Chen Zhuo, Lan Linfeng, Peng Junbiao
State Key Laboratory of Luminescent Materials and Devices, South China University of Technology Guangzhou 510640 China
RSC Adv. 2019 Aug 28;9(46):27117-27124. doi: 10.1039/c9ra03574e. eCollection 2019 Aug 23.
Low-temperature giant-dielectric-constant thin films (InNbTiO) fabricated with simple radio frequency (RF) sputtering on glass substrates are employed as the gate dielectrics for thin-film transistors (TFTs) for the first time. The 380 nm-thick InNbTiO film exhibited a quasi-static capacitance of as high as 36 156 nF cm with a quasi-static permittivity of 15 525 (and 7607 nF cm at 1 kHz). Indium zinc oxide (IZO) TFTs with InNbTiO gate dielectrics exhibited high output current at low operation voltage and little hysteresis in the transfer curves between forward and reverse sweeps. The subthreshold swing (SS) of the IZO TFTs is 0.068 V dec, very close to the lowest limit of the SS of the field-effect transistors (0.06 V dec). The results also proves that the lowest limit of the SS (0.06 V dec) cannot be broken no matter how high the gate dielectric capacitance is (except for negative capacitors). The TFTs demonstrate the potential for the applications in low-power circuits or flat-panel displays.
首次将通过简单射频（RF）溅射在玻璃基板上制备的低温巨介电常数薄膜（InNbTiO）用作薄膜晶体管（TFT）的栅极电介质。厚度为380 nm的InNbTiO薄膜表现出高达36156 nF/cm²的准静态电容，准静态介电常数为15525（在1 kHz时为7607 nF/cm²）。具有InNbTiO栅极电介质的铟锌氧化物（IZO）TFT在低工作电压下表现出高输出电流，并且在正向和反向扫描之间的转移曲线中滞后很小。IZO TFT的亚阈值摆幅（SS）为0.068 V/dec，非常接近场效应晶体管SS的最低极限（0.06 V/dec）。结果还证明，无论栅极电介质电容有多高（负电容除外），SS的最低极限（0.06 V/dec）都无法突破。这些TFT展示了在低功耗电路或平板显示器中的应用潜力。
