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:
The initial homoepitaxial growth behavior on nearly on-axis 4H-SiC substrates wasinvestigated. We have observed circular etch pits on the surface of on-axis substrate in the presence ofsource gases. However, there were no circular etch pits on the surface of off-axis substrates. Inaddition, the surface etched by H2 gas did not show circular etch pits even on nearly on-axis substrates.The shape of the circular etch pits was similar to spiral one. The initial growth behavior of epilayerswas also investigated with various C/Si ratios of source gases (0.6〈C/Si〈2.0). The circular etch pitswere observed independent of the source gas ratio. It implies that the source gases promote theselective etching, while the H2 gas etches SiC defect-independent. The spiral shape of etch pits seemsto be produced from the screw dislocation with large burgers vector of micropipes. Therefore, thecircular shape etch pits were not observed in an off-axis substrate
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/02/13/transtech_doi~10.4028%252Fwww.scientific.net%252FMSF.527-529.207.pdf
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