Thermally stable, highly conductive, and transparent ZnO layers prepared in situ by chemical vapor deposition

It is possible to fabricate thin epitaxial ZnO layers doped in situ with In and Ga impurities by chemical vapor deposition (CVD) in a low-pressure sys tem. Highly conductive and transparent ZnO:Me (0.1-2 wt.%) films are deposi ted on (1012) sapphire substrates. Electrical, optical, and structural prop erties of the films are investigated. The ZnO:Me thin epitaxial layers (TEL ) features unique thermal stability of their electric properties to thermoc yclings within the 300-950 K temperature range in various ambient. It is fo und that the crystal structure perfection must be among the main factors co nditioning the thermal stability of the films. It is suggested a formation of metal cluster structures-whiskers over the doped film surface. (C) 1999 Elsevier Science S.A. All rights reserved.