Abstract: A power semiconductor device includes semiconductor layer structure comprising a semiconductor drift region of a first conductivity type and an edge termination region comprising a plurality of guard rings of a second conductivity type. The guard rings extend into a surface of the semiconductor drift region. The guard rings respectively comprise a first portion adjacent the surface and a second portion spaced from the surface, where the first portion is wider than the second portion. Related devices and fabrication methods are also discussed.

Abstract: A semiconductor device includes a semiconductor layer structure and a gate formed in a gate trench in the semiconductor layer structure. The gate trench has a bottom surface comprising a first portion at a first level and a second portion at a second level, different from the first level. A method of forming a semiconductor device includes providing a semiconductor layer structure, etching a first gate trench into the semiconductor layer structure, etching a second gate trench into the semiconductor layer structure, and performing an ion implantation into a bottom surface of the second gate trench. The second gate trench is deeper than the first gate trench, and at least a portion of the second gate trench is connected to the first gate trench.

Abstract: A semiconductor device comprises a semiconductor layer structure that has a gate trench therein and a source metallization layer on the semiconductor layer structure. The semiconductor layer structure comprises a drift region having a first conductivity type, a trench shield that has a second conductivity type, the trench shield positioned underneath the gate trench, and a trench shield connection pattern that has the second conductivity type, the trench shield connection pattern electrically connecting the trench shield to the source metallization layer, where the trench shield connection pattern extends deeper into the semiconductor layer structure than the trench shield.

Abstract: A semiconductor device such as a MOSFET or IGBT comprises a semiconductor layer structure that comprises a drift layer and a plurality of well regions in the drift layer, the well regions extending to an upper surface of the semiconductor layer structure. The drift layer comprises a first region and a second region that has a higher peak doping concentration type than the first region. The second region of the drift layer comprises an implanted region and extends between adjacent well regions and underneath the well regions. The second region of the drift layer also comprises a plurality of openings, and the first region of the drift layer is exposed through the openings in the second region of the drift layer.

Abstract: A semiconductor device such as a MOSFET or IGBT comprises a semiconductor layer structure that comprises a drift layer and a plurality of well regions in the drift layer, the well regions extending to an upper surface of the semiconductor layer structure. The drift layer comprises a first region and a second region that has a higher peak doping concentration type than the first region. The second region of the drift layer comprises an implanted region and extends between adjacent well regions and underneath the well regions. The second region of the drift layer also comprises a plurality of openings, and the first region of the drift layer is exposed through the openings in the second region of the drift layer.

Abstract: A semiconductor device comprises a silicon carbide based semiconductor layer structure and a first gate trench extending into an upper portion of the semiconductor layer structure. The semiconductor layer structure comprises a drift region having a first conductivity type, a well layer having a second conductivity type, and a support shield having the second conductivity type. A width of a first segment of the support shield that is deeper in the semiconductor layer structure than the well layer and less deep in the semiconductor layer structure than a bottom of the first gate trench decreases with increasing distance from the well region.

Abstract: A wide band-gap semiconductor layer structure is provided that comprises a drift region having a first conductivity type and a plurality of source regions having the first conductivity type on the drift region. A plurality of trenches are provided in an upper surface of the wide band-gap semiconductor layer structure. Second conductivity type dopants are implanted into the wide band-gap semiconductor layer structure to simultaneously form well regions underneath the source regions and trench shielding regions underneath the trenches, the well regions and the trench shielding regions each having a second conductivity type.

Abstract: A semiconductor device comprises a silicon carbide based semiconductor layer structure that includes a drift layer having a first conductivity type, a gate trench that extends to a first depth into an upper surface of the semiconductor layer structure, a gate electrode in the gate trench, a support shield trench that extends to a second depth into the upper surface of the semiconductor layer structure, where the second depth is less than the first depth, and a source metallization layer on the upper surface of the semiconductor layer structure and extending into the support shield trench.

Abstract: A semiconductor die includes a drift region, an active region in the drift region, and an edge termination region surrounding the active region in the drift region. The drift region has a first doping type. The edge termination region includes a charge compensation region, a number of guard rings, and a counter doping region. The charge compensation region is in the drift region and has a second doping type that is opposite the first doping type. The guard rings are in the charge compensation region, have the second doping type, and a doping concentration that is greater than a doping concentration of the charge compensation region. The counter doping region is in the drift region and overlaps at least a portion of the charge compensation region. The counter doping region has the first doping type.

Abstract: A semiconductor device comprises a semiconductor layer structure comprising a drift region having a first conductivity type, a plurality of continuous first gate trenches in the semiconductor layer structure, and a plurality of second gate trenches in the semiconductor layer structure, the second gate trenches intersecting the first gate trenches.

