A semiconductor device and a forming method thereof, the semiconductor device includes a first and a second wells, a source region, a drain region, two gate structures and at least one doping region. The first well with a first conductive type is disposed in a substrate, and the source region is disposed in the first well. The second well with a second conductive type is disposed adjacent to the first well in a substrate, and the drain region is disposed in the second well. Two gate structures are disposed on the substrate between the source region and the drain region. At least one doping region with the first conductive type is disposed in the second well between the two gate structures.

In a semiconductor manufacturing method, a mask is disposed on a semiconductor layer or semiconductor substrate. The semiconductor layer or semiconductor substrate is etched in an area delineated by the mask to form a cavity. With the mask disposed on the semiconductor layer or semiconductor substrate, the cavity is lined to form a containment structure. With the mask disposed on the semiconductor layer or semiconductor substrate, the containment structure is filled with a base semiconductor material. After filling the containment structure with the base semiconductor material, the mask is removed. At least one semiconductor device is fabricated in and/or on the base semiconductor material deposited in the containment structure.

A semiconductor device includes a substrate, a gate trench in the substrate, a gate insulating film in the gate trench, a titanium nitride (TiN)-lower gate electrode film on the gate insulating film, the titanium nitride (TiN)-lower gate electrode film including a top surface, a first side surface, and a second side surface opposite the first side surface, a polysilicon-upper gate electrode film on the titanium nitride (TiN)-lower gate electrode film, and a gate capping film on the polysilicon-upper gate electrode film. A center portion of the top surface of the titanium nitride (TiN)-lower gate electrode film overlaps a center portion of the polysilicon-upper gate electrode film in a direction that is perpendicular to a top surface of the substrate, and each of the first side surface and the second side surface of the titanium nitride (TiN)-lower gate electrode film is connected to the gate insulating film.

A semiconductor device includes a source region, a drain region, and a gate insulating film formed on a substrate, a gate electrode formed on the gate insulating film, a first insulating film pattern formed to extend from the source region to a part of a top surface of the gate electrode, and a spacer formed on a side surface of the gate electrode in a direction of the drain region.

A semiconductor device includes a source/drain diffusion area, a first doped region and a gate. The source/drain diffusion area, defined between a first isolation structure and a second isolation structure, includes a source region, a drain region and a device channel. The first doped region, disposed along a first junction between the device channel and the first isolation structure, is separated from at least one of the source region and the drain region. The first doped region has a dopant concentration higher than that of the device channel. The gate is disposed over the source/drain diffusion area. The first doped region is located within a projected area of the gate onto the source/drain diffusion area, the first isolation structure and the second isolation structure. A length of the first doped region is shorter than a length of the gate in a direction from the source region to the drain region.

Various embodiments of the present disclosure are directed towards a semiconductor device. The semiconductor device comprises a source region and a drain region in a substrate and laterally spaced. A gate stack is over the substrate and between the source region and the drain region. The drain region includes two or more first doped regions having a first doping type in the substrate. The drain region further includes one or more second doped regions in the substrate. The first doped regions have a greater concentration of first doping type dopants than the second doped regions, and each of the second doped regions is disposed laterally between two neighboring first doped regions.

In the semiconductor device, a high-concentration diffusion layer and a low-concentration diffusion layer are disposed around a drain diffusion layer of an ESD protection element. The high-concentration diffusion layer is separated from a gate electrode, and a medium concentration LDD diffusion layer is disposed in a separation gap. Variations in characteristics are suppressed by reducing thermal treatment on the high-concentration diffusion layer and a medium concentration diffusion layer.

The source region, drain region, buried insulating film, gate insulating film, and gate electrode of the semiconductor device are formed in a main surface of a semiconductor substrate. The buried insulating film is buried in a first trench formed between the source and drain regions. The first trench has a first side surface and a first bottom surface. The first side surface faces the source region in a first direction extending from one of the source and drain regions to the other. The first bottom surface is connected to the first side surface and is along the main surface of the semiconductor substrate. A crystal plane of a first surface of the semiconductor substrate, which is the first side surface of the first trench, is (111) plane. A crystal plane of a second surface of the semiconductor substrate, which is the bottom surface of the first trench, is (100) plane.

A semiconductor device includes a P-type body region and an N-type drift region disposed in a substrate; a gate electrode, disposed on the P-type body region and the N-type drift region, including a high concentration doping region and a high resistance region, wherein a dopant concentration of the high concentration doping region is higher than a dopant concentration of the high resistance region; a spacer disposed on a side of the gate electrode; a highly doped source region disposed in the P-type body region; and a highly doped drain region disposed in the N-type body region. The high concentration doping region overlaps the P-type body region, and the high resistance region overlaps the N-type drift region.

Structures for a field-effect transistor and methods of forming a structure for a field-effect transistor. A gate structure is arranged over a channel region of a semiconductor body. A first source/drain region is coupled to a first portion of the semiconductor body, and a second source/drain region is located in a second portion the semiconductor body. The first source/drain region includes an epitaxial semiconductor layer containing a first concentration of a dopant. The second source/drain region contains a second concentration of the dopant. The channel region is positioned in the semiconductor body between the first source/drain region and the second source/drain region.