Provided are a power device having an improved field stop layer and a method of manufacturing the same. The power device includes: a first field stop layer formed of a semiconductor substrate and of a first conductive type; a second field stop layer formed on the first field stop layer and of the first conductive type, the second field stop layer having a region with an impurity concentration higher than the first field stop layer; a drift region formed on the second field stop layer and of the first conductive type, the drift region having an impurity concentration lower than the first field stop layer; a plurality of power device cells formed on the drift region; and a collector region formed below the first field stop layer, wherein the second field stop layer includes a first region having a first impurity concentration and a second region having a second impurity concentration higher than the first impurity concentration.

A Tunnel Field-Effect Transistor comprising a source-channel-drain structure, the source-channel-drain structure comprising a source region doped with a dopant element having a first dopant type and a first doping concentration; a drain region doped with a dopant element having a second dopant type opposite compared to the first dopant type, and a second doping concentration, a channel region situated between the source region and the drain region and having an intrinsic doping concentration, or lowly doped concentration being lower than the doping concentration of the source and drain regions, a gate stack comprising a gate electrode on a gate dielectric layer, the gate stack covering at least part of the channel region and extending at the source side up to at least an interface between the source region and the channel region, a drain extension region in the channel region or on top thereof, the drain extension region being formed from a material suitable for creating, and having a length/thickness ratio such that, in use, it creates a charged layer, in the OFF-state of the TFET, with a charge opposite to the charge of the majority carriers in the drain region.

A method of manufacturing a semiconductor device includes a semiconductor region forming process, a cleaning process, a surface roughness uniformizing process, and an electrode forming process. As the semiconductor region forming process, semiconductor regions are formed such that a plurality of semiconductor regions with different ion injection amounts are exposed on one principal surface of a semiconductor substrate. As the cleaning process, after the semiconductor region forming process, a cleaning using hydrofluoric acid is performed on the one principal surface of the semiconductor substrate. As the surface roughness uniformizing process, after the cleaning process, the surface roughness of the one principal surface of the semiconductor substrate is uniformized. As the electrode forming process, after the surface roughness uniformizing process, electrodes are formed on the one principal surface of the semiconductor substrate.

A semiconductor substrate having a first main surface and a transistor cell includes a drift region, a body region between the drift region and the first main surface, an active trench at the first main surface extending into the drift region, a gate insulating layer at sidewalls and a bottom side of the active trench, a gate conductive layer in the active trench, a source region in the body region, and adjacent to the active trench, a body trench at the first main surface extending into the drift region, the body trench being adjacent to the body region and to the drift region, an insulating layer at sidewalls and at a bottom side of the body trench, the insulating layer being asymmetric with respect to an axis extending perpendicular to the first main surface at a center of the body trench, and a conductive layer in the body trench.

A semiconductor device structure is provided. The semiconductor device structure includes a substrate having a top surface. The semiconductor device structure includes a first pillar structure over the substrate. The first pillar structure includes a first heavily n-doped layer, a first p-doped layer, an n-doped layer, and a first heavily p-doped layer, which are sequentially stacked together. The first pillar structure extends in a direction away from the substrate.

A reverse blocking semiconductor device is manufactured by introducing impurities of a first conductivity type into a semiconductor substrate of the first conductivity type through a process surface to obtain a process layer extending into the semiconductor substrate up to a first depth, and introducing impurities of a second, complementary conductivity type into the semiconductor substrate through openings of an impurity mask provided on the process surface to obtain emitter zones of the second conductivity type extending up to a second depth deeper than the first depth and channels of the first conductivity type between the emitter zones. Exposed portions of the process layer are removed above the emitter zones.

A semiconductor device includes an IGBT region with a bottom-body region on a front surface side of an IGBT drift region, an IGBT barrier region on a front surface side of the bottom-body region, and a top-body region on a front surface side of the IGBT barrier region. A diode region is include with a bottom-anode region on a front surface side of the diode drift region, a diode barrier region on a front surface side of the bottom-anode region, a top-anode region on a front surface side of the diode barrier region, and a pillar region extending from the front surface of the semiconductor substrate, piercing the top-anode region, and reaching the diode barrier region, and connected to the front surface electrode and the diode barrier region. An impurity concentration of the top-body region is lower than an impurity concentration of the bottom-anode region.

According to one embodiment, a semiconductor device includes a semiconductor substrate in which a recess is provided on a back surface thereof, and a shape of the recess is reflected on a surface of a metal film which is also provided on the back surface of the semiconductor substrate.

A method for manufacturing a semiconductor device having an SiC-IGBT and an SiC-MOSFET in a single semiconductor chip, including forming a second conductive-type SiC base layer on a substrate, and selectively implanting first and second conductive-type impurities into surfaces of the substrate and base layer to form a collector region, a channel region in a surficial portion of the SiC base layer, and an emitter region in a surficial portion of the channel region, the emitter region serving also as a source region of the SiC-MOSFET.

An IGBT includes an n-type drift layer, a p-type base layer and an n-type emitter layer formed on an upper surface of the n-type drift layer, and a p-type collector layer on a lower surface of the n-type drift layer. A FWD includes the n-type drift layer, a p-type anode layer formed on the upper surface of the n-type drift layer and an n-type cathode layer formed on the lower surface of the n-type drift layer. A p-type well is formed on the upper surface of the n-type drift layer in a wiring region and a termination region. A wiring is formed on the p-type well in the wiring region. The p-type well has a higher impurity concentration and is deeper than the p-type anode layer. The p-type well is not formed directly above the n-type cathode layer and is separate from a region directly above the n-type cathode layer.