Structural, compositional, optical, and electrical properties of solution-grown ZnxCd1-xS films

Thin films of zinc cadmium sulfide (ZnxCd1-xS) have been prepared in the entire range from ZnS to CdS by using a chemical solution growth technique. Structural, compositional, optical, and electrical properties of thin films of ZnxCd1-xS have been studied as a function of x. X-ray studies show that as-grown films are composed of a hexagonal phase in the range 0 less than or equal to x < 0.5 and a cubic sphalerite phase for x greater than or equal to 0.5. Film optical parameters (n, k, alpha, E-g) were evaluated and correlated with the composition ratio, x. These studies show that ZnxCd1-xS films of different compositions have two direct transitions with corresponding energy gaps E-g and E-g + Delta S-0. The variations in E-g and E-g + Delta S-0 with x indicate that ZnxCd1-xS is an amalgamation type following quadratic equations with bowing parameters 0.3 and 0.5, respectively. The resistivity of solution-grown ZnxCd1-xS films was found to increase with increasing x. The effect of boron doping on electrical properties was also investigated. (C) 2000 The Electrochemical Society. S0013-4651(99)01-036-8. All rights reserved.