Fuji Electric Co., Ltd.

Yuichi Hashizume

Yasuyuki Hoshi

Keishirou Kumada

Yoshihisa Suzuki

Naoyuki Ohse

Kunio Hibino

Takahito Kojima

Takafumi Uchida

A silicon carbide semiconductor device is a SiC-SBD that has, in an active region, at a front surface of a semiconductor substrate containing silicon carbide, a mixture of a SBD structure having Schottky barrier junctions between a titanium film that is a lowermost layer of a front electrode and an n-type drift region, and a JBS structure having pn junction portions between p-type regions and the n-type drift region. The p-type regions form ohmic junctions with the titanium film that is the lowermost layer of the front electrode. After an ion implantation for the p-type regions, activation annealing is performed at a temperature in a range of 1700 degrees C. to 1900 degrees C. for a treatment time exceeding 20 minutes, whereby contact resistance between the titanium film and the p-type regions is adjusted to be in a range of about 5×10Ω·cmto 8×10Ω·cm.

Silicon carbide Schottky barrier diode

A source pad of a main semiconductor element is electrically connected to an n-type source region via a barrier metal. A temperature sensing part is a poly-silicon diode formed by a pn junction between a p-type poly-silicon layer that is a p-type anode region and an n-type poly-silicon layer that is an n-type cathode region. The temperature sensing part is provided, via the field insulating film, on a front surface of a same semiconductor substrate as the main semiconductor element. An anode pad and a cathode pad are in direct contact with the p-type poly-silicon layer and the n-type poly-silicon layer, respectively. The source pad, the anode pad, and the cathode pad are aluminum alloy films.

Semiconductor device

A semiconductor device having, in a plan view, a termination region surrounding an active region. The semiconductor device includes a semiconductor substrate containing silicon carbide, a first-conductivity-type region provided in the semiconductor substrate at its first main surface, a plurality of first second-conductivity-type regions selectively formed in the semiconductor substrate at its first main surface, a plurality of silicide films respectively in ohmic contact with the first second-conductivity-type regions, a first electrode that is in contact with the silicide films to form ohmic regions, with the first second-conductivity-type regions to form non-operating regions, and with the first-conductivity-type region to form Schottky regions, a second electrode provided at a second main surface of the semiconductor substrate, and a second second-conductivity-type region provided in the termination region. The ohmic regions, the non-operating regions and the Schottky regions are formed in the active region in a striped pattern. The second second-conductivity-type region connects the ohmic regions and the non-operating regions.

Silicon carbide semiconductor device and method of manufacturing silicon carbide semiconductor device

A silicon carbide semiconductor device includes a first semiconductor layer of a first conductivity type provided on a front surface of a semiconductor substrate of the first conductivity type; a second semiconductor layer of a second conductivity type; a first semiconductor region of the first conductivity type; and a gate electrode having a striped-shape and provided on a gate insulating film. The silicon carbide semiconductor device further includes a first electrode provided on a surface of the second semiconductor layer and the first semiconductor region; a step film provided on the first electrode; a plating film provided on the first electrode and the step film; and a solder on the plating film. The step film is provided on the first electrode on which the solder and the plating film are provided, the step film being provided so as to be embedded in grooves formed on the first electrode.

Silicon carbide semiconductor device having a step film formed between a plating film and a first electrode

A silicon carbide semiconductor device includes a first semiconductor layer of a first conductivity type on a substrate of the first conductivity type, a second semiconductor layer of a second conductivity type on the first semiconductor layer, and a first semiconductor region of the first conductivity type. The semiconductor device further includes a gate electrode provided in a plurality of trenches via gate insulating films, a protruding portion disposed on the second semiconductor layer at a bridge area between two adjacent ones of the trenches in a direction orthogonal to the trenches, an interlayer insulating film provided on the gate electrode, and having contact holes that form a striped pattern, a first electrode on the interlayer insulating film and in the contact holes, a plating film provided in a plating area, and a solder on the plating film.

In an effective region of an active region, a main semiconductor element and a source pad thereof are disposed. A non-operating region of the active region excludes the effective region and is a high-function region in which a gate pad of the main semiconductor element and other electrode pads are disposed. An edge termination region and the electrode pads are separated by an interval equivalent to at least a width of one unit cell of the main semiconductor element. In the high-function region, at a border of the edge termination region, a lead-out electrode is provided on a front surface of a semiconductor substrate. The lead-out electrode has a function of leading out displacement current that flows to the high-function region from the edge termination region when the main semiconductor element is OFF. Thus, destruction at the edge termination region may be suppressed.

