Effect of Cadmium Doping Zinc Oxide (Cd: Zno) Films on Optical and Sensitivity of Gas (NH3) Properties Prepared by Spray Pyrolysis Technique

Authors

  • Taha Yaseen Rashid, Waleed S. Abdul wahab, Asrar A. Saeed, Asaad.M.Abbas

Abstract

Thin films of cadmium doped zinc oxide (Cd : ZnO) with various cadmium concentrations
(2,4,6,8,10%).have been synthesis by the spray pyrolysis Technique on glass substrates at
450 ?C. The optical properties and sensitivity of The films prepared were studied for
increased cadmium concentration.The x-ray diffraction analysis show that the filmsare
polycrystalline in having a hexagonal wurtzite type crystal structure with a distinguish grain
orientation in the (0 0 2) direction. With an increase Cd doping, Atomic force microscopy
(AFM) measurements revealed that the increase surface Roughness of the films with a
decrease in the grain size due to increase of Cd concentration .optical measurements showed
that the band gap decreases from 3.5 eV to 2.6 eV At a doping (10%) ratio. The films are
highly transparent in the visible region and the absorption edge showed a red shift. Also, the
sensitivity test for aluminum gas shows an increase in the sensitivity rate with an increase in
the cadmium concentration.

Published

2020-10-14

Issue

Section

Articles