Title :
A New Model for the 1/f Noise of Polycrystalline Silicon Thin-Film Transistors
Author :
Mingxiang Wang ; Ming Wang
Author_Institution :
Dept. of Microelectron., Soochow Univ., Suzhou, China
Abstract :
An alternative model for the 1/f noise of polycrystalline Si thin-film transistors (poly-Si TFTs) is developed. The model adequately incorporates the grain boundary (GB) effect, different from previous work, however, the current noise is attributed to fluctuations in both carrier number and the GB barrier caused by carrier trapping/detrapping between the channel inversion carriers and the intragrain traps within the GB depletion region. The large dispersion of the trapping time constants in the 1/f noise behavior is attributed to the variation in carrier tunneling distance. The model fits the noise data very well in the low-drain current region. Based on the model, the effective density of states of the intragrain traps is obtained, providing a feasible method to evaluate the grain quality of poly-Si TFTs.
Keywords :
electron traps; elemental semiconductors; grain boundaries; hole traps; semiconductor device models; semiconductor device noise; semiconductor thin films; silicon; thin film transistors; 1/f noise behavior; GB barrier; GB depletion region; GB effect; Si; carrier number; carrier trapping-detrapping; carrier tunneling distance; channel inversion carriers; grain boundary effect; intragrain traps; polycrystalline silicon thin-film transistors; state density; time constant trapping; 1f noise; Charge carrier processes; Mathematical model; Semiconductor device modeling; Thin film transistors; Tunneling; 1/f noise; intragrain traps; noise; polycrystalline Si thin-film transistors (poly-Si TFTs);
Journal_Title :
Electron Devices, IEEE Transactions on
DOI :
10.1109/TED.2014.2336250
