Metal-Grating-Coupled Terahertz Quantum-Well Photodetectors

• Published in: IEEE electron device letters 2011-05, Vol.32 (5), p.659-661
• Main Authors: Zhang, R, Guo, X G, Song, C Y, Buchanan, M, Wasilewski, Z R, Cao, J C, Liu, H C
• Format: Article
• Language: English
• Subjects: Aluminum gallium arsenides; Applied sciences; Circuit properties; Compound structure devices; Couplings; Cross-disciplinary physics: materials science; rheology; Detector; Detectors; Diffraction gratings; Electric, optical and optoelectronic circuits; Electronics; Exact sciences and technology; Gallium arsenide; grating; Gratings; Gratings (spectra); Joining; Materials science; Metals; Microwave circuits, microwave integrated circuits, microwave transmission lines, submillimeter wave circuits; Nanoscale materials and structures: fabrication and characterization; Optoelectronic devices; Photodetectors; Physics; quantum well (QW); Quantum wells; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; terahertz (THz)
• ISSN: 0741-3106; 1558-0563
• DOI: 10.1109/LED.2011.2112632

Three terahertz (THz) GaAs/AlGaAs quantum-well photodetectors with different 1-D metal gratings are fabricated for front-incident detection of THz waves. Photocurrent spectra are acquired and compared with 45° incident facet samples (without grating), and peak responsivities are determined with a calibrated blackbody radiation source. The results show that these gratings can couple THz waves into detectors effectively, resulting in good detector responsivities. The modal method is employed to simulate the light coupling efficiency and the optimization conditions of the gratings.