Provided is a semiconductor device including: a buffer region having one or more doping concentration peaks having a higher doping concentration than a drift region; and a lifetime control portion provided at a position overlapping a shallowest concentration peak closest to a lower surface of a semiconductor substrate among the doping concentration peaks provided in the buffer region, and in which a carrier lifetime shows a local minimum value, in which the semiconductor substrate has a critical depth position at which an integrated value, which is obtained by integrating doping concentrations from an upper end of the drift region toward the lower surface, reaches a critical integrated concentration of the semiconductor substrate, and a depth position at which the carrier lifetime shows the local minimum value in the lifetime control portion is arranged closer to the lower surface than the critical depth position.

A semiconductor device is provided, which includes: a semiconductor substrate; an emitter electrode including at least two partial electrodes arranged with an interval in a top plan view of the semiconductor substrate; and an active-side gate runner and an active-side dummy runner arranged to be sandwiched between two of the partial electrodes, wherein the semiconductor substrate includes: a gate trench portion connected to the active-side gate runner and having a longitudinal length in a first direction in the top plan view, and a dummy trench portion connected to the active-side dummy runner and having a longitudinal length in the first direction, wherein the entirety of one of the active-side gate runner and the active-side dummy runner in the first direction is covered by the other of the gate runner and the dummy runner.

A semiconductor device of the embodiment includes a semiconductor layer including a first semiconductor region, a second semiconductor region, a third semiconductor region, a fourth semiconductor region, a fifth semiconductor region, a sixth semiconductor region, a first trench, and a second trench, a first gate electrode in the first trench; a second gate electrode in the second trench; a first electrode on a first face side; a second electrode on a second face side; a first electrode pad connected to the first gate electrode; and a second electrode pad connected to the second gate electrode. The semiconductor device includes a first region including the first semiconductor region; a second region including the second semiconductor region; and a third region provided between the first region and the second region, the third region having a density of the second trench higher than that of the first region.

A diode and a transistor are connected in parallel. The transistor is located on a first doped region forming a PN junction of the diode with a second doped region located under the first region. The circuit functions as an ionizing radiation detection cell by generating a current through the PN junction which changes by a voltage generated across the transistor. This change in voltage is compared to a threshold to detect the ionizing radiation.

A semiconductor device includes a semiconductor substrate, a transistor section, a diode section, and a boundary section provided between the transistor section and the diode section in the semiconductor substrate. The transistor section has gate trench portions which are provided from an upper surface of the semiconductor substrate to a position deeper than that of an emitter region, and to each of which a gate potential is applied. An upper-surface-side lifetime reduction region is provided on the upper surface side of the semiconductor substrate in the diode section and a partial region of the boundary section, and is not provided in a region that is overlapped with the gate trench portion in the transistor section in a surface parallel to the upper surface of the semiconductor substrate.

A diode and a transistor are connected in parallel. The transistor is located on a first doped region forming a PN junction of the diode with a second doped region located under the first region. The circuit functions as an ionizing radiation detection cell by generating a current through the PN junction which changes by a voltage generated across the transistor. This change in voltage is compared to a threshold to detect the ionizing radiation.

A semiconductor device includes a semiconductor substrate, a transistor section, a diode section, and a boundary section provided between the transistor section and the diode section in the semiconductor substrate. The transistor section has gate trench portions which are provided from an upper surface of the semiconductor substrate to a position deeper than that of an emitter region, and to each of which a gate potential is applied. An upper-surface-side lifetime reduction region is provided on the upper surface side of the semiconductor substrate in the diode section and a partial region of the boundary section, and is not provided in a region that is overlapped with the gate trench portion in the transistor section in a surface parallel to the upper surface of the semiconductor substrate.

A semiconductor device is provided, which includes: a semiconductor substrate; an emitter electrode including at least two partial electrodes arranged with an interval in a top plan view of the semiconductor substrate; and an active-side gate runner and an active-side dummy runner arranged to be sandwiched between two of the partial electrodes, wherein the semiconductor substrate includes: a gate trench portion connected to the active-side gate runner and having a longitudinal length in a first direction in the top plan view, and a dummy trench portion connected to the active-side dummy runner and having a longitudinal length in the first direction, wherein the entirety of one of the active-side gate runner and the active-side dummy runner in the first direction is covered by the other of the gate runner and the dummy runner.

Directly beneath p.sup.−-type base regions, n-type storage regions are provided. The storage regions contain hydrogen donors as an impurity and have an impurity concentration higher than that of the n.sup.−-type drift region. The storage regions are formed by hydrogen ion irradiation from a back surface of a semiconductor substrate. The storage regions have a peak hydrogen concentration and are at positions that coincide with where the hydrogen ions have been irradiated. By the hydrogen ion irradiation, a crystal defect region that is a carrier lifetime killer region is formed concurrently with the storage regions, closer to the back surface of the semiconductor substrate than are storage regions. The crystal defect region has a crystal defect density with a peak density at a position closer to the back surface of the semiconductor substrate than are the storage regions. A semiconductor device having such storage regions and a carrier lifetime killer region is enabled.

A semiconductor device includes a semiconductor substrate, an emitter region, a base region and multiple accumulation areas, and an upper accumulation area in the multiple accumulation areas is in direct contact with a gate trench section and a dummy trench section, in an arrangement direction that is orthogonal to a depth direction and an extending direction, a lower accumulation area furthest from the upper surface of the semiconductor substrate in the multiple accumulation areas has: a gate vicinity area closer to the gate trench section than the dummy trench section in the arrangement direction; and a dummy vicinity area closer to the dummy trench section than the gate trench section in the arrangement direction, and having a doping concentration of the first conductivity type lower than that of the gate vicinity area.