Electrical activation of high concentrations of N+ and P+ ions implanted into 4H-SiC
2002 (English)In: Journal of Applied Physics, ISSN 0021-8979, E-ISSN 1089-7550, Vol. 92, no 1, 549-554 p.Article in journal (Refereed) Published
Comparative Hall effect investigations are conducted on N- and P-implanted as well as on (N+P)-coimplanted 4H-SiC epilayers. Box profiles with three different mean concentrations ranging from 2.5x10(18) to 3x10(20) cm(-3) to a depth of 0.8 mum are implanted at 500 degreesC into the (0001)-face of the initially p-type (Al-doped) epilayers. Postimplantation anneals at 1700 degreesC for 30 min are conducted to electrically activate the implanted N+ and P+ ions. Our systematic Hall effect investigations demonstrate that there is a critical donor concentration of (2-5)x10(19) cm(-3). Below this value, N- and P-donors result in comparable sheet resistances. The critical concentration represents an upper limit for electrically active N donors, while P donors can be activated at concentrations above 10(20) cm(-3). This high concentration of electrically active P donors is responsible for the observed low sheet resistance of 35 Omega/square, which is about one order of magnitude lower than the minimum sheet resistance achieved by N implantation.
Place, publisher, year, edition, pages
2002. Vol. 92, no 1, 549-554 p.
phosphorus implantation, 4h-silicon carbide, growth, donors, endor, epr
IdentifiersURN: urn:nbn:se:kth:diva-21627DOI: 10.1063/1.1479462ISI: 000176314800087OAI: oai:DiVA.org:kth-21627DiVA: diva2:340325
QC 201005252010-08-102010-08-10Bibliographically approved