right groove;

[0019] The length direction of the front groove is parallel to the length direction of the rear groove;

[0020] The length direction of the left groove is parallel to the length direction of the right groove.

[0021] Further preferably, the left end of the front process edge, the left end of the left process edge and the left end of the rear process edge are flush;

[0022] The right end of the rear process edge, the right end of the right process edge, and the right end of the front process edge are flush.

[0023] Further preferably, the width of the guide groove is twice the spacing between the graphic units.

[0024] Further preferably, the midpoint of the guide groove on one side adjacent to the graphic unit is located on the center line of the interval between two adjacent graphic units.

[0025] Further preferably, during the etching, the dry film layer, the copper foil layer and the ceramic layer are arranged from top to bottom;

[0026] The dry film layer is provided with a first grid-shaped window for etching the spacing of the graphic units, a second strip-shaped window for etching the process edge of the copper foil, and a third strip-shaped window for etching the guide grooves;

[0027] The inner side of the second strip-shaped window is connected to and conducted with the second grid-shaped window;

[0028] The outer side of the second strip-shaped window is connected to and conducted with the third strip-shaped window.

[0029] Beneficial effects:

[0030] The present invention can realize timely discharge of old etching waste liquid through the diversion groove, and solve the problem of water pool effect at the bottom of product spacing. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 A structural schematic diagram of the present invention;

[0032] Figure 2 It is a partial enlarged view of the guide groove of the present invention;

[0033] Figure 3 A schematic diagram of a structure before etching of the background technology;

[0034] Figure 4 A schematic diagram of a structure after etching of the background technology;

[0035] Figure 5 It is a structural schematic diagram of the pool effect in the background technology.

[0036] Figure 6 It is a structural schematic diagram of a product in the background technology. DETAILED DESCRIPTION

[0037] The present invention will be further described below in conjunction with the accompanying drawings.

[0038] See also Figure 1 as well as Figure 2, Specific embodiment 1: A method for reducing the pool effect in etching ceramic substrate products, by opening a guide groove 14 on the copper foil process edge 13, the two ends of the guide groove 14 in the length direction penetrate the copper foil process edge 13, and the guide groove 14 is directly opposite to the corner area of ​​the graphic unit adjacent to the current copper foil process edge. The guide groove of the present invention allows the old etching waste liquid to be discharged in time through the groove, solving the problem of uneven bottom spacing or poor connection when etching thick copper foil graphics.

[0039] The included angle between the length direction of the guide grooves provided on each copper foil process edge and the length direction of the corresponding copper foil process edge is 20°.

[0040] The included angle of the guide grooves opened on the adjacent copper foil process edges in the length direction is 90°.

[0041] The guide groove is arranged along the length direction of the copper foil process edge, and the guide groove divides the copper foil process edge into sub-units arranged along the length direction of the copper foil process edge; the corner of the sub-unit adjacent to the guide groove side is a transition fillet structure.

[0042] The radius R of the transition fillet structure is 1 mm.

[0043] The etched ceramic substrate product includes a copper foil layer and a ceramic layer arranged above and below, the copper foil layer includes a graphic area and a process edge area arranged inside and outside; the graphic area is a graphic unit arranged in a matrix; the process edge area is a copper foil process edge arranged around the graphic area, and the process edge area includes a front process edge, a rear process edge, a left process edge and a right process edge; the guide grooves opened on the front process edge are front grooves; the guide grooves opened on the rear process edge are rear grooves; the guide grooves opened on the left process edge are left grooves; the guide grooves opened on the right process edge are right grooves; the length direction of the front groove is parallel to the length direction of the rear groove; the length direction of the left groove is parallel to the length direction of the right groove.

[0044] The left end of the front process edge, the left end of the left process edge, and the left end of the rear process edge are flush; the right end of the rear process edge, the right end of the right process edge, and the right end of the front process edge are flush.

[0045] The width of the guide groove is twice the spacing of the graphic units. The midpoint of the guide groove on the side adjacent to the graphic unit is located on the center line of the spacing between the two adjacent graphic units. The spacing between the guide groove on the side adjacent to the graphic unit is b. The spacing c between the two ends of the guide groove on the side adjacent to the graphic unit and the center line of the spacing between the two adjacent graphic units is equal to the spacing a between the two adjacent graphic units.

