Title :
Turn-on characteristics of polycrystalline silicon TFT´s-impact of hydrogenation and channel length
Author :
Xu, Y.Z. ; Clough, F.J. ; Narayanan, E.M.S. ; Chen, Y. ; Milne, W.I.
Author_Institution :
Dept. of Electr. & Electron. Eng., De Montfort Univ., Leicester, UK
Abstract :
Experimental measurements and two-dimensional (2-D) numerical simulation have been used to investigate the impart of the polycrystalline silicon (poly-Si) density of states (DOS) and channel dimensions on the transient response of poly-Si thin-film transistors (TFTs). TFTs exposed to different hydrogenation times were used to investigate the effect of the poly-Si DOS. The experimental results show that TFT turn-on time increases with increasing channel length and decreases with increasing hydrogenation time. For the first time, transient simulations were carried out using "best fit" poly-Si DOS distributions which were extracted numerically from DC transfer characteristics. The resulting simulations show excellent agreement with the experimental data. Degradation in the transient characteristic is thereby correlated with an increase In the poly-Si DOS.
Keywords :
electronic density of states; elemental semiconductors; hydrogenation; semiconductor device measurement; semiconductor device models; silicon; thin film transistors; transient response; 2D numerical simulation; Si:H; best fit DOS distributions; channel dimensions; channel length; density of states; hydrogenation; hydrogenation times; polysilicon TFT; transfer characteristics; transient characteristic degradation; transient response; transient simulations; turn-on characteristics; Circuits; Data mining; Density measurement; Fabrication; Numerical simulation; Plasma temperature; Silicon; Thin film transistors; Transient response; Two dimensional displays;
Journal_Title :
Electron Device Letters, IEEE
