Si based Ge1-xSnx photoconductors, with Sn incorporation of 0.9, 3.2, and 7%, were fabricated using a CMOS-compatible process. Temperature dependent study was conducted from 300 to 77 K. The first generation device (standard photoconductor, PD) shows long wavelength cut-off beyond 2.1 μm for 7%-Sn devices at room temperature. The peak responsivity and D* of the 7% Sn device at 1.55 μm were obtained at 77K as 0.08 A/W and 1×10⁹ cm*Hz^1/2*W^-1, respectively. Improved responsivity and specific detectivity (D*) were observed on second generation devices by a newly designed electrode structure (photoconductor with interdigitated electrodes, IEPD). The enhancement factor of responsivity was up to 15 at 77 K.

Date Published: 27 February 2015
PDF: 5 pages
Proc. SPIE 9367, Silicon Photonics X, 93670S (27 February 2015); doi: 10.1117/12.2079580

Published in SPIE Proceedings Vol. 9367:
Silicon Photonics X
Graham T. Reed; Michael R. Watts, Editor(s)