Electronic transport in thermally crystallized SiC films on sapphire

✍ Scribed by W. Hellmich; G. Müller; G. Krötz; G. Derst; S. Kalbitzer

• Publisher: Elsevier Science
• Year: 1995
• Tongue: English
• Weight: 308 KB
• Volume: 29
• Category: Article
• ISSN: 0921-5107
• DOI: 10.1016/0921-5107(94)04026-z

✦ Synopsis

Fine-grained (d=0.1 /~m), polycrystalline (pc) SiC films were prepared on top of insulating and optically transparent sapphire substrates by a thermal crystallization technique (SiCOS films). Unlike high-temperature deposited pc-SiC films, SiCOS films exhibit a very low d.c. conductivity in the dark (a ~-10-s ~-1 cm-l) and an efficient photoconductivity on illumination with short-wavelength UV light. Relatively high n-or p-type conductivities (o = 1 Q J cm ' ) were obtained after implantation of N, P and AI ions. It is argued that the electronic transport in the thermally crystallized films is limited by a grain-boundary-dominated conduction process in which thermal activation across potential barriers competes with tunnelling through these same barriers.