The present disclosure provides a bio-field effect transistor (BioFET) and a method of fabricating a BioFET device. The method includes forming a BioFET using one or more process steps compatible with or typical to a complementary metal-oxide-semiconductor (CMOS) process. The BioFET device may include a substrate; a gate structure disposed on a first surface of the substrate and an interface layer formed on the second surface of the substrate. The interface layer may allow for a receptor to be placed on the interface layer to detect the presence of a biomolecule or bio-entity. An amplification factor of the BioFET device may be provided by a difference in capacitances associated with the gate structure on the first surface and with the interface layer formed on the second surface.

In a semiconductor device including a transistor, the transistor is provided over a first insulating film, and the transistor includes an oxide semiconductor film over the first insulating film, a gate insulating film over the oxide semiconductor film, a gate electrode over the gate insulating film, a second insulating film over the oxide semiconductor film and the gate electrode, and a source and a drain electrodes electrically connected to the oxide semiconductor film. The first insulating film includes oxygen. The second insulating film includes hydrogen. The oxide semiconductor film includes a first region in contact with the gate insulating film and a second region in contact with the second insulating film. The first insulating film includes a third region overlapping with the first region and a fourth region overlapping with the second region. The impurity element concentration of the fourth region is higher than that of the third region.

A semiconductor device in which parasitic capacitance is reduced is provided. A first oxide insulating layer and a first oxide semiconductor layer are sequentially formed over a first insulating layer. A first conductive layer is formed over the first oxide semiconductor layer and etched to form a second conductive layer. The first oxide insulating layer and the first oxide semiconductor layer are etched with the second conductive layer as a mask to form a second oxide insulating layer and a second oxide semiconductor layer. A planarized insulating layer is formed over the first insulating layer and the second conductive layer. A second insulating layer, a source electrode layer, and a drain electrode layer are formed by etching the planarized insulating layer and the second conductive layer. A third oxide insulating layer, a gate insulating layer, and a gate electrode layer are formed over the second oxide semiconductor layer.

A highly reliable semiconductor device suitable for miniaturization and high integration is provided. The semiconductor device includes a first transistor, a first insulator over the first transistor, a second transistor over the first insulator, a second insulator over the second transistor, and a capacitor over the second insulator. The first insulator has a barrier property against oxygen and hydrogen. The second transistor includes an oxide semiconductor. The second insulator includes an oxygen-excess region. The capacitor includes a first electrode, a second electrode, and a dielectric between the first electrode and the second electrode. The dielectric includes a third insulator having a barrier property against oxygen and hydrogen. The first insulator and the third insulator are in contact with each other on an outer edge of a region where the second transistor is located so that the second transistor and the second insulator are enclosed by the first insulator and the third insulator.

A semiconductor device that can retain data for a long time is provided. The semiconductor device includes a first transistor and a second transistor. The first transistor contains an oxide semiconductor in a channel formation region. The second transistor includes a first gate and a second gate. A gate of the first transistor is connected to a first electrode of the first transistor. The first electrode of the first transistor is connected to the second gate. A negative potential is applied to a second electrode of the first transistor. The first electrode and the second electrode of the first transistor include a first end portion and a second end portion, respectively. The first end portion and the second end portion face each other. The first end portion includes a first arc and the second end portion includes a second arc when seen from the top. The radius of curvature of the second arc is larger than that of the first arc.

The present disclosure discloses in embodiments a thin film transistor and a manufacturing method thereof, an array substrate. The thin film transistor comprises: a base substrate, an active layer, a source, a gate, and a drain. Two ends of the active layer are connected to the source and the drain, respectively. The gate comprises a top gate and a bottom gate arranged opposite to each other in a direction perpendicular to the base substrate, the top gate comprising a top gate top portion and a top gate side portion connected to the top gate top portion, the top gate side portion extending from the top gate top portion towards the base substrate. The active layer is sandwiched between the top gate top portion and the bottom gate. A sidewall of the active layer is at least partially surrounded by the top gate side portion.

To provide a semiconductor device having a structure capable of suppressing deterioration of its electrical characteristics which becomes apparent with miniaturization. The semiconductor device includes a first oxide semiconductor film over an insulating surface; a second oxide semiconductor film over the first oxide semiconductor film; a source electrode and a drain electrode in contact with the second oxide semiconductor film; a third oxide semiconductor film over the second oxide semiconductor film, the source electrode, and the drain electrode; a gate insulating film over the third oxide semiconductor film; and a gate electrode over the gate insulating film. A first interface between the gate electrode and the gate insulating film has a region closer to the insulating surface than a second interface between the first oxide semiconductor film and the second oxide semiconductor film.

In an aspect of the present invention, a graphene field-effect transistor (GFET) structure is formed. The GFET structure comprises a wider portion and a narrow extension portion extending from the wider portion that includes one or more graphene layers edge contacted to source and drain contacts, wherein the source and drain contacts are self-aligned to the one or more graphene layers.

A display device including: a first base substrate including a display area and a non-display area adjacent to the display area; a plurality of signal lines disposed in the display area; a plurality of pixels disposed in the display area and connected to the signal lines; and a driving circuit disposed in the non-display area and configured to provide driving signals to the signal lines. Each of the pixels includes a switching transistor connected to a corresponding signal line, and a display element connected to the switching transistor.

A thin film transistor, an array substrate and manufacturing method thereof, and a display device are provided. The thin film transistor includes an active layer, a source electrode, a drain electrode, and a first gate electrode, the first gate electrode is shaped in a ring. The active layer includes a first portion, a second portion and a third portion for connecting the first portion and the second portion. The first portion and the second portion are disposed horizontally, and connected to the source electrode and the drain electrode, respectively. The third portion is disposed obliquely, and has a channel provided thereon. At least one part of the channel is located on an inner side of the first gate electrode. The thin film transistor can be used in a display device.