A high-gain, modulation-doped photodetector using low-temperature MBE-grown GaAs

• Published in: IEEE electron device letters Vol. 16; no. 1; pp. 20 - 22
• Main Authors: Subramanian, S., Schulte, D., Ungier, L., Zhao, P., Plant, T.K., Arthur, J.R.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.01.1995; Institute of Electrical and Electronics Engineers
• Subjects: Annealing; Applied sciences; Electronics; Electrons; Epitaxial layers; Exact sciences and technology; Gallium arsenide; HEMTs; Heterojunctions; MODFETs; Molecular beam epitaxial growth; Optoelectronic devices; Photodetectors; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Substrates; Binary compound; Voltage current curve; Cross section; Infrared detection; Modulation doping; Photodetector; III-V compound; Spectral data; Gallium Arsenides; Field effect transistor; Manufacturing process; Molecular beam condensation; Low temperature
• ISSN: 0741-3106; 1558-0563
• DOI: 10.1109/55.363212

We report the fabrication and performance of a novel, high gain photodetector. Basically, the device is a modulation-doped field effect transistor (MODFET) structure with its channel region made of low-temperature MBE-grown GaAs. It exhibits an excellent responsivity of 65 A/W at /spl sim/0.87 μm and 6.5 A/W at /spl perp/1.0 μm. In the sub-bandgap range (0.9-1.3 μm) the responsivity of this device is the highest ever reported, to our knowledge, for any GaAs-based device. Thus, the device appears to be ideally suited for applications requiring a high photodetection sensitivity, especially in the 1.3 μm wavelength region. Charge separation by the built-in field normal to the heterojunction plane is attributed to be responsible for the gain in the device.