Electrical characterization of titanium-based ohmic contacts to 4H-Silicon carbide for high-power and high-temperature operation
2002 (English)In: Journal of the Korean Physical Society, ISSN 0374-4884, Vol. 40, no 4, 572-576 p.Article in journal (Refereed) Published
We report on titanium-based ohmic contacts (titanium carbide. titanium tungsten, and titanium) on both highly doped epilayers (n(+) and p(+)) and Al-ion-implanted layers. The TiC contact layer was epitaxially grown on epilayers as well as an Al-ion-implanted layers of 4H-SiC by co-evaporation Ti and C-60 under an ultra-high vacuum condition at low temperature (<500 degreesC). For comparison and long-term stability test, we also deposited TiW (weight ratio 30 : 710) ohmic contacts to p and n-type epilayers of 4H-SiC. The specific contact resistances (p(c)) were found to be as low as p- 5X10(-6), 2x10(-5), 2x10(-5), 3x10(-4), 4x10(-5), and 1X10(-4) Omegacm(2) for TiC contacts to n(+) epilayers, p(+) epilayers, and Al-ion-implanted layers, Ti contacts to p(+) epilayers, and TiW contacts to p(+) and to n(+) epilayers, respectively, by using linear transmission line method (TLM) measurements. During the long-term reliability tests in a vacuum chamber, we found that evaporated Au capping layers helped to keep the contacts from degrading.
Place, publisher, year, edition, pages
2002. Vol. 40, no 4, 572-576 p.
Ohmic contacts, 4H-silicon carbide, Long-term reliability, silicon-carbide
IdentifiersURN: urn:nbn:se:kth:diva-21471ISI: 000175022300007OAI: oai:DiVA.org:kth-21471DiVA: diva2:340169
QC 201005252010-08-102010-08-10Bibliographically approved