In a silicon carbide semiconductor device, a trench penetrates a source region and a first gate region and reaches a drift layer. On an inner wall of the trench, a channel layer of a first conductivity-type is formed by epitaxial growth. On the channel layer, a second gate region of a second conductivity-type is formed. A first depressed portion is formed at an end portion of the trench to a position deeper than a thickness of the source region so as to remove the source region at the end portion of the trench. A corner portion of the first depressed portion is covered by a second conductivity-type layer.

A source region of a MOSFET includes a source contact region connected to a source electrode, a source extension region adjacent to a channel region of a well region, and a source resistance control region provided between the source extension region and the source contact region. The source resistance control region includes a low concentration source resistance control region which has an impurity concentration lower than that of the source contact region or the source extension region and a high concentration source resistance control region which is formed between the well region and the low concentration source resistance control region and has an impurity concentration higher than that of the low concentration source resistance control region.

The method for preventing epitaxial growth in a semiconductor device begins with cutting a set of long fins into a set of fins of a FinFET structure, the set of fins having respective cut faces of a set of cut faces located at respective fin ends of a set of fin ends. A photoresist layer is patterned over the set of fin ends of the set of fins of the FinFET structure. The photoresist pattern over the set of fin ends differs from the photoresist pattern over other areas of the FinFET structure as the photoresist pattern over the set of fin ends protects the first dielectric material at the set of fin ends. A set of dielectric blocks is formed at the set of fin ends, wherein each of the dielectric blocks covers at least one cut face. The set of dielectric blocks prevents epitaxial growth at the set of fin ends in a subsequent epitaxial growth step.

Provided is a semiconductor device comprising: a semiconductor substrate; a plurality of gate trench sections formed in the semiconductor substrate; and a plurality of emitter trench sections formed in the semiconductor substrate, one or more emitter trench sections provided in each region between adjacent gate trench sections of the plurality of gate trench sections, wherein the semiconductor device includes at least one of: pairs of gate trench sections in which at least two gate trench sections of the plurality of gate trench sections are connected; and a pair of emitter trench sections in which at least two emitter trench sections of the plurality of emitter trench sections are connected.

A semiconductor device includes a first drain region that is made primarily of SiC, a drift layer, a channel region, a first source region, a source electrode that is formed on the first source region, a second drain region that is connected to the first source region, a second source region that is formed separated from the second drain region, a first floating electrode that is connected to the second source region and to the channel region, first gate electrodes, and a second gate electrode that is connected to the first gate electrodes.

The semiconductor device of the present invention includes a first conductivity type semiconductor layer made of a wide bandgap semiconductor and a Schottky electrode formed to come into contact with a surface of the semiconductor layer, and has a threshold voltage V.sub.th of 0.3 V to 0.7 V and a leakage current J.sub.r of 110.sup.9 A/cm.sup.2 to 110.sup.4 A/cm.sup.2 in a rated voltage V.sub.R.

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 method of fabricating a semiconductor device is provided as follows. A channel layer is formed on a strain relaxed buffer (SRB) layer. A first etching process is performed on the channel layer and the SRB layer to form a plurality of trenches. The trenches penetrate through the channel layer and into the SRB layer to a first depth. First liners are formed on first sidewalls of the trenches having the first depth. The first liners cover the first sidewalls. A second etching process is performed on the SRB layer exposed through the trenches. The second etching process is performed on the SRB layer using a gas etchant having etch selectivity with respect to the first liners so that after the performing of the second etching process, the first liners remain on the first sidewalls.

A semiconductor structure includes a silicon carbide layer, which has a unit region and a termination region surrounding the unit region. A first guard ring structure is located in the termination region of the silicon carbide layer, and adjoins a top surface of the silicon carbide layer. The first guard ring structure may include at least one first guard ring well region. A second guard ring structure is located in the silicon carbide layer and below the first guard ring structure. The second guard ring structure may include at least one second guard ring well region, which corresponds to the at least one first guard ring well region in a vertical direction. A method for manufacturing the semiconductor structure is also provided.

An SiC semiconductor device includes an SiC semiconductor layer including an SiC monocrystal that is constituted of a hexagonal crystal and having a first main surface as a device surface facing a c-plane of the SiC monocrystal and has an off angle inclined with respect to the c-plane, a second main surface at a side opposite to the first main surface, and a side surface facing an a-plane of the SiC monocrystal and has an angle less than the off angle with respect to a normal to the first main surface when the normal is 0.