Transient photoconductivity of low temperature GaAs grown by molecular beam epitaxy terahertz radar applications

Conference · Tue Dec 31 04:00:00 EST 1991

OSTI ID:10140735

Morse, J D; Mariella, Jr, R P; McConaghy, C F

Optoelectronic sampling techniques have been utilized to characterize transient photoconductivity in low temperature (LT) GaAs grown by molecular beam epitaxy (MBE). Metal-semiconductor-metal (MSM) photoconductive devices have been fabricated on LT-GaAs layers grown at a ``calibrated`` substrate temperature of 190{degrees}C. Results from on-chip photoconductive sampling measurements demonstrate the ability to generate, propagate, and detect photocurrent pulses of {approximately}4ps duration, which is limited by the optoelectronic measurement system. A carrier mobility of 120 cm{sup 2}/V-s has been estimated from these results, which is a factor of 5--10 times larger than alternative materials used for picosecond photoconductivity. This translates to improved sensitivity for emission and detection of terahertz pulses of electromagnetic (EM) radiation. 10 refs.

• Research Organization: Lawrence Livermore National Lab., CA (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 10140735
• Report Number(s): UCRL-JC--108738; CONF-911267--3; ON: DE92011848
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360606
42 ENGINEERING
426000
COMPONENTS
ELECTRON DEVICES AND CIRCUITS
DETECTION
ELECTROMAGNETIC RADIATION
GALLIUM ARSENIDES
MOLECULAR BEAM EPITAXY
PHOTOCONDUCTIVITY
PHOTOCONDUCTORS
PHYSICAL PROPERTIES
PULSES
RADAR
SEMICONDUCTOR SWITCHES