A semiconductor device with an active transistor cell comprising a p-doped first and second base layers, surrounding an n type source region, the device further comprising a plurality of first gate electrodes embedded in trench recesses, has additional fortifying p-doped layers embedding the opposite ends of the trench recesses. The additional fortifying layers do not affect the active cell design in terms of cell pitch i.e., the design rules for transistor cell spacing, or hole drainage between the transistor cells, but reduce the gate-collector parasitic capacitance of the semiconductor, hence leading to optimum low conduction and switching losses. To further reduce the gate-collector capacitance, the trench recesses embedding the first gate electrodes can be formed with thicker insulating layers in regions that do not abut the first base layers, so as not to negatively impact the value of the threshold voltage.

A semiconductor device includes a substrate including a first region, and a second region, a first gate structure and a second gate structure on the substrate of the first region, a third gate structure and a fourth gate structure on the substrate of the second region, a first interlayer insulating film on the substrate of the first region and including a first lower interlayer insulating film and a first upper interlayer insulating film, a second interlayer insulating film on the substrate of the second region and including a second lower interlayer insulating film and a second upper interlayer insulating film, a first contact between the first gate structure and the second gate structure and within the first interlayer insulating film, and a second contact formed between the third gate structure and the fourth gate structure and within the second interlayer insulating film.

A method for eliminating divot formation includes forming an isolation layer; forming a conduction layer which has an upper inclined boundary with the isolation layer such that the conduction layer has a portion located above a portion of the isolation layer at the upper inclined boundary; etching back the isolation layer; and etching back the conduction layer after etching back the isolation layer such that a top surface of the etched conduction layer is located at a level lower than a top surface of the etched isolation layer.

A method for eliminating divot formation includes forming an isolation layer; forming a conduction layer which has an upper inclined boundary with the isolation layer such that the conduction layer has a portion located above a portion of the isolation layer at the upper inclined boundary; etching back the isolation layer; and etching back the conduction layer after etching back the isolation layer such that a top surface of the etched conduction layer is located at a level lower than a top surface of the etched isolation layer.

The present disclosure provides a semiconductor device and a fabrication method thereof. The semiconductor device includes a III-nitride layer, a gate, a connection structure, and a gate bus. The gate is disposed over the III-nitride layer. The connection structure is disposed over the gate. The gate bus extends substantially in parallel to the gate and disposed over the connection structure from a top view perspective. The gate bus is electrically connected to the gate through the connection structure.

Example embodiments relate to a field-effect transistors having improved layouts. One example field-effect transistor includes a semiconductor substrate on which at least one transistor cell array is arranged. Each transistor cell includes a first transistor cell unit. Each first transistor cell unit includes a plurality of gate fingers, a main gate finger segment, a plurality of drain fingers, and a main drain finger segment. Each first transistor cell unit also includes a main gate finger base connected to the main gate finger segment of the first transistor cell unit and extending from that main gate finger segment towards the main drain finger segment of that first transistor cell unit. Further, each first transistor cell unit includes a main drain finger base connected to the main drain finger segment of that first transistor cell and extending from that main drain finger segment towards that main gate finger segment.

A method of manufacturing a transistor structure includes forming a plurality of trenches in a substrate, lining the plurality of trenches with a dielectric material, forming first and second substrate regions at opposite sides of the plurality of trenches, and filling the plurality of trenches with a conductive material. The plurality of trenches includes first and second trenches aligned between the first and second substrate regions, and filling the plurality of trenches with the conductive material includes the conductive material extending continuously between the first and second trenches.

A semiconductor device includes an isolation structure in a substrate. The semiconductor device further includes a gate structure over a first region of the substrate, wherein the isolation structure surrounds the first region, the gate structure comprising a first section and a second section. The semiconductor device further includes a conductive field plate over the substrate, the conductive field plate extending between the first section and the second section and overlapping an edge of the first region, wherein the conductive field plate comprises a dielectric layer having a variable thickness. The semiconductor device further includes a first well in the substrate, wherein the first well overlaps the edge of the first region, and the first well extends underneath the isolation structure, and the conductive field plate extends beyond an outer-most edge of the first well.

A standard cell includes: a gate interconnect; a dummy gate interconnect formed to be adjacent to the gate interconnect on the right side of the gate interconnect in the figure in the X direction; a pad provided between the gate interconnect and the dummy gate interconnect; a nanosheet formed to overlap the gate interconnect as viewed in plan and connected with the pad; and a dummy nanosheet formed to overlap the dummy gate interconnect as viewed in plan and connected with the pad.

Trenches having a gate oxide layer are formed in the surface of a silicon wafer for vertical gates. Conductive doped polysilicon is then deposited in the trenches to form a relatively thin layer of doped polysilicon along the sidewalls. Thus, there is a central cavity surrounded by polysilicon. Next, the cavity is filled in with a much higher conductivity material, such as aluminum, copper, a metal silicide, or other conductor to greatly reduce the overall resistivity of the trenched gates. The thin polysilicon forms an excellent barrier to protect the gate oxide from diffusion from the inner conductor atoms. The inner conductor and the polysilicon conduct the gate voltage in parallel to lower the resistance of the gates, which increases the switching speed of the device. In another embodiment, a metal silicide is used as the first layer, and a metal fills the cavity.