Plural sessions of proton irradiation are performed by differing ranges from a substrate rear surface side. After first to fourth n-type layers of differing depths are formed, the protons are activated. Next, helium is irradiated to a position deeper than the ranges of the proton irradiation from the substrate rear surface, introducing lattice defects. When the amount of lattice defects is adjusted by heat treatment, protons not activated in a fourth n-type layer are diffused, forming a fifth n-type layer contacting an anode side of the fourth n-type layer and having a carrier concentration distribution that decreases toward the anode side by a more gradual slope than that of the fourth n-type layer. The fifth n-type layer that includes protons and helium and the first to fourth n-type layers that include protons constitute an n-type FS layer. Thus, a semiconductor device having improved reliability and lower cost may be provided.

A MOSFET having a stacked-gate super-junction design and novel termination structure. At least some illustrative embodiments of the device include a conductive (highly-doped with dopants of a first conductivity type) substrate with a lightly-doped epitaxial layer. The volume of the epitaxial layer is substantially filled with a charge compensation structure having vertical trenches forming intermediate mesas. The mesas are moderately doped via the trench sidewalls to have a second conductivity type, while the mesa tops are heavily-doped to have the first conductivity type. Sidewall layers are provided in the vertical trenches, the sidewall layers being a moderately-doped semiconductor of the first conductivity type. The shoulders of the sidewall layers are recessed below the mesa top to receive an overlying gate for controlling a channel between the mesa top and the sidewall layer. The mesa tops are coupled to a source electrode, while a drain electrode is provided on the back side of the substrate.

A MOSFET having a stacked-gate super-junction design and novel termination structure. At least some illustrative embodiments of the device include a conductive (highly-doped with dopants of a first conductivity type) substrate with a lightly-doped epitaxial layer. The volume of the epitaxial layer is substantially filled with a charge compensation structure having vertical trenches forming intermediate mesas. The mesas are moderately doped via the trench sidewalls to have a second conductivity type, while the mesa tops are heavily-doped to have the first conductivity type. Sidewall layers are provided in the vertical trenches, the sidewall layers being a moderately-doped semiconductor of the first conductivity type. The shoulders of the sidewall layers are recessed below the mesa top to receive an overlying gate for controlling a channel between the mesa top and the sidewall layer. The mesa tops are coupled to a source electrode, while a drain electrode is provided on the back side of the substrate.

A semiconductor device includes an anode doping region of a diode structure arranged in a semiconductor substrate. The anode doping region has a first conductivity type. The semiconductor device further includes a second conductivity type contact doping region having a second conductivity type. The second conductivity type contact doping region is arranged at a surface of the semiconductor substrate and surrounded in the semiconductor substrate by the anode doping region. The anode doping region includes a buried non-depletable portion. At least part of the buried non-depletable portion is located below the second conductivity type contact doping region in the semiconductor substrate.

A semiconductor device includes a JFET and a MOSFET cascode-connected to each other such that a source electrode of the JFET is connected to a drain electrode of the MOSFET. The JFET is configured such that a breakdown voltage between a gate layer and a body layer is set lower than a breakdown voltage of the MOSFET.

A silicon carbide crystal includes a seed layer, a bulk layer, and a stress buffering structure formed between the seed layer and the bulk layer. The seed layer, the bulk layer, and the stress buffering structure are each formed with a dopant that cycles between high and low dopant concentration. The stress buffering structure includes a plurality of stacked buffer layers and a transition layer over the buffer layers. The buffer layer closest to the seed layer has the same variation trend of the dopant concentration as the buffer layer closest to the transition layer, and the dopant concentration of the transition layer is equal to the dopant concentration of the seed layer.

A silicon carbide crystal includes a seed layer, a bulk layer, and a stress buffering structure formed between the seed layer and the bulk layer. The seed layer, the bulk layer, and the stress buffering structure are each formed with a dopant that cycles between high and low dopant concentration. The stress buffering structure includes a plurality of stacked buffer layers and a transition layer over the buffer layers. The buffer layer closest to the seed layer has the same variation trend of the dopant concentration as the buffer layer closest to the transition layer, and the dopant concentration of the transition layer is equal to the dopant concentration of the seed layer.

Provided is a semiconductor device comprising a semiconductor substrate, wherein the semiconductor substrate includes a hydrogen containing region including hydrogen, and the hydrogen containing region includes a high concentration region with a higher carrier concentration than a virtual carrier concentration determined based on a concentration of hydrogen included and an activation ratio of hydrogen. The semiconductor substrate includes an N type drift region, an N type emitter region that has a higher carrier concentration than that in the drift region, a P type base region, a P type collector region provided to be in contact with a lower surface of the semiconductor substrate, and an N type buffer region that is provided between the collector region and the drift region, and has a higher carrier concentration than that in the drift region, and the hydrogen containing region is included in the buffer region.

Provided is a semiconductor device comprising a semiconductor substrate, wherein the semiconductor substrate includes a hydrogen containing region including hydrogen, and the hydrogen containing region includes a high concentration region with a higher carrier concentration than a virtual carrier concentration determined based on a concentration of hydrogen included and an activation ratio of hydrogen. The semiconductor substrate includes an N type drift region, an N type emitter region that has a higher carrier concentration than that in the drift region, a P type base region, a P type collector region provided to be in contact with a lower surface of the semiconductor substrate, and an N type buffer region that is provided between the collector region and the drift region, and has a higher carrier concentration than that in the drift region, and the hydrogen containing region is included in the buffer region.

Provided is a semiconductor device including: a semiconductor substrate provided with an active portion and an edge termination structure portion surrounding the active portion; an interlayer dielectric film provided above the semiconductor substrate; a protective film provided above the interlayer dielectric film; and a protruding portion provided farther from the active portion than the edge termination structure portion and protruding further than the interlayer dielectric film. The protruding portion is not covered with the protective film. The protective film is provided closer to the active portion than the protruding portion.