The optical properties of InGaAsN structures for the fabrication of photodetectors are investigated. An expression for the bulk bandgap as a function of the nitrogen fraction is obtained from x-ray diffraction, photoreflectance and photoluminescence measurements. Optical absorption of undoped MQW structures show that the cutoff wavelength is extended due to the presence of nitrogen. A functioning heterojunction phototransistor was fabricated. Photocurrent spectra show that a responsivity higher than 1.5 A/W is obtained with a cutoff wavelength of 1.16 micrometers . I-V measurements under different light levels show that a peak gain of 5 is obtained with a collector current of 260 (mu) A and a dark current lower than 2 nA with a 10V bias.

Date Published: 12 June 2001
PDF: 8 pages
Proc. SPIE 4288, Photodetectors: Materials and Devices VI, (12 June 2001); doi: 10.1117/12.429411

Published in SPIE Proceedings Vol. 4288:
Photodetectors: Materials and Devices VI
Gail J. Brown; Manijeh Razeghi, Editor(s)