CN109413848B

CN109413848B - Method for processing copper-aluminum combined metal substrate

Info

Publication number: CN109413848B
Application number: CN201811235420.2A
Authority: CN
Inventors: 张亚锋; 何艳球; 张宏; 张永谋; 蒋华; 叶锦群
Original assignee: Victory Giant Technology Huizhou Co Ltd
Current assignee: Victory Giant Technology Huizhou Co Ltd
Priority date: 2018-10-23
Filing date: 2018-10-23
Publication date: 2020-04-21
Anticipated expiration: 2038-10-23
Also published as: CN109413848A

Abstract

The invention provides a processing method of a copper-aluminum combined metal substrate, wherein the copper-aluminum combined metal substrate is used for manufacturing a thermoelectric separation plate and comprises a first copper foil layer, an insulating layer, a copper plate, an aluminum plate and an aluminum plate protective film which are sequentially laminated from top to bottom; the method comprises the following steps: tearing off the protective film of the aluminum plate on the copper-aluminum combined metal substrate; superposing a PP sheet and a second copper foil layer under the high-temperature adhesive tape, wherein the second copper foil layer is positioned under the PP sheet and then pressed; removing the copper foil corresponding to the laser grooving or laser drilling position during the manufacturing of the thermoelectric separation plate on the first copper foil layer by adopting an alkaline etching mode; performing laser grooving or laser drilling on the insulating layer; then electroplating is carried out; and after the electroplating is finished, uncovering and tearing off the laminated high-temperature adhesive tape, the pp sheet and the second copper foil layer.

Description

Method for processing copper-aluminum combined metal substrate

Technical Field

The invention relates to the field of circuit boards, in particular to a method for processing a copper-aluminum combined metal substrate for a thermoelectric separation circuit board.

Background

The most common heat sink material for the metal substrate of the PCB is copper or aluminum alloy. Aluminum alloys are also the most used materials because of their ease of processing and low cost. In contrast, copper has better instantaneous heat absorption capacity than aluminum alloy, but dissipates heat at a slower rate than aluminum alloy. Considering the respective shortcomings of copper and aluminum, the LED headlamp and the mining machine accelerating chip of a high-end automobile in the market part at present adopt a new copper-aluminum combined metal substrate for heat dissipation. By virtue of higher heat conductivity coefficient, the copper base can quickly absorb heat released by the heating device, and the aluminum base block can provide a larger heat storage space and quickly release heat.

The copper-aluminum alloy base plate structure comprises a copper foil layer, a dielectric layer, a copper base layer and an aluminum alloy layer. Because the medium layer has poor heat dissipation effect, in order to achieve better heat dissipation effect, the medium layer below the heating device can be cut out, so that the heating device is directly contacted with the copper base layer or directly adopts a laser mode to open holes below the heating device, and then the holes are filled with copper in an electroplating mode to form heat-conducting copper columns with the copper base.

In the processing process, when copper is deposited on the copper-aluminum composite substrate before electroplating, the copper is deposited on the aluminum-based surface protective film, the copper film is easy to fall off, copper slag is easy to form and adheres to the normal copper foil surface, and only the single-side copper foil conductive capacitor is easy to burn during subsequent electroplating, so that the quality is influenced. If the aluminum base surface protective film is removed and then passes through the copper deposition line, the aluminum base surface has the risk of polluting the liquid medicine, so a new production process needs to be developed.

Disclosure of Invention

Aiming at the problems, the invention provides a processing method of a copper-aluminum combined metal substrate, wherein the copper-aluminum combined metal substrate is used for manufacturing a thermoelectric separation plate and comprises a first copper foil layer, an insulating layer, a copper plate, an aluminum plate and an aluminum plate protective film which are sequentially laminated from top to bottom; the method comprises the following steps: tearing off the protective film of the aluminum plate on the copper-aluminum combined metal substrate; superposing a PP sheet and a second copper foil layer under the high-temperature adhesive tape, wherein the second copper foil layer is positioned under the PP sheet and then pressed; removing the copper foil corresponding to the laser grooving or laser drilling position during the manufacturing of the thermoelectric separation plate on the first copper foil layer by adopting an alkaline etching mode; performing laser grooving or laser drilling on the insulating layer; then electroplating is carried out; and after the electroplating is finished, uncovering and tearing off the laminated high-temperature adhesive tape, the pp sheet and the second copper foil layer.

Preferably, after the pressing, a first drilling is performed, and a tool hole is drilled at the edge of the copper-aluminum combined metal substrate.

Further, after electroplating, firstly manufacturing a circuit pattern on the first copper foil layer, and then sequentially performing solder mask, characters, gold melting and secondary drilling; and the secondary drilling is to drill a hole in the plate of the copper-aluminum combined metal substrate, and the cover is uncovered after the formation and the test are carried out after the secondary drilling.

