Purpose

The purpose of this paper is to study an electrolytic etching method to prepare fine lines on printed circuit board (PCB). And the influence of organics on the side corrosion protection of PCB fine lines during electrolytic etching is studied in detail.

Design/methodology/approach

In this paper, the etching factor of PCB fine lines produced by new method and the traditional method was analyzed by the metallographic microscope. In addition, field emission scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) were used to study the inhibition of undercut of the four organometallic corrosion inhibitors with 2,5-dimercapto-1,3,4-thiadiazole, benzotriazole, l-phenylalanine and l-tryptophan in the electrolytic etching process.

Findings

The SEM results show that corrosion inhibitors can greatly inhibit undercut of PCB fine lines during electrolytic etching process. XPS results indicate that N and S atoms on corrosion inhibitors can form covalent bonds with copper during electrolytic etching process, which can be adsorbed on sidewall of PCB fine lines to form a dense protective film, thereby inhibiting undercut of PCB fine lines. Quantum chemical calculations show that four corrosion inhibitor molecules tend to be parallel to copper surface and adsorb on copper surface in an optimal form. COMSOL Multiphysics simulation revealed that there is a significant difference in the amount of corrosion inhibitor adsorbed on sidewall of the fine line and the etching area.

Originality/value

As a clean production technology, electrolytic etching method has a good development indicator for the production of high-quality fine lines in PCB industry in the future. And it is of great significance in saving resources and reducing environmental pollution.

中文翻译：

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电解蚀刻制备印制电路板细线及底切抑制研究

目的

本文的目的是研究一种在印刷电路板（PCB）上制备细线的电解蚀刻方法。并详细研究了电解蚀刻过程中有机物对PCB细线侧腐蚀防护的影响。

设计/方法/途径

本文通过金相显微镜分析了新方法和传统方法生产的PCB细线的蚀刻因素。此外，利用场发射扫描电子显微镜（SEM）和X射线光电子能谱（XPS）研究了2,5-二巯基-1,3,4-噻二唑、苯并三唑等四种有机金属缓蚀剂对底切的抑制作用，l-苯丙氨酸和l-色氨酸在电解蚀刻过程中。

发现

SEM结果表明，缓蚀剂可以极大地抑制电解蚀刻过程中PCB细线的底切。XPS结果表明，缓蚀剂上的N和S原子在电解蚀刻过程中与铜形成共价键，吸附在PCB细线侧壁形成致密的保护膜，从而抑制PCB细线底切。量子化学计算表明，四种缓蚀剂分子倾向于平行于铜表面，并以最佳形式吸附在铜表面。COMSOL Multiphysics 仿真表明，细线侧壁和蚀刻区域的缓蚀剂吸附量存在显着差异。

原创性/价值

电解蚀刻法作为一种清洁生产技术，对于未来PCB行业高品质细线的生产具有良好的发展指标。对节约资源、减少环境污染具有重要意义。