Double-barrier long wavelength SiGe/Si heterojunction internal photoemission infrared photodetectors

Aslan, B
Turan, Raşit
Liu, HC
Baribeau, JM
Buchanan, M
Chow-Chong, P
This work studies the effect of a double barrier on the photoresponse spectrum of SiGe/Si heterojunction internal photoemission infrared photodetectors. Results are compared with those of a single barrier sample which has nominally the same parameters. It is shown that the cut-off wavelength of the multi-barrier device depends on the operating temperature; therefore, it can be tuned to the desired region within the device capacity by changing the device temperature. The proof of concept device, which has two Si1-xGex/Si junctions with x=0.1 and x=0.23, allows the tuning of the cut-off wavelength from 19.9 mum to 11.7 mum for 10 K and 50 K, respectively.


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Citation Formats
B. Aslan, R. Turan, H. Liu, J. Baribeau, M. Buchanan, and P. Chow-Chong, “Double-barrier long wavelength SiGe/Si heterojunction internal photoemission infrared photodetectors,” APPLIED PHYSICS B-LASERS AND OPTICS, pp. 225–228, 2004, Accessed: 00, 2020. [Online]. Available: