Transparent zinc oxide thin film transistors (ZnO-TFTs) with bottom-gate and top-gate structures were constructed on 50mm silica glass substrates. The ZnO films were deposited by RF magnetron sputtering and SiO2 fil...Transparent zinc oxide thin film transistors (ZnO-TFTs) with bottom-gate and top-gate structures were constructed on 50mm silica glass substrates. The ZnO films were deposited by RF magnetron sputtering and SiO2 films served as the gate insulator layer. We found that the ZnO-TFTs with bottom-gate structure have better electrical performance than those with top-gate structure. The bottom-gate ZnO-TFTs operate as an n-channel enhancement mode, which have clear pinch off and saturation characteristics. The field effect mobility, threshold voltage, and the current on/off ratio were determined to be 18.4cm^2/(V ·s), - 0. 5V and 10^4 , respectively. Meanwhile, the top-gate ZnO-TFTs exhibit n-chan- nel depletion mode operation and no saturation characteristics were detected. The electrical difference of the devices may be due to the different character of the interface between the channel and insulator layers. The two transistors types have high transparency in the visible light region.展开更多
The hot deformation behavior of homogenized zinc alloy was investigated through uniaxial compression test on a Gleeble-1500 thermal-mechanical simulator within a temperature range of 230-380°C and a strain rate r...The hot deformation behavior of homogenized zinc alloy was investigated through uniaxial compression test on a Gleeble-1500 thermal-mechanical simulator within a temperature range of 230-380°C and a strain rate range of 0.01-10 s -1 ,the corresponding flow curves and their characters were determined and analyzed,and microstructures were studied by optical,SEM and TEM microscopy.The results indicated that the microstructure evolution of zinc alloy during hot deformation involves the spheroidization of the phase of TiZn15,coarsening of the precipitated phase and dynamic recrystallization(DRX)of the phase of matrix,leading to the formation of the polyphase(η+ε+TiZn15)structure.The spheroidization of the phase of TiZn15 during hot deformation was beneficial to the particle nucleation stimulated and then promoted to DRX of matrix.The dynamic recrystallization grain size of the matrix phase decreased firstly and then increased with elevating the temperature,and the degree of DRX became more complete when the strain rate and strain became larger.Hot deformation accelerated the diffusion of Cu atom,which resulted in the coarsening of the precipitated phase.Thus,the microstructure was refined owing to the pinning effect of the precipitated phase.展开更多
文摘Transparent zinc oxide thin film transistors (ZnO-TFTs) with bottom-gate and top-gate structures were constructed on 50mm silica glass substrates. The ZnO films were deposited by RF magnetron sputtering and SiO2 films served as the gate insulator layer. We found that the ZnO-TFTs with bottom-gate structure have better electrical performance than those with top-gate structure. The bottom-gate ZnO-TFTs operate as an n-channel enhancement mode, which have clear pinch off and saturation characteristics. The field effect mobility, threshold voltage, and the current on/off ratio were determined to be 18.4cm^2/(V ·s), - 0. 5V and 10^4 , respectively. Meanwhile, the top-gate ZnO-TFTs exhibit n-chan- nel depletion mode operation and no saturation characteristics were detected. The electrical difference of the devices may be due to the different character of the interface between the channel and insulator layers. The two transistors types have high transparency in the visible light region.
基金Project(2009BAE71B03)supported by the National Key Technology Support Program of China During the 11th Five-year Plan Period
文摘The hot deformation behavior of homogenized zinc alloy was investigated through uniaxial compression test on a Gleeble-1500 thermal-mechanical simulator within a temperature range of 230-380°C and a strain rate range of 0.01-10 s -1 ,the corresponding flow curves and their characters were determined and analyzed,and microstructures were studied by optical,SEM and TEM microscopy.The results indicated that the microstructure evolution of zinc alloy during hot deformation involves the spheroidization of the phase of TiZn15,coarsening of the precipitated phase and dynamic recrystallization(DRX)of the phase of matrix,leading to the formation of the polyphase(η+ε+TiZn15)structure.The spheroidization of the phase of TiZn15 during hot deformation was beneficial to the particle nucleation stimulated and then promoted to DRX of matrix.The dynamic recrystallization grain size of the matrix phase decreased firstly and then increased with elevating the temperature,and the degree of DRX became more complete when the strain rate and strain became larger.Hot deformation accelerated the diffusion of Cu atom,which resulted in the coarsening of the precipitated phase.Thus,the microstructure was refined owing to the pinning effect of the precipitated phase.