Semiconductor structures including electrical isolation and methods of forming a semiconductor structure including electrical isolation. The structure includes a semiconductor substrate having a first surface, a recess in the first surface, and a second surface inside the first recess. The structure further includes a shallow trench isolation region extending from the first surface into the semiconductor substrate. The shallow trench isolation region is positioned to surround an active device region including the recess. A field-effect transistor includes a gate electrode positioned on a portion of the second surface.

An integrated circuit is formed on a semiconductor substrate and includes a trench conductor and a first transistor formed on the surface of the substrate. The transistor includes: a transistor gate structure, a first doped region extending in the substrate between a first edge of the gate structure and an upper edge of the trench conductor, and a first spacer formed on the first edge of the gate structure and above the first doped region. The first spacer completely covers the first doped region and a silicide is present on the trench conductor but is not present on the surface of the first doped region.

A semiconductor device includes a substrate and a p-doped layer including a doped III-V material on the substrate. A dielectric interlayer is formed on the p-doped layer. An n-type layer is formed on the dielectric interlayer, the n-type layer including a high band gap II-VI material to form an electronic device.

A plurality of gate trenches is formed into a semiconductor substrate in an active cell region. One or more other trenches are formed in a different region. Each gate trench has a first conductive material in lower portions and a second conductive material in upper portions. In the gate trenches, a first insulating layer separates the first conductive material from the substrate, a second insulating layer separates the second conductive material from the substrate and a third insulating material separates the first and second conductive materials. The other trenches contain part of the first conductive material in a half-U shape in lower portions and part of the second conductive material in upper portions. In the other trenches, the third insulating layer separates the first and second conductive materials. The first insulating layer is thicker than the third insulating layer, and the third insulating layer is thicker than the second.

A unit pixel formed on a substrate and configured to convert incident light to an electrical signal is provided. The unit pixel includes: a source having a source voltage supplied thereto and having a silicide layer for metal contact formed thereabove; a drain spaced apart from the source and having a silicide layer for metal contact formed thereabove; a channel formed between the source and the drain and having a current flowed therethrough; an insulating layer formed above the channel; and a floating gate having a nonsal structure in which no silicide layer is formed thereabove in order to facilitate an absorption of light, formed above the insulating layer so as to be placed between the source and the drain, and configured to control an amount of current flowing through the channel by an electric field generated by electron-hole pairs generated by the incident light. A body of the unit pixel is floated, and the electric field is configured to act on the channel by electrons aggregated toward the source and holes aggregated toward the drain by the source voltage supplied to the source.

A MOS pass transistor includes a semiconductor layer having first conductivity, a trench isolation layer disposed in the semiconductor layer to define a first active region and a second active region, a first junction region having second conductivity, disposed in the first active region, and being in contact with a first sidewall of the trench isolation layer, a second junction region having the second conductivity, disposed in the second active region, being in contact with a second sidewall of the trench isolation layer, and being spaced apart from the first junction region, and a gate electrode disposed over the trench isolation layer. A lower portion of the gate electrode extends from a top surface of the trench isolation layer into the trench isolation layer to a predetermined depth.

Nanowire-based gate all-around transistor devices having one or more active nanowires and one or more inactive nanowires are described herein. Methods to fabricate such devices are also described. One or more embodiments of the present invention are directed at approaches for varying the gate width of a transistor structure comprising a nanowire stack having a distinct number of nanowires. The approaches include rendering a certain number of nanowires inactive (i.e. so that current does not flow through the nanowire), by severing the channel region, burying the source and drain regions, or both. Overall, the gate width of nanowire-based structures having a plurality of nanowires may be varied by rendering a certain number of nanowires inactive, while maintaining other nanowires as active.

Various embodiments of the present disclosure provide a method for forming a recessed gate electrode that has high thickness uniformity. A gate dielectric layer is deposited lining a recess, and a multilayer film is deposited lining the recess over the gate dielectric layer. The multilayer film comprises a gate electrode layer, a first sacrificial layer over the gate dielectric layer, and a second sacrificial layer over the first sacrificial dielectric layer. A planarization is performed into the second sacrificial layer and stops on the first sacrificial layer. A first etch is performed into the first and second sacrificial layers to remove the first sacrificial layer at sides of the recess. A second etch is performed into the gate electrode layer using the first sacrificial layer as a mask to form the recessed gate electrode. A third etch is performed to remove the first sacrificial layer after the second etch.

A process forms a high electron mobility transistor (HEMT) device with a recessed gate without damaging sensitive areas of the HEMT device. The process utilizes a first epitaxial growth process to grow a first set of layers of the HEMT. The epitaxial growth process is then stopped and a passivation layer is formed on the first set of layers. The passivation layer is then patterned to provide a passivation structure at a desired location of the recessed gate electrode. The channel layer and one or more barrier layers are then formed in a second epitaxial growth process in the presence of the passivation structure. The result is that the channel layer and the barrier layer growth around the passivation structure. The passivation structure is then removed, effectively leaving a recess in the channel layer. The gate electrode is then formed in the recess.

A MOS pass transistor includes a semiconductor layer having first conductivity, a trench isolation layer disposed in the semiconductor layer to define a first active region and a second active region, a first junction region having second conductivity, disposed in the first active region, and being in contact with a first sidewall of the trench isolation layer, a second junction region having the second conductivity, disposed in the second active region, being in contact with a second sidewall of the trench isolation layer, and being spaced apart from the first junction region, and a gate electrode disposed over the trench isolation layer. A lower portion of the gate electrode extends from a top surface of the trench isolation layer into the trench isolation layer to a predetermined depth.