摘要由于高等科学技术及设备的迅猛发展、电子设备的构造变得愈加精细化,零件越来越精密,也越来越多样。PCB,即集成电路和其他电子组件的薄板,上面的线路越来越精密,工业上对于它的表面处理同时也有着向无铅化方向发展的重要趋势。其中,OSP(Organic Solderability Preservatives)的发展是公认地十分重要的一个研究热点。OSP是一种由有机唑类物质、低分子有机酸、水和助成膜剂组成的混合溶液,中文名字是有机保焊膜,也有外文文献称之为Preflux。特定的试验环境之下,OSP能够和二价铜离子在铜表面发生络合反应,形成一种光滑平整的络合物薄膜。它能够阻碍PCB铜表面和空气中的氧气接触,从而能富有成效地防止铜与氧气发生氧化反应导致被腐蚀,而在焊接工艺中,也很容易通过一些方法被除去,不影响焊接的进行。
通过学习铜的抗氧化原理,讨论有机保焊剂与铜离子发生络合反应,形成络合膜的基本原理和实验条件,深入探讨0SP的具体组成成分,对每一个成分的加入量和所占质量分数合理分析,研制出在抗氧化时间长同时在焊接时能经受高温的OSP配方,并研究在将它用于PCB铜表面抗氧化处理时,能够设定的最佳工艺条件。最后,对经过抗氧化处理而形成的抗氧化膜的抗高温进行测试等。48038
关键词: 印制线路板; 铜; 抗氧化剂; 苯并咪唑衍生物
毕业论文设计说明书外文摘要
Title Design and preparation of antioxidant film in the surface of the conductive line.
Abstract
With the rapid development of electronic technology and emerges of more complex electronic devices, more and more sorts of parts are needed, the line and parts, which are on top of sheet (PCB) of integrated circuits and other electronic components, are becoming increasingly intensive, and there is a rapidly growing trend for technology of PCB surface treatment towards the replacement of tin-lead, which accelerated the development of OSP (Organic Solderability Preservatives), also called Preflux in English. OSP is mixed solution composed by an organic acid from the Benzimidazole Derivatives, low molecular weight, water and additive composition. Provided with certain conditions, OSP can react with cupric ions on the surface of copper, resulting in the production of a dense film that not only can act as a barrier layer between the copper surface of the PCB and the air, effectively preventing copper from being oxidized and corroded, but also can be removed before welding, which can help the surface of copper maintain good solderability.
Based on the principle of anti-oxidation on the surface of PCB copper and reaction between OSP and copper, I discussed the main components of 0SP, then developed its formula featuring long antioxidant time and studied the best optimum conditions of using this formula. Finally, I tested oxidation resistant ability of PCB after being treated with OSP.
Keywords PCB, Organic Solderability Preservatives, Benzimidazole Derivatives.
目 次
1 引言(或绪论) 1
1. 1 国内外研究进展 1
1.2 课题的研究目标及主要内容 2
2 PCB铜表面抗氧化剂配方的设计 4
2.1 在Cu表面使用OSP络合生成抗氧化薄膜的原理 4
2.2 抗氧化剂的基本组成 4
2.3基于苯并咪唑的抗氧剂 5
3.基于苯并咪唑OSP的抗氧化处理方法