长/长波双色二类超晶格红外探测器研究

Research on InAs/GaSb type-II superlattice dual-band long-/long-wavelength infrared photodetector

报道了长/长波双色二类超晶格红外焦平面探测器组件的研制。通过能带结构设计和分子束外延技术,获得了表面质量良好的长/长波双色超晶格外延材料。突破了长波超晶格低暗电流钝化、低损伤干法刻蚀等关键技术,制备出像元中心距30μm的320×256长/长波双色InAs/GaSb超晶格焦平面探测器芯片。将芯片与双色读出电路互连,采用杜瓦封装,与制冷机耦合形成探测器组件。组件双波段50%后截止波长分别为7.7μm(波段1)和10.0μm(波段2)。波段1平均峰值探测率达到8.21×10^(10)cm·W^(-1)·Hz^(1/2),NETD实现28.8 mK;波段2平均峰值探测率达到6.15×10^(10)cm·W^(-1)·Hz^(1/2),NETD为37.8 mK,获得了清晰的成像效果,实现长/长波双色探测。

The development of type II superlattice dual-band long-/long-wavelength infrared focal plane photodetector is reported.Through the design of energy band structure and molecular beam epitaxial technology,dual-band long-/long-wavelength superlattice epitaxial material with good surface quality has been obtained.The 320×256 dual-band long-/long-wavelength InAs/GaSb superlattice focal plane photodetector with pixel center distance of 30μm was prepared by breaking through the key technologies of low dark current passivation and low damage dry etching.The detector chip is interconnected with a dual color readout circuit,packaged in a Dewar package,and coupled to a refrigerator to form a detector assembly.The dual-band 50%cut-off wavelengths of the photodetector are 7.7μm(band 1)and 10.0μm(band 2),respectively.The average peak detectivity of band 1 reached 8.21×10^(10)cm·W^(-1)·Hz^(1/2),and NETD achieved 28.8 mK.The average peak detectivity of band 2 reached 6.15×10^(10)cm·W^(-1)·Hz^(1/2),and the NETD was 37.8 mK.Clear imaging of both colors has been achieved,demonstrating the realization of long-/long-wavelength dual-band photodetection.