Title :
Tera-hertz GaAs metal-semiconductor-metal photodetectors with nanoscale finger spacing and width
Author :
Chou, S.Y. ; Liu, Y. ; Fischer, P.B.
Author_Institution :
Dept. of Electr. Eng., Minnesota Univ., Minneapolis, MN, USA
Abstract :
Metal-semiconductor-metal (MSM) photodetectors with nanoscale finger spacing and finger width have been fabricated on MBE (molecular beam epitaxy)-grown GaAs. The smallest finger spacing and width are 25 nm and 15 nm, respectively. Direct dynamic measurement using a femtosecond pulse laser and a 50-GHz sampling oscilloscope showed that the detectors´ speed is much faster than that of the measuring system. Monte Carlo simulations show that, for an MSM photodetector with 25-nm finger spacing, its intrinsic and extrinsic impulse responses are 0.16 ps and 0.25 ps, respectively, and its cut-off frequency is over 1 THz. Finally, the scaling rules in achieving ultra-high-speed MSM photodetectors are discussed.<>
Keywords :
III-V semiconductors; gallium arsenide; measurement by laser beam; metal-semiconductor-metal structures; molecular beam epitaxial growth; nanotechnology; photodetectors; semiconductor epitaxial layers; semiconductor growth; 0.16 to 0.25 ps; 1 THz; 15 nm; 25 nm; 50 GHz; GaAs; MSM photodetector; Monte Carlo simulations; cut-off frequency; dynamic measurement; femtosecond pulse laser; impulse responses; metal-semiconductor-metal photodetectors; molecular beam epitaxy; nanoscale finger spacing; nanoscale finger width; sampling oscilloscope; scaling rules; semiconductors; terahertz photodetectors; ultra-high-speed MSM photodetectors; Fingers; Gallium arsenide; Laser beam cutting; Molecular beam epitaxial growth; Optical pulses; Oscilloscopes; Photodetectors; Pulse measurements; Sampling methods; Velocity measurement;
Conference_Titel :
Electron Devices Meeting, 1991. IEDM '91. Technical Digest., International
Conference_Location :
Washington, DC, USA
Print_ISBN :
0-7803-0243-5
DOI :
10.1109/IEDM.1991.235316
