This paper presents an optical sensor structure for microposition detection application using transparent electrodes of indium doped ZnO (IZO). The optical microsensor consists of two linear arrays of metal semiconductor - metal (MSM) silicon photodetectors with IZO transparent electrodes integrated with a polymer optical waveguide. IZO layers with a thickness of 460-580 nm have been deposited by dc magnetron sputtering technique on silicon epitaxial wafers of 30-50 Omega cm resistivity and a thickness of 23 mu m. Due to their high optical transmittance (>90%) over the 0.4-0.9 mu m spectral range, these layers contributed to an increased responsivity of the MSM photodiode structure of about 0.34 A/W, thus improving the optical position microsensor sensitivity. (C) 2009 Elsevier B.V. All rights reserved.