Dependence of thin film transistor characteristics on the deposition conditions of silicon nitride and amorphous silicon

The systematic relation between thin film transistors' (TFT's) characteristics and the deposition conditions of amorphous silicon nitride (a-SiN) films and hydrogenated amorphous silicon (a-Si:H) films is investigated. It is observed that field effect mobility /spl mu//sub FE/ and threshold voltage V/sub th/ of the TFT's strongly depend on the deposition conditions of these films. The maximum /spl mu//sub FE/ of 0.88 cm/sup 2//V/spl middot/s is obtained for the TFT of which a-SiN film is deposited at a pressure of 85 Pa. This phenomenon is due to the variation of the interface states density between a-Si:H film and a-SiN film.<
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