Title :
Characteristics of offset-structure polycrystalline-silicon thin-film transistors
Author :
Tanaka, Keiji ; Arai, Hitoshi ; Kohda, Shigeto
Author_Institution :
Electr. Commun. Labs., NTT Corp., Tokyo, Japan
Abstract :
In order to reduce anomalous leakage current from n-channel polycrystalline-silicon thin-film transistors (poly-Si TFTs), an offset structure that has an n/sup -/ region between channel and n/sup +/ source-drain electrodes has been proposed. Drain-current measurements of the poly-Si TFT prove that the offset structure is effective in reducing the anomalous leakage current, and that the optimization of the offset length and the doping concentration in the offset region enlarge the ON/OFF current ratio. Implantation of 5*10/sup 13/ cm/sup -2/ phosphorus ions in the offset region makes the ON/OFF current ratio more than one order of magnitude larger than that of conventional structure TFTs.<>
Keywords :
elemental semiconductors; ion implantation; leakage currents; silicon; thin film transistors; Si; Si:P; anomalous leakage current; doping concentration; drain current; ion implantation; n/sup +/ source-drain electrodes; n/sup -/ region; offset length; offset structure; on off current ratio; polysilicon TFT; Active matrix technology; Current measurement; Doping; Electrodes; Electron mobility; Leakage current; Length measurement; Silicon compounds; Thin film transistors; Voltage;
Journal_Title :
Electron Device Letters, IEEE
