Abstract: Disclosed is a thin film transistor that is provided with a gate insulating film that is inexpensive, and that is less likely to have a low-density microcrystalline silicon layer formed thereon due to plasma induced damage, while suppressing fluctuation of a threshold voltage. In a TFT (100) having the bottom gate structure, since a silicon nitride film (31) having a natural oxide film (32) formed on the surface thereof is used as the gate insulating film (30), the gate insulating film (30) is not only capable of preventing the alkali metal ions contained in a glass substrate (10) from entering the gate insulating film (30), but also capable of suppressing a formation of the low-density microcrystalline silicon layer on the surface of a microcrystalline silicon film (41) on the side in contact with the gate insulating film (30). Since the mobility of the microcrystalline silicon film (41) is increased, the operation speed of the TFT (100) can be improved.

Abstract: It is an object to increase the mobility of a thin film transistor having an active layer including a microcrystalline semiconductor film. Upon fabricating an inverted staggered type TFT 10, a substrate is vacuum-transferred to a plasma enhanced CVD apparatus such that a surface of a microcrystalline silicon film (active layer 40) exposed by gap etching is not exposed to the air. An insulating film 80 is deposited by the plasma enhanced CVD apparatus so as to completely cover the exposed surface of the microcrystalline silicon film. By this, even if the microcrystalline silicon film is exposed to the air, oxygen cannot be adsorbed on the surface thereof and thus diffusion of oxygen into the microcrystalline silicon film can be suppressed. In addition, since N+ silicon films composing contact layers 50a and 50b directly contact with the microcrystalline silicon film, the contact resistance can be reduced.

Abstract: Disclosed is a thin film transistor that is provided with a gate insulating film that is inexpensive, and that is less likely to have a low-density microcrystalline silicon layer formed thereon due to plasma induced damage, while suppressing fluctuation of a threshold voltage. In a TFT (100) having the bottom gate structure, since a silicon nitride film (31) having a natural oxide film (32) formed on the surface thereof is used as the gate insulating film (30), the gate insulating film (30) is not only capable of preventing the alkali metal ions contained in a glass substrate (10) from entering the gate insulating film (30), but also capable of suppressing a formation of the low-density microcrystalline silicon layer on the surface of a microcrystalline silicon film (41) on the side in contact with the gate insulating film (30). Since the mobility of the microcrystalline silicon film (41) is increased, the operation speed of the TFT (100) can be improved.

Abstract: A method for fabricating a semiconductor device according to the present invention includes the steps of: (a) providing a substrate (11a) in a chamber (26); (b) supplying a microwave into the chamber (26) through a dielectric plate (24), of which one surface that faces the chamber is made of alumina, thereby depositing a microcrystalline silicon film (14) with an aluminum concentration of 1.0×1016 atoms/cm3 or less on the substrate (11a) by high-density plasma CVD process; and (c) making a thin-film transistor that uses the microcrystalline silicon film as its active layer. As a result, a semiconductor device including a TFT that uses a microcrystalline silicon film with a mobility of more than 0.5 cm2/Vs as its active layer is obtained.

Abstract: A semiconductor film comprising a polycrystalline semiconductor film provided on a substrate having an insulating surface. Nearly all crystal orientation angle differences between adjacent crystal grains constituting the polycrystalline semiconductor film are present in the ranges of less than 10° or 58°-62°.

Abstract: A semiconductor film comprising a polycrystalline semiconductor film provided on a substrate having an insulating surface. Nearly all crystal orientation angle differences between adjacent crystal grains constituting the polycrystalline semiconductor film are present in the ranges of less than 10° or 58°-62°.

Abstract: A semiconductor film comprising a polycrystalline semiconductor film provided on a substrate having an insulating surface. Nearly all crystal orientation angle differences between adjacent crystal grains constituting the polycrystalline semiconductor film are present in the ranges of less than 10° or 58°-62°.