(西北工业大学 凝固技术国家重点实验室，西安 710072)
摘 要: 为实现高电阻CdZnTe半导体(简称CZT)接触电极与外引线的超声波焊接，采用正交实验法探讨CZT接触电极与引线超声波焊接质量的影响因素及其作用规律。结果表明：经机械抛光表面处理的CZT晶片，采用离子溅射法制备的金电极与外引线间具有较高的超声波焊合率，能获得最佳焊点质量的电极厚度为180 nm。此外，CZT接触电极制备工艺和楔入压力都是影响CZT接触电极与引线超声波焊接质量的主要因素，当CZT接触电极制备工艺确定后，楔入压力成为影响CZT接触电极与引线超声波焊接质量的主要因素，焊接功率则为次要因素。经优化后CZT接触电极与引线超声波焊接主要工艺参数为：一焊楔入压力0.882 N；二焊楔入压力0.588 N；焊接功率1.5 W；焊接时间20 ms。
关键字: CdZnTe晶片；接触电极；超声波焊接；微观组织；正交实验法
CdZnTe wafer and down-lead wire
（State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi’an 710072, China）
Abstract: In order to make high resistance CdZnTe(CZT) room temperature X-ray or γ-ray detectors, the ultrasonic wire bonding technology between the CZT contact electrode and the down-lead wire was studied. The influence of the CZT contact electrode preparation technology and ultrasonic wire bonding parameters between the Au contact layer and the down-lead wire on the bonding quality was explored by orthogonal test. The results show that the ultrasonic wire bonding between the CZT contact electrode and the down-lead wire is easier to realize when the CZT wafers are mechanically polished and their contact electrodes are prepared by ion sputter technology. The optimum thickness of CZT contact electrode is 180 nm for the ultrasonic wire bonding. Furthermore, the bonding pressure and welding power have a great effect on the ultrasonic wire bonding rates between the down-lead wire and the CZT contact electrode after the electrode layer preparation technology of CZT wafer is fixed on. The optimized ultrasonic wire bonding parameters for the CZT contact electrode and the down-lead wire are the bonding power 1.5 W, the first bonding pressure 0.882 N, the second bonding pressure 0.588 N and the welding time 20 ms.
Key words: CdZnTe wafer; contact electrode; ultrasonic wire bonding; microstructure; orthogonal test
