Fuji Electric Co., Ltd.

Fuji Electric Systems Co. Ltd.

Fuji Electric Holdings Co., Ltd.

Setsuko Wakimoto

Masanobu Iwaya

Naoto Fujishima

Manabu Takei

Mutsumi Kitamura

Akio Sugi

Katsuya Tabuchi

Shinji Fujikake

Koh Yoshikawa

Keiji Okumura

Hitoshi Kuribayashi

The method for adjusting a groove depth includes: preparing masks having different thicknesses on respective top surfaces of a plurality of substrates made of silicon carbide; forming a first opening having a predetermined width and a second opening having a width wider than the first opening in each of the masks; simultaneously forming a first groove and a second groove in each of the substrates by selectively etching via the first opening and the second opening; measuring a depth ratio of the first groove to the second groove in each of the substrates; and acquiring a thickness of a mask such that the depth ratio is an intended value, from a relationship between each thickness of the masks and each depth ratio in the substrate.

Method for adjusting groove depth and method for manufacturing semiconductor device

A silicon carbide semiconductor device, including a semiconductor substrate having first and second semiconductor regions and a plurality of third semiconductor regions sequentially formed therein, a plurality of trenches penetrating the second and third semiconductor regions, a plurality of gate electrodes provided in the trenches via a gate insulating film, an interlayer insulating film covering the gate electrodes, a plurality of contact holes penetrating the interlayer insulating film, a first electrode provided in the contact holes and at the surface of the interlayer insulating film, and a second electrode electrically connected to the first semiconductor region. The interlayer insulating film has a plurality of recessed parts and protruding parts, to thereby form at least three recesses and protrusions