Micro-crystallographic and optical studies on Cd sub(1-x)Zn sub(x)Se thin films

• Published in: Materials chemistry and physics 2000-01, Vol.65 (3), p.298-305
• Main Authors: Sutrave, D S, Shahane, G S, Patil, V B, Deshmukh, L P
• Format: Article
• Language: English
• ISSN: 0254-0584

Chemo-mechanical synthesis of (Cd, Zn)Se thin films with a variable composition has been brought about with an objective to study the deposition history and the growth kinetics, structural changes and the optical properties and is presented in this paper. The effect of various process parameters (deposition time and temperature, concentration of the species, speed of the substrate rotation, pH, etc.) on the growth and quality of the films is studied experimentally. At the first insight, mechanistic interpretation of the reaction mechanism is given on the basis of the influence of the process parameters on the film growth, compositional, structural, microscopic and optical characteristics of Cd sub(1-x)Zn sub(x)Se thin films. The films are crystalline over the whole range studied with a predominant wurtzite structure for 0 less than or equal to x < 0.2 and a zinc blende structure (solid solution) for 0.7 < x less than or equal to 1. The film compositions in the middle of the range (0.2 less than or equal to x < 0.7) include both the cubic and the hexagonal structures. The crystal size determined from the XRD and SEM micrographs, is observed to decrease with increasing x (up to x identical with 0.5). The optical gap estimation showed a non-linear increase in the band gap with increasing Zn content in the film.