小间距碲镉汞红外探测器孔内电极制备研究  

Study on preparation of in-hole electrodes for small-pitch mercury cadmium telluride infrared detectors

作　　者：邢志韬 孙玉杰 宁提 何斌 牛佳佳 王成刚 XING Zhi-tao;SUN Yu-jie;NING Ti;HE Bin;NIU Jia-jia;WANG Cheng-gang(CETC Electro-Optics Technology Co.Ltd.,Beijing 100015,China)

机构地区：[1]中电科光电科技有限公司,北京100015

出　　处：《激光与红外》2025年第4期569-574,共6页Laser & Infrared

摘　　要：缩小像元间距是提升红外探测器性能的重要方向之一,像元尺寸的减小在红外探测器提高分辨率、降低制造成本、减小发热量、降低功耗等方面有着重要作用。电极作为连接碲镉汞芯片与外部读出电路的桥梁,决定了器件的性能与可靠性。但是在小间距红外探测器的电极制备过程中经常出现剥离困难、电极覆盖情况差等现象,本文分析离子束沉积中角度、温度等条件对电极生长的影响,结果表明升高沉积温度使沉积的金属膜层与HgCdTe附着力变得更好,沉积温度越高,侧壁覆盖越好。沉积角度越接近45°,侧壁越薄,较薄的侧壁电极可以使得剥离工艺难度更低,降低孔内电极侧壁脱落的几率接触。同时沉积角度也是控制生长薄膜的粗糙度的重要参数,改变沉积角度可以得到粗糙度更低的金属膜层。在沉积温度为T0+40℃,沉积角度为45°的条件下,成功制备了易于剥离、粗糙度低、附着力好的孔内电极结构,提高了碲镉汞红外器件性能。Reducing the pixel pitch is a crucial approach to enhancing the performance of infrared detectors,and the reduction of pixel size plays an important role in infrared detectors to improve the resolution,reduce the cost of manu-facturing and the heat generation,and lower the power consumption.However,the electrode,which serves as a vital link between the HgCdTe chip and the external readout circuit,poses challenges during preparation for small-pitch in-frared detectors,often leading to stripping difficulties and inadequate electrode coverage.In this paper,the effects of angle,temperature and other conditions on the growth of the electrode are analyzed,and the results show that elevating the deposition temperature makes the deposited metal film layer with HgCdTe adhesion become better,and higher the deposition temperature,the better the sidewall coverage.The closer the deposition angle is to 45°,the thinner the side-wall is,and the thinner sidewall electrode can make the stripping process less difficult,and reduce the chance of con-tact with the electrode sidewall falling off in the hole.At the same time,the deposition angle is also an important pa-rameter to control the roughness of the grown film,and changing the deposition angle yields a metal film layer with lower roughness.Under the condition of deposition temperature of T0+40℃ and deposition angle of 45°,the in-hole electrode structure with easy peeling,low roughness and good adhesion is successfully prepared,which improves the performance of HgCdTe infrared devices.

关 键 词：碲镉汞离子束 沉积薄膜技术 孔内沉积 电极剥离 

分 类 号：TN219[电子电信—物理电子学] TN205