| 摘要 |
PURPOSE:To reduce extremely threshold voltage by using the active layer of polycrystalling silicon thin film whose film thickness is at most 100Angstrom . CONSTITUTION:The film thickness of a polycrystal silicon thin film 2 composing an active layer is made 20-100Angstrom . When a gate electrode 6 is applied a conventional high gate voltage, the film thickness of an active layer 2a becomes thinner than that of a channel induced in this active layer 2a, therefore the threshold voltage Vth decreases according as an effective mobility mueff becomes bigger. The resistance of the active layer 2a can be big by its appearance and the cubage of this active layer 2a can be small according as the film thickness of polycrystalline silicon thin film 2 becomes thin, therefore, the leak current between a sauce region 3 and a drain region 4 by an external light can be reduced. |
