We have optimised and deposited epitaxial indium zinc oxide (epi-IZO) (In2Zn2O5) thin films on <100> oriented Si, GaAs. and InP by laser-molecular beam epitaxy (L-MBE) technique, i.e., pulsed laser deposition (PLD). Optimised growth conditions have been obtained for the deposition of high quality epi-IZO thin films. To our knowledge, this is the first time that the PLD deposited indium zinc oxide thin films on semiconductor wafers have been applied to semiconductor-insulator-semiconductor (SIS) iso- and hetero-type junction solar cell structures as wide band gap transparent conducting front electrode-window layers. We have carried out X-ray diffraction (XRD) and energy dispersive chemical analysis (EDAX) to determine the Structural and compositional properties of as-grown thin films. The crystalline quality of the obtained thin films is similar to that of the bulk single crystals. Increasing the deposition temperature leads the thin films to fine nano-structure nature. In the present work, the effects of various substrate temperatures, substrates and heavy indium oxide doping on indium zinc oxide thin film growth, structural and compositional properties were analysed.. As well as our main aim, the feasibility of developing high quality transparent conducting oxide (TCO) thin films for opto-electronic devices was also studied simultaneously. Our novel achievement in this work is without any buffer layers, we have obtained good epitaxial lattice matching between the highly oriented IZO functional layers and the substrate materials suitable for III-V based high-speed opto-electronic and micro-electronic devices. (C) 2003 Elsevier B.V. All rights reserved.