CN117926257A

CN117926257A - Copper etching solution without unrercut and phosphorus

Info

Publication number: CN117926257A
Application number: CN202311558876.3A
Authority: CN
Inventors: 陈敬伦; 陈芬; 张晴晴
Original assignee: Nantong Qun'an Electronic Materials Co ltd
Current assignee: Nantong Qun'an Electronic Materials Co ltd
Priority date: 2023-11-22
Filing date: 2023-11-22
Publication date: 2024-04-26

Abstract

The invention discloses a copper etching solution without unrercut and phosphorus, which comprises a solvent, hydrogen peroxide, sulfuric acid, a hydrogen peroxide stabilizer, a revetment agent, an etching rate stabilizer and a penetrating agent; the concentration of the hydrogen peroxide is 20-160g/L; the concentration of the sulfuric acid is 40-140g/L; the concentration of the hydrogen peroxide stabilizer is 0.1-10g/L; the concentration of the revetment agent is 0.1-10g/L; the concentration of the etching rate stabilizer is 0.1-20g/L; the concentration of the penetrating agent is 0.1-30g/L. The copper etching solution has the advantages of controllable speed, no unrercut, high precision, no phosphorus and the like, and can greatly improve the qualification rate of the final finished product and reduce the production cost.

Description

Copper etching solution without unrercut and phosphorus

Technical Field

The invention relates to the field of etching liquid, in particular to a copper etching liquid without unrecicut and phosphorus.

Background

Etching techniques include techniques for uniformly removing the entire surface of the material and for selectively partially removing the pattern. Etching techniques can be classified into wet etching (wet etching) and dry etching (dry etching). Wet etching is the most common and lowest equipment cost etching method. The wet etching is mainly performed by chemical reaction between the solution and the material to be etched, so that proper chemical solution can be prepared and selected to obtain the required etching rate (etching rate) and the good etching selectivity (selectivity) of the material to be etched, the photoresist and the underlying material.

However, as the circuit of the PCB industry is finer, the wet etching is isotropic (isotropic) due to the non-directionality of the chemical reaction, and at this time, when the etching solution is etched longitudinally, the lateral etching will occur simultaneously, thereby causing undercut (undercut) phenomenon, resulting in distortion of the line width of the pattern. Therefore, there is a need to develop a copper etching solution that has a controllable etching rate, is free of unrecict, has high accuracy, and does not contain phosphorus.

Disclosure of Invention

In order to solve the problems, the invention provides the copper etching solution without the unrefine and containing phosphorus, which has the advantages of controllable speed, unrefine and containing no phosphorus, and the like, and can greatly improve the qualification rate of the final finished product and reduce the production cost.

The technical scheme of the invention is as follows: a copper etching solution without unrercut and phosphorus comprises a solvent, hydrogen peroxide, sulfuric acid, a hydrogen peroxide stabilizer, a bank protection agent, an etching rate stabilizer and a penetrating agent;

The concentration of the hydrogen peroxide is 20-160g/L; the concentration of the sulfuric acid is 40-140g/L; the concentration of the hydrogen peroxide stabilizer is 0.1-10g/L; the concentration of the revetment agent is 0.1-10g/L; the concentration of the etching rate stabilizer is 0.1-20g/L; the concentration of the penetrating agent is 0.1-30g/L.

Further, the solvent is water.

Further, the concentration of the hydrogen peroxide is controlled to be 35%. According to the addition amount of the hydrogen peroxide, the etching speed is controlled, the hydrogen peroxide can be controlled to be 20-160g/L, but controlled to be 30-80g/L, the optimum protection of the unrecict is achieved, and the etching speed is stable.

Further, the concentration of sulfuric acid is controlled to be 40-70g/L, and the protection effect of the unrercut is optimal.

Further, the hydrogen peroxide stabilizer is used for reducing the cracking of hydrogen peroxide. The hydrogen peroxide stabilizer comprises one or more of p-phenylurea, urea or other amide substances and one or more of p-hydroxybenzenesulfonic acid or other benzenesulfonic acid substances.

Further, the revetment agent is more likely to chelate Cu at the line corners, sidewalls, and thereby infinitely reduce the generation of unrecict. The revetment agent comprises one or more of 5-aminotetrazole, benzotriazole, methylbenzotriazole or other azole substances.

Further, the etching rate stabilizer serves to stabilize the effect of the biting amount of copper with an increase in copper ions. The etching rate stabilizer comprises one or more of ethylene glycol, propylene glycol, butanediol, ethylene glycol butyl ether or other alcohol ethers.

Furthermore, the penetrating agent reduces the surface tension of the copper surface, can enable etching liquid to penetrate or accelerate to penetrate into the copper surface, increases the copper biting amount of base material copper, and is beneficial to bottom copper cleaning. One or more of the penetrating agent polyquaternary ammonium salt, phenylurea, benzyl alcohol, phenethyl alcohol, phenetole and phenoxyethanol.

