钨螺旋线表面镀金薄膜热可靠性研究

Study on thermal reliability of Gold Filmon the surface of Tungsten Helix

摘要:

钨螺旋线是行波管的关键部件,随着行波管功率量级和工作频率的不断提高,其高频损耗和散热问题更加突出。为了解决这些问题,前期研究了钨螺旋线表面镀覆金膜的方法。由于螺旋线的工作温度较高,镀金薄膜的热可靠性如何？因此本文采用纳米划痕技术测试镀金薄膜和基体之间结合力大小,对预镀铜5s,10s,15s和20s,镀金均为1.5h后的试样高温(500℃,100h)处理前后的膜-基结合力进行了对比分析。结果表明：预镀铜5s,15s和20s的试样经高温处理后的膜-基结合力大小与常温下相比没有明显降低；预镀铜10s时的试样经高温处理后的膜-基结合力与常温下相比有所增大。钨螺旋线表面镀金薄膜热可靠性好。

Abstract:

Tungsten helix is a component of transfer wave tube (TWT), its high frequency loss and heat dissipation become serious with power level and working frequency of TWT increasing. To solve the problems, gold thin films were deposited on the surface of helix in our previous. How is the thermal reliability of gold thin films when helix operates at higher temperature? In this paper, the binding force between gold film and substrate was tested by using nanoscratch. The film binding forces of samples pre-plated copper respectively for 5s,10s,15s,20s and then gold-plated for 1.5h before and after heat treatment were analyzed.The results indicate that the films adhesion of samples after heat treatment show no obvious decrease compared with those of as-deposited samples. Especially, the binding force of the sample pre-plated copper for 10s after heat increases . The thermal reliability of gold films is good.