Solar-blind AlGaN-based Schottky photodiodes with low noise and high detectivity
Date
2002
Editor(s)
Advisor
Supervisor
Co-Advisor
Co-Supervisor
Instructor
Source Title
Applied Physics Letters
Print ISSN
0003-6951
Electronic ISSN
Publisher
American Institute of Physics
Volume
81
Issue
17
Pages
3272 - 3274
Language
English
Type
Journal Title
Journal ISSN
Volume Title
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Abstract
We report on the design, fabrication, and characterization of solar-blind Schottky photodiodes with low noise and high detectivity. The devices were fabricated on n-/n+ AlGaN/GaN heterostructures using a microwave compatible fabrication process. True solar-blind operation with a cutoff wavelength of ∼274nm was achieved with AlxGa1-xN (x=0.38) absorption layer. The solar-blind detectors exhibited <1.8nA/cm2 dark current density in the 0-25 V reverse bias regime, and a maximum quantum efficiency of 42% around 267 nm. The photovoltaic detectivity of the devices were in excess of 2.6×1012cmHz1/2/W, and the detector noise was 1/f limited with a noise power density less than 3×10-29A2/Hz at 10 kHz. © 2002 American Institute of Physics.