Conditions for a carrier multiplication in amorphous-selenium based photodetector

Journal Article · Mon Feb 18 00:00:00 EST 2013 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4793487· OSTI ID:22162752

Masuzawa, Tomoaki; Kuniyoshi, Shingo; Onishi, Masanori; Kato, Richika; Saito, Ichitaro; Okano, Ken ^[1]; Yamada, Takatoshi ^[2]; Koh, Angel T. T.; Chua, Daniel H. C. ^[3]; Shimosawa, Tatsuo ^[4]

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1. Department of Material Science, International Christian University, S102 Science Hall, ICU, 3-10-2 Osawa, Mitaka, Tokyo 181-8585 (Japan)
2. Nanotube Research Center, National Institute of Advanced Industrial Science and Technology (AIST), AIST Tsukuba Central 5, Tsukuba, Ibaraki 305-8568 (Japan)
3. Department of Materials Science and Engineering, National University of Singapore, 7 Engineering Drive 1, Singapore 117574 (Singapore)
4. Department of Clinical Laboratory, Faculty of Medicine, University of Tokyo, 7-3-1 Hongo, Bunkyoku, Tokyo 113-8655 (Japan)

Amorphous selenium is a promising candidate for high sensitivity photodetector due to its unique carrier multiplication phenomenon. More than 10 carriers can be generated per incident photon, which leads to high photo-conversion efficiency of 1000% that allows real-time imaging in dark ambient. However, application of this effect has been limited to specific devices due to the lack in material characterization. In this article, mechanism of carrier multiplication has been clarified using time-of-flight secondary ion mass spectroscopy and Raman spectroscopy. A prototype photodetector achieved photo conversion efficiency of 4000%, which explains the signal enhancement mechanism in a-Se based photodetector.

• OSTI ID: 22162752
• Journal Information: Applied Physics Letters, Vol. 102, Issue 7; Other Information: (c) 2013 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
AMORPHOUS STATE
CARRIER DENSITY
CARRIERS
CONVERSION
EFFICIENCY
ION MICROPROBE ANALYSIS
MASS SPECTRA
MASS SPECTROSCOPY
PHOTODETECTORS
PHOTONS
RAMAN SPECTRA
RAMAN SPECTROSCOPY
REAL TIME SYSTEMS
SELENIUM
SENSITIVITY
TIME-OF-FLIGHT METHOD