Title :
Selective electron beam irradiation of high purity semi-insulating 4H silicon carbide substrates to characterize the effects on photoconductive semiconductor switch operation
Author :
Bullick, A. ; Mauch, D. ; Sullivan, W. ; Dickens, J.
Author_Institution :
Dept. of Electr. & Comput. Eng., Texas Tech Univ., Lubbock, TX, USA
Abstract :
High energy electron beam irradiation of bulk SiC creates crystal defects within the material which act as deep traps. These deep traps capture charge carriers and in turn increase the resistivity/blocking voltage of SiC photoconductive semiconductor switches (PCSS). Irradiation has been reported to increase the blocking field of a vertical SiC PCSS to 705 kV/cm when the entire sample region is irradiated with a 1×1018 cm-2 dose from a 1 MeV electron beam1. This paper investigates selectively irradiating specific regions of a SiC PCSS gap to characterize the effects on DC operation. Lateral switches were fabricated on a high-purity semi-insulating 4H-SiC sample and subsequently irradiated to form three sample types of differing irradiation regions. The selectively irradiated regions are: 1) mid-gap, 2) both contact-gap interfaces, and 3) a single gap-contact interface used for both anode and cathode testing configurations depending upon the polarity of the applied voltage.
Keywords :
crystal defects; electrical resistivity; electron beam effects; optical fabrication; optical switches; photoconducting switches; silicon compounds; wide band gap semiconductors; DC operation; SiC; anode testing; applied voltage polarity; blocking voltage; bulk SiC; cathode testing; charge carriers; crystal defects; deep traps; electron volt energy 1 MeV; high energy electron beam irradiation; high purity semiinsulating 4H silicon carbide substrates; lateral switches; mid-gap interface; photoconductive semiconductor switch operation; resistivity; single gap-contact interface; vertical SiC PCSS; Electron beams; Electron traps; Radiation effects; Silicon carbide; Substrates; Switches; Switching circuits;
Conference_Titel :
Plasma Science (ICOPS), 2013 Abstracts IEEE International Conference on
Conference_Location :
San Francisco, CA
DOI :
10.1109/PLASMA.2013.6633401