Optical, Electrical, and Morphological Effects of Yttrium Doping of Cadmium Oxide Thin Films Grown by Ultrasonic Spray Pyrolysis

• Published in: Journal of electronic materials 2017-04, Vol.46 (4), p.2090-2096
• Main Authors: Tombak, Ahmet, Baturay, Silan, Kilicoglu, Tahsin, Ocak, Yusuf Selim
• Format: Article
• Language: English
• Subjects: Characterization and Evaluation of Materials; Chemistry and Materials Science; Electric properties; Electronics and Microelectronics; Instrumentation; Materials Science; Metal oxides; Optical and Electronic Materials; Optical properties; Solid State Physics; Thin films
• ISSN: 0361-5235; 1543-186X
• DOI: 10.1007/s11664-016-5134-9

CdO films doped with Y concentrations of 0%, 1%, 2%, and 3% were deposited onto soda lime glass using ultrasonic spray pyrolysis. The effect of the doping level on the structural, morphological, optical, and electrical properties of the films was characterized. X-ray diffraction analysis was used to establish that all of the samples were polycrystalline and to determine the structural parameters, i.e., lattice spacing ( d ), phases and associated ( hkl ) planes, grain size ( D ), and dislocation density ( δ ). The films possessed high conductivity and carrier concentration, showing n -type semiconducting behavior. The films were almost transparent over the range from 600 nm to 1100 nm. The energy bandgap was 2.43 eV, 2.53 eV, 2.68 eV, and 2.70 eV for Y doping of 0%, 1%, 2%, and 3%, respectively. The refractive index and extinction coefficient of the films over the range from 700 nm to 1100 nm were determined by spectroscopic ellipsometry. Atomic force microscopy revealed the effect of Y doping on the surface morphology of the CdO films.