The barrier enhanced InAs/GaSb long wavelength photodetectors were designed and demonstrated in this paper. A PBIN detector with an electron barrier inserted between P type contactor and absorption region show significantly improved electrical performances compared to a PIN structure. The R_maxA product of the PBIN detector was measured to be 104 Ωcm² at 80K and 7360 Ωcm² at 50K. Temperature dependent measurements show that the tunneling currents dominate the dark current below 50K, the generation-recombination (GR) currents dominate from 50K to 90K, and the diffusion current dominate over 90K. The PBIN structure benefits from a lower electric field in the absorption region and therefore, suppressed the tunnel currents and GR currents. To improve the quantum efficiency, Be-doping was employed to convert the conductivity of the long wavelength SL structure, the PN junction moves away from the B-I hetrostructure to the π-N interface, which loses the barrier effect. Therefore, the hole barrier was needed to form a PBπBN structure. In this paper, hole barrier was designed without Al element to form a PBπBN structure. The R_maxA product of the PBπBN detector was measured to be 77 Ωcm² and the dark current density under -0.05V bias was measured to be 8.8×10^-4A/cm² at 80K. The peak current responsivity at 9.8 μm was 2.15A/W and the quantum efficiency was 26.7%.

Date Published: 13 April 2015
PDF: 6 pages
Proc. SPIE 9522, Selected Papers from Conferences of the Photoelectronic Technology Committee of the Chinese Society of Astronautics 2014, Part II, 952223 (13 April 2015); doi: 10.1117/12.2180425

Published in SPIE Proceedings Vol. 9522:
Selected Papers from Conferences of the Photoelectronic Technology Committee of the Chinese Society of Astronautics 2014, Part II
Xiangwan Du; Jennifer Liu; Dianyuan Fan; Jialing Le; Yueguang Lv; Jianquan Yao; Weimin Bao; Lijun Wang, Editor(s)