| AVS 63rd International Symposium & Exhibition | |
| Electronic Materials and Photonics | Friday Sessions |
| Session EM-FrM |
| Session: | Late Breaking News on Electronic Materials and Devices |
| Presenter: | Dilip Chauhan, Georgia State University |
| Authors: | D. Chauhan, Georgia State University A.G.U. Perera, Georgia State University L.H. Li, University of Leeds, United Kingdom L. Chen, University of Leeds, United Kingdom E.H. Linfield, University of Leeds, United Kingdom |
| Correspondent: | Click to Email |
p-GaAs/AlxGa1-xAs heterojunction is an attractive material system due to its mature III-V material growth and processing technology. Infrared detection in the mid-infrared range is possible by exploiting the intra-valance band hole transitions in the light hole/heavy hole and spin-orbit split-off bands. The wavelength threshold can be tuned by varying the Al mole fraction (x), while graded AlxGa1-xAs potential barriers create an asymmetry to allow a photovoltaic operation. The operation under photovoltaic mode is advantageous due to thermal noise limited performance. In a preliminary study in a 2 – 6 µm photovoltaic detector, we implemented a current blocking barrier, which improved the specific detectivity by two orders of magnitude, to 1.9×1011 Jones at 2.7 µm, at 77K. At zero bias, the resistance-area product (R0A) had a value of ~ 7.2×108 Ω cm2, which is five orders higher in magnitude compared to the R0A value without the blocking barrier. A photoresponse was observed up to 130K. Further work is in progress to optimize the detector at a higher operating temperature.
Acknowledgement: This work was supported in part by the U.S. Army Research Office under Grant No. W911 NF-15-1-0018, and in part by National Science Foundation (NSF) under Grant No. ECCS-1232184.