The Research On The Properties Of ZnO And Ti-doped ZnO Films Preparated By RF Magnetron Sputtering

A film is a two-dimensional material prepared by growing a small particle on the surface of a base sheet by a means,and is a transparent sheet having a thin and soft characteristic.Thin film materials can be prepared to achieve the effect of nano-level,in some applications has a pivotal role.The film material has a different effect from the powder material,such as its unique small-scale effect.So thin film research in the application of semiconductor devices has an unparalleled advantage,in addition it also improves the performance of optical devices has an important role in achieving more efficient optical design applications.Zinc oxide(Zn O)is the more fire of the semiconductor material,it belongs to the oxide series,the performance is relatively good.It has a wide band gap of 3.37 e V and a high exciton binding energy of 60 me V.Under normal circumstances hexagonal wurtzite structure is its basic structure.Zn O is widely used in UV light emitting diodes,transistors,dilute magnetic semiconductors,electroluminescent devices,thin film transistors,photovoltaic cells and other fields.In addition,zinc oxide film in the visible light band has high permeability,raw materials and has a large storage capacity,wide source,low cost,simple preparation and easy to doping,etc.,making zinc oxide has a very wide range of applications,zinc oxide film is Has received widespread attention.In this paper,Zn O thin films were fabricated by RF magnetron sputtering,and Ti-doped Zn O films were prepared by co-doping method.At different sputtering power,oxygen partial pressure,time,substrate temperature And the Zn O thin films were prepared on different substrates.The crystal structure,optical absorbency,transmittance and photoluminescence properties of the films were analyzed.The effects of different conditions on the microstructures were studied.Doped Zn O thin films and their effects on the properties of the Zn O thin films were discussed.Theconclusions are as follows:1.The effects of various process parameters on the properties of Zn O thin films were studied.(1)On the FTO substrate,the Zn O thin films are in the non-directional crystalline state,and the Zn O selective diffraction peak appears when the low power sputtering takes no time or at a higher power for a short time.Si(p / The sintered growth of c-substrate occurs at low power sputtering time,and the sapphire substrate is the most easily prepared Zn O thin film grown along the c-axis.Crystalline good substrate from good to bad is followed by sapphire substrate,Si substrate(p),Si substrate(n),FTO conductive glass.(2)all zinc oxide film samples in the 330 nm to 370 nm ultraviolet band,the UV has a strong absorption.All FTO substrate zinc oxide films have up to 90% of the visible light transmittance,especially in the case of an oxygen / oxygen ratio of 20:10,the transmittance reaches the highest state,while the pure argon,the corresponding film samples have the lowest Of the transmittance.In addition,we can find that in addition to the oxygen partial pressure of 20:20(sccm),when the oxygen partial pressure becomes larger,the absorption of Zn O thin film material made a clear "blue shift" phenomenon.While the UV emission peak also occurred a slight blue shift,the conclusion is consistent.In addition,the photoluminescence spectra of FTO substrate samples have three emission peaks at 395 nm,475nm and 495 nm,respectively.When the oxygen partial pressure is 20:10,the intrinsic luminescence intensity of the corresponding film is the strongest,Indicating that the oxygen partial pressure at 20:10,this case of Zn O film has a better quality of crystallization.(3)When the film samples are mostly in the lower coating power or lower coating time(not too low),the sample film growth is particularly slow,the film structure is stable,affected by the quantum size effect,photoluminescence characteristics more strongly The Such as 40 W of different sputtering power,20 min for simple sputtering time,3h for FTO substrate at low power for 3 hours,3h for sapphire substrate,and 3h for N-type Si substrate(of course,except P-type Si The end of the special,10 h when the best light).(4)On the sapphire substrate,the average size of the particle size becomes larger and the diffraction peak becomes stronger and the crystallization effect becomes better as the sputtering time increases after 3h and beyond.As can be seen,When the sputtering time is 2h to 6h,the diffraction peak is shifted to the high angle,which indicates that the interplanar spacing d(002)of the zinc oxide thin film decreases first,and when the sputtering time continues for 8h,the peak position is low Diffraction angle,indicating that the interplanar spacing has become larger.2.The influence of substrate type and heavy Ti-doped sputtering power ratio on the characterization of Ti-doped Zn O thin films was studied.In the aspect of substrate influence,the sapphire substrate samples have better crystallinity,showing better c-axis preferred growth,and smaller average grain size,but FTO and sapphire substrate samples are expressed in high power sputtering For the sapphire substrate samples,the sapphire substrate samples have better luminescent properties,and the sapphire substrate samples have less intrinsic intensity than the intrinsic luminescence peak intensity.Therefore,the luminescent properties of sapphire substrate samples are less affected by defects.With the increase of the Ti-sputtering power,the Ti-doping amount will increase greatly.Although the Zn O samples are also grown along the c-axis,the diffraction peak intensity Have a lower trend.However,the width of the Ti-doped Zn O thin films increases with the increase of the average grain size.In addition to 160: 40,the UV absorption intensity of the Ti-doped Zn O thin films is enhanced.,160: 40 sample intrinsic emission peak is relatively pure single,better luminosity.