Characteristics of current filaments in GaAs photoconductive semiconductor switches
- Sandia National Labs., Albuquerque, NM (United States)
Infrared images of GaAs photoconductive semiconductor switches (PCSS) show current filamentation during high gain switching. Since high speed switching characteristics for these devices are related to the initiation and control of these filaments, many experiments have been performed to determine how such control can be achieved. The experiments reported here use fiber-optic coupled laser diode arrays (LDA) to initiate switching and to control the location and number of current filaments. This paper describes the nature of these current filaments as the fiber-optic configuration and the switch test parameters are varied. These experiments show that fiber-optic coupled LDAs can be configured to make efficient use of the optical trigger energy, control the current flow, and improve overall switch performance. One unusual property of the current filaments is that their rate of formation is much faster than the saturation carrier velocity in GaAs. This paper will present results from direct measurements of the filament growth velocity which indicate velocities up to 2 {times} 10{sup 9} cm/s. The implications of this result on several models for the initiation of high gain switching will be discussed.
- Research Organization:
- Sandia National Laboratories (SNL), Albuquerque, NM, and Livermore, CA (United States)
- DOE Contract Number:
- AC04-94AL85000
- OSTI ID:
- 51765
- Report Number(s):
- CONF-940604-; ISBN 0-7803-2006-9; TRN: IM9524%%233
- Resource Relation:
- Conference: 1994 Institute of Electrical and Electronic Engineers (IEEE) international conference on plasma science, Santa Fe, NM (United States), 6-8 Jun 1994; Other Information: PBD: 1994; Related Information: Is Part Of IEEE conference record -- Abstracts; PB: 252 p.
- Country of Publication:
- United States
- Language:
- English
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