Title :
Optoelectronic properties of nanocrystalline tungsten oxide thin films
Author :
Jayatissa, Ahalapitiya H. ; Cheng, Shih-Te
Author_Institution :
Mater. Sci. & Eng., Coll. of Eng. & Appl. Sci., Kalamazoo, MI, USA
Abstract :
Tungsten oxide (WO3) is an important electronic material investigated for solid state sensors, electrochromic and optoelectronic devices. In this study, optoelectronic properties of nanocrystalline WO3 thin films, prepared by vacuum evaporation followed by thermal annealing were investigated. The structural and optoelectronic properties were measured for systematically annealed samples in 100-600°C range. It was found that the optical transmittance and electrical conductivity were varied in 10-80% range and 10-3- 10-8 (Ω.cm)-1 range, respectively, by change of annealing temperature. Study of surface and structural properties reveals that pronounced effect on properties can be made by annealing even at 100°C. Results indicated that the properties Of WO3 can be tuned by annealing process because of change of crystallinity from amorphous to nanomonocrystalline to polycrystalline structures.
Keywords :
annealing; electrical conductivity; light transmission; nanostructured materials; semiconductor materials; semiconductor thin films; surface structure; tungsten compounds; vacuum deposited coatings; 100 to 600 degC; 10-3 to 10-8 ohmcm; WO3; amorphous structures; annealed samples; annealing temperature; crystallinity; electrical conductivity; electrochromic devices; monocrystalline structures; nanocrystalline tungsten oxide thin films; optical transmittance; optoelectronic devices; optoelectronic properties; polycrystalline structures; solid state sensors; structural properties; surface properties; thermal annealing; vacuum evaporation; Annealing; Conductivity; Electrochromism; Optical films; Optical sensors; Optoelectronic and photonic sensors; Optoelectronic devices; Solid state circuits; Transistors; Tungsten;
Conference_Titel :
Nanotechnology, 2002. IEEE-NANO 2002. Proceedings of the 2002 2nd IEEE Conference on
Print_ISBN :
0-7803-7538-6
DOI :
10.1109/NANO.2002.1032115
