A silicon carbide semiconductor device includes a silicon carbide substrate having first and second main surfaces and including an electric field relaxation region and a connection region. A gate trench provided in the first main surface is defined by side surfaces and a bottom surface. The electric field relaxation region is a second conductivity type and provided between the bottom surface and the second main surface, and the connection region is the second conductivity type and electrically connects a contact region including first and second regions to the electric field relaxation region. In plan view, the gate trench and the electric field relaxation region are located on a virtual straight line. The first region is in contact with the connection region on the virtual straight line, and the second region is provided on a position where the source region is sandwiched between the gate trench and the second region.

A method for forming a semiconductor wafer includes providing a substrate wafer, in which the substrate wafer has a bow value that is non-zero and has a first portion, the first portion has a first surface and a second surface opposite to the first surface, and the first surface is concave. The method further includes performing a first ion implantation process to the substrate wafer, such that the first surface of the first portion has a first implantation region, and the bow value of the substrate wafer is closer to zero after performing the first ion implantation process than before performing the first ion implantation process. The method further includes depositing an epitaxial layer on the substrate wafer after performing the first ion implantation process.

A vertical conduction MOSFET device includes a body of silicon carbide, which has a first type of conductivity and a face. A superficial body region of a second type of conductivity has a first doping level and extends into the body to a first depth, and has a first width. A source region of the first type of conductivity extends into the superficial body region to a second depth, and has a second width. The second depth is smaller than the first depth and the second width is smaller than the first width. A deep body region of the second type of conductivity has a second doping level and extends into the body, at a distance from the face of the body and in direct electrical contact with the superficial body region, and the second doping level is higher than the first doping level.

In an embodiment, a semiconductor device is provided that includes: a vertical power FET configured to switch a load current and provide a channel of a first conductivity type; and a lateral FET configured to drive the vertical power FET and provide a channel of a second conductivity type opposing the first conductivity type. The vertical power FET and the lateral FET are monolithically integrated into a semiconductor substrate of the first conductivity type and a drain of the lateral FET is electrically coupled to a gate of the vertical power FET.

The present disclosure generally relates to semiconductor processing for forming a semiconductor device. In an example, semiconductor device includes a semiconductor substrate, a nitride structure, and an oxide layer. The nitride structure is over the semiconductor substrate. The oxide layer is on the nitride structure. The semiconductor substrate includes an implanted doped region laterally proximate the nitride structure and the oxide layer. In another example, a nitride structure is formed over a semiconductor substrate. An oxide layer is formed on the nitride structure. A photoresist is formed over the semiconductor substrate. The photoresist has an opening exposing at least a portion of the oxide layer on the nitride structure. An implantation is performed using the photoresist to form an implanted doped region in the semiconductor substrate.

According to some embodiments, a method for manufacturing a semiconductor device is provided. One or more first implantation processes are performed to form an implanted region, of a first conductivity type, in a semiconductor body. A trench is formed in the semiconductor body. After forming the trench, a second implantation process is performed to form a current spread region, of a second conductivity type, in the semiconductor body. The second implantation process includes implanting first dopants, through a top surface of the semiconductor body, to form a first portion of the current spread region, and implanting second dopants, through a bottom of the trench, to form a second portion of the current spread region. A gate structure is formed in the trench. A vertical position of the first portion of the current spread region matches a vertical position of the gate structure. The second portion of the current spread region underlies the gate structure.

A manufacturing method of a semiconductor device includes the following steps. A base region is formed in a substrate. A protective layer is formed on the substrate and covers the base region. First and second sacrificial layers are formed on the substrate and cover the protective layer. A source region, a well region, and a junction field effect transistor (JFET) region are formed in the substrate. When the source region, the well region, and the JFET region are formed in sequence, the source region and the well region are formed by the first sacrificial layer, and the JFET region is formed by the second sacrificial layer. When the JFET region, the well region, and the source region are formed in sequence, the JFET region is formed by the first sacrificial layer, and the well region and the source region are formed by the second sacrificial layer.

There is provided a diode including an anode electrode provided on a side of a front surface of a semiconductor substrate, an interlayer dielectric film disposed between the semiconductor substrate and the anode electrode, a first anode region of a first conductivity type provided on the front surface of the semiconductor substrate, a second anode region of a second conductivity type, which is different from the first conductivity type, provided on the front surface of the semiconductor substrate, a first contact hole provided in the interlayer dielectric film, causing the anode electrode to be in Schottky contact with the first anode region, and a second contact hole provided in the interlayer dielectric film and different from the first contact hole, causing the anode electrode to be in ohmic contact with the second anode region.

A semiconductor device includes a semiconductor substrate, a base region, an emitter region, a collector region, and an element isolation insulating film. The semiconductor substrate has a main surface. The base region has a first conductivity type and is disposed in a surface layer of the semiconductor substrate that is close to the main surface. The emitter region has a second conductivity type and is disposed in a surface layer of the base region. The collector region has the second conductivity type and is disposed at a portion in the surface layer of the semiconductor substrate apart from the emitter region. The element isolation insulating film is disposed on the main surface, and has a thermal oxide film being in contact with a junction interface between the base region and the emitter region.

A transistor device ac includes a semiconductor epitaxial layer structure including a channel layer and a barrier layer on the channel layer, wherein the barrier layer has a higher bandgap than the channel layer, a source contact and a drain contact on the barrier layer, and a gate contact on the barrier layer between source contact and the drain contact. The device further includes a plurality of selective modified access regions at an upper surface of the barrier layer opposite the channel layer. The selective modified access regions include a material having a lower surface barrier height than the barrier layer, and the plurality of selective modified access regions are spaced apart on the barrier layer along a length of the gate contact.