According to the processing method of the copper-aluminum combined metal substrate, the aluminum plate is protected by removing the aluminum plate protective film, then pasting the high-temperature glue, and pressing the PP sheet and the copper foil, the aluminum plate is pressed in the plate, the copper foil is arranged on both sides of the copper-aluminum combined metal substrate after pressing, the problems of copper slag deposition, scorching of an electroplating plate, copper nodules and incapability of filling blind holes cannot be caused, and the problem of aluminum-based pollution liquid medicine cannot be caused; the high-temperature adhesive tape is used as a protective isolation layer, PP residual glue can be prevented from polluting the aluminum surface during pressing, later uncovering is facilitated, the high-temperature adhesive tape on the aluminum surface is uncovered after forming and testing, and the finished copper-aluminum combined metal substrate can be obtained.

Drawings

Fig. 1 is a schematic structural view of a copper-aluminum bonded metal substrate.

Fig. 2 is a press-fit structure diagram of an embodiment of the processing method of the copper-aluminum combined metal substrate provided by the invention.

Detailed Description

The present invention will be described in detail with reference to examples.

In specific implementation, as shown in fig. 1, the copper-aluminum combined metal substrate for manufacturing the thermoelectric separation plate includes a first copper foil layer 1, an insulating layer 2, a copper plate 3, an aluminum plate 4, and an aluminum plate protective film 5, which are sequentially stacked from top to bottom.

When the method is implemented, the copper-aluminum combined metal substrate is cut, and then the aluminum plate protective film on the copper-aluminum combined metal substrate is torn off; and a PP sheet 7 and a second copper foil layer 8 are superposed under the high-temperature adhesive tape, and the second copper foil layer is positioned under the PP sheet and then pressed.

And after pressing, drilling a first hole, and drilling a tool hole on the edge of the copper-aluminum combined metal substrate.

Then removing the copper foil corresponding to the laser slotting or laser drilling position during the manufacturing of the thermoelectric separation plate on the first copper foil layer by adopting an alkaline etching mode; and then correspondingly performing laser grooving or laser drilling on the insulating layer to prepare for subsequent electroplating and copper deposition to form the heat-conducting column.

Electroplating is carried out, a heat conducting column is formed at the laser slotting or laser drilling position, and copper foils are arranged on the two sides of the copper-aluminum combined metal substrate after pressing, so that the problems of copper slag deposition, burning of electroplating plate edges, incapability of filling copper nodules and blind holes and no aluminum-based pollution liquid medicine are solved; after electroplating, firstly manufacturing a circuit pattern on the first copper foil layer, and then sequentially performing solder mask, characters, gold melting and secondary drilling; and the second drilling is to drill holes in the plate of the copper-aluminum combined metal substrate. And (5) after the second drilling, forming and testing, uncovering, and tearing off the laminated high-temperature adhesive tape, the pp sheet and the second copper foil layer.

The above-mentioned embodiments only express the embodiments of the present invention, and the description is more specific and detailed, but not understood as the limitation of the patent scope of the present invention, but all the technical solutions obtained by using the equivalent substitution or the equivalent transformation should fall within the protection scope of the present invention.

Claims

1. A copper-aluminum combined metal substrate is used for manufacturing a thermoelectric separation plate and comprises a first copper foil layer, an insulating layer, a copper plate, an aluminum plate and an aluminum plate protective film which are sequentially laminated from top to bottom; it is characterized by comprising: tearing off the protective film of the aluminum plate on the copper-aluminum combined metal substrate; superposing a PP sheet and a second copper foil layer under the high-temperature adhesive tape, wherein the second copper foil layer is positioned under the PP sheet and then pressed; removing the copper foil corresponding to the laser grooving or laser drilling position during the manufacturing of the thermoelectric separation plate on the first copper foil layer by adopting an alkaline etching mode; performing laser grooving or laser drilling on the insulating layer; then electroplating is carried out; and after the electroplating is finished, uncovering and tearing off the laminated high-temperature adhesive tape, the pp sheet and the second copper foil layer.

2. The method for processing the copper-aluminum combined metal substrate as recited in claim 1, wherein: and after pressing, drilling a first hole, and drilling a tool hole on the edge of the copper-aluminum combined metal substrate.

3. The method for processing the copper-aluminum combined metal substrate as recited in claim 2, wherein: after electroplating, firstly manufacturing a circuit pattern on the first copper foil layer, and then sequentially performing solder mask, characters, gold melting and secondary drilling; and the secondary drilling is to drill a hole in the plate of the copper-aluminum combined metal substrate, and the cover is uncovered after the formation and the test are carried out after the secondary drilling.