A vertical JFET made by a process using a limited number of masks. A first mask is used to form mesas and trenches in active cell and termination regions simultaneously. A maskless self-aligned process is used to form silicide source and gate contacts. A second mask is used to open windows to the contacts. A third mask is used to pattern overlay metallization. An optional fourth mask is used to pattern passivation. Optionally the channel may be doped via angled implantation, and the width of the trenches and mesas in the active cell region may be varied from those in the termination region.

A vertical JFET made by a process using a limited number of masks. A first mask is used to form mesas and trenches in active cell and termination regions simultaneously. A mask-less self-aligned process is used to form silicide source and gate contacts. A second mask is used to open windows to the contacts. A third mask is used to pattern overlay metallization. An optional fourth mask is used to pattern passivation. Optionally the channel may be doped via angled implantation, and the width of the trenches and mesas in the active cell region may be varied from those in the termination region.

An electronic power device includes a substrate of silicon carbide (SiC) having a front surface and a rear surface which lie in a horizontal plane and are opposite to one another along a vertical axis. The substrate includes an active area, provided in which are a number of doped regions, and an edge area, which is not active, distinct from and surrounding the active area. A dielectric region is arranged above the front surface, in at least the edge area. A passivation layer is arranged above the front surface of the substrate, and is in contact with the dielectric region in the edge area. The passivation layer includes at least one anchorage region that extends through the thickness of the dielectric region at the edge area, such as to define a mechanical anchorage for the passivation layer.

The fabrication method for a silicon carbide semiconductor device according to this disclosure includes a step of forming a dielectric film over part of a silicon carbide layer, a step of forming an ohmic electrode adjoining the dielectric film on the silicon carbide layer, a step of removing an oxidized layer on the ohmic electrode, a step of forming a mask with its opening on the side opposite to the side where the ohmic electrode is adjoining the dielectric film on the ohmic electrode having the oxidized layer removed and on the dielectric film, and a step of wet etching of a film to be etched with hydrofluoric acid with the mask formed. With the fabrication method for a silicon carbide semiconductor device described in this disclosure, it is possible to fabricate a silicon carbide semiconductor device with reduced failure.

A semiconductor device according to an embodiment includes a silicon carbide layer, an insulating layer, and a region provided between the silicon carbide layer and the insulating layer, the region including a plurality of first atoms of one element from the group consisting of nitrogen (N), phosphorus (P), arsenic (As), antimony (Sb), and bismuth (Si), at least some of the plurality of first atoms being four-fold coordinated atoms and/or five-fold coordinated atoms.

A semiconductor device includes: a first conductivity type semiconductor substrate made of silicon carbide; a second conductivity type body region in a device region of the semiconductor substrate; a first conductivity type source region formed in the body region; and a gate electrode formed on the body region through gate insulating films. The semiconductor device further includes, in a termination region of the semiconductor substrate, second conductivity type RESURF layers, and an edge termination region formed in the RESURF layers. Then, the RESURF layers and a front surface of the semiconductor substrate adjacent to the RESURF layers are covered by an oxidation-resistant insulating film.

In a semiconductor device, an interlayer insulating film electrically insulating a gate electrode and a source electrode has a structure in which a BPSG film and a NSG film are sequentially stacked. Further, the interlayer insulating film has a structure in which the BPSG film, the NSG film, and a SiN film are sequentially stacked, or a structure in which the BPSG film, the SiN film, and the NSG film are sequentially stacked. Such a structure enables the reliability of the semiconductor device in which a pin-shaped electrode is bonded by solder to be improved.

A Schottky diode is disclosed that includes a silicon carbide substrate, a silicon carbide drift layer, a Schottky contact, and a passivation structure. The silicon carbide drift layer provides an active region and an edge termination region about the active region. The Schottky contact has sides and a top extending between the two sides and includes a Schottky layer over the active region and an anode contact over the Schottky layer. The passivation structure covers the edge termination region, the sides of the Schottky contact, and at least a portion of the top of the Schottky contact. The passivation structure includes a first silicon nitride layer, a silicon dioxide layer over the first silicon nitride layer, and a second silicon nitride layer over the silicon dioxide layer.

A trench has first to third side surfaces respectively constituted of first to third semiconductor layers. A first side wall portion included in a first insulating film has first to third regions respectively located on the first to third side surfaces. A second insulating film has a second side wall portion located on the first side wall portion. The second side wall portion has one end and the other end, the one end being connected to the second bottom portion of the second insulating film, the other end being located on one of the first and second regions, the other end being separated from the third region.

A SIC transistor device includes a silicon-carbide semiconductor substrate having a plurality of first doped regions laterally spaced apart from one another and beneath a main surface of the substrate, a second doped region extending from the main surface to a third doped region that is above the first doped regions, and a plurality of fourth doped regions in the substrate extending from the main surface to the first doped regions. The second doped region has a first conductivity type. The first, third and fourth doped regions have a second conductivity type opposite the first conductivity type. A gate trench extends through the second and third doped regions. The gate trench has sidewalls, a bottom and rounded corners between the bottom and the sidewalls.