Avalanche photodetector in the GaSb/AlSb/InAs material system by molecular beam epitaxy

Xiao-Chang Cheng; Thomas C. McGill Jr.

doi:10.1117/12.344563

7 April 1999 Avalanche photodetector in the GaSb/AlSb/InAs material system by molecular beam epitaxy

Xiao-Chang Cheng, Thomas C. McGill Jr.

Proceedings Volume 3629, Photodetectors: Materials and Devices IV; (1999) https://doi.org/10.1117/12.344563
Event: Optoelectronics '99 - Integrated Optoelectronic Devices, 1999, San Jose, CA, United States

Abstract

GaSb/AlSb/InAs is an attractive system for making low noise avalanche photodetectors (APD) due to possible resonant enhancement of hole impact ionization in Al_xGa_1-xSb and potential enhancement of electron impact ionization in GaSb/AlSb superlattices. We have employed molecular beam epitaxy (MBE) to fabricate device structures so that these effects could be further explored. The devices were grown on GaSb substrates and incorporated a p^-n⁺ one sided abrupt junction. The p^- multiplication region consisted of either bulk Al_0.04Ga_0.96Sb or 10 periods of alternating, 300 angstrom thick GaSb and AlSb layers. A short period, selectively doped InAs/AlSb superlattice was used as the n⁺ layer. Dark current suppression in these devices was found to be largely dependent on the InAs/AlSb superlattice configuration and the resulting band offset at the p^-n⁺ heterojunction. Notably, for devices with a 0.6 micrometer Al_0.04Ga_0.96Sb multiplication region and an optimized InAs/AlSb superlattice, an avalanche break down voltage of 13 V was observed. The dark current density for this device was 6 A/cm² at a multiplication factor of 10. Devices with GaSb/AlSb superlattice multiplication regions exhibited a higher breakdown voltage (18.5 V) and a lower dark current density (0.4 A/cm²) at comparable gain. Impact ionization rates in Al_0.04Ga_0.96Sb were studied by using 781 nm and 1645 nm laser light. The results were consistent with enhancement of hole impact ionization in Al_0.04Ga_0.96Sb.

Citation Download Citation

Xiao-Chang Cheng and Thomas C. McGill Jr. "Avalanche photodetector in the GaSb/AlSb/InAs material system by molecular beam epitaxy", Proc. SPIE 3629, Photodetectors: Materials and Devices IV, (7 April 1999); https://doi.org/10.1117/12.344563

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available