InAs p-n diodes grown on GaAs and GaAs-coated Si by molecular beam epitaxy

Abstract
InAs pn diodes have been grown on GaAs and GaAs‐coated Si substrates by molecular beam epitaxy. Transmission electron microscopy cross sections of the epilayers demonstrate a good structural quality. Photodiodes were obtained using a Be (p=5×1016 cm−3) and Si (n=3×1016 cm−3) doping scheme. The diodes exhibited 77 K zero‐bias resistance area products of 2200 Ω cm2 for InAs/GaAs and 1500 Ω cm2 for InAs/GaAs/Si. The spectral response of the devices peaked at 2.95 μm with Johnson noise limited detectivities D* of 7.0×1011 cm Hz1/2/W for InAs/GaAs and 5.8×1011 cm Hz1/2/W for InAs/GaAs/Si. These results clearly demonstrate the feasibility of the monolithic integration of InAs infrared detectors and GaAs or Si read‐out electronics.