Share Email Print

Proceedings Paper

Ultrafast resonant-cavity-enhanced Schottky photodiodes
Author(s): M. Selim Unlu; Bora M. Onat; Mutlu Goekkavas; Ekmel Ozbay; Erhan P. Ata; Elias Towe; Gary Tuttle; Richard P. Mirin; David H. Christensen
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

Resonant cavity enhanced (RCE) photodiodes are promising candidates for applications in optical communications and interconnects where ultrafast high-efficiency detection is very desirable. In RCE structures, the electrical function of the photodiode is largely unchanged, but optically it is subject to the effects of the cavity, mainly wavelength selectivity and a large enhancement of the resonant optical field. The increased optical field allows photodetectors to be made thinner and therefor faster in the transit-time limited operation, while simultaneously maintaining a high quantum efficiency at the resonant wavelengths. The combination of RCE detection scheme with Schottky photodiodes allows for fabrication of high-performance photodetectors with relatively simple material structure and fabrication process. In RCE Schottky photodiodes, a semi-transparent metalization can be used simultaneously as the electrical contact and the top reflector for the resonant cavity. Device performance is optimized by varying the thickness of the Schottky metalization and utilizing a dielectric matching layer. We present theoretical and experimental results on spectral and high-speed properties. We have demonstrated RCE Schottky photodiodes in (Al, In)GaAs/GaAs material system with temporal response of 10 ps full-width-at-half-maximum. These results were measurement setup limited and a conservative estimation of the bandwidth corresponds to more than 100 GHz. The photodiodes were designed and fabricated for 900 nm and 840 nm resonant wavelengths. The best measured quantum efficiency is around 50% which is slightly less than the theoretical prediction for these devices.

Paper Details

Date Published: 22 December 1997
PDF: 9 pages
Proc. SPIE 3290, Optoelectronic Integrated Circuits II, (22 December 1997);
Show Author Affiliations
M. Selim Unlu, Boston Univ. (United States)
Bora M. Onat, Boston Univ. (United States)
Mutlu Goekkavas, Boston Univ. (United States)
Ekmel Ozbay, Bilkent Univ. (Turkey)
Erhan P. Ata, Bilkent Univ. (United States)
Elias Towe, Univ. of Virginia (United States)
Gary Tuttle, Iowa State Univ. (United States)
Richard P. Mirin, National Institute of Standards and Technology (United States)
David H. Christensen, National Institute of Standards and Technology (United States)

Published in SPIE Proceedings Vol. 3290:
Optoelectronic Integrated Circuits II
Shih-Yuan Wang; Yoon-Soo Park, Editor(s)

© SPIE. Terms of Use
Back to Top
Sign in to read the full article
Create a free SPIE account to get access to
premium articles and original research
Forgot your username?