GaAs/AlGaAs quantum-well infrared photodetectors on GaAs-on-Si substrates

Abstract

In this letter, we describe the characteristics of molecular beam epitaxy GaAs/AlGaAs quantum-well infrared photodetectors (QWIP’s) grown on a GaAs substrate, and on a GaAs-on-Si substrate produced by metalorganic chemical-vapor deposition. Important issues for QWIP applications such as dark current, spectral response, and absolute responsivity are studied. We find that compared to a similar detector structure grown on a GaAs substrate, the detector grown on a GaAs-on-Si substrate exhibits similar dark current and absolute responsivity while displaying a small blueshift in the spectral response.

Advanced monolithic quantum well infrared photodetector focal plane array integrated with silicon readout integrated circuit

“…This detectivity is one order of magnitude lower than that of the QWIP-on-InP, which is 3.3 · 10 10 cm Hz 1=2 /W. The detectivity of our QWIP-on-Si detector is about one order of magnitude higher than that of a GaAs/AlGaAs QWIP-on-Si detector [25].…”