A multi-trench super junction IGBT device includes a metallization collector, a P-type substrate, a first N-type epitaxial layer located above the P-type substrate and a second N-type epitaxial layer located above the first N-type epitaxial layer. The second N-type epitaxial layer includes at least a first dummy MOS cell unit and a MOS cell unit, wherein the first dummy MOS cell unit includes a trench formed by reactive ion etching, a thermally grown gate oxide layer provided inside the trench and deposited heavily doped polysilicon located in the gate oxide layer.

According to an aspect of the present disclosure, a semiconductor device includes a substrate including an IGBT region, and a diode region, a surface electrode provided on a top surface of the substrate and a back surface electrode provided on a back surface on an opposite side to the top surface of the substrate, wherein the diode region includes a first portion formed to be thinner than the IGBT region by the top surface of the substrate being recessed, and a second portion provided on one side of the first portion and thicker than the first portion.

A semiconductor device includes a backside contact and a substrate. An epitaxial field stop region may be formed on the substrate with a graded doping profile that decreases with distance away from the substrate, and an epitaxial drift region may be formed adjacent to the epitaxial field stop region. A frontside device may be formed on the epitaxial drift region.

A power semiconductor device includes an active cell region with a drift region of a first conductivity type, a plurality of IGBT cells arranged within the active cell region, each of the IGBT cells includes at least one trench that extends into the drift, an edge termination region surrounding the active cell region, a transition region arranged between the active cell region and the edge termination region, at least some of the IGBT cells are arranged within or extend into the transition region, a barrier region of a second conductivity type, the barrier region is arranged within the active cell region and in contact with at least some of the trenches of the IGBT cells and does not extend into the transition region, and a first load terminal and a second load terminal, the power semiconductor device is configured to conduct a load current along a vertical direction between.

Disclosed is a transistor device which includes a semiconductor body having a first surface, a source region, a drift region, a body region being arranged between the source region and the drift region, a gate electrode adjacent the body region and dielectrically insulated from the body region by a gate dielectric, and a field electrode adjacent the drift region and dielectrically insulated from the drift region by a field electrode dielectric, wherein the field electrode comprises a first layer and a second layer, wherein the first layer has a lower electrical resistance than the second layer, wherein a portion of the second layer is disposed above and directly contacts a portion of the first layer.

In a semiconductor device, a semiconductor substrate has an IGBT region and a FWD, and includes a first conductivity type drift layer, a second conductivity type base layer disposed on the drift layer, a second conductivity type collector layer disposed opposite to the base layer with respect to the drift layer in the IGBT region, and a first conductivity type cathode layer disposed opposite to the base layer with respect to the drift layer in the FWD region. The collector layer includes an extension portion that covers only a part of the cathode layer on a side adjacent to the drift layer. Alternatively, the collector layer includes an extension portion that entirely covers a region of the cathode layer adjacent to the drift layer, and has an area density of 3.5×10.sup.12 cm.sup.−2 or less.

Provided is a semiconductor device including: a buffer region having a doping concentration higher than a bulk donor concentration; a first low-concentration hydrogen peak in the buffer region; a second low-concentration hydrogen peak in the buffer region closer to a lower surface than the first low-concentration hydrogen peak; a high-concentration hydrogen peak in the buffer region closer to the lower surface than the second low-concentration hydrogen peak, the high-concentration hydrogen peak having a hydrogen chemical concentration higher than that of the second low-concentration hydrogen peak; and a flat region including a region between the two low-concentration hydrogen peaks and a region including the second low-concentration hydrogen peak, and having a doping concentration higher than a bulk donor concentration, an average value of the doping concentration being equal to or smaller than a local minimum value of a doping concentration between the second low-concentration hydrogen peak and the high-concentration hydrogen peak.

Provided is a semiconductor device including: a semiconductor substrate having a drift region of a first conductivity type; and a buffer region of the first conductivity type provided between the drift region and a lower surface of the semiconductor substrate and having a higher doping concentration than the drift region. The buffer region has two or more helium chemical concentration peaks arranged at different positions in a depth direction of the semiconductor substrate.

A semiconductor device includes an N+ type substrate, an N− type layer disposed on a first surface of the N+ type substrate and having a trench opened to a surface opposite to the surface facing the N+ type substrate, a P type region disposed in the N− type layer and disposed on a side surface of the trench, a gate electrode disposed in the trench, and a source electrode and a drain electrode insulated from the gate electrode. The N− type layer includes a P type shield region covering a bottom surface and an edge of the trench.

A semiconductor device includes: a semiconductor substrate including a front surface, a back surface that is opposite to the front surface, and a drift layer of a first conductive type disposed between the front surface and the back surface; a first diffusion layer of a second conductive type provided between the drift layer and the front surface; a second diffusion layer provided between the drift layer and the back surface; a first buffer layer of the first conductive type provided between the drift layer and the second diffusion layer, having a concentration higher than that of the drift layer, and into which a proton is injected; and a second buffer layer of the first conductive type provided between the first buffer layer and the second diffusion layer and having a concentration higher than that of the drift layer, wherein a peak concentration of the second buffer layer is higher than a peak concentration of the first buffer layer, an impurity concentration of the first buffer layer gradually decreases toward the back surface, a length from a peak position of the first buffer layer to a boundary between the drift layer and the first buffer layer is represented by Xa, a length from the peak position to a boundary between the first buffer layer and the second buffer layer is represented by Xb, and Xb>5 Xa.