The bottom-gate structure ZnO based thin film transistors （ZnO-TFTs） using Bi1.5Zn1.0Nb1.507 （BZN） thin films as gate insulator were fabricated on Pt/SiO2/Si substrate by radio frequency magnetic sputtering. We in...The bottom-gate structure ZnO based thin film transistors （ZnO-TFTs） using Bi1.5Zn1.0Nb1.507 （BZN） thin films as gate insulator were fabricated on Pt/SiO2/Si substrate by radio frequency magnetic sputtering. We investigated the effect of annealing temperature at 300, 400, and 500℃ on the performance of BZN thin films and ZnO-TFTs. XRD measurement confirmed that BZN thin films were amorphous in nature. BZN thin films annealed at 400℃ obtain the high capacitance density of 249 nF/cm2, high dielectric constant of 71, and low leakage current density of 10^-7 A/cm2 ordoff current ratio and field effect mobility of ZnO-TFTs annealed at 400℃ are approximately one order of magnitude and two times, respectively higher than that of ZnO-TFTs annealed at 300℃. When the annealing temperature is 400℃, the electrical performance of ZnO-TFTs is enhanced remarkably. Devices obtain a low sub-threshold swing of 470 mV/dec and surface states density of 3.21×10^12cm^-2.展开更多
Top-contact thin film transistors（TFTs） using radio frequency（RP） magnetron sputtering zinc oxide （ZnO） and silicon dioxide（SiO;） films as the active channel layer and gate insulator layer,respectively,were fa...Top-contact thin film transistors（TFTs） using radio frequency（RP） magnetron sputtering zinc oxide （ZnO） and silicon dioxide（SiO;） films as the active channel layer and gate insulator layer,respectively,were fabricated.The performances of ZnO TFTs with different ZnO film deposition temperatures（room temperature, 100℃and 200℃） were investigated.Compared with the transistor with room-temperature deposited ZnO films, the mobility of the device fabricated at 200℃is improved by 94%and the threshold voltage shift is reduced from 18 to 3 V（after 1 h positive gate voltage stress）.Experimental results indicate that substrate temperature plays an important role in enhancing the field effect mobility,sharping the subthreshold swing and improving the bias stability of the devices.Atomic force microscopy was used to investigate the ZnO film properties.The reasons for the device performance improvement are discussed.展开更多
基金Project supported by the National Natural Science Foundation of China(Nos.51332003,51202184)the International Science&Technology Cooperation Program of China(Nos.2010DFB13640,2011DFA51880)the "111 Project" of China(No.B14040)
文摘The bottom-gate structure ZnO based thin film transistors （ZnO-TFTs） using Bi1.5Zn1.0Nb1.507 （BZN） thin films as gate insulator were fabricated on Pt/SiO2/Si substrate by radio frequency magnetic sputtering. We investigated the effect of annealing temperature at 300, 400, and 500℃ on the performance of BZN thin films and ZnO-TFTs. XRD measurement confirmed that BZN thin films were amorphous in nature. BZN thin films annealed at 400℃ obtain the high capacitance density of 249 nF/cm2, high dielectric constant of 71, and low leakage current density of 10^-7 A/cm2 ordoff current ratio and field effect mobility of ZnO-TFTs annealed at 400℃ are approximately one order of magnitude and two times, respectively higher than that of ZnO-TFTs annealed at 300℃. When the annealing temperature is 400℃, the electrical performance of ZnO-TFTs is enhanced remarkably. Devices obtain a low sub-threshold swing of 470 mV/dec and surface states density of 3.21×10^12cm^-2.
基金Project supported by the National High Technology Research and Development Program of China(No2008AA3A336)the Shanghai Municipal Committee of Science and Technology,China(No09530708600)
文摘Top-contact thin film transistors（TFTs） using radio frequency（RP） magnetron sputtering zinc oxide （ZnO） and silicon dioxide（SiO;） films as the active channel layer and gate insulator layer,respectively,were fabricated.The performances of ZnO TFTs with different ZnO film deposition temperatures（room temperature, 100℃and 200℃） were investigated.Compared with the transistor with room-temperature deposited ZnO films, the mobility of the device fabricated at 200℃is improved by 94%and the threshold voltage shift is reduced from 18 to 3 V（after 1 h positive gate voltage stress）.Experimental results indicate that substrate temperature plays an important role in enhancing the field effect mobility,sharping the subthreshold swing and improving the bias stability of the devices.Atomic force microscopy was used to investigate the ZnO film properties.The reasons for the device performance improvement are discussed.
