A semiconductor device comprising a semiconductor substrate including an upper surface and a lower surface wherein a donor concentration of a drift region is higher than a base doping concentration of the semiconductor substrate, entirely over the drift region in a depth direction connecting the upper surface and the lower surface is provided.

A semiconductor device includes at least one IGBT cell region, at least one switchable free-wheeling diode region, and at least one non-switchable free-wheeling diode region integrated in the same semiconductor substrate as the at least one IGBT cell region and the at least one switchable free-wheeling diode region.

In order to reduce electric field concentration in a semiconductor device including a main transistor section and a sense transistor section, the semiconductor device is provided, the semiconductor device including a semiconductor substrate of a first conductivity type, a main transistor section in an active region on the semiconductor substrate, and a sense transistor section outside the active region on the semiconductor substrate, wherein the active region is provided with a main well region of a second conductivity type, and wherein the sense transistor section has a sense gate trench section formed extending from the outside of the active region to the main well region on the front surface of the semiconductor substrate.

A semiconductor device, in which, in a density distribution of first conductivity type impurities in the first conductivity type region measured along a thickness direction of the semiconductor substrate, a local maximum value N1, a local minimum value N2, a local maximum value N3, and a density N4 are formed in this order from front surface side, a relationship of N1>N3>N2>N4 is satisfied, a relationship of N3/10>N2 is satisfied, and a distance a from the surface to the depth having the local maximum value N1 is larger than twice a distance b from the depth having the local maximum value N1 to the depth having the local minimum N2.

A semiconductor device includes a semiconductor substrate; and a temperature sense diode fixed on the semiconductor substrate. The temperature sense diode includes: an anode electrode; a p-type semiconductor layer being in contact with the anode electrode; an n-type semiconductor layer being in contact with the p-type semiconductor layer; and a cathode electrode being in contact with the n-type semiconductor layer; and the anode electrode. The p-type semiconductor layer, the n-type semiconductor layer, and the cathode electrode are stacked along a thickness direction of the semiconductor substrate. An electric resistivity of the anode electrode or the cathode electrode whichever is located closer to the semiconductor substrate is lower than an electric resistivity of the n-type semiconductor layer and an electric resistivity of the p-type semiconductor layer.

Switching loss is reduced. A first surface of a semiconductor substrate has a portion included in an IGBT region and a portion included in a diode region. Trenches formed in the first surface include a gate trench and a boundary trench disposed between the gate trench and the diode region. A fourth layer of the semiconductor substrate is provided on the first surface and has a portion included in the diode region. The fourth layer includes a trench-covering well region that covers the deepest part of the boundary trench, a plurality of isolated well regions, and a diffusion region that connects the trench-covering well region and the isolated well regions. The diffusion region has a lower impurity concentration than that of the isolated well regions. A first electrode is in contact with the isolated well regions and away from the diffusion region.

The present invention concerns a monolithically merged trenched-and-implanted Bipolar Junction Transistor (TI-BJT) with antiparallel diode and a method of manufacturing the same. Trenches are made in a collector, base, emitter stack downto the collector. The base electrode is formed on an implanted base contact region at the bottom surface of the trench. The present invention also provides for products produced by the methods of the present invention and for apparatuses used to perform the methods of the present invention.

An obtained margin is smaller than a margin to be kept for a fault period predicted by life prediction based on a power cycle test, extending a maintenance cycle for replacement and so on. A method of detecting a fault of a semiconductor device including a power device mounted on a metal base and a drive circuit for driving the power device, the method detecting a fault of the semiconductor device beforehand based on an increase in thermal resistance between the metal base and the power device. A state of the power device is measured immediately before and after the power device is driven by the drive circuit. A temperature difference of the power device before and after driving is calculated according to the result of measurement. An increase in thermal resistance between the metal base and the power device is detected based on the temperature difference and an amount of electricity inputted to the power device in the driving period, and a fault of the semiconductor device is detected beforehand according to the increase.

An IGBT is disposed in an IGBT portion, and an FWD is disposed in an FWD portion. A p-type base region and an n.sup.-type drift region are alternately exposed in a trench longitudinal direction in a substrate front surface in a mesa portion between neighboring trenches in the IGBT portion. A p-type anode region and the n.sup.-type drift region are alternately exposed in the trench longitudinal direction in the substrate front surface in a mesa portion in the FWD portion, and a repetitive structure is formed with a portion of the n.sup.-type drift region sandwiched between p-type anode regions and one p-type anode region in contact with the portion as one unit region. The proportion occupied by the p-type anode region in one unit region (an anode ratio) () is 50% to 100%.

A semiconductor device is provided, including: a semiconductor substrate; an active portion provided on the semiconductor substrate; a first well region and a second well region provided on the semiconductor substrate and arranged sandwiching the active portion in a top view; a peripheral well region provided on the semiconductor substrate and arranged enclosing the active portion in a top view; an intermediate well region provided on the semiconductor substrate and arranged between the first well region and the second well region in a top view; a first pad arranged above the first well region and a second pad arranged above the second well region; and a temperature sense diode arranged above the intermediate well region.