Mathematical model simulating the growth of compound semiconductor thin films via chemical bath deposition

Abstract

Chemical bath deposition is a thin film technique in which compound semiconductor thin films of typically 0.02-1 mu m thickness are deposited on the substrates immersed in dilute baths containing metal ions and a source of sulfide or selenide ions. Many I-VI, II-VI, IV-VI, and V-VI semiconductors are included in the list of materials deposited by this technique. However, a mathematical model describing the growth mechanism of these films in the context of batch production of large area thin films still remains to be established. The deposition process consists of a nucleation phase, growth phase, and a terminal phase, each of which depends on the concentration of the ions in the deposition bath, the temperature of the deposition, dissociation constants of the metal complex ions, etc. In this paper we propose a mathematical model which can qualitatively account for most of the features of the experimental growth curves of the chemically deposited semiconductor thin films. (C) 1999 Elsevier Science B.V. All rights reserved.