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Author Booker, I. D. ♦ Janzén, E. ♦ Son, N. T. ♦ Hassan, J. ♦ Stenberg, P. ♦ Sveinbjörnsson, E. Ö.
Source United States Department of Energy Office of Scientific and Technical Information
Content type Text
Language English
Subject Keyword CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY ♦ ACTIVATION ENERGY ♦ CARBON ♦ CARRIERS ♦ CROSS SECTIONS ♦ DEEP LEVEL TRANSIENT SPECTROSCOPY ♦ ELECTRON CAPTURE ♦ ELECTRON EMISSION ♦ HOLES ♦ HYDROGEN 4 ♦ RECOMBINATION ♦ SILICON CARBIDES ♦ TEMPERATURE DEPENDENCE ♦ VACANCIES
Abstract Using medium- and high-resolution multi-spectra fitting of deep level transient spectroscopy (DLTS), minority carrier transient spectroscopy (MCTS), optical O-DLTS and optical-electrical (OE)-MCTS measurements, we show that the EH{sub 6∕7} deep level in 4H-SiC is composed of two strongly overlapping, two electron emission processes with thermal activation energies of 1.49 eV and 1.58 eV for EH{sub 6} and 1.48 eV and 1.66 eV for EH{sub 7}. The electron emission peaks of EH{sub 7} completely overlap while the emission peaks of EH{sub 6} occur offset at slightly different temperatures in the spectra. OE-MCTS measurements of the hole capture cross section σ{sub p0}(T) in p-type samples reveal a trap-Auger process, whereby hole capture into the defect occupied by two electrons leads to a recombination event and the ejection of the second electron into the conduction band. Values of the hole and electron capture cross sections σ{sub n}(T) and σ{sub p}(T) differ strongly due to the donor like nature of the deep levels and while all σ{sub n}(T) have a negative temperature dependence, the σ{sub p}(T) appear to be temperature independent. Average values at the DLTS measurement temperature (∼600 K) are σ{sub n2+}(T) ≈ 1 × 10{sup −14} cm{sup 2}, σ{sub n+}(T) ≈ 1 × 10{sup −14} cm{sup 2}, and σ{sub p0}(T) ≈ 9 × 10{sup −18} cm{sup 2} for EH{sub 6} and σ{sub n2+}(T) ≈ 2 × 10{sup −14} cm{sup 2}, σ{sub n+}(T) ≈ 2 × 10{sup −14} cm{sup 2}, σ{sub p0}(T) ≈ 1 × 10{sup −20} cm{sup 2} for EH{sub 7}. Since EH{sub 7} has already been identified as a donor transition of the carbon vacancy, we propose that the EH{sub 6∕7} center in total represents the overlapping first and second donor transitions of the carbon vacancy defects on both inequivalent lattice sites.
ISSN 00218979
Educational Use Research
Learning Resource Type Article
Publisher Date 2016-06-21
Publisher Place United States
Journal Journal of Applied Physics
Volume Number 119
Issue Number 23


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