设计了 nBn结构的 InAs/GaSb II类超晶格红外探测器, 从理论和实验两方面对 nBn器件的暗电流特性进行了研究, 研究结果表明: 理论计算的暗电流和实际测试结果趋势一致。另外, 研制了 p-i-n结构器件并与 nBn器件进行了比较, 测试结果显示: 在 77 K温度下, nBn器件的暗电流要比 p-i-n器件暗电流小 2个量级。温度升高到 150 K时, nBn器件暗电流变大 2个量级, 而 p-i-n器件暗电流变大 4个量级; nBn器件峰值探测率下降到 1/5, p-i-n器件峰值探测率下降 2个量级。可见 nBn器件适合高温工作, 适合高性能红外焦平面探测器的研制。

An infrared detector based on type-II InAs.GaSb strain layer superlattice with the nBn design has been designed. Dark current of the nBn device was studied through the theoretic calculation and the experiment. The results show that dark current of the theoretic calculation is consistent with the trend of the experimental results. In addition, the p-i-n device was developed, and compared with the nBn device. Test results present that dark current of the nBn device is two orders of magnitude lower than dark current of the p-i-n device at 77 K. When the temperature rises to 150 K, dark current of the nBn device increases by two orders of magnitude, and dark current of the p-i-n device increases by four orders of magnitude; the specific detectivity D. of the nBn device reduces to 1/5, and the D. of the p-i-n device decreases by over two orders of magnitude. Therefore nBn devices are suitable to work at high temperature, which will be fit to development of high performance infrared focal plane arrays.