A semiconductor device and a method for producing thereof is provided. The semiconductor device includes a plurality of device cells, each comprising a body region, a source region, and a gate electrode adjacent to the body region and dielectrically insulated from the body region by a gate dielectric; and an electrically conductive gate layer comprising the gate electrodes or electrically connected to the gate electrodes of the plurality of device cells. The gate layer is electrically connected to a gate conductor and includes at least one of an increased resistance region and a decreased resistance region.

A semiconductor device includes a drift region of a device structure arranged in a semiconductor layer. The drift region includes at least one first drift region portion and at least one second drift region portion. A majority of dopants within the first drift region portion are a first species of dopants having a diffusivity less than a diffusivity of phosphor within the semiconductor layer. Further, a majority of &pants within the second drift region portion are a second species of dopants. Additionally, the semiconductor device includes a trench extending from a surface of the semiconductor layer into the semiconductor layer. A vertical distance of a border between the first drift region portion and the second drift region portion to the surface of the semiconductor layer is larger than 0.5 times a maximal depth of the trench and less than 1.5 times the maximal depth of the trench.

Trench MOSFET with self-aligned body contact with spacer. In accordance with an embodiment of the present invention, a semiconductor device includes a semiconductor substrate, and at least two gate trenches formed in the semiconductor substrate. Each of the trenches comprises a gate electrode. The semiconductor device also includes a body contact trench formed in the semiconductor substrate between the gate trenches. The body contact trench has a lower width at the bottom of the body contact trench and an ohmic body contact implant beneath the body contact trench. The horizontal extent of the ohmic body contact implant is at least the lower width of the body contact trench.

A semiconductor device having a plurality of transistors includes a termination area that features a transistor with an asymmetric gate.

Forming a semiconductor device on a semiconductor substrate having a substrate top surface includes: forming a gate trench extending from the substrate top surface into the semiconductor substrate; forming a gate electrode in the gate trench; forming a curved sidewall portion along at least a portion of a sidewall of the gate trench; forming a body region adjacent to the gate trench; forming a source region embedded in the body region, including disposing source material in a region that is along at least a part of the curved sidewall portion; forming a gate top dielectric layer over the gate electrode and having a top side that is below at least a portion of the source region; and forming a metal layer over at least a portion of a gate trench opening and at least a portion of the source region.

A semiconductor device that has a source region, a channel region, and a drain region disposed in order from a surface of the semiconductor device in a thickness direction of a semiconductor substrate. The semiconductor device includes a gate insulating film having an extended portion that covers the surface of the semiconductor substrate outside of a gate trench and a top surface of a polysilicon gate. A connection gate trench branches from the gate trench, and joins a contact gate trench which is wider than the gate trench and the connection gate trench. The polysilicon gate is embedded in the connection gate trench and the contact gate, and extends from the gate trench to the contact gate trench through the connection gate trench. The gate contact groove is formed in the polysilicon gate within the contact gate trench.

A semiconductor device has an FET of a trench-gate structure obtained by disposing a conductive layer, which will be a gate, in a trench extended in the main surface of a semiconductor substrate, wherein the upper surface of the trench-gate conductive layer is formed equal to or higher than the main surface of the semiconductor substrate. The conductive layer of the trench gate is formed to have a substantially flat or concave upper surface and the upper surface is formed equal to or higher than the main surface of the semiconductor substrate. After etching of the semiconductor substrate to form the upper surface of the conductive layer of the trench gate, a channel region and a source region are formed by ion implantation so that the semiconductor device is free from occurrence of a source offset.

There is provided a trench-gate type semiconductor device that can prevent breakdown of a gate insulating film caused by a displacement current flowing into a protective diffusion layer at a portion of a trench underlying a gate electrode at a turn-off time and simultaneously improves a current density by narrowing a cell pitch. The semiconductor device has a gate electrode 7 embedded into a trench 5 penetrating a base region 3. The gate electrode 7 is disposed into a lattice shape in a planar view, and a protective diffusion layer 13 is formed in a drift layer 2a at the portion underlying thereof. At least one of blocks divided by the gate electrode 7 is a protective contact region 20 on which the trench 5 is entirely formed. A protective contact 21 for connecting the protective diffusion layer 13 at a bottom portion of the trench 5 and a source electrode 9 is disposed on the protective contact region 20.

An SiC semiconductor device has a p type region including a low concentration region and a high concentration region filled in a trench formed in a cell region. A p type column is provided by the low concentration region, and a p.sup.+ type deep layer is provided by the high concentration region. Thus, since a SJ structure can be made by the p type column and the n type column provided by the n type drift layer, an on-state resistance can be reduced. As a drain potential can be blocked by the p.sup.+ type deep layer, at turnoff, an electric field applied to the gate insulation film can be alleviated and thus breakage of the gate insulation film can be restricted. Therefore, the SiC semiconductor device can realize the reduction of the on-state resistance and the restriction of breakage of the gate insulation film.

A MOS transistor, in particular a vertical channel transistor, includes a semiconductor body housing a body region, a source region, a drain electrode and gate electrodes. The gate electrodes extend in corresponding recesses which are symmetrical with respect to an axis of symmetry of the semiconductor body. The transistor also has spacers which are also symmetrical with respect to the axis of symmetry. A source electrode extends in electrical contact with the source region at a surface portion of the semiconductor body surrounded by the spacers and is in particular adjacent to the spacers. During manufacture the spacers are used to form in an auto-aligning way the source electrode which is symmetrical with respect to the axis of symmetry and equidistant from the gate electrodes.