In this paper, a high detectivity THZ-IR photodetector based on resonant tunneling spherical centered defect quantum dot (RT-SCDQD) is investigated. Inserting the centered defect in quantum dot, increases the dipole transition matrix element and so increases the absorption coefficient considerably (1.05x10⁶~7.33x10⁶ m^-1 at 83μm). Therefore the quantum efficiency in SCDQD structure enhances which leads to increasing the responsivity of the proposed system. We propose a method for implementation of this complex quantum dot. Attaching the resonant tunneling double barrier to the quantum dot removes the basic problem of electron collection from deep excited state without applying large bias voltages. Also, application of the double barrier reduces the dark current. These improvements conclude to ultra high detectivity of 2.25x10⁹ cmHz^1/2/W at 300°K and 83μm respectively.

Date Published: 18 November 2008
PDF: 9 pages
Proc. SPIE 7135, Optoelectronic Materials and Devices III, 71352Z (18 November 2008); doi: 10.1117/12.800779

Published in SPIE Proceedings Vol. 7135:
Optoelectronic Materials and Devices III
Yi Luo; Jens Buus; Fumio Koyama; Yu-Hwa Lo, Editor(s)