The present invention relates generally to integrated circuits and more particularly, to a structure and method of forming a hybrid circuit including a tunnel field-effect transistor (TFET) and a conventional field effect transistor (FET). Embodiments of the present invention include a hybrid amplifier which features a TFET common-source feeding a common-gate conventional FET (e.g. a MOSFET). A TFET gate may be electrically isolated from an output from a conventional FET. Thus, a high impedance input may be received by a TFET with a high-isolation output (i.e. low capacitance) at a conventional FET. A hybrid circuit amplifier including a TFET and a conventional FET may have a very high input impedance and a low miller capacitance.

Some embodiments of the present disclosure provide a semiconductor structure, including a substrate having a top surface; a first doped region in proximity to the top surface; a non-doped region positioned in proximity to the top surface and adjacent to the first doped region, having a first width; a metal gate positioned over the non-doped region and over a portion of the first doped region, having a second width. The first width is smaller than the second width, and material constituting the non-doped region is different from material constituting the substrate.

A semiconductor device includes: an n-type first source region and first drain region formed in a surface of a p-type epitaxial layer; an n-type first source drift region and first drain drift region formed so as to individually surround the first source region and the first drain region; and a p-type first diffusion region formed in a first channel region and having a higher concentration than the epitaxial layer, the semiconductor device having p-type first withstand voltage maintaining regions formed between the first diffusion region, and the first source drift region and first drain drift region respectively, the first withstand voltage maintaining regions having a lower concentration than the first diffusion region.

Semiconductor devices include a semiconductor substrate containing a source region and a drain region, a gate structure supported by the semiconductor substrate between the source region and the drain region, a composite drift region in the semiconductor substrate, the composite drift region extending laterally from the drain region to at least an edge of the gate structure, the composite drift region including dopant having a first conductivity type, wherein at least a portion of the dopant is buried beneath the drain region at a depth exceeding an ion implantation range, and a well region in the semiconductor substrate. The well region has a second conductivity type and is configured to form a channel therein under the gate structure during operation. Methods for the fabrication of semiconductor devices are described.

A method comprises forming a buried layer over a substrate, forming an epitaxial layer over the buried layer, forming a first trench and a second trench in the buried layer and the epitaxial layer, wherein a width of the second trench is greater than a width of the first trench, depositing a dielectric layer in the first trench and the second trench, wherein the dielectric layer partially fills the second trench, removing the dielectric layer in the second trench and forming a first gate region in the first trench and a second gate region in the second trench.

A semiconductor device manufacturing method includes forming a silicon layer by epitaxial growth over a semiconductor substrate having a first area and a second area; forming a first gate oxide film by oxidizing the silicon layer; removing the first gate oxide film from the second area, while maintaining the first gate oxide film in the first area; thereafter, increasing a thickness of the first gate oxide film in the first area and simultaneously forming a second gate oxide film by oxidizing the silicon layer in the second area; and forming a first gate electrode and a second gate electrode over the first gate oxide film and the second gate oxide film, respectively, wherein after the formation of the first and second gate electrodes, the silicon layer in the first area is thicker than the silicon layer in the second area.

A semiconductor device includes at least one trench extending into a semiconductor substrate and lined with a gate dielectric layer; a dipole inducing layer covering a lowermost portion of the lined trench; a gate electrode covering the dipole inducing layer and filled in the lined trench; and doping regions, in the semiconductor substrate, separated from each other by the lined trench and separated from the dipole inducing layer.

A device and a method for forming a device are disclosed. The method includes providing a substrate prepared with a device region. A device well having second polarity type dopants is formed in the substrate. A threshold voltage (V.sub.T) implant is performed with a desired level of second polarity type dopants into the substrate. The V.sub.T implant forms a V.sub.T adjust region to obtain a desired V.sub.T of a transistor. A co-implantation with diffusion suppression material is performed to form a diffusion suppression (DS) region in the substrate. The DS region reduces or prevents segregation and out-diffusion of the V.sub.T implanted second polarity type dopants. A transistor of a first polarity type having a gate is formed in the device region. First and second diffusion regions are formed adjacent to sidewalls of the gate.

The present invention relates generally to integrated circuits and more particularly, to a structure and method of forming a hybrid circuit including a tunnel field-effect transistor (TFET) and a conventional field effect transistor (FET). Embodiments of the present invention include a hybrid amplifier which features a TFET common-source feeding a common-gate conventional FET (e.g. a MOSFET). A TFET gate may be electrically isolated from an output from a conventional FET. Thus, a high impedance input may be received by a TFET with a high-isolation output (i.e. low capacitance) at a conventional FET. A hybrid circuit amplifier including a TFET and a conventional FET may have a very high input impedance and a low miller capacitance.

A novel semiconductor transistor is presented. The semiconductor structure has a MOSFET like structure, with the difference that the device channel is formed in an intrinsic region, so as to effectively decrease the impurity and surface scattering phenomena deriving from a high doping profile typical of conventional MOS devices. Due to the presence of the un-doped channel region, the proposed structure greatly reduces Random Doping Fluctuation (RDF) phenomena decreasing the threshold voltage variation between different devices. In order to control the threshold voltage of the device, a heavily doped poly-silicon or metallic gate is used. However, differently from standard CMOS devices, a high work-function metallic material, or a heavily p-doped poly-silicon layer, is used for an n-channel device and a low work-function metallic material, or heavily n-doped poly-silicon layer, is used for a p-channel FET. Doped or insulating regions are used to increase the control on the channel conductivity.