A trench gate silicon carbide metal oxide semiconductor field effect transistor (MOSFET) device and a fabrication method thereof. A second conductive heavily doped layer at the bottom corner of a trench gate is electrically connected to a second conductive heavily doped layer on another side edge of the trench gate through a layout design, which ensures a ground potential during voltage blocking state. This design protects the insulating layer in the trench gate and the Schottky contact in a junction barrier Schottky (JBS) diode, thereby enhancing device reliability. Moreover, in a diode operating mode, P+ on the left and right sides of the trench gate are connected to a positive potential. When the P+/N? junction is activated, the conductivity modulation can be implemented through hole injection, thereby improving the device's ability to withstand surge current impacts.

A power semiconductor device includes: a semiconductor body having a first surface and a mesa portion that includes a surface part of the first surface and a body region; at least two trenches extending from the first surface into the semiconductor body along a vertical direction, each trench including a trench electrode and trench insulator insulating the trench electrode from the semiconductor body, the mesa portion being laterally confined by the trenches in a first vertical cross-section along a first lateral direction; and a contact plug in contact with the body region. The contact plug and trench electrode of a first trench laterally overlap at least partially in the first vertical cross-section. A protection structure having a portion arranged within the first trench is arranged between the contact plug and trench electrode of the first trench. The protection structure may be an electrically insulation structure or a protective device structure.

Semiconductor devices, and in particular protection structures for semiconductor devices that include sensor arrangements are disclosed. A semiconductor device may include a sensor region, for example a current sensor region that occupies a portion of an overall active area of the device. The current sensor region may be configured to provide monitoring of device load currents during operation. Semiconductor devices according to the present disclosure include one or more protection structures that are configured to allow the semiconductor devices to withstand transient voltage events without device failure. A protection structure may include an insulating layer that is provided in a transition region between a device region and the sensor region of the semiconductor device. In the example of an insulated gate semiconductor device, the insulating layer of the protection structure may include a material with a greater breakdown voltage than a breakdown voltage of a gate insulating layer.

In this patent application, a new Metal Oxide Semiconductor MOS planar cell design concept is proposed. The inventive power semiconductor includes a planar cell forming a horizontal channel and a plurality of trenches, which are arranged orthogonally to the plane of the planar cells. A second p base layer is introduced which extends perpendicularly deeper than the source region and laterally to the same distance/extent as the source region. Therefore, a vertical channel is prevented from forming in the trench regions while allowing the horizontal channels to form. This is extremely important in order to avoid significant issues (i.e. shifts in Vth) encountered in prior art IGBT designs. The new cell concept adopts planar MOS channel and Trench technology in a single MOS cell structure. The new design offers a wide range of advantages both in terms of performance (reduced losses, improved controllability and reliability), and processability (narrow mesa design rules, reliable planar process compatibility) and can be applied to both IGBTs and MOSFETs based on silicon or wide bandgap materials such as Silicon Carbide SiC. Furthermore, the device is easy to manufacture, because the inventive design can be manufactured based on a self-aligned process with minimum number of masks, with the potential of additionally applying enhancement layers and/or reverse conducting type of structures.

In this patent application, a new Metal Oxide Semiconductor MOS planar cell design concept is proposed. The inventive power semiconductor includes a planar cell forming a horizontal channel and a plurality of trenches, which are arranged orthogonally to the plane of the planar cells. A second p base layer is introduced which extends perpendicularly deeper than the source region and laterally to the same distance/extent as the source region. Therefore, a vertical channel is prevented from forming in the trench regions while allowing the horizontal channels to form. This is extremely important in order to avoid significant issues (i.e. shifts in Vth) encountered in prior art IGBT designs. The new cell concept adopts planar MOS channel and Trench technology in a single MOS cell structure. The new design offers a wide range of advantages both in terms of performance (reduced losses, improved controllability and reliability), and processability (narrow mesa design rules, reliable planar process compatibility) and can be applied to both IGBTs and MOSFETs based on silicon or wide bandgap materials such as Silicon Carbide SiC. Furthermore, the device is easy to manufacture, because the inventive design can be manufactured based on a self-aligned process with minimum number of masks, with the potential of additionally applying enhancement layers and/or reverse conducting type of structures.

A semiconductor device includes an N+ type substrate, an N type layer disposed on a first surface of the N+ type substrate and having a trench opened to a surface opposite to the surface facing the N+ type substrate, a P type region disposed in the N type layer and disposed on a side surface of the trench, a gate electrode disposed in the trench, and a source electrode and a drain electrode insulated from the gate electrode. The N type layer includes a P type shield region covering a bottom surface and an edge of the trench.

A semiconductor device includes an N+ type substrate, an N type layer disposed on a first surface of the N+ type substrate and having a trench opened to a surface opposite to the surface facing the N+ type substrate, a P type region disposed in the N type layer and disposed on a side surface of the trench, a gate electrode disposed in the trench, and a source electrode and a drain electrode insulated from the gate electrode. The N type layer includes a P type shield region covering a bottom surface and an edge of the trench.

A silicon carbide (SiC) planar transistor device includes a SiC semiconductor substrate of a first charge type, a SiC epitaxial layer of the first charge type formed at a top surface of the SiC semiconductor substrate, a source structure of the first charge type formed at a top surface of the SiC epitaxial layer, a drain structure of the first charge type formed at a bottom surface of the SiC semiconductor substrate, a gate structure comprising a gate runner and a gate dielectric that covers at least part of the source structure and the gate runner, and a channel region of a second charge type located in vertical direction below the gate structure and adjacent to the source structure. The channel can be formed by performing a plurality of implantation steps so that the channel region comprises a first region and a second region.

A semiconductor device includes an IGBT in an IGBT portion of a semiconductor body and a diode in a diode portion of the semiconductor body. The diode includes an anode region of a first conductivity type and confined by diode trenches along a first lateral direction. Each of the diode trenches includes a diode trench electrode and a diode trench dielectric. A first contact groove extends into the anode region along a vertical direction from the first surface of the semiconductor body. An anode contact region of the first conductivity type adjoins a bottom side of the first contact groove. A cathode contact region of a second conductivity type adjoins a second surface of the semiconductor body opposite to the first surface. The IGBT includes a gate trench including a gate electrode and a gate dielectric, a source region, an emitter electrode, a drift region, and a second contact groove.

A method of manufacturing a vertical power semiconductor device includes forming a drift region in a semiconductor body having a first main surface and a second main surface opposite to the first main surface along a vertical direction, the drift region including platinum atoms, and forming a field stop region in the semiconductor body between the drift region and the second main surface, the field stop region including a plurality of impurity peaks, wherein a first impurity peak of the plurality of impurity peaks is set a larger concentration than a second impurity peak of the plurality of impurity peaks, wherein the first impurity peak includes hydrogen and the second impurity peak includes helium.