Research On Technics Of ZnO-based Diluted Magnetic Semiconductors By Radio Frequency Magnetron Sputtering

With the development of modern information technology, dilute magnetic semiconductors attract much attition because of unique properties.It has two sets of freedom degrees—spin and charge in the same matrix, along with characteristics of magnetic and semiconductor materials, shows a very broad application prospects in electronics and photonics spin fields , such as spin valves, spin diodes, stable memory, logic devices and high-speed optical switches and so on.So dilute magnetic semiconductor materials is a topic worthy of deeply study both in theory and in application.This paper's main work are as follow:1, The concept of diluted magnetic semiconductor, research progress and application fields are introduced.2, In order to get high quality Cr-doped ZnO films, first of all,optimize the parameters,the effect of deposition power, substrate temperature, the ratio of argon oxygen, working pressure on deposition rate and growth of ZnO thin film has been made.The best parameters of ZnO thin film on polished silicon are as follow: the substrate temperature 400℃, the range from 6 cm, the ratio of argon oxygen ,9:4, sputtering power 170W, work pressure,1.5 pa.In this situation,ZnO thin film has good crystallizationand shows high C-axis orientation.3, Cr doped ZnO thin films prepared by Magnetron sputtering.Doping concentration can gain by controling the time.A group of samples need heat treatment.Using of X-ray and scanning electron microscopy, physical properties measuring instrument, the parameters can be optimized continuously. The best option of Cr doped ZnO thin film can get.Through testing ,the best parameters are as follows: work pressure,1.5 pa , substrate temperature ,400℃, the ratio of argon oxygen ,9:4, sputtering power ,170 W, DC voltage, 320V, DC current, 340mA. By annealing, the sample Zn_1-xCr_xO films all showed ferromagnetic, and they have remarkable hysteresis phenomenon . When Cr doped ZnO thin film's concentration is 2.10%, ferromagnetic and crystallization of thin film are better.