Optical and electrical properties of chemically deposited CdS thin films modified by air annealing

Author

Gluszak, Edward A. ; Hinckley, Steven

Author_Institution

Center for Very High Speed Microelectron. Syst., Edith Cowan Univ., Joondalup, WA, Australia

fYear

1999

fDate

1999

Firstpage

426

Lastpage

429

Abstract

Polycrystalline CdS thin films have been grown by chemical bath deposition (CBD) using cadmium acetate and thiourea as the Cd and S ion sources. The as-deposited films show a low degree of crystallinity, are very resistive (conductivity ~10^-7 Ω^-1·cm^-1) and possess a small degree of photosensitivity. Air annealing of the films at 100-400°C for 1 hr converts them to n-type through partial conversion of CdS to CdO. This is accompanied by an increase in the photoconductivity by more than 6 orders of magnitude. The optical bandgaps of the as-deposited films were >2.38 eV, which decreased to ~2.24 eV after air annealing

Keywords

II-VI semiconductors; annealing; cadmium compounds; carrier lifetime; energy gap; liquid phase deposition; optical constants; photoconductivity; semiconductor thin films; 100 to 400 degC; 1E-7 (ohmcm)^-1; CdS; air annealing; chemical bath deposition; conductivity; crystallinity; optical bandgap; photoconductivity; photosensitivity; polycrystalline thin films; Annealing; Cadmium compounds; Chemicals; Conductive films; Conductivity; Crystallization; Ion sources; Optical films; Particle beam optics; Sputtering;

fLanguage

English

Publisher

ieee

Conference_Titel

Optoelectronic and Microelectronic Materials Devices, 1998. Proceedings. 1998 Conference on

Conference_Location

Perth, WA

Print_ISBN

0-7803-4513-4

Type

conf

DOI

10.1109/COMMAD.1998.791680

Filename

791680