底镀层对陶瓷封装芯腔表面高温变色的影响

研究了Ni底镀层和不同Co含量的Ni-Co合金底镀层对陶瓷封装芯腔镀金层表面抗高温变色能力的影响。420℃、15 min的高温考核表明:w(Co)超过10%以上的Ni-Co合金底镀层,对陶瓷封装芯腔表面抗高温变色能力明显优于纯Ni底镀层。镀层中w(Co)超过10%以上时,抗高温变色能力并不会随着Co含量增加而提高,仅随底镀层厚度的增加而明显增强。因而在陶瓷封装中,采用厚度大于4 mm的、含Co 15%左右的Ni-Co合金,代替Ni作为底镀层是可行的。

The Effect of Co Content of Underlayers on the Resistance to Surface Discoloration of Cavities in Ceramic Packages in High Temperature Aging

Studied was the effect of Co content of the underlayer of Ni and Ni-Co alloy on the resistance to the surface discoloration of cavities in ceramic packages in high temperature aging. High-temperature test (heating at 420C for 15 minutes) result shows that it is possible to replace Ni with Ni-Co alloy as an underlayer when Co content is higher than 10 wt% in plating. The resistance to the surface discoloration of Ni-Co alloy underlayer at high-temperature almost not changes with the increase of Co content in the range from 10 wt% to 20 wt%. Resistance to surface discoloration of cavity in ceramic packages at high-temperature obviously increases with the increase of underlayer thickness. Ni-Co alloy of 4 mm in thickness and 15 wt% Co content is recommended to replace Ni as an underlayer in ceramic packages.