Title :
Simulation of influence of density of states in a-Si:H on electrical performance of a-Si:H thin-film transistors
Author :
Chen, Chun-ying ; Kanicki, Jerzy
Author_Institution :
Dept. of Electr. Eng. & Comput. Sci., Michigan Univ., Ann Arbor, MI, USA
Abstract :
A two-dimensional analysis of the density of states in hydrogenated amorphous silicon (a-Si:H) thin film transistors (TFT) is simulated by Semicad Device program. The model of the density of states in a-Si:H consists of conduction-band and valence-band-tail states, and deep-gap states. We found that mobility is sensitive to the conduction-band-tail states and threshold voltage is mainly determined by the combination of the deep-gap states, interface states and fixed charges, which are localized at or near the gate insulator/a-Si:H interface. We have also analyzed the physical origin of the nonlinearity of current-voltage characteristic of a-Si:H TFT. The influence of top and bottom gate insulator/a-Si:H interfaces on TFT performance are compared
Keywords :
amorphous semiconductors; band structure; digital simulation; elemental semiconductors; interface states; physics computing; silicon; simulation; thin film transistors; Semicad Device; Si:H; a-Si:H; a-Si:H TFT; a-Si:H thin-film transistors; conduction-band; current-voltage characteristic; deep-gap states; density of states; electrical performance; fixed charges; gate insulator/a-Si:H interface; interface states; nonlinearity; threshold voltage; two-dimensional analysis; valence-band-tail state; Conductive films; Conductivity; Contact resistance; Dielectric constant; Dielectric thin films; Dielectrics and electrical insulation; Electron mobility; Gaussian channels; Gaussian distribution; Threshold voltage;
Conference_Titel :
Active Matrix Liquid Crystal Displays, 1995. AMLCDs '95., Second International Workshop on
Conference_Location :
Bethlehem, PA
Print_ISBN :
0-7803-3056-0
DOI :
10.1109/AMLCD.1995.540957
