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:
Al based alloys, such as Ti/Al, are commonly used for ohmic contacts on p-type SiC.The interfacial structures of a metal alloy film on SiC are very complicated after annealing. Al isconsidered as the key element responsible for forming ohmic contacts on p-type SiC, and reactswith C from SiC and forms Al4C3 and Si during annealing. In this study, we have investigatedohmic contact formation of a single component Al4C3 film on p-type SiC. Based on thestoichiometric formation of Al4C3 between Al and C at high temperatures, several samples withvarious Al/C mole ratios have been examined for ohmic contact formation after different annealingtemperatures. Carbon rich and stoichiometric Al4C3 films form ohmic contacts on p-type 4H-SiC(~2.8 x1018 cm-3 ) after annealing at 800 and 900°C. X-ray diffraction (XRD) data have shown that asingle component Al4C3 is formed when an ohmic contact on p-type SiC is activated. Al/SiC, as thecontrol sample, does not form ohmic contacts under the same conditions. This study reveals thatAl4C3 can be responsible for forming ohmic contacts on p-type SiC. However, its chemicalinstability requires that the secondary metal is necessary to form stable ohmic contacts when Albasedfilms are used
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/02/13/transtech_doi~10.4028%252Fwww.scientific.net%252FMSF.527-529.899.pdf
