A method for manufacturing a highly reliable semiconductor device is provided. The method includes the steps of: forming an oxide semiconductor film at a first temperature; processing the oxide semiconductor film into an island shape; not performing a process at a temperature higher than the first temperature, but depositing a material to be source and drain electrodes by a sputtering method; processing the material to form the source and drain electrodes; forming a protective insulating film, and then forming a first barrier film; adding excess oxygen or oxygen radicals to the protective insulating film through the first barrier film; performing heat treatment at a second temperature lower than 400° C. to diffuse the excess oxygen or oxygen radicals into the oxide semiconductor film; and removing part of the first barrier film and part of the protective insulating film by wet etching, and then forming a second barrier film.

A semiconductor device includes an insulating substrate, a first semiconductor layer formed of silicon and positioned above the insulating substrate, a second semiconductor layer formed of a metal oxide and positioned above the first semiconductor layer, a first insulating film formed of a silicon nitride and positioned between the first semiconductor layer and the second semiconductor layer, and a block layer positioned between the first semiconductor film and the second semiconductor layer, the block layer hydrogen diffusion of which is lower than that of the first insulating film.

A display apparatus can include a driving circuit on a device substrate, the driving circuit including a first thin film transistor and a second thin film transistor, a first insulating layer on the first thin film transistor and the second thin film transistor of the driving circuit, a second insulating layer on the first insulating layer, and a light-emitting device on the second insulating layer, the light-emitting device being electrically connected to the second thin film transistor of the driving circuit. Each of the first thin film transistor and the second thin film transistor includes an oxide semiconductor pattern and a gate electrode overlapping a portion of the oxide semiconductor pattern. The gate electrode has a stacked structure of a first hydrogen barrier layer and a low-resistance electrode.

a thin-film transistor according to an exemplary embodiment of the present invention comprises an active layer; an intermediate layer; a gate insulating film; a gate electrode; an interlayer insulating film; and source and drain electrodes. The active layer is positioned on a substrate, and the gate insulating film is positioned on the active layer. The gate electrode is positioned on the gate insulating film, and the interlayer insulating film is positioned on the gate electrode. The source and drain electrodes are positioned on the interlayer insulating film and connected to the active layer. The intermediate layer is positioned between the active layer and the gate insulating film, and made of an oxide semiconductor comprising a Group IV element.

Integrated circuit (IC) strata including one or more transistor and one or more semiconductor diode. A transistor may include one or more non-planar semiconductor bodies in which there is a channel region while the diode also includes one or more non-planar semiconductor bodies in which there is a p-type region, an n-type region, or both. One IC stratum may be only hundreds of nanometers in thickness and include both front-side and back-side interconnect levels. The front-side interconnect level is disposed over a front side of one or more of the non-planar semiconductor bodies and is coupled to at least one terminal of the transistor. The back-side interconnect level is disposed over a back side of one or more of the non-planar semiconductor bodies and is coupled to at least one terminal of the semiconductor diode.

A semiconductor device with high on-state current is provided. The semiconductor device includes a transistor. The transistor includes a first insulator; a first oxide over the first insulator; a second oxide over the first oxide; a third oxide; a first conductor and a second conductor over the second oxide; a second insulator; a third conductor; a fourth insulator over the first conductor and the second conductor; and a third insulator over the fourth insulator. An opening reaching the second oxide is provided in the third insulator and the fourth insulator. The third oxide is positioned to cover an inner wall of the opening. The second insulator is positioned to cover the inner wall of the opening with the third oxide therebetween. The third conductor is positioned to fill the opening with the third oxide and the second insulator therebetween. In the channel length direction of the transistor, an angle formed by a bottom surface of the first insulator and a side surface of the first conductor facing the second conductor is smaller than 90°.

An object is to provide a high reliability thin film transistor using an oxide semiconductor layer which has stable electric characteristics. In the thin film transistor in which an oxide semiconductor layer is used, the amount of change in threshold voltage of the thin film transistor before and after a BT test is made to be 2 V or less, preferably 1.5 V or less, more preferably 1 V or less, whereby the semiconductor device which has high reliability and stable electric characteristics can be manufactured. In particular, in a display device which is one embodiment of the semiconductor device, a malfunction such as display unevenness due to change in threshold voltage can be reduced.

A method for fabricating a metal oxide thin film transistor comprises selecting a substrate and fabricating a gate electrode thereon; growing a layer of dielectric or high permittivity dielectric on the substrate to serve as a gate dielectric layer; growing a first metal layer on the gate dielectric layer and a second metal layer on the first metal layer; fabricating a channel region at a middle position of the first metal layer and a passivation region at a middle position of the second metal layer; anodizing the metals of the passivation region and the channel region at atmospheric pressure and room temperature; fabricating a source and a drain; forming an active region comprising the source, the drain, and the channel region; depositing a silicon nitride layer on the active region; fabricating two electrode contact holes; depositing a metal aluminum film; and fabricating two metal contact electrodes by photolithography and etching.

Provided is a semiconductor device which has a double-gate structure with a channel layer made of an oxide semiconductor and is capable of inhibiting the occurrence of hysteresis.

A TFT having a double-gate structure with a channel layer 40 made of an oxide semiconductor uses a passivation film (70), which is a film stack obtained by stacking, sequentially from the side closest to the channel layer (40), a silicon oxide film (71), a first silicon nitride film (73), and a second silicon nitride film (74). In this case, the second silicon nitride film (74) farthest from the channel layer (40) is formed so as to have a higher hydrogen content than the first silicon nitride film (73) closer to the channel layer (40). Thus, it is rendered possible to inhibit the shifting of a threshold voltage of the TFT (100) resulting from hydrogen spreading in the channel layer (40), and at the same time, it is also rendered possible to diminish hysteresis and thereby inhibit the shifting of the threshold voltage caused by hysteresis.

A method is provided for manufacturing a thin film transistor (TFT) backplate that includes a switch TFT and a drive TFT. The method is conducted such that each of the switch TFT and the drive TFT manufactured therewith includes a source electrode/a drain electrode and a gate electrode, and also includes an etching stopper layer, a semiconductor layer, and gate isolation layer that are disposed between the source electrode/the drain electrode and the gate electrode to form a TFT structure. The gate isolation layers of the switch TFT and drive TFT are formed of different materials, such as SiOx and Al.sub.2O.sub.3, or SiOx and SiNx, or Al.sub.2O.sub.3 and a mixture of SiNx and SiOx, such that electrical properties of the switch TFT and the drive TFT are made different.