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.

A high frequency transistor includes a first semiconductor layer, a first insulating film and a control electrode. The first semiconductor layer on the first insulating film extends in a first direction along an upper surface of the first insulating film. The first semiconductor layer has a first layer thickness in a second direction perpendicular to the upper surface, and a first width in a third direction orthogonal to the first direction. The first width is greater than the first layer thickness. The control electrode covers upper and side surfaces of the first semiconductor layer. The first semiconductor layer includes a first region of a first conductivity type, second and third regions of a second conductivity type. The first to third regions are arranged in the first direction. The first region is provided between the second and third region. The control electrode covers the first region.

The invention provides a manufacturing method of a semiconductor structure, the method includes providing a substrate, forming two shallow trench isolation structures in the substrate. A first region, a second region and a third region are defined between the two shallow trench isolation structures, and the second region is located between the first region and the third region. Next, an oxide layer is formed in the first region, the second region and the third region, and the oxide layer directly contacts the two shallow trench isolation structures. The oxide layer in the second region is then removed, and another oxide layer is formed in the first region, the second region and the third region, so that a thick oxide layer is formed in the first and third regions, and a thin oxide layer is formed in the second region.

A semiconductor structure is provided, and the semiconductor structure includes a substrate, and an active area is defined thereon, a gate structure spanning the active area, wherein the overlapping range of the gate structure and the active area is defined as an overlapping region, and the overlapping region includes four corners, and at least one salicide block covering the four corners of the overlapping region.

An IC includes a first and second active areas (AA) with a second conductivity type, a source and drain region, and an LDD extension to the source and drain in the first AA having a first conductivity type. A first bent-gate transistor includes a first gate electrode over the first AA extending over the corresponding LDD. The first gate electrode includes an angled portion that crosses the first AA at an angle of 45° to 80°. A second transistor includes a second gate electrode over the second AA extending over the corresponding LDD including a second gate electrode that can cross an edge of the second AA at an angle of about 90°. A first pocket distribution of the second conductivity type provides a pocket region under the first gate electrode. A threshold voltage of the first bent-gate transistor is ≥30 mV lower as compared to the second transistor.

A semiconductor device of an embodiment includes: a first and second semiconductor regions of a first conductivity type; a third semiconductor region of a second conductivity type disposed between the first and second semiconductor regions; a fourth semiconductor region of the first conductivity type disposed below the first semiconductor region; a fifth semiconductor region of the first conductivity type disposed below the second semiconductor region; a first region containing carbon disposed between the first and fourth semiconductor regions; a second region containing carbon disposed between the second and fifth semiconductor regions; a third region disposed between the first and second regions; the first and second regions having a first and second carbon concentrations respectively, the third region not containing carbon or having a lower carbon concentration than the first and second carbon concentrations in a portion below an end of a lower face of a gate electrode.

A transistor structure includes a gate conductive region, a gate dielectric region, a channel region and a drain region. The gate conductive region is below an original surface of a substrate. The gate dielectric region surrounds the gate conductive region. The channel region surrounds the gate dielectric region. The drain region is horizontally spaced apart from the gate conductive region, wherein the drain region includes a highly doped region; wherein the gate dielectric region includes a first dielectric portion and a second dielectric portion, the first dielectric portion is positioned between the gate conductive region and the highly doped region, and the second dielectric portion is positioned between the gate conductive region and the channel region; wherein a horizontal thickness of the first dielectric portion is greater than that of the second dielectric portion.

A level shifter circuit for translating input signal to output signal is disclosed. The level shifter includes an input stage and a latch stage. The latch stage comprises at least a transistor characterized in a substantially matched transconductance with the input stage for preventing a discrete realization of a voltage clamp circuit. The transistor is a semiconductor device including a source region having a source doping region and a drain region having a first doping region and a second doping region. The first doping region is doped with a first conductivity impurity. The second doping region is disposed around the first doping region so as to surround the first doping region, and is doped with a second conductivity impurity. The second doping region has a higher on-resistance than the first doping region, thereby a high resistive series path is created by the second doping region to mimic an embedded resistor.

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 structure is disclosed. The semiconductor structure includes: a substrate of a first conductivity; a first region of the first conductivity formed in the substrate; a second region of the first conductivity formed in the first region, wherein the second region has a higher doping density than the first region; a source region of a second conductivity formed in the second region; a drain region of the second conductivity formed in the substrate; a pickup region of the first conductivity formed in the second region and adjacent to the source region; and a resist protective oxide (RPO) layer formed on a top surface of the second region. An associated fabricating method is also disclosed.