A semiconductor device includes a semiconductor substrate, a first semiconductor layer of a first conductivity type, a second semiconductor layer of a second conductivity type, a first semiconductor region of the first conductivity type, a second semiconductor region of the second conductivity type, a gate electrode, a first electrode, and a gate electrode pad. A first lower region opposing the gate electrode pad in a depth direction has a carrier recombination rate that is lower than that of a second lower region opposing the first electrode in the depth direction. With such a configuration, when high electric potential is applied to a source electrode and a built-in PN diode is driven, the generation of crystal defects may be suppressed.

Semiconductor device and method of manufacturing semiconductor device

A silicon carbide semiconductor device has a rectangle-shaped active region in which a main current flows, and a termination region surrounding the active region in a plan view. The device includes a silicon carbide semiconductor substrate of a first conductivity type, a first semiconductor layer of the first conductivity type on the front surface of the substrate, a second semiconductor layer of a second conductivity type, at a surface at the first semiconductor layer, a first semiconductor region of the first conductivity type, selectively provided in the second semiconductor layer, the second semiconductor region disposed from a periphery of the active region to reach the termination region, and extending along each of directions of four sides of the active region. At the four sides of the active region, a cross-sectional structure of each layer and each region of the device is identical to one another.

A semiconductor device includes a semiconductor substrate, a first semiconductor layer of a first conductivity type, a second semiconductor layer of a second conductivity type, a third semiconductor layer of the second conductivity type, a first semiconductor region of the first conductivity type, a second semiconductor region of the first conductivity type, a gate insulating film, and a gate electrode. A threshold voltage of the semiconductor device is higher than forward voltage of a built-in PN diode constituted by the second semiconductor layer, the semiconductor substrate, and the first semiconductor layer. Thus, when high electric potential is applied to a source electrode and the built-in PN diode is driven, the generation of crystal effects may be suppressed.

In a transistor region of an active region, trench-gate MOS gates for a vertical MOSFET are formed on the front surface side of a semiconductor substrate. In a non-effective/pad region of the active region, a gate pad is formed on the front surface of the semiconductor substrate with an interlayer insulating film interposed therebetween. An n-type region is formed spanning across the entire non-effective region in the surface layer of the front surface of the semiconductor substrate. The portion directly beneath the gate pad is only an n-type region constituted by an nstarting substrate, an ndrift region, and the n-type region, with the interlayer insulating film sandwiched thereabove. No nsource region is formed in a p-type base region extension which is the portion of a p-type base region that extends into the non-effective region.

Semiconductor device and semiconductor circuit device

A silicon carbide semiconductor device includes a semiconductor substrate of a first conductivity type; an active region in which a main current flows provided on the semiconductor substrate; a termination region disposed outside of the active region and in which a voltage withstanding structure is formed; and a damaged region disposed outside the termination region and in which crystallinity is impaired, the damaged region being exposed at a cut surface that is formed when singulation is performed.

Silicon carbide semiconductor device and method of manufacturing a silicon carbide semiconductor device

An interlayer insulating film covers a gate electrode and a gate insulating film embedded in a trench. A source electrode includes a first TiN film, a NiSi film, a Ti film, a second TiN film, and an Al alloy film. The first TiN film covers a part of the interlayer insulating film so as to not contact a semiconductor substrate at a bottom of a contact hole. The NiSi film forms an ohmic contact with the semiconductor substrate in the contact hole. The Ti film, the second TiN film, and the Al alloy film are sequentially stacked on surfaces of the first TiN film and the NiSi film, spanning a front surface of the semiconductor substrate, from on the interlayer insulating film. A terminal pin is soldered to the source electrode, in an upright position orthogonal to the front surface of the semiconductor substrate.

A semiconductor device includes a semiconductor substrate, a first semiconductor layer of a first conductivity type, a second semiconductor layer of a second conductivity type, a first semiconductor region of the first conductivity type, a second semiconductor region of the second conductivity type, a gate insulating film, and a gate electrode. The semiconductor device further includes, in a region of the first semiconductor layer across or adjacent to a p-n junction therein that does not overlap the second semiconductor region in a plan view except lateral edges thereof, a lifetime killer region having lifetime killers implanted therein.

Semiconductor device with lifetime killers and method of manufacturing the same

A method of manufacturing a magnetic recording medium includes providing a substrate that is a magnetic recording medium substrate having a disc shape, having two main surfaces, and having defined therein a center hole; holding the center hole of the substrate from both main surfaces with two holding members that each have a disc shape to hold the substrate and to cover at least the periphery of the center hole adjacent to the two main surfaces of the substrate; and applying resist liquid simultaneously to both main surfaces of the substrate using spin coating to form a resist layer simultaneously on both main surfaces while maintaining the periphery of the center hole immediately adjacent to the two main surfaces of the substrate resist-free as an unapplied portion. The method enables efficient formation of uniform resist layers without defects on both faces of the substrate.

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Matsumoto, Japan

Yuichi Hashizume