A semiconductor device having a low on-voltage of IGBT and a small reverse recovery current of the diode is provided. The semiconductor device includes a semiconductor substrate having a gate trench and a dummy trench. The semiconductor substrate includes emitter, body, barrier and pillar regions between the gate trench and the dummy trench. The emitter region is an n-type region being in contact with the gate insulating film and exposed on a front surface. The body region is a p-type region being in contact with the gate insulating film at a rear surface side of the emitter region. The barrier region is an n-type region being in contact with the gate insulating film at a rear surface side of the body region and in contact with the dummy insulating film. The pillar region is an n-type region connected to the front surface electrode and the barrier region.

A semiconductor device includes trench gate structures in a semiconductor body with hexagonal crystal lattice. A mean surface plane of a first surface is tilted to a <1-100> crystal direction by an off-axis angle, wherein an absolute value of the off-axis angle is in a range from 2 degree to 12 degree. The trench gate structures extend oriented along the <1-100> crystal direction. Portions of the semiconductor body between neighboring trench gate structures form transistor mesas. Sidewalls of the transistor mesas deviate from a normal to the mean surface plane by not more than 5 degree.

Provided is a semiconductor device having an RC-IGBT structure, the semiconductor device comprising an FWD (Free Wheel Diode) region and an IGBT (Insulated Gate Bipolar Transistor) region. Provided is a semiconductor device comprising:

a semiconductor substrate; a transistor section formed on the semiconductor substrate; a diode section formed on the semiconductor substrate and including a lifetime killer at a front surface side of the semiconductor substrate;
a gate runner provided between the transistor section and the diode section and electrically connected to a gate of the transistor section.

A semiconductor device includes a middle field stop layer having a first conductivity type impurity concentration higher than a drift layer and arranged at a position in the drift layer. A ratio of a depth of the position of the middle field stop layer from a front surface of a semiconductor substrate to a thickness of the semiconductor substrate is equal to or greater than fifteen percent and equal to or less than thirty-five percent. When an IGBT is arranged in the semiconductor device, vibration of a collector voltage waveform in a switching off of the IGBT is restricted. When a diode is arranged in the semiconductor device, vibration of a recovery waveform in a recovery operation of the diode is restricted. Accordingly, at least one of the vibrations of the recovery waveform and the collector voltage waveform in the switching is restricted.

Provided is a semiconductor device having transistor and diode sections. The semiconductor device comprises: a gate metal layer provided above the upper surface of a semiconductor substrate; an emitter electrode provided above the upper surface of the semiconductor substrate; a first conductivity-type emitter region provided on the semiconductor substrate upper surface side in the transistor section; a gate trench section, which is provided on the semiconductor substrate upper surface side in the transistor section, is electrically connected to the gate metal layer, and is in contact with the emitter region; an emitter trench section, which is provided on the semiconductor substrate upper surface side in the diode section, and is electrically connected to the emitter electrode; and a dummy trench section, which is provided on the semiconductor substrate upper surface side, is electrically connected to the gate metal layer, and is not in contact with the emitter region.

Provided is a semiconductor device including a semiconductor substrate doped with impurities, a front surface-side electrode provided on a front surface side of the semiconductor substrate, a back surface-side electrode provided on a back surface side of the semiconductor substrate, wherein the semiconductor substrate has a peak region arranged on the back surface side of the semiconductor substrate and having one or more peaks of impurity concentration, a high concentration region arranged closer to the front surface than the peak region and having a gentler impurity concentration than the one or more peaks, and a low concentration region arranged closer to the front surface than the high concentration region and having a lower impurity concentration than the high concentration region.

At least one bipolar transistor and at least one variable capacitance diode are jointly produced by a method on a common substrate.

In a back surface hole injection type diode, by more effectively securing the effect of hole injection from the back surface of a semiconductor substrate, the performance of a semiconductor device is improved. In the semiconductor device, in a diode formed of a P-N junction including an anode P-type layer formed in the main surface of a semiconductor substrate and a back surface N.sup.+-type layer formed in the back surface of the semiconductor substrate, a back surface P.sup.+-type layer is formed in the back surface, and a surface P.sup.+-type layer is formed in the main surface right above the back surface P.sup.+-type layer to thereby promote the effect of hole injection from the back surface.

The re-combination center introduction region has re-combination centers introduced therein so that a density of the re-combination centers in the re-combination center introduction region is higher than a density of re-combination centers in a periphery of the re-combination center introduction region. The re-combination center introduction region continuously extends from the diode region to the peripheral region along a longitudinal direction of the diode region.

Provided is a semiconductor device comprising a semiconductor substrate that includes a transistor region; an emitter electrode that is provided on the semiconductor substrate; a first dummy trench portion that is provided on the transistor region of the semiconductor substrate and includes a dummy conducting portion that is electrically connected to the emitter electrode; and a first contact portion that is a partial region of the transistor region, provided between an end portion of a long portion of the first dummy trench portion and an end portion of the semiconductor substrate, and electrically connects the emitter electrode and a semiconductor region with a first conductivity type provided in the transistor region.