High-performance photovoltaic infrared devices in Hg1−xCdxTe on GaAs

Abstract
A combination of organometallic and isothermal vapor phase epitaxy was used sequentially to grow CdTe and Hg1−xCdxTe on GaAs substrates. Photodiodes in the Hg1−xCdxTe show properties comparable to the best Hg1−xCdxTe grown by liquid phase epitaxy. Resistance‐area products were ≥107 Ω cm2 and >104 Ω cm2 at 77 K for Hg1−xCdxTe with cut‐off wavelength of 3.73 and 5.54 μm at 77 K, respectively. The backside‐illuminated spectral response was broadband with peak external quantum efficiencies typically >50% (without antireflection coating).