A semiconductor device includes a gate dielectric layer and a gate electrode formed on the gate dielectric layer. The gate electrode includes a first metal layer, a second metal layer, and a third metal layer. The first metal layer includes an oxygen-gettering composition. The second metal layer includes oxygen. The third metal layer includes an interface with a polysilicon layer.

A semiconductor device includes a semiconductor layer including a trench, wherein the trench is adjacent a mesa, a first metal silicide layer on a top portion of the mesa, and a second metal silicide layer on a bottom portion of the trench. The first metal silicide layer has a thickness that is no more than about 1 to 1.5 times greater than a thickness of the second metal silicide layer. Related methods of forming a semiconductor device are disclosed.

The disclosure relates to a type trench gate silicon carbide MOSFET device and a fabrication method thereof. To protect a trench gate oxide layer without increasing a channel resistance and process complexity, a second conductivity type of heavily doped deep well inserted with double gate trenches along the sidewalls of deep well is designed. The deep well is connected to the source metal directly. The electric potential is clamped to the source during the voltage blocking and turn-off state, which reduces the electric field in the gate oxide and reduces the miller capacitance. An interlayer dielectric layer is deposited above the conductive dielectric polysilicon layers and extends outward separately to cover a part of the source region. A smaller cell pitch can be achieved by controlling the spacing between the first and the second trench gate, thereby increasing the channel density and reducing the channel resistance.

A device includes a first nanostructure; a second nanostructure over the first nanostructure; a first high-k gate dielectric around the first nanostructure; a second high-k gate dielectric around the second nanostructure; and a gate electrode over the first and second high-k gate dielectrics. The gate electrode includes a first work function metal; a second work function metal over the first work function metal; and a first metal residue at an interface between the first work function metal and the second work function metal, wherein the first metal residue has a metal element that is different than a metal element of the first work function metal.

According to an embodiment, a semiconductor device includes a first electrode, and a gate electrode, first and second insulating portions, and a second electrode. The semiconductor portion has a trench that extends along a first direction. The semiconductor portion includes first to third semiconductor layers. The gate electrode is disposed in the trench so as to face the second semiconductor layer and the third semiconductor layer along a second direction orthogonal to the first direction. The gate electrode has a facing surface formed at a position facing the third semiconductor layer so as to be away from the third semiconductor layer as the facing surface extends upward. The first insulating portion is continuously provided on the semiconductor portion and inside the trench. The second insulating portion is provided on the gate electrode. A material of the second insulating portion is different from a material of the first insulating portion.

A semiconductor device for high power application in which a novel semiconductor material having high mass productivity is provided. An oxide semiconductor film is formed, and then, first heat treatment is performed on the exposed oxide semiconductor film in order to reduce impurities such as moisture or hydrogen in the oxide semiconductor film. Next, in order to further reduce impurities such as moisture or hydrogen in the oxide semiconductor film, oxygen is added to the oxide semiconductor film by an ion implantation method, an ion doping method, or the like, and after that, second heat treatment is performed on the exposed oxide semiconductor film.