Optoelectronic properties of expanding thermal plasma deposited textured zinc oxide: Effect of aluminum doping

• Published in: Journal of electronic materials Vol. 35; no. 4; pp. 711 - 716
• Main Authors: Groenen, R., Kieft, E. R., Linden, J. L., Van de Sanden, M. C. M.
• Format: Journal Article
• Language: English
• Published: Warrendale Springer Nature B.V 01.04.2006
• Subjects: Aluminum; Carrier density; Charge density; Chemical vapor deposition; Current carriers; Donors (electronic); Doped films; Electrical resistivity; Glass substrates; Heat conductivity; Morphology; Optical properties; Optoelectronics; Oxide coatings; Semiconductor doping; Spectroellipsometry; Thermal plasmas; Zinc oxide; Zinc oxides
• ISSN: 0361-5235; 1543-186X
• DOI: 10.1007/s11664-006-0126-9

Aluminum-doped zinc oxide films exhibiting a rough surface morphology are deposited on glass substrates utilizing expanding thermal plasma. Spectroscopic ellipsometry is used to evaluate optical and electronic film properties. The presence of aluminum donors in doped films is confirmed by a shift in the zinc oxide bandgap energy from 3.32 to 3.65 eV. In combination with transmission reflection measurements in the visible and NIR ranges, charge carrier densities, optical mobilities, and film resistivities have been obtained from the free carrier absorption. Film resistivities are consistent with direct measurements, values as low as 6.0 × 10^sup -4^ ohm cm have been obtained. The interdependence of electrical conductivity, film composition, and film morphology is addressed. [PUBLICATION ABSTRACT]