Demonstration of InAsBi photoresponse beyond 3.5µm

Result date: 01/01/2014
Author: I. C. Sandall,
Institute: Department of Electronic and Electrical Engineering, The University of Sheffield, Sir Frederick Mappin Building, Mappin Street, Sheffield S1 3JD, United Kingdom
Publication: Appl. Phys. Lett.
Instrument: MBE Systems
An Indium Arsenide Bismide photodiode has been grown, fabricated, and characterized to evaluate its performance in the Mid Wave Infrared region of the spectrum. Spectral response from the diode has been obtained up to a diode temperature of 225?K. At this temperature, the diode has a cut off wavelength of 3.95 µm, compared to 3.41 µm in a reference Indium Arsenide diode, indicating that Bismuth has been incorporated to reduce the band gap of Indium Arsenide by 75?meV. Similar band gap reduction was deduced from the cut off wavelength comparison at 77K. From the dark current data, shunt resistance values of 8 and 39 O at temperatures of 77 and 290?K, respectively, were obtained in our photodiode.