Application of triamine base substituted phenol or triamine base substituted thiophenol and micro-etching treating fluid

Abstract

The invention relates to micro-etching treating fluid. The micro-etching treating fluid comprises 30.0-60.0 g / L of sulfuric acid, 10.0-20.0 g / L of hydrogen peroxide, 0.1-1.0 g / L of hydrogen peroxide stabilizer, 2.0-5.0 g / L of inhibitor and 1 L of added water. The inhibitor is selected from the triamine base substituted phenol or the triamine base substituted thiophenol. The above micro-etching treating fluid is used for printed circuit board OSP pretreatment, a clean and rough copper surface can be formed, a protection film can be formed in combination with a copper face in the micro-etching process, the copper face electron supplying speed during the copper-gold electrochemical reaction is reduced, accordingly the potential difference between the copper and the gold is reduced, the biting corrosion rate of a copper welding pad is reduced, generation of the galvanic effect is restrained to the maximum degree, the phenomena of the color difference, area reduction or line excessive corrosion or even biting off cannot happen to the copper face connected with the gold face and obtained after micro-etching treatment, and meanwhile the phenomenon of coloring after OSP treatment can be effectively prevented from happening to the copper surface.

Description

technical field [0001] The invention relates to the technical field of printed circuit board chemicals, in particular to the application of triamine-substituted phenol or triamine-substituted thiophenol and a microetching treatment solution. Background technique [0002] During the rapid development of printed circuit boards, due to the high popularity of consumer electronic products such as smart phones and tablet computers, the traditional use of copper wires as signal transmission has been unable to adapt to the high-frequency and high-speed applications of the above-mentioned consumer electronic products. , a copper / gold hybrid printed circuit board is proposed and applied to the above-mentioned consumer electronic products. In the design of copper / gold mixed printed circuit boards, there are often gold-copper (Au-Cu) solder connections, especially when the gold / copper area ratio exceeds 200:1, when the organic solderable protective film (OSP) After treatment, on the co...

AI Technical Summary

Problems solved by technology

[0006] It can be seen from the above reaction formula that if there is a potential difference between gold and copper, the Giavani effect will occur in the microetching solution. Copper loses electrons to form an anode, gold gains electrons to become a cathode, and gold-copper forms a primary battery, making the circuit The corrosion rate of the copper surface connected to the gold surface on the board is accelerated. As a result, the area of ​​the copper pad becomes smaller, or the hole copper becomes thinner and opens, which seriously affects the quality of the PCB and reduces the qualified rate of finished products.

[0007] In addition, during the production process of PCB boards, the crystallization of the copper surface is required to be more and more dense, and when such dense copper crystals are subjected to micro-etching treatment, the ordinary micro-etching treatment solution cannot perform "intergranular corrosion" on the dense crystals. Inhomogeneous erosion occurs, and the copper surface cannot form a rough shape, resulting in insufficient thickness of the anti-oxidation protective film formed during the subsequent OSP treatment, and poor adhesion, causing the copper surface to appear "colored", which affects the subsequent PCB board assembly. The solderability and reliability of the device, the current industry acceptance standard is that the thickness of the OSP anti-oxidation protective film is 0.3 ~ 0.5 μm

Images