Comparison of Electrical Properties of Ohmic Contact Realized on p-Type 4H-SiC
N+ 4H-SiC commercial substrates with n-type epilayers have been used to realize bipolar diodes and TLM structures. The p-type emitter of diodes was realized by Al implantations followed by a post-implantation annealing with or without a graphite capping layer. Ohmic contacts were formed by depositin...
Gespeichert in:
Veröffentlicht in: | Materials science forum 2009-01, Vol.600-603, p.639-642 |
---|---|
Hauptverfasser: | , , , , |
Format: | Artikel |
Sprache: | eng |
Schlagworte: | |
Online-Zugang: | Volltext |
Tags: |
Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
|
Zusammenfassung: | N+ 4H-SiC commercial substrates with n-type epilayers have been used to realize bipolar
diodes and TLM structures. The p-type emitter of diodes was realized by Al implantations followed
by a post-implantation annealing with or without a graphite capping layer. Ohmic contacts were
formed by depositing Ti/Ni on the backside and Ni/Al on the topside of the wafer. It appears that
capping the sample during the annealing reduces considerably the surface roughness and the specific
contact resistance. Sheet resistance and specific contact resistance as low as 2kΩ/□ and respectively
1.75×10-4 Ωcm² at 300 K have been obtained. I-V measurements as a function of temperature have
been performed from ~100 to ~500 K. The variations of the series resistance vs. temperature can be
explained by the freeze-out of carriers and by the variation of carrier mobility. |
---|---|
ISSN: | 0255-5476 1662-9752 1662-9752 1662-9760 |
DOI: | 10.4028/www.scientific.net/MSF.600-603.639 |