A semiconductor device includes a SiC semiconductor layer that has a carbon density of 1.0×10.sup.22 cm.sup.−3 or more, a SiO.sub.2 layer that is formed on the SiC semiconductor layer and that has a connection surface contiguous to the SiC semiconductor layer and a non-connection surface positioned on a side opposite to the connection surface, a carbon-density-decreasing region that is formed at a surface layer portion of the connection surface of the SiO.sub.2 layer and in which a carbon density gradually decreases toward the non-connection surface of the SiO.sub.2 layer, and a low carbon density region that is formed at a surface layer portion of the non-connection surface of the SiO.sub.2 layer and that has a carbon density of 1.0×10.sup.19 cm.sup.−3 or less.

FET designs that exhibit low leakage in the presence of the edge transistor phenomenon. Embodiments includes nFET designs in which the work function Φ.sub.MF of the gate structure overlying the edge transistors of the nFET is increased by forming extra P+ implant regions within at least a portion of the gate structure, thereby increasing the Vt of the edge transistors to a level that may exceed the Vt of the central conduction channel of the nFET. In some embodiments, the gate structure of the nFET is modified to increase or “flare” the effective channel length of the edge transistors relative to the length of the central conduction channel of the FET. Other methods of changing the work function Φ.sub.MF of the gate structure overlying the edge transistors are also disclosed. The methods may be adapted to fabricating pFETs by reversing or substituting material types.

Provided is a first vertical field effect transistor in which first source regions and first connection portions via which a first body region is connected to a first source electrode are disposed alternately and cyclically in a first direction in which first trenches extend. In a second direction orthogonal to the first direction, Lxm≤Lxr≤0.20 μm holds true where Lxm denotes a distance between adjacent first trenches and Lxr denotes the inner width of a first trench. The lengths of the first connection portions are in a convergence region in which the on-resistance of the vertical field effect transistor at the time when a voltage having a specification value is applied to first gate conductors to supply current having a specification value does not decrease noticeably even when the lengths of the first connection portions are made much shorter.

Provided is a compound semiconductor device that can suppress the deterioration of the element characteristics and a method of manufacturing a compound semiconductor device. The compound semiconductor device includes a laminated body constituted of a compound semiconductor and including a channel layer in which a first conductivity type carrier runs; a gate electrode provided on an upper surface side of the laminated body; a source electrode provided on the upper surface side of the laminated body; and a drain electrode provided on the upper surface side of the laminated body. The laminated body includes a second conductivity type first low resistance layer that is provided at a position facing the gate electrode and is in contact with the gate electrode, a first electric-field relaxation layer extended from the first low resistance layer toward a side of one of the source electrode and the drain electrode and configured to relax electric field concentration to the first low resistance layer, and a first amorphous layer covering a first side surface that is a side surface of the first electric-field relaxation layer and faces one of the source electrode and the drain electrode.

A semiconductor device and a method of making thereof are disclosed. The device includes a substrate heavily doped with a first conductivity type and an epitaxial layer lightly doped with the first conductivity type formed on the substrate. A buffer layer between the substrate and the epitaxial layer is doped with the first conductivity type at a doping level between that of the substrate and that of the epitaxial layer. A cell includes a body region doped with the second conductivity formed in the epitaxial layer. The second conductivity type is opposite the first conductivity type. The cell includes a source region doped with the first conductivity type and formed in at least the body region. The device further includes a short region doped with the second conductivity type formed in the epitaxial layer separated from source region of the cell by the body region of the cell wherein the short region is conductively coupled with the source region.

The application relates to a semiconductor die including a device in an active area of the die. The device includes a field electrode region formed in a field electrode trench extending vertically into a semiconductor body. The field electrode region includes a first and a second field electrode stacked vertically above each other in the field electrode trench. An edge termination structure laterally between the active area and a lateral edge region of the die includes a first and a second shield electrode arranged laterally consecutive between the active area and the lateral edge region to stepwise decrease an electrical potential between the edge region and the active area.

A semiconductor device and a method of fabricating same are disclosed. The semiconductor device includes: an SOI substrate including, stacked from the bottom upward, a lower substrate, a buried insulator layer and a semiconductor layer, wherein active regions surrounded by trench isolation structures are formed in the semiconductor layer; a gate electrode layer formed over the semiconductor layer, the gate electrode layer extending from active regions to trench isolation structures; and a source region and a drain region formed in the active regions that are on opposing sides of the gate electrode layer, wherein at least one end portion of the gate electrode layer laterally spans over interfaces of the active regions and the trench isolation structures toward the source region and/or the drain region. Thereby leakage at the interfaces of the active regions and the trench isolation structures can be reduced, resulting in improved performance of the semiconductor device.

A semiconductor device includes a semiconductor substrate of a first conductivity type, a body region of the first conductivity type, a source region of a second conductivity type, a drain region of the second conductivity type, a gate electrode, a drift region of the second conductivity type, an implanted oxide layer, and a semiconductor region of the first conductivity type. The semiconductor region is formed to extend in a direction along the top face of the semiconductor substrate. A first distance and a second distance are set so that an intensity of 0.35 MV/cm or less is observed in an electric field of a first region including the end portion of the drift region and in an electric field of a second region between the end of the semiconductor region and the drain region.

A method of manufacturing a semiconductor device capable of detecting occurrence of a Hi-K disappearance is provided. The method of manufacturing a semiconductor device includes a step of manufacturing a test pattern including a reference resistance, a gate leakage resistance through which a gate leakage current flows and connected in series with the reference resistance, and a step of measuring a change in voltage at a connection node between the reference resistance and the gate leakage resistance caused by the flow of the gate leakage current.

A semiconductor device includes a first region that contains a first conductive type impurity and is provided on a substrate, a second region that is provided in the first region and contains the first conductive type impurity at a higher concentration than the first region, a first structure that is provided on the substrate on one side of the second region in a first direction along the substrate and has a first sidewall at least on the second region side, a second structure that is provided on the substrate on the other side of the second region in the first direction and has a second sidewall at least on the second region side, and a contact that passes between the first and second sidewalls facing each other across the second region, extends to the second region, and is electrically connected to the second region.