ISSN:
1662-9752
Source:
Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Deep levels in as-grown p-type 4H-SiC epilayers have been investigated by DLTS. Threedeep hole traps (HK2, HK3 and HK4) can be detected by DLTS in the temperature range from 350Kto 700K. They are energetically located at 0.84 eV (HK2), 1.27 eV (HK3) and 1.44 eV (HK4) abovethe valence band edge. The activation energy of the traps does not show any meaningful changeregardless of applied electric field, indicating that the charge state of the deep hole traps may beneutral after hole emission (donor-like). By the low-energy electron irradiation, the HK3 and HK4concentrations are significantly increased, suggesting that the origins of the HK3 and HK4 may berelated to carbon displacement. Study on the thermal stability of these hole traps has revealed that thetrap concentrations of HK3 and HK4 are reduced to below the detection limit (1-2 × 1011 cm-3) byannealing at 1350°C. The HK2 is thermally more stable than HK3 and HK4, and becomes lower thanthe detection limit by annealing at 1550°C
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/02/13/transtech_doi~10.4028%252Fwww.scientific.net%252FMSF.527-529.501.pdf
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