基于InAs/GaSb二类超晶格的中/长波双色红外探测器

Performance of Dual-Color Mid-/Long-Wavelength Infrared Detectors Based on Type-Ⅱ InAs/GaSb Superlattice

InAs/GaSb二类超晶格是一种通过在纳米尺寸上交替生长周期性异质结而构造的人工体材料,其有效带隙可以覆盖40~400meV。该量子体系材料不仅具有良好的均匀性,还拥有出色的光学特性,其电子有效质量高、光吸收系数大、量子效率高,已经成为第三代红外焦平面探测器的热门材料。本文利用分子束外延技术生长了背靠背势垒型中/长波双色红外探测器材料,通过标准工艺和阳极硫化技术,成功制备双波段NMπP-PπMN型红外探测器。在77K,中波峰值量子效率为32%,长波峰值量子效率为27%,50%截止波长分别为4.7μm和7.9μm。中波信号在+2V偏压下饱和,暗电流密度为0.06A/cm^2,长波信号在-1.4V偏压下饱和,暗电流密度为8.7A/cm^2。

InAs/GaSb type-Ⅱ superlattiee is an artificial material with alternating growth periodic heterojunction at nanometer size, and the effective band gap can cover from 40 meV to 400 meV. It has been regarded as a promising material system for third generation infrared detectors on account of its high uniformity and superior optical property, such as large electron effective mass, large absorption coefficient and high quantum efficiency. In this work, back-to-back dual-color mid-/long-wavelength infrared detec- tor material are grown by the molecular beam epitaxy （ MBE ） technology. The dual-band NMπP-PπMN infrard detector is successfully prepared by standard process and anode sulfuration technology. At 77 K, two channels present peak quantum efficiencies of 32% and 27% with respective 50% cutoff wavelengths of 4.7 pore and 7.9 μm. The mid-channel saturates at ＋ 2 V and the dark CUlTent density is 0.06 A/cm^2, while the long-channel saturates at -1.4 V and the dark current density is 8.7 A/cm^2.