中长双色红外焦平面探测器组件技术研究

Study of MW/LW dual-band IRFPAs detector assemblies

在(211)B碲锌镉衬底上,采用分子束外延生长制备了PPP型中长双色碲镉汞材料,通过台面孔刻蚀、侧壁钝化等工艺,实现中长双色640×512红外焦平面探测器组件研制。中长双色碲镉汞材料测试结果表明,表面宏观缺陷(2~10μm)密度统计分布约773 cm^(-2),同时对材料进行了XRD双晶衍射半峰宽(FWHM)测试和位错腐蚀坑(EPD)统计,XRD测试FWHM约31.9 arcsec,EPD统计值约为5×10^(5) cm^(-2);双色器件芯片台面刻蚀深度达到8μm以上,深宽比达到1∶1以上,侧壁覆盖率达到72.5%。中长双色红外焦平面组件测试结果表明,中波波长响应范围为3.6~5.0μm,长波波长响应范围为7.4~9.7μm,中波向长波的串音为0.9%,长波向中波的串音为3.1%,中波平均峰值探测率达到3.31×10^(11) cm·Hz^(1/2)/W,NETD为17.7 mK;长波平均峰值探测率达到6.52×10^(10) cm·Hz^(1/2)/W,NETD为32.8mK;中波有效像元率达到99.46%,长波有效像元率达到98.19%,初步实现中长双色红外焦平面组件研制。

Based on(211) B CdZnTe substrate,PPP type medium-wave and long-wave dual-band HgCdTe material was prepared by molecular beam epitaxy.The medium-wave and long-wave dual-band 640×512 infrared focal plane detector assembly was fabricated by mesa-hole etching,sidewall passivation and other processes.The test results of MW/LW dual-band HgCdTe material show that the macro defects(2~10 μm) density is about 773 cm^(-2).Then,the materials were tested by XRD double crystal diffraction half peak width(FWHM) and etch pit density(EPD).The FWHM measured by XRD is about 31.9 arcsec,and the EPD is about 5 ×10^(5) cm^(-2).The etching depth of dual-band device chip mesa reaches 8 μm or more,the depth-width ratio is more than 1∶1,and the sidewall coverage is 72.5%.The test results of dual-band IRFPAs show that the response range is 3.6~5.0 μm and 7.4~9.7 μm.The crosstalk of medium wave to long wave is 0.9%,and long wave to medium wave is 3.1%.The average peak detection rate of medium wave and long wave reaches 3.31 × 10^(11) cm · Hz^(1/2)/w and 6.52 × 10^(10) cm · Hz^(1/2)/w,while the NETD and effective pixel rate are 17.7mK,32.8 mK and 99.46%,98.19%,respectively.