An integrated circuit has a P-type substrate and an N-type LDMOS transistor. The LDMOS transistor includes a boron-doped diffused well (DWELL-B) and an arsenic-doped diffused well (DWELL-As) located within the DWELL-B. A first polysilicon gate having first sidewall spacers and a second polysilicon gate having second sidewall spacers are located over opposite edges of the DWELL-B. A source/IBG region includes a first source region adjacent the first polysilicon gate, a second source region adjacent the second polysilicon gate, and an integrated back-gate (IBG) region located between the first and second source regions. The first source region and the second source region each include a lighter-doped source sub-region, the IBG region including an IBG sub-region having P-type dopants, and the source/IBG region includes a heavier-doped source sub-region.

A MOSFET device includes a semiconductor substrate, serving as a drain region, and an epitaxial region disposed on an upper surface of the substrate. The MOSFET device includes multiple body regions formed in the epitaxial region, and multiple source regions. The body regions are disposed near an upper surface of the epitaxial region and spaced laterally from one another, and each of the source regions is disposed in a corresponding one of the body regions near an upper surface of the body region. The MOSFET device includes a gate structure having multiple planar gates and a trench gate. Each of the planar gates is disposed on the upper surface of the epitaxial region overlapping a corresponding body region. The trench gate is formed partially through the epitaxial region and between the body regions, an upper surface of the trench gate being recessed below the upper surface of the epitaxial region.

Disclosed herein are field-effect transistors with asymmetric gate stacks. An example transistor includes a channel material and an asymmetric gate stack, provided over a portion of the channel material between source and drain (S/D) regions. The gate stack is asymmetric in that a thickness of a gate dielectric of a portion of the gate stack closer to one of the S/D regions is different from that of a portion of the gate stack closer to the other S/D region, and in that a work function (WF) material of a portion of the gate stack closer to one of the S/D regions is different from a WF material of a portion of the gate stack closer to the other S/D region. Transistors as described herein exploit asymmetry in the gate stacks to improve the transistor performance in terms of high breakdown voltage, high gain, and/or high output resistance.

A semiconductor device includes a semiconductor layer, a source region and a drain region that are formed in the semiconductor layer and at an interval in a first direction, a gate insulating film that is formed such as to cover a channel region between the source region and the drain region, and a gate electrode that is formed on the gate insulating film and opposes the channel region across the gate insulating film. The gate insulating film has a major portion on which the gate electrode is formed and extension portions projecting outward from each of both sides of the major portion in a second direction orthogonal to the first direction and leak current suppressing electrodes are formed on the extension portions.

Integrated circuit devices may include two transistor stacks including lower transistors having different threshold voltages and upper transistors having different threshold voltages. Gate insulators of the lower transistors may have different dipole elements or different areal densities of dipole elements, and the upper transistors may have different gate electrode structures.

A semiconductor device includes a semiconductor substrate, a gate dielectric film formed on the semiconductor substrate, a gate electrode formed on the gate dielectric film, a field plate portion which is integrally formed with the gate electrode, a step insulating film in contact with the field plate portion, a high dielectric constant film in contact with the step insulating film and having a higher dielectric constant than silicon.

A semiconductor device includes a semiconductor substrate, a first gate oxide layer, and a first source/drain doped region. The first gate oxide layer is disposed on the semiconductor substrate, and the first gate oxide layer includes a main portion and an edge portion having a sloping sidewall. The first source/drain doped region is disposed in the semiconductor substrate and located adjacent to the edge portion of the first gate oxide layer. The first source/drain doped region includes a first portion and a second portion. The first portion is disposed under the edge portion of the first gate oxide layer in a vertical direction, and the second portion is connected with the first portion.

A semiconductor device is provided. The semiconductor device includes a substrate, a first active pattern, which extends in a first direction on the substrate, a second active pattern, which extends in the first direction on the substrate and is spaced apart from the first active pattern by a first pitch in a second direction different from the first horizontal direction, a third active pattern, which extends in the first direction on the substrate and is spaced apart from the second active pattern by a second pitch greater than the first pitch in the second direction, a field insulating layer, which borders side walls of each of the first to third active patterns, a dam, which is between the first active pattern and the second active pattern on the field insulating layer, the region between the second active pattern and the third active pattern being free of the dam, a gate electrode, which extends in the second direction, and has a first portion on the first active pattern, a second portion on the second active pattern, and a third portion on the third active pattern, a first work function layer between the first portion of the gate electrode and the dam, and a second work function layer between the second portion of the gate electrode and the dam.

A power device includes: a semiconductor layer, a well region, a body region, a gate, a sub-gate, a source, a drain, and an electric field adjustment region. The sub-gate is formed above a top surface of the semiconductor layer, wherein a portion of the well region is located vertically beneath the sub-gate. The sub-gate is not directly connected to the gate. The electric field adjustment region has a conductivity type which is opposite to that of the well region. The electric field adjustment region is formed beneath and not in contact with the top surface of the semiconductor layer. The electric field adjustment region is located in the well region of the semiconductor layer, and at least a portion of the electric field adjustment region is located vertically beneath the sub-gate.

Some embodiments include a semiconductor construction having a gate extending into a semiconductor base. Conductively-doped source and drain regions are within the base adjacent the gate. A gate dielectric has a first segment between the source region and the gate, a second segment between the drain region and the gate, and a third segment between the first and second segments. At least a portion of the gate dielectric comprises ferroelectric material. In some embodiments the ferroelectric material is within each of the first, second and third segments. In some embodiments, the ferroelectric material is within the first segment or the third segment. In some embodiments, a transistor has a gate, a source region and a drain region; and has a channel region between the source and drain regions. The transistor has a gate dielectric which contains ferroelectric material between the source region and the gate.