Reseach On Optical And Electrical Properties And Residual Stress Of Al Doped GZO Thin Films

In order to do the researches on Al and Ga doped ZnO thin films(AGZO thin film) prepared in different experiment parameters, this experiment prepared several AGZO film samples on glass substrates by RF magnetron co-sputtering method using both Al target and GZO target, in different Al target sputtering time, different Al target sputtering power and different GZO sputtering power, and I do the annealing procedure on some AGZO samples. And we used some measurements such as XRD, SEM, spectrometer and hall measurement, also we used some related theories and formulas to measure several performances of AGZO film samples including structure, optical and electrical performance and residual stress.1. When I change the Al target sputtering time from 1min to 9min:(1) the AGZO thin films all have preferred orientation in(002) direction. Based on both calculated average grain size and SEM photo of the sample surface, the crystallinity of the samples firstly increased then droped.(2) The transmittance in Visible light band first went down and then went higher.(3) The resistivity of the AGZO samples firstly decreased as the crystallinity increased, then it increased.(4) As the sputtering time of Al target went longer, the residual stress raised. By changing the sputtering time of Al target, the highest transmittance of the five AGZO samples was 91.41% and the lowest resistivity was 11.46×10-3Ωcm.2. When changing the sputtering power of the Al target, and set the power as 30 W to 70W:(1)the prepared AGZO film samples also have preferred orientation in(002) direction, And the crystallinity of the samples went up earlier and then declined;(2)the average transmittance of visible light band is the reverse trend of the crystallinity;(3)but the resistivity of the samples is in the same tendency of the crystallinity as sputtering power of Al target went higher;(4)and the residual stress went up firstly, then went down but finally slightly went up again. Within these five AGZO samples, the best transmittance, residual stress and resistivity were 91.49%, 1.77 GPa and 8.93×10-3 Ωcm, respectively.3. When I set the sputtering power of GZO target as 75 W, 100 W, 125 W, 150 W, 175W:(1)the prepared AGZO thin film samples only had(002) diffraction peak, and the average grain size got bigger as the sputtering power increased, which could mean the crystallinity of the samples were better gradually,(2)the average transmittance didn’t have a certain tendency, but they were all exceeded 88%.(3)As the sputtering power of GZO target went higher, the resistivity went down;(4)and the residual stress of the sample prepared with the GZO target sputtering power of 150 W was much high than the other four samples, the other fous samples had similar residual stress. And when the sputtering power of GZO target was 175 W, the biggest average grain size was 29.04 nm, the lowest resistivity was 6.36×10-3Ωcm.4. After the annealing process in vacuum, the AGZO thin film samples didn’t change their(002) direction of preferred orientation, but the average grain size became large, which could mean the crystallinity improved. As the improvement of the crystal structure of the AGZO films, the residual stress decreased and the mobility of the carrier increased. But we didn’t get a definite changing trend of resistivity. The average of the transmittance in visible light band declined after annealing.