The effect of compressive strain on the performance of p-type quantum-well infrared photodetectors

Infrared absorption of an In0.2Ga0.8As/GaAs quantum-well infrared photodetector employing a p–n–p camel diode structure

“…The dark current of a conventional p -i -p QWIP with a similar active area ͑50ϫ50 m 2 ͒ measured at 77 K is also shown for comparison. 10 Note that the dark current of the detector measured at the same temperature was reduced drastically by the introduction of the potential barrier induced by the n ϩ ␦-doped region. While the I -V characteristics of the conventional p -i -p QWIP showed a symmetrical behavior, those of the detector employing a p -n -p camel diode structure showed an asymmetrical behavior due to the potential barrier.…”

“…[5][6][7][8][9] A normal incident infrared absorption of QWIPs can also be achieved by the use of hole intersubband transitions, where the strong hole-band mixing of a multiple-quantum-well ͑MQW͒ might allow normal incident absorptions. 10,11 While the detectivity of infrared detectors is strongly dependent on the dark current, there have been few reports which address issues related to material structures for reducing the dark current. 12,13 In this letter, the normal incident infrared absorption of a MQW utilizing the hole intersubband transition and the reduction of the dark current by the use of a p -n -p camel diode structure are reported.…”