High-speed solar-blind AlGaN Schottky photodiodes
Date
2003Source Title
Proceedings of the Materials Research Society Symposium, MRS 2003
Print ISSN
0272-9172
Publisher
Cambridge University Press
Volume
764
Pages
355 - 360
Language
English
Type
Conference PaperItem Usage Stats
156
views
views
94
downloads
downloads
Abstract
We report high-speed solar-blind AlGaN-based Schottky photodiodes. AlGaN/GaN heterostructure device layers were grown on sapphire substrate. The devices were fabricated on AlGaN/GaN heterostructuresusing a microwave compatible fabrication process. Schottky photodiodes with Au and indium-tin-oxide (ITO) Schottky contacts were fabricated. Current-voltage, spectral responsivity, and high-speed measurements were performed. Both Schottky samples exhibited very low sub-pA dark currents at high reverse bias. A bias dependent spectral responsivity was observed with a peak responsivity of 89 mA/W at 267 nm, and 44 mA/W at 263 nm for Au and ITO-Schottky devices respectively. Time-based high-frequency measurements at 267 nm resulted in pulse responses with rise times and pulse-widths as short as 13 ps and 74 ps respectively. The fastest solar-blind detector had a record 3-dB bandwidth of 1.10 GHz.
Keywords
Aluminum compoundsCrystal structure
Current voltage characteristics
Epitaxial growth
Heterojunctions
Microwaves
Photodetectors
Reactive ion etching
Schottky barrier diodes
Dark currents
Reverse bias
Solar-blind operation
Spectral responsibility
Photodiodes