An IGBT manufacturing method is provided. The IGBT has an n-type emitter region, a p-type top body region, an n-type intermediate region, a p-type bottom body region, an n-type drift region, a p-type collector region, trenches penetrating the emitter region, the top body region, the intermediate region and the bottom body region from an upper surface of a semiconductor substrate and reaching the drift region, and gate electrodes formed in the trenches. The method includes forming the trenches on the upper surface of the semiconductor substrate, forming the insulating film in the trenches, forming an electrode layer on the semiconductor substrate and in the trenches after forming the insulating film, planarizing an upper surface of the electrode layer, and implanting n-type impurities to a depth of the intermediate region from the upper surface side of the semiconductor substrate after planarizing the upper surface of the electrode layer.

An insulated gate bipolar transistor device includes a semiconductor substrate having a drift region of an insulated gate bipolar transistor structure, a first fin structure starting from the drift region of the semiconductor substrate and extending orthogonal to a main surface of the semiconductor substrate, and a first gate structure of the insulated gate bipolar transistor structure extending alma at least a part of the first fin structure.

An IGBT has an emitter region, a top body region that is formed below the emitter region, a floating region that is formed below the top body region, a bottom body region that is formed below the floating region, a trench, a gate insulating film that covers an inner face of the trench, and a gate electrode that is arranged inside the trench. When a distribution of a concentration of p-type impurities in the top body region and the floating region, which are located below the emitter region, is viewed along a thickness direction of a semiconductor substrate, the concentration of the p-type impurities decreases as a downward distance increases from an upper end of the top body region that is located below the emitter region, and assumes a local minimum value at a predetermined depth in the floating region.

A semiconductor device according to an embodiment includes a first semiconductor layer of a first conductivity type, a second semiconductor layer of a second conductivity type, a third semiconductor layer of the first conductivity type, a fourth semiconductor layer of the second conductivity type, a first electrode connected to the second semiconductor layer and the fourth semiconductor layer, a second electrode facing the second semiconductor layer with an insulating film interposed, a fifth semiconductor layer of the second conductivity type, a sixth semiconductor layer of the first conductivity type, a seventh semiconductor layer of the second conductivity type, a third electrode connected to the fifth semiconductor layer and the seventh semiconductor layer, and a fourth electrode facing the fifth semiconductor layer with an insulating film interposed.

A semiconductor device includes a SiC layer having a first surface, a gate insulating film on the first surface, a gate electrode on the gate insulating film, a first SiC region of a first conductivity type in the SiC layer, a second SiC region of a second conductivity type in the first SiC region, a third SiC region of the first conductivity type in the second SiC region, wherein a boundary between the second SiC region and the third SiC region, and the first surface forms a first angle, and a fourth SiC region of the first conductivity type in the third SiC region, having an impurity concentration of the first conductivity type higher than that of the third SiC region, wherein a boundary between the third SiC region and the fourth SiC region, and the first surface forms a second angle that is smaller than the first angle.

Provided is a semiconductor device according to an embodiment including: a first electrode; a second electrode; a third electrode provided between the first electrode and the second electrode; a first insulating film provided between the third electrode and the second electrode; a silicon carbide layer provided between the first insulating film and the second electrode; a first silicon carbide region provided between the third electrode and the second electrode, the first silicon carbide region being provided in the silicon carbide layer; a second silicon carbide region provided between the third electrode and the first silicon carbide region, the second silicon carbide region being provided in the silicon carbide layer; a third silicon carbide region provided between the third electrode and the second silicon carbide region, the third. silicon carbide region being provided in the silicon carbide layer; a fourth silicon carbide region provided between the third silicon carbide region and the second silicon carbide region, the fourth silicon carbide region being provided in the silicon carbide layer; and a fourth electrode provided between the first electrode and the fourth silicon carbide region, the fourth electrode being provided laterally adjacent to the third silicon carbide region, the fourth electrode containing a metal silicide, a first distance between the first electrode and a first interface between the fourth electrode and the fourth silicon carbide region being longer than a second distance between the first electrode and a second interface between the third silicon carbide region and the fourth silicon carbide region, and a third distance between a third interface between the fourth electrode and the first electrode and a fourth interface between the third silicon carbide region and the fourth silicon carbide region being shorter than a fourth distance between the fourth interface and a fifth interface between the third silicon carbide region and the first electrode.

The present invention provides a switching device (100) for power conversion in which a first gate electrode (6), a p-type channel layer (2) having an n-type emitter region (3), a second gate electrode (13), and a p-type floating layer (15) are repeatedly arranged in order on the surface side of an n-type semiconductor substrate (1). An interval a between the two gates (6, 13) that sandwich the p-type channel layer (2) is configured to be smaller than an interval b between the two gates (13, 6) that sandwich the p-type floating layer (15). The first gate electrode (6) and the second gate electrode (13) are both supplied with drive signals having a time difference in drive timing.

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.

A method for manufacturing an insulated gate bipolar transistor (100) comprises: providing a substrate (10), forming a field oxide layer (20) on a front surface of the substrate (10), and forming a terminal protection ring (23); performing photoetching and etching on the active region field oxide layer (20) by using an active region photomask, introducing N-type ions into the substrate (10) by using a photoresist as a mask film; depositing and forming a polysilicon gate (31) on the etched substrate (10) of the field oxide layer (20), and forming a protection layer on the polysilicon gate (31); performing junction pushing on an introduction region of the N-type ions, and then forming a carrier enhancement region (41); performing photoetching by using a P well photomask, introducing P-type ions into the carrier enhancement region (41), and performing junction pushing and then forming a P-body region; performing, by means of the polysilicon gate, self-alignment introduction of N-type ions into the P-body region, and performing junction pushing and then forming an N-type heavily doped region; forming sidewalls on two sides of the polysilicon gate, introducing P-type ions into the N-type heavily doped region, and performing junction pushing and then forming a P-type heavily doped region; and removing the protection layer, and then performing introduction and doping of the polysilicon gate. The method reduces a forward voltage drop disposing the carrier enhancement region.

A manufacturing method of a power MOSFET employs a hard mask film over a portion of the wafer surface as a polishing stopper, between two successive polishing steps. After embedded epitaxial growth is performed in a state where a hard mask film for forming trenches is present in at least a scribe region of a wafer, primary polishing is performed by using the hard mask film as a stopper, and secondary polishing is then performed after the hard mask film is removed.