Yu Jing, Fu Yuegang, Lu Lidan, Chen Weiqiang, Ou Jianzhen, Zhu Lianqing
The School of Electro-Optical Engineering, Changchun University of Science and Technology, Changchun 130022, China.
School of Instrument Science and Opto-Electronics Engineering, Beijing Information Science and Technology University, Beijing 100192, China.
Micromachines (Basel). 2025 May 14;16(5):575. doi: 10.3390/mi16050575.
Extended shortwave infrared (eSWIR) detectors operating at high temperatures are widely utilized in planetary science. A high-performance eSWIR based on pBin InAs/GaSb/AlSb type-II superlattice (T2SL) grown on a GaSb substrate is demonstrated. It achieves the optimization of the device's optoelectronic performance by adjusting the p-type doping concentration in the AlAsSb/GaSb barrier. Experimental and TCAD simulation results demonstrate that both the device's dark current and responsivity grow as the doping concentration rises. Here, the bulk dark current density and bulk differential resistance area are extracted to calculate the bulk detectivity for evaluating the photoelectric performance of the device. When the barrier concentration is 5 × 10 cm, the bulk detectivity is 2.1 × 10 cm·Hz/W, which is 256% higher than the concentration of 1.5 × 10 cm. Moreover, at 300 K (-10 mV), the 100% cutoff wavelength of the device is 1.9 μm, the dark current density is 9.48 × 10 A/cm, and the peak specific detectivity is 7.59 × 10 cm·Hz/W (at 1.6 μm). An eSWIR focal plane array (FPA) detector with a 320 × 256 array scale was fabricated for this purpose. It demonstrates a remarkably low blind pixel rate of 0.02% and exhibits an excellent imaging quality at room temperature, indicating its vast potential for applications in infrared imaging.
工作在高温下的扩展短波红外（eSWIR）探测器在行星科学中得到了广泛应用。展示了一种基于在GaSb衬底上生长的pBin InAs/GaSb/AlSb II型超晶格（T2SL）的高性能eSWIR。通过调整AlAsSb/GaSb势垒中的p型掺杂浓度实现了器件光电性能的优化。实验和TCAD模拟结果表明，随着掺杂浓度的增加，器件的暗电流和响应率均增大。这里，提取体暗电流密度和体微分电阻面积来计算体探测率，以评估器件的光电性能。当势垒浓度为5×10¹⁸ cm⁻³时，体探测率为2.1×10¹¹ cm·Hz¹/²/W，比1.5×10¹⁸ cm⁻³的浓度高256%。此外，在300 K（-10 mV）时，器件的100%截止波长为1.9 μm，暗电流密度为9.48×10⁻⁷ A/cm²，峰值比探测率为7.59×10¹¹ cm·Hz¹/²/W（在1.6 μm处）。为此制作了一个阵列规模为320×256的eSWIR焦平面阵列（FPA）探测器。它展示出极低的0.02%的盲像素率，并且在室温下表现出优异的成像质量，表明其在红外成像应用中具有巨大潜力。