Abstract: A semiconductor device includes a semiconductor layer structure having a drift region of a first conductivity type and a well region of a second conductivity type above the drift region. A gate is provided on the semiconductor layer structure adjacent the well region. A buried shielding structure of the second conductivity type is provided under the well region and separated from the well region by a portion of the drift region. Related devices and fabrication methods are also discussed.

Abstract: An example power semiconductor device includes a silicon carbide semiconductor structure. The example power semiconductor device includes at least one heterodoped layer in the silicon carbide semiconductor structure. In some implementations, the heterodoped layer includes a first layer having a first dopant concentration of a first conductivity type in a range of about 1×1017/cm3 to about 2×1021/cm3. The heterodoped layer includes a second layer having a second dopant concentration of the first conductivity type that is less than the first dopant concentration of the first layer. In some examples, the second layer may be undoped.

Abstract: An example power semiconductor device includes a silicon carbide semiconductor structure. The example power semiconductor device includes at least one heterodoped layer in the silicon carbide semiconductor structure. In some implementations, the heterodoped layer includes a first layer having a first dopant concentration of a first conductivity type in a range of about 1×1017/cm3 to about 2×1021/cm3. The heterodoped layer includes a second layer having a second dopant concentration of the first conductivity type that is less than the first dopant concentration of the first layer. The semiconductor structure includes a drift region, wherein the drift region has a third dopant concentration of the first conductivity type. The third dopant concentration is less than the first dopant concentration.

Abstract: A wide band-gap semiconductor layer structure is provided that comprises a drift region having a first conductivity type and a plurality of source regions having the first conductivity type on the drift region. A plurality of trenches are provided in an upper surface of the wide band-gap semiconductor layer structure. Second conductivity type dopants are implanted into the wide band-gap semiconductor layer structure to simultaneously form well regions underneath the source regions and trench shielding regions underneath the trenches, the well regions and the trench shielding regions each having a second conductivity type.

Abstract: A semiconductor device includes a semiconductor layer structure comprising a gate trench formed in an upper surface thereof, a gate finger in the gate trench, a supplemental dielectric layer on an upper surface of the gate finger and vertically overlaps the gate trench, and a gate connector on an upper surface of the supplemental dielectric layer and on an upper surface of the gate finger.

Abstract: A semiconductor device comprises a semiconductor layer structure comprising a drift region having a first conductivity type, a first gate electrode on the semiconductor layer structure that extends along a first longitudinal axis, a second gate electrode on the semiconductor layer structure that extends along a second longitudinal axis, and a first ohmic line that extends continuously in the semiconductor layer structure along a first transverse axis. The first and second longitudinal axes cross the first transverse axis when the semiconductor device is viewed from above.

Abstract: A semiconductor device comprises a semiconductor layer structure comprising a drift region having a first conductivity type, a first gate electrode on the semiconductor layer structure that extends along a first longitudinal axis, a second gate electrode on the semiconductor layer structure that extends along a second longitudinal axis, and a first ohmic line that extends continuously in the semiconductor layer structure along a first transverse axis. The first and second longitudinal axes cross the first transverse axis when the semiconductor device is viewed from above.

Abstract: A method of forming ohmic contacts on a semiconductor structure having a p-type region and an n-type region includes depositing a first metal on the n-type region, annealing the structure at a first contact anneal temperature to form a first ohmic contact on the n-type region, depositing a second metal on the first ohmic contact and on the p-type region, and annealing the structure at a second contact anneal temperature, less than the first contact anneal temperature, to form a second ohmic contact on the p-type region.

Abstract: A vertical semiconductor device includes a drift layer, a mesa on the drift layer, and a trench adjacent to the mesa. The mesa includes a mesa sidewall, a channel layer and a source layer on the channel layer. The channel layer is between the source layer and the drift layer. A sidewall gate region in the mesa adjacent the mesa sidewall and a sidewall channel region is in the channel layer adjacent the sidewall gate region. The channel layer is doped with first conductivity type dopants and has a first doping concentration. The sidewall channel region is doped with first conductivity type dopants and has a second doping concentration that is greater than the first doping concentration. The sidewall gate region extends deeper toward the drift layer than the sidewall channel region.

Abstract: A power semiconductor device includes a semiconductor structure having a first side, a second side, and a drift region of a first conductivity type therebetween, and implanted regions of a second conductivity type in the semiconductor structure adjacent the first side of the semiconductor structure. The implanted regions include first portions of a first material and second portions of a second material, with the second portions positioned between the first portions and the second side. The second material has an atomic weight that is lighter than that of the first material. Related fabrication methods are also discussed.