(西北工業(yè)大學(xué) 凝固技術(shù)國(guó)家重點(diǎn)實(shí)驗(yàn)室,西安 710072)
摘 要: 為實(shí)現(xiàn)高電阻CdZnTe半導(dǎo)體(簡(jiǎn)稱CZT)接觸電極與外引線的超聲波焊接,采用正交實(shí)驗(yàn)法探討CZT接觸電極與引線超聲波焊接質(zhì)量的影響因素及其作用規(guī)律。結(jié)果表明:經(jīng)機(jī)械拋光表面處理的CZT晶片,采用離子濺射法制備的金電極與外引線間具有較高的超聲波焊合率,能獲得最佳焊點(diǎn)質(zhì)量的電極厚度為180 nm。此外,CZT接觸電極制備工藝和楔入壓力都是影響CZT接觸電極與引線超聲波焊接質(zhì)量的主要因素,當(dāng)CZT接觸電極制備工藝確定后,楔入壓力成為影響CZT接觸電極與引線超聲波焊接質(zhì)量的主要因素,焊接功率則為次要因素。經(jīng)優(yōu)化后CZT接觸電極與引線超聲波焊接主要工藝參數(shù)為:一焊楔入壓力0.882 N;二焊楔入壓力0.588 N;焊接功率1.5 W;焊接時(shí)間20 ms。
關(guān)鍵字: CdZnTe晶片;接觸電極;超聲波焊接;微觀組織;正交實(shí)驗(yàn)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


