High-responsivity high-gain In/sub 0.53/Ga/sub 0.47/As-InP quantum-well infrared photodetectors grown using metal-organic vapor phase epitaxy

Abstract

We report the growth and fabrication of bound-to-bound In/sub 0.53/Ga/sub 0.47/As-InP quantum-well infrared photodetectors using metal-organic vapor phase epitaxy. These detectors have a peak detection wavelength of 8.5 /spl mu/m. The peak responsivities are extremely large with R/sub pk/=6.9 A/W at bias voltage V/sub b/=3.4 V and temperature T=10 K. These large responsivities arise from large detector gain that was found to be g/sub n/=82 at V/sub b/=3.8 V from dark current noise measurements at T=77 K and g/sub p/=18.4 at V/sub b/=3.4 V from photoresponse data at T=10 K. The background-limited temperature with F/1.2 optics is T/sub BLIP/=65 K for 0<V/sub b//spl les/3.4 V. The highest value of peak detectivity is D/sub /spl lambda///sup */=5.4/spl times/10/sup 9/ cm/spl radic/Hz/W at V/sub b/=2.9 V and T=77 K, while for T<T/sub BLIP/=65 K, the background-limited detectivity, which exhibits negligible bias dependence, is D/sub BLIP//sup */=3/spl times/10/sup 10/ cm/spl radic/Hz/W.