[0046] During etching, the dry film layer, the copper foil layer and the ceramic layer are arranged from top to bottom; the dry film layer is provided with a first grid-shaped window for etching the spacing of the graphic units, a second strip-shaped window for etching the process edge of the copper foil and a third strip-shaped window for etching the guide groove; the inner side of the second strip-shaped window is connected to the second grid-shaped window; the outer side of the second strip-shaped window is connected to the third strip-shaped window.

[0047] The width of the first grid-shaped window is smaller than the width of the graphic unit spacing, and the difference is 0.3 mm.

[0048] The width of the third strip window is smaller than the width of the guide groove, and the difference is 0.3 mm.

[0049] The above are only preferred embodiments of the present invention. It should be pointed out that, for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for reducing the pool effect in etching ceramic substrate products, characterized in that: A guide groove is opened on the copper foil process edge, both ends of the guide groove in the length direction penetrate the copper foil process edge, and the guide groove faces the corner area of ​​the graphic unit adjacent to the current copper foil process edge.

2. A method for reducing the pool effect during etching of ceramic substrate products according to claim 1, characterized in that: The included angle between the length direction of the guide grooves provided on each copper foil process edge and the length direction of the corresponding copper foil process edge is 20°.

3. The method for reducing the pool effect during etching of ceramic substrate products according to claim 1, characterized in that: The included angle of the guide grooves opened on the adjacent copper foil process edges in the length direction is 90°.

4. The method for reducing the pool effect during etching of ceramic substrate products according to claim 1, characterized in that: The guide groove is arranged along the length direction of the copper foil process edge, and the guide groove divides the copper foil process edge into sub-units arranged along the length direction of the copper foil process edge; The corner of the subunit adjacent to the guide groove is a transition rounded structure.

5. The method for reducing the pool effect during etching of ceramic substrate products according to claim 4, characterized in that: The radius of the transition fillet structure is 1 mm.

6. The method for reducing the pool effect during etching of ceramic substrate products according to claim 1, characterized in that: The etched ceramic substrate product includes a copper foil layer and a ceramic layer arranged on the upper and lower sides, and the copper foil layer includes a graphic area and a process edge area arranged inside and outside; The graphic area is a graphic unit arranged in a matrix; The process edge area is a copper foil process edge surrounding the periphery of the graphic area, and the process edge area includes a front process edge, a rear process edge, a left process edge and a right process edge; The guide groove provided on the front process side is the front groove; The guide grooves provided on the back process side are back grooves; The guide groove provided on the left process side is the left groove; The guide groove provided on the right process side is the right groove; The length direction of the front groove is parallel to the length direction of the rear groove; The length direction of the left groove is parallel to the length direction of the right groove.

7. A method for reducing the pool effect during etching of ceramic substrate products according to claim 6, characterized in that: The left end of the front process edge, the left end of the left process edge and the left end of the rear process edge are flush; The right end of the rear process edge, the right end of the right process edge, and the right end of the front process edge are flush.

8. The method for reducing the pool effect during etching of ceramic substrate products according to claim 6, characterized in that: The width of the guide groove is twice the spacing between the graphic units.

9. The method for reducing the pool effect during etching of ceramic substrate products according to claim 6, characterized in that: The midpoint of the guide groove on one side adjacent to the graphic unit is located on the center line of the interval between two adjacent graphic units.

10. The method for reducing the pool effect during etching of ceramic substrate products according to claim 1, characterized in that: During etching, the dry film layer, copper foil layer and ceramic layer are set from top to bottom; The dry film layer is provided with a first grid-shaped window for etching the spacing of the graphic units, a second strip-shaped window for etching the process edge of the copper foil, and a third strip-shaped window for etching the guide grooves; The inner side of the second strip-shaped window is connected to and conducted with the second grid-shaped window; The outer side of the second strip-shaped window is connected to and conducted with the third strip-shaped window.

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