The Study On The Effects Of PEG And Co-doping On The Structure And Property Of ZnCoO Thin Films

ZnO is a semiconductor ofâ…¡-â…¥race with a wide direct band gap and a wurtzite structure. It has comparatively large exciton binding energy (60meV) and is capability of emiting ultraviolet at the room temperature. The high quality ZnO thin film is one of most potential membranous materials at present. Zinc oxide with a high stability and a direct band gap of 3.37eV has greatly attracted attention because of its high potential for application as short wavelength optical devices.There are many defects in ZnO, For example intrinsic defects including oxygen vacancies and zinc interstitials,donor-acceptor transition, recombination at Vo centers,zinc vacancy and surface defects.doping will bring about various defects including lattice distortion dislocation, Stacking fault.those defects will have decisively influence on the property of ZnO Nanostructures which caused n-type ZnO films. Hower,one important problem should be overcome before ZnO could potentially make inroads into the words of optoelectronics devices:the growth of p-type-conductivity ZnO crystal.those defects make pure ZnO Nanoparticles having ferromagnetic behavior.moreover the renewed interest is reports of p-type conduction and ferromagnetic behavior when doped with transition metals,both of which remain controversial. The main obstracle to the development of ZnO has been the lack of reproducible and low -resistivity p-type ZnO. It has been found that the addition of Zn interstitials, which affects both the number of neutral and ionized donors, leads to an increase in the ferromagnetism [11], and a recent study of Al-doped ZnCoO has reported a variation of magnetization with Al content rather than carrier density [12]. Recently reports suggest that the bandage of ZnO will vary if Co, Al or Ca ions doped into ZnO nanrods. This will be very beneficial to the modulation of optical parameter of optoelectric devices and the production of magnetic.Chemical vapor deposition (CVD),metal organic chemical vapordeposition (MOCVD),pulser laser deposition (PLD)and molecular beam epitaxy(MBE)method have been reported for the successful preparation of ZnO nanorods with a high aspect ratio which need a high temperature.While Hydrothermal synthesis of nanorods relatively more simple and low cost. Hydrothermal preparation of single crystal doped ZnO nanorod arrays are in situ doping method, comparing to ion implantation and metal vapor doping method,which have less structural defects. So it is very important for studying doped mechanism and properties of stability. For Hydrothermal method, Doping is a challenge.It is the issue of the examined for how to dop and the influence on Shape, structure and properties because of doping.Reports suggest that co-doping is a feasible way to obtain p-type ZnO ferromagnetic and improve the performance. Only to make certain the mechanistic,we can have a good control of the distribution of doping atoms, and thus control the performance.In the present paper,we prepar the ZnO films by sol-gel method on glass which has a low price, and then produce Well-aligned ZnO nanorod arrays with doping via hydrothermal method.The influence of Co doptant to ZnO nanorods for the instructure, morphology and luminence have been studied systematically. Co-doping making UV emission peak shifts 12 nm. I analysis the relation of excitation dependence of PL spectra for the NBE emission and the reason of bule shifs.The influence of PEG to ZnO nanorods for the instrucure have been studied systematically.From the paper we can see that adequte PEG can contribute ZnCoO nanorods array to good crystallographic orientation.The effect of Ga content on structure and magnetic property of film via Sol-Gel method was studied systematically.And the mechanism of the magnetism on the films was aso analyzed.The effect of Al content on structure, luminescence and magnetic property of the single-crystal ZnCoO nanorods arrays via hydrothermal method was studied systematically. Scanning microscope, XRD, Raman spectroscopy and dynamic sample magnetometer (VSM) were used to analyze the structure, light-emitting mechanism and the mechanism of magnetic respectively.