InAs/InGaAs/InAlAs interband quantum well infrared photodetector (IQWIP) with cut-off response wavelength at 1.93 μm

Abstract

Utilizing the high efficiency of the localized carrier extraction in the low-dimensional semiconductors within a PN junction, an InP-based InAs/InGaAs/InAlAs interband quantum well infrared photodetector has been investigated. Although the thermal energy is much less than the band offset, the detector still realizes photo response up to 1.93 μ m. In addition, the detector shows the room-temperature external quantum efficiency of 7% and detectivity of 1.81 ×1010 cm /W without anti-reflection layer. Based on the above quantum efficiency value, an absorption coefficient of 1.1 ×104 cm-1 was also determined. It is clear that our work provides compelling evidences for the possibility of novel and low-cost infrared photodetector.