Fabrication Process of an Embedded System Based Spin Coating Machine and the Growth of Magnesium Doped Zinc Oxide Thin Films

Embedded system based spin coating machine is developed for the growth of thin films. The spin coating machine is fully controlled by PIC microcontroller (PIC16f877A), which could be driven by driver circuit to drive a spinning motor and Magnesium doped Zinc Oxide thin films are deposited using this machine. XRD results indicated that the films are hexagonal wurtzite structure with preferred orientation and the crystallite size increase with increasing doping concentration of Mg. The surface morphology investigation shows grains are shapes in irregular and doping concentrations are not influence the surface morphology. From TEM image observed particle sizes ranging between 23 nm and 28 nm with an average value of ~25.8 nm. The maximum visible average transmittance was observed to be 96% for optimum Mg doping concentration of 10 wt %. The investigated DC electrical conductivity of Mg doped ZnO thin films shows the enhanced electrical conductivity than pure ZnO and the AC conductivity is decreased with increasing Mg doping concentrations from 5 to 10 wt%.