Electric Field Enhancement of Electron Emission Rates from Z(1/2) Centers in 4H-SiC

Authors

A. O. Evwaraye
S. R. Smith
William C. Mitchel
Gary C. Farlow, Wright State University - Main CampusFollow

Document Type

Article

Publication Date

9-1-2009

Abstract

Z_1/2 defect centers were produced by irradiating 4H-SiC bulk samples with 1 MeV electrons at room temperature. The emission rate dependence on the electric field in the depletion region was measured using deep level transient spectroscopy and double-correlation deep level transient spectroscopy. It is found that the Z_1/2 defect level shows a strong electric field dependence with activation energy decreasing from E_c−0.72 eV at zero field to E_c−0.47 eV at 6.91×10⁵ V/cm. The phonon assisted tunneling model of Karpus and Perel [Sov. Phys. JETP 64, 1376 (1986) ] completely describes the experimental data. This model describes the dependence of the emission rate on electric field F as e_n(F) = e_no exp(F²/Fc2), where F_c is the characteristic field that depends on the phonon assisted tunneling time τ₂. The values of F_c and τ₂ were determined and the analysis of the data leads to the suggestion that Z_1/2 may be a substitutional point defect.

Comments

Copyright © 2009, American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in the Journal of Applied Physics 106.6, and may be found at http://jap.aip.org/resource/1/japiau/v106/i6/p063702_s1

Repository Citation

Evwaraye, A. O., Smith, S. R., Mitchel, W. C., & Farlow, G. C. (2009). Electric Field Enhancement of Electron Emission Rates from Z(1/2) Centers in 4H-SiC. Journal of Applied Physics, 106 (6), 63702.
https://corescholar.libraries.wright.edu/physics/163

DOI

10.1063/1.3224872