Electronic transport and optical properties of nano-structured Pt-doped CdO films: evaluate the effect of treatment in hydrogen gas

Abstract

Cadmium oxide (CdO) has various applications related to its natural optoelectronic properties as an oxide, which belongs to group of transparent conducting oxides. However, those properties could be controlled to a desired choice by doping method. For developing the application in the field of optoelectronics, the conduction parameters (conductivity, carrier mobility, and carrier concentration) together with the transparency in the NIR should be improved. Therefore, it is important to seek ways to realise those improvements. Doping method is the way that used to attain that aim. In the present work, CdO thin films doped with different amounts of platinum (Pt) ions were deposited on glass and silicon substrates by the method of physical vapour deposition. The deposited films were characterized by X-ray fluorescence, X-ray diffraction, optical absorption spectroscopy, and electrical measurements. A variety of results was obtained in the present work; the optimum improvement in the electrical properties was found with CdO film doped with 0.13 wt% Pt. A combination of low resistivity (1.74 × 10−4 Ω cm), high carrier concentration (1.02 × 1021 cm−3) and relatively high mobility (35.4 cm2/V s) were obtained under hydrogenation.