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We have investigated the linear and nonlinear optical properties of high quality cerium-doped zinc oxide films (ZnO:Ce). The layers were grown by the reactive chemical pulverization spray pyrolysis technique using zinc and cerium chlorides as precursors at temperature up to 450 o C. The influence of Ce concentration on the structural, linear and nonlinear optical properties of ZnO thin films is presented. The films were characterized by X-ray diffraction, scanning electron microscope and photoluminescence measurements. The X-ray diffraction analysis indicates that all films are polycrystalline in nature and clearly shows the appropriate incorporation of the Ce atoms in the ZnO films. The third order nonlinear optical properties, which are the main subject of this investigation, were studied. For this propose, the third harmonic degeneration (THG) technique has been employed. A laser source has been used for the fundamental beam at 1064 nm so that the generated third harmonic signal is made at 355 nm.

They are steel need for low cost and high performance in optoelectronic devices leads to the development of more efficient transparent conductive oxide thin films for many applications in optic and optoelectronics: up-conversion frequency (SHG, THG), gas sensors, optical position sensors, acoustic wave transducers, liquidcrystal displays etc From almost all the transparent materials studied during recent years, zinc oxide (ZnO) has emerged as one of the most promising materials due to its optical and electrical properties, its high chemical and mechanical stability and, owing to its abundance in nature, it is a lower cost material compared with the most currently used materials ITO and SnO2. There has been great interest in the oxide semiconductor ZnO and its ternary alloys in recent years for its potential application in UV band applications. ZnO is a direct band-gap II-VI semiconductor material having an energy gap of 3.3 eV at room temperature with high exciton binding energy (60 meV). Until now, ZnO thin films have been prepared by a number of techniques such as spray pyrolysis, RF magnetron sputtering, pulsed laser deposition, laser molecular beam epitaxy, sol-gel. However, undoped ZnO thin films are not stable, especially at high temperatures. Doping the zinc oxide can increase the stability reduce this disadvantage. Additionally doping can leads to an increase of the nonlinear optical properties of the ZnO thin films.In this paper, cerium-doped zinc oxide films (ZnO:Ce) were deposited by reactive chemical pulverisation spray pyrolysis technique using zinc and cerium chloraids as precursors at temperatures up to 500 °C. The effect of Ce concentration on the structural, electrical and optical properties of ZnO thin films were carefully investigated. These films were studied using Four Probe Method, X-ray diffraction and Photoluminescence measurement. The X-ray diffraction analysis indicates that all films are polycrystalline in nature and clearly shows the appropriate incorporation of Ce atoms in the ZnO films. The chemical composition of the films as determined by energy dispersive spectroscopy is also reported. The ZnO layers display three major PL peaks: an UV near-band edge emission peak at 378 nm, a green emission around 510 nm, and a red emission around 650 nm. The green emission and red emission are probably associated with the oxygen vacancies and interstitial Zn ions in the ZnO lattice. The influences of Ce concentration on the nonlinear optical properties using THG technique will be presented.