Graphene-Based Field-Effect Photodetector with HgCdTe Absorber

• Published in: Journal of electronic materials Vol. 53; no. 10; pp. 5865 - 5873
• Main Authors: Sheremet, Volodymyr, Rabbe, Md Fazle, Jacobs, Randy N., Avrutin, Vitaliy, Ӧzgür, Ümit, Dhar, Nibir K.
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.10.2024; Springer Nature B.V
• Subjects: Aluminum oxide; Bilayers; Characterization and Evaluation of Materials; Chemical vapor deposition; Chemistry and Materials Science; Contact resistance; Electric potential; Electronics and Microelectronics; Fourier transforms; Graphene; Infrared radiation; Instrumentation; Materials Science; Mercury cadmium tellurides; Optical and Electronic Materials; Phosphorus; Photometers; Radiation; Sensors; Silicon substrates; Solid State Physics; Temperature; Topical Collection: 2023 U.S. Workshop on Physics and Chemistry of II-VI Materials; U.S. Workshop on the Physics and Chemistry of II-VI Materials 2023; Voltage; HgCdTe; phototransistor; Photodetector; graphene
• ISSN: 0361-5235; 1543-186X
• DOI: 10.1007/s11664-024-11314-3

A field-effect photodetector structure composed of an Al 2 O 3 -encapsulated bilayer graphene conductive channel attached to an Al 2 O 3 dielectric layer deposited on a HgCdTe absorbing layer on CdTe/Si was studied. Ti/Au ohmic contacts to the graphene layer were used as drain and source electrodes and back-gate voltage was applied to the Si substrate. It was demonstrated that 80% and 10% modulation of the graphene channel conductivity can be achieved under blue (50 W/cm 2 ) and infrared (IR) (0.02 W/cm 2 ) illumination, respectively, at a gate voltage of 7 V. Detector responsivity was measured as 406 A/W and 1.83 A/W under IR lamp and 405-nm laser irradiation, respectively, with corresponding gain values of 340 and 5.6. The detectivity of the 4 × 4 photodetector arrays was on the order of 10 10 Jones for the mid-wave infrared wavelength range (3–5 μm).