Comparison of ohmic metallization schemes for InGaAlN
- Bell Laboratories, Lucent Technologies, Murray Hill, New Jersey 07974 (United States)
- Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611 (United States)
- Sandia National Laboratories, Albuquerque, New Mexico 87185-0603 (United States)
- Army Research Laboratory, Fort Monmouth, New Jersey 07703 (United States)
W, WSi{sub 0.44}, and Ti/Al contacts were examined on n{sup +}In{sub 0.65}Ga{sub 0.35}N, InN, and In{sub 0.75}Al{sub 0.25}N. W was found to produce low specific contact resistance (q{sub c}{approximately}10{sup {minus}7}{Omega}cm{sup 2}) ohmic contacts to InGaN, while WSi{sub x} showed an as-deposited q{sub c} of 4{times}10{sup {minus}7}{Omega}cm{sup 2} but this degraded significantly with subsequent annealing, reaching 10{sup {minus}5}{Omega}cm{sup 2} at 700{degree}C. Ti/Al contacts on InGaN were stable to {approximately}600{degree}C (q{sub c}{approximately}4{times}10{sup {minus}7}{Omega}cm{sup 2} at {le}600{degree}C). InN contacted with W and Ti/Al produced ohmic contacts with q{sub c}{approximately}10{sup {minus}7}{Omega}cm{sup 2} and for WSi{sub x} q{sub c}{approximately}10{sup {minus}6}{Omega}cm{sup 2} and all three metallization schemes retained values {le}10{sup {minus}6}{Omega}cm{sup 2} up to 600{degree}C. The contact resistances for all of the metals were {ge}10{sup {minus}4}{Omega}cm{sup 2} on InAlN, and degraded with subsequent annealing. WSi{sub x} contacts on InN grown graded from In{sub 0.6}Al{sub 0.4}N were also examined. The specific contact resistance was an order of magnitude lower (q{sub c}{approximately}10{sup {minus}5}{Omega}cm{sup 2}) after 500{degree}C anneal than that measured for WSi{sub x} deposited directly on In{sub 0.6}Al{sub 0.4}N. Measurements of the temperature dependence of these contact structures showed that field emission was generally the most important conduction mechanism. {copyright} {ital 1997 American Vacuum Society.}
- Research Organization:
- Sandia National Laboratory
- DOE Contract Number:
- AC04-94AL85000
- OSTI ID:
- 622657
- Report Number(s):
- CONF-961002--
- Journal Information:
- Journal of Vacuum Science and Technology, A, Journal Name: Journal of Vacuum Science and Technology, A Journal Issue: 3 Vol. 15; ISSN 0734-2101; ISSN JVTAD6
- Country of Publication:
- United States
- Language:
- English
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