The beneficial effects of the invention are as follows: the etching solution disclosed by the invention has the advantages of controllable etching speed, good stability, no unrercut, high precision and the like, can greatly improve the qualification rate of a final finished product, does not contain phosphorus, and is environment-friendly.

Drawings

The invention is further described below with reference to the drawings and examples.

Fig. 1 is a microscopic photograph of example 1.

Fig. 2 is a microscopic photograph of example 2.

Fig. 3 is a microscopic photograph of the comparative example.

Detailed Description

The technical scheme of the present invention will be clearly and completely described in the following detailed description.

The invention discloses a copper etching solution without un-rcut and phosphorus, which comprises a solvent, hydrogen peroxide, sulfuric acid, a hydrogen peroxide stabilizer, a bank protection agent, an etching rate stabilizer and a penetrating agent. Other additives may be added.

Example 1

The copper etching solution without un-rcut and phosphorus in the embodiment comprises 50g/L of hydrogen peroxide (35%), 60g/L of sulfuric acid, 1g/L of p-hydroxy benzene sulfonic acid, 0.5g/L of 5-aminotetrazole, 3g/L of glycol, 1g/L of phenetole and the balance of water.

Example 2

The copper etching solution without un-rcut and phosphorus in the embodiment comprises 40g/L of hydrogen peroxide (35%), 70g/L of sulfuric acid, 1g/L of 4-hydroxy benzenesulfonic acid, 1g/L of benzotriazole, 3g/L of butanediol, 1g/L of phenethyl alcohol and the balance of water.

Comparative example

The copper etching solution in the embodiment comprises 80g/L of hydrogen peroxide (35%), 120g/L of sulfuric acid, 1g/L of p-hydroxybenzenesulfonic acid, 3g/L of glycol, 1g/L of phenethyl alcohol and the balance of water.

Table 1 shows the controls of the examples and comparative examples

Formulation of	Copper amount of copper	Microscopic photograph	Conclusion(s)
				Example 1	4um	As in figure 1	Unrendercut-free
Example 2	4um	As in figure 2	Unrendercut-free
				Comparative example	4um	As shown in FIG. 3	With a single side of unrecict of about 3.25um

As can be seen from Table 1, the copper etching solution of the invention has the advantages of no unrercut, high precision and the like, can greatly improve the qualification rate of the final finished product, does not contain phosphorus, and is environment-friendly.

The foregoing description of the preferred embodiments of the present invention is not intended to limit the invention, and those skilled in the art may make various modifications and equivalents within the spirit and scope of the invention, and such modifications and equivalents should also be considered as falling within the scope of the technical solution of the present invention.

Claims

1. A copper etching solution without undercut and phosphorus, characterized by comprising a solvent, hydrogen peroxide, sulfuric acid, a hydrogen peroxide stabilizer, a revetment agent, an etching rate stabilizer and a penetrant;

The concentration of the hydrogen peroxide is 20-160 g/L; the concentration of the sulfuric acid is 40-140 g/L; the concentration of the hydrogen peroxide stabilizer is 0.1-10 g/L; the concentration of the shore protection agent is 0.1-10 g/L; the concentration of the etching rate stabilizer is 0.1-20 g/L; and the concentration of the penetrant is 0.1-30 g/L.

2. The undercut-free and phosphorus-free copper etching solution according to claim 1, wherein the solvent is water.

3. The undercut-free and phosphorus-free copper etching solution according to claim 1, wherein the concentration of the hydrogen peroxide is controlled at 30-80 g/L.

4. The undercut-free and phosphorus-free copper etching solution according to claim 1, wherein the concentration of sulfuric acid is controlled at 40-70 g/L.

5. The undercut-free and phosphorus-free copper etching solution according to claim 1, characterized in that the hydrogen peroxide stabilizer comprises one or more of p-phenylurea, urea or other amide substances and one or more of p-hydroxybenzenesulfonic acid or other benzenesulfonic acid substances.

6. The undercut-free and phosphorus-free copper etching solution according to claim 1, wherein the bank protection agent comprises one or more of 5-aminotetrazolyl, benzotriazole, methylbenzotriazole or other azole substances.

7. The undercut-free and phosphorus-free copper etching solution according to claim 1, characterized in that the etching rate stabilizer comprises one or more of ethylene glycol, propylene glycol, butylene glycol, ethylene glycol butyl ether or other alcohol ethers.

8. The undercut-free and phosphorus-free copper etching solution according to claim 1, characterized in that the penetrant is one or more of polyquaternary ammonium salts, phenyl urea, benzyl alcohol, phenylethyl alcohol, phenethyl ether, and phenoxyethanol.