TW486791B - Method for improving adhesion between encapsulation material and circuit substrate having a solder resist layer - Google Patents

Abstract

A method for improving adhesion between an encapsulation material and a circuit substrate having a solder resist comprises: using a permanganate encapsulation residue removal process to roughen the surface of the circuit substrate having a solder resist layer. In another preferred embodiment according to the present invention, the surface roughening step of the circuit substrate having a solder resist layer can be accomplished by a plasma encapsulation residue removal process, a sand spraying process, or a brush polishing process.

Description

V. Description of the invention G) [Field of the invention] board, which is particularly used to form the adhesion between the circuit boards used to form the electronic package structure: T kinds of improved sealant plastic and has a solder resist layer: based [previously technology】

The base structure generally includes more than one active device on an I semiconductor wafer. Structure, f! ":, a package made of germanium arsenide or gallium arsenide (SCM), which contains two components, called a single chip: (then). The electronic seal, cover, Α device structure "Ran is a multi-chip package." The device structure generally has a piece of gel to seal the main body, go to the second side, and provide insulation. The sealant generally uses the conventional casting method such as transfer molding (tr_ "〇ldlng); to seal the plastic; placed in a film cavity of a mold. The substrate generally contains a layer of conductive material (usually copper). Or plated with solder: ':' Carry on a dielectric layer (usually glass fiber reinforced epoxy tree). A circuit substrate has two layers of conductive circuits (conductor circuits), which are called double-layer substrates. In order to accommodate more circuits in a farm board, several layers of conductive circuits are generally sandwiched into a multilayer substrate.丨 $ The conventional circuit substrate manufacturing process includes: (A) laminating a conductive metal layer on both sides of a dielectric layer in a conventional manner. (B) forming a via in the substrate Or through-hole, and through conventional methods such as electrodeless piating in the via hole

486791 V. Description of the invention (2) Or the through hole is coated with a layer of conductive metal. (C) Photolithography and etching are used to form the desired conductive circuit in the conductive metal layer. ^ On the substrate's solder resist—Ie solder resist) coating surface ’, transfer the desired pattern, and then develop to form it; a good material such as gold or palladium is electroplated on the unprotected layer and W force layer. In step ⑻, the drilling process will leave: the film is covered with conductive metal (smear) agricultural holes, because these slags will cause je ^ abUity problem, so it must be removed in electrodeless plating 仃 刖. At present, there are several types of slag removal process systems ^: There are several mechanical or chemical slag removal methods disclosed in the United States ::: Know. For example, 4 / 01,783. A common process for removing glue residue is to remove the resin glue edge, which is disclosed in the US patent. Generally, since the surface of the sealing compound and the circuit substrate is substantially flat, the sealing compound and the anti-glow film are square; : =, (Bonding mechanism) is almost only a mechanism of chemical interlocking (mechanic interlock), so under the environment (such as pressure pin test (pressure c〇〇k = wet ring = between the interface is vulnerable to water) The invasion will form a delamination between the macroscopic upper sealant and the anti-knock film. [Summary of the Invention] The present invention therefore provides an improved sealant plastic and a circuit with a solder resist POO-161, ptd No. 5 Page 4 ^ 6791 V. Description of the invention (3) The method and technical problem of adhesion between substrates, thereby overcoming or at least improving the aforementioned prior art. According to the invention, the improved sealing plastic and the circuit substrate with a solder resist layer are improved. In the meantime, a method including roughening the surface of a circuit board with a perforate-repellent layer using a permanganate slag-removing process. The high-potrate slag-removing process mainly includes the following steps: , Different kinds of solutions are processed sequentially, these solutions The sequence is a swelling solution (such as die thy 1 ene glycol monobuty 1 ej her), an empirical solution and a neutralizing solution (such as an inorganic acid X /, a neutral oxalic acid salt) The solution can also be replaced by qualitative re-acid acid trip> Valley fluid. In other preferred embodiments of the present invention, the roughening step of the circuit substrate with a solder resist layer can be performed by an electric paddle slag removal process, spraying The sand process or the brush grinding process is achieved. Since the solder mask layer on the circuit substrate surface is rough after passing through the surface roughening surface, the adhesion at the solder mask layer / sealing gel interface has been improved. There is also a mechanical interlocking mechanism. Because the mechanical interlocking mechanism has the property of being resistant to chemical solvents (such as water), the electronic package structure formed by using the substrate according to the invention can be used in a high temperature, high pressure and humidity environment ( (Such as pressure cooker test) still has excellent reliability. [Explanation of the invention] The circuit substrate used in the present invention is generally reinforced with glass fiber β τ (^ ismalewide-triazine) resin, or FR-4 glass fiber reinforced ring = tree moon (Fiberglas s reinforced epoxy resin) core layer. The circuit substrate can generally be formed in the following steps

V. Description of the invention (4) $: ⑴Put a copper (_shanjiao) that has been roughly saccharified on the surface to the 'core layer'. (6 气层 [Formula in; copper layer on the core layer to form the desired conductive electricity :. The circuit board can be used for the present invention can contain any number of layers

I-side: The circuit board of t :: has formed a solder mask on the #wiring surface. ·: The formation steps of the durable layer are as follows: a solder resist (a solder resist) (such as a photoimageable solder resist or a dry film solder resist) is applied to the wiring surface on the substrate, which can generally be immersed (Dipping soil, method), spraying method (spray method), or screen printing); (b) a pre-curing step is performed at this time, the layer of solder resist 1 2 0 is based on 6 〇 ° C -1 0 〇 ° C to form a solder resist port (solder resist fi lm); (c) imaging and developing the solder resist to form the desired solder resist pattern One of them is to use a mask with a desired pattern to image a fixed area of the solder mask, and after development, the solder resist in the specific area will be: so that a part of the substrate is preset to be exposed to the freshness prevention. membrane.

According to the method for improving the adhesion between a plastic sealant and a circuit board having a solder resist layer according to the present invention, the surface of the circuit board having a solder resist layer is roughened by using a permanganate deslagging process. The high-rhenium salt degumming process includes three steps. In the first step, a swelling solution (such as di ethy 1 ene glycol monobutyl ether) is used

In order to soften the structure of the residual film, in the second step, a nanamate oxidant (such as sodium, bell, and lysine permanganate solution) is used to roughen the circuit

P00-161.ptd Page 7 V. Description of the Invention (5) f, on? The surface of the solder film; in the third step, a neutralizing solution (such as: m 'dilute sulfuric acid or hydrochloric acid) is used to neutralize and remove permanganate. —In general, the circuit substrate to be processed is immersed in a way that contacts each of the above solutions, and at each step, the ancient and the six feet are washed. Ping ,, and Tian § In the second step, the alkaline dimanganese hafnium; the salt bath is generally heated to "0 T or higher, and the residence time manganese: gg 2 is generally twenty minutes or more. In addition, the alkaline permanganese phosphonium salt bath may be replaced by an alkaline dichromate solution. In other preferred embodiments of the present invention, the step of forming a circuit substrate with a solder mask layer can be achieved by a plasma-removing process, a sandblasting process, or a brushing process. In the electro-water slag removal process, the circuit board and board system with a solder resist layer is placed between a pair of parallel electrical board plates, which are spaced apart from each other and extend over the entire surface of the substrate. The plasma slag removal process is generally gas. In the tank, the air in the # 2 is discharged and replaced with mixed air oxygen (f gas = Dunmethane or oxygen and tetrafluoromethane). Then, a pair of power radio frequency electric fields are applied to the pair of flat plates to generate electrocondensation between the flat plates. The plasma surrounding the substrate to be processed between the flat plates will generate a plurality of discharge galvanic isolation and roughen the surface of the solder mask on the circuit substrate. In the spraying process, pressurized water is commonly used as a propellant. In general, water type sand blasting allows faster and more efficient surface roughening than oxygen sand blasting. During the brush grinding process, the circuit board with a solder resist is coated with an abrasive.

Page 8 486791 V. Description of the invention (6) (abrasive) Jet blasting (scrub) surface treatment, then water washing and drying, In addition, it can also use a polishing wheel (ruo buff) for surface Process, then wash and dry. The table contains the use of slag removal process technology to provide-a kind of substrate roughening. 仫 Because the solder mask layer on the surface of the circuit substrate appears rough on the surface, so the interlock mechanism on the solder mask layer / sealing interface is right. , There is still a mechanical interlocking mechanism outside the bond, 'due to the mechanical

The wet inversion plant is formed at high temperature, high pressure, and high X using the substrate of the present invention: electron reliability. Therefore, the environment of ‘(such as the pressure cooker test) is not easy to achieve high temperature and high pressure and high reliability. Decreased due to the exfoliation of the sealant. Although the present invention has been described in the foregoing preferred embodiment, 'any person skilled in the art, in :: away:' is not intended to be used within the target range. Various changes and modifications can be made. The spirit and scope of the application are defined by the scope of the attached patent application as the protection scope of the present invention.

486791

POO-161.ptd Page 10

Claims (1)

486791 Case No. 8912823ft VI. Application for Patent Scope 1. A method for improving the adhesion of a plastic sealant and a circuit substrate with a solder resist layer. The substrate is used for packaging a semiconductor element, and the method includes using a high fidelity acid. The desmearing process is used to roughen the surface of the circuit board with a solder mask. The permanganate desmearing process includes sequential treatment with three different solutions. These solutions are sequentially a swelling solution and an alkaline permanganate. Salt solution and neutralization solution. 2. The method for improving the adhesion between the sealant plastic and the circuit with a solder resist layer according to item 1 of the scope of the patent application, wherein the swelling solution contains diethylene glycol butyl (diethy 1 eneg 1 yc ο 1 m ο η〇buty 1 ether). 3. The method for improving the adhesion between the sealant plastic and the circuit substrate having a solder resist layer according to item i of the patent application range, wherein the neutralization solution includes an inorganic acid solution. 1. A method and method for improving adhesion between a plastic sealant and a circuit substrate having a solder resist layer. The substrate is used to package a semiconductor device. The method includes a thickening process of chromate degumming to roughen the substrate. The circuit base of the anti-recording layer, wherein the dichromate degumming process includes three different solutions For two reasons, these / cereals are a swelling solution, an alkaline dichromate solution, and a neutralization solution in this order. 486791 Case No. 89128236 Amendment 6. The scope of the patent application uses a plasma deslagging process to roughen the surface of the circuit board with a solder mask. 6. An improved adhesion between the plastic sealant and the circuit board with a solder mask. In the method, the substrate is used for packaging a semiconductor element, and the method includes using a sand blasting process to roughen the surface of the circuit substrate with a solder resist layer. 7. A method for improving adhesion between a plastic sealant and a circuit substrate with a solder mask layer, the substrate is used to package a semiconductor element, the method includes roughening the circuit with a solder mask layer by using a brush grinding process Substrate surface. POO-161.ptc Page 12