In this article, an organic thin-film field-effect transistor （OTFFET） with top-gate and bottom-contact geometry based on pentacene as the active layer is fabricated. The experimental data of the I-V are obtained fr...In this article, an organic thin-film field-effect transistor （OTFFET） with top-gate and bottom-contact geometry based on pentacene as the active layer is fabricated. The experimental data of the I-V are obtained from the OTFFET device. The alternating-current （AC） resistance value of the OTFFET device is calculated using the derivation method from the experimental data, and the AC resistance trend curves of the OTFFET device are obtained with the region fitting method. We analyse the characteristics of the OTFFET device with an AC resistance trend curve. To discover whether it has a high resistance, it is proposed to judge the region of the source/drain voltage （VDs） less than the transition voltage, thereby determining whether the contact between the metal electrode and the organic semiconductor layer of the OTFFET device is Ohmic or non-Ohmic. The theoretical analysis shows that the field-effect mobility and the AC resistance are in reverse proportion. Therefore, we point out that reducing AC resistance is necessary if field-effect mobility is to be improved.展开更多
A physical drain current model of polysilicon thin-film transistors based on the charge-sheet model, the density of trap states and surface potential is proposed.The model uses non-iterative calculations,which are sin...A physical drain current model of polysilicon thin-film transistors based on the charge-sheet model, the density of trap states and surface potential is proposed.The model uses non-iterative calculations,which are single-piece and valid in all operation regions above flat-band voltage.The distribution of the trap states,including both Gaussian deep-level states and exponential band-tail states,is also taken into account,and parameter extraction of trap state distribution is developed by the optoelectronic modulation spectroscopy measurement method. Comparisons with the available experimental data are accomplished,and good agreements are obtained.展开更多
Accounting for the deep Gaussian and tail exponential distribution of the density of states, a physical approximation for potentials of amorphous silicon thin-film transistors using a symmetric dual gate （sDG a-Si：H...Accounting for the deep Gaussian and tail exponential distribution of the density of states, a physical approximation for potentials of amorphous silicon thin-film transistors using a symmetric dual gate （sDG a-Si：H TFT） has been presented. The proposed scheme provides a complete solution of the potentials at the surface and center of the layer without solving any transcendental equations. A channel current model incorporating features of gate voltage-dependent mobility and coupling factor is derived. We show the parameters required for accurately describing the current-voltage （l-V） characteristics of DG a-Si：H TFT and just how sensitively these parameters affect TFT current. Particularly, the parameters＇ dependence on the I-V characteristics with respect to the density of deep state and channel thickness has been investigated in detail. The resulting scheme and model are successively verified through comparison with numerical simulations as well as the available experimental data.展开更多
基金Project supported by the National Grand Fundamental Research 973 Program of China (Grant No. 2010CB327704)the National Natural Science Foundation of China (Grant Nos. 10974013 and 60978060)+3 种基金the Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20090009110027)the Natural Science Foundation of Beijing,China (Grant No. 1102028)the National Natural Science Foundation for Distinguished Young Scholars (Grant No. 60825407)Beijing Municipal Science and Technology Commission (Grant No. Z090803044009001)
文摘In this article, an organic thin-film field-effect transistor （OTFFET） with top-gate and bottom-contact geometry based on pentacene as the active layer is fabricated. The experimental data of the I-V are obtained from the OTFFET device. The alternating-current （AC） resistance value of the OTFFET device is calculated using the derivation method from the experimental data, and the AC resistance trend curves of the OTFFET device are obtained with the region fitting method. We analyse the characteristics of the OTFFET device with an AC resistance trend curve. To discover whether it has a high resistance, it is proposed to judge the region of the source/drain voltage （VDs） less than the transition voltage, thereby determining whether the contact between the metal electrode and the organic semiconductor layer of the OTFFET device is Ohmic or non-Ohmic. The theoretical analysis shows that the field-effect mobility and the AC resistance are in reverse proportion. Therefore, we point out that reducing AC resistance is necessary if field-effect mobility is to be improved.
基金Project supported by the Key Project of Chinese Ministry of Education(No.211206)the Fundamental Research Funds for the Central Universities (No.21611422)the Foundation for Distinguished Young Talents in Higher Education of Guangdong,China(No.LYM10032)
文摘A physical drain current model of polysilicon thin-film transistors based on the charge-sheet model, the density of trap states and surface potential is proposed.The model uses non-iterative calculations,which are single-piece and valid in all operation regions above flat-band voltage.The distribution of the trap states,including both Gaussian deep-level states and exponential band-tail states,is also taken into account,and parameter extraction of trap state distribution is developed by the optoelectronic modulation spectroscopy measurement method. Comparisons with the available experimental data are accomplished,and good agreements are obtained.
基金supported by the National Natural Science Foundation of China(No.61274085)the Cadence Design System,Inc
文摘Accounting for the deep Gaussian and tail exponential distribution of the density of states, a physical approximation for potentials of amorphous silicon thin-film transistors using a symmetric dual gate （sDG a-Si：H TFT） has been presented. The proposed scheme provides a complete solution of the potentials at the surface and center of the layer without solving any transcendental equations. A channel current model incorporating features of gate voltage-dependent mobility and coupling factor is derived. We show the parameters required for accurately describing the current-voltage （l-V） characteristics of DG a-Si：H TFT and just how sensitively these parameters affect TFT current. Particularly, the parameters＇ dependence on the I-V characteristics with respect to the density of deep state and channel thickness has been investigated in detail. The resulting scheme and model are successively verified through comparison with numerical simulations as well as the available experimental data.
