混合电路引壳引线局部镀金技术研究

混合电路引壳引线多、体积大，用整体镀金技术导致成本加大，而封装时只需引线镀金。采用外壳整体镀镍后引线部分镀金工艺可实现这一要求。但镍层的电极电位必须与金的电极电位相近，防止金被镍置换。研究给出了镀镍的方法和镀金液的配方，效果十分良好。

Study of Selective Gold Plating Technique on Leads of the Hybrid Integreted Circuit

The integral gold plating on the hybrid integrated circuit (HIC) package that has more leads and bigger volume will lead production cost to increase. In fact, gold only plated on the leads of HIC can meet the performance requirements. Selective gold plating after the general nickel plating in the whole package can realize this purpose. But the electrode potential of the nickel coating must be similar to that of gold, to prevent gold to be replaced out by nickel in the gold plating bath. An effective method of nickel plating and a satisfied formulation of gold plating both are given in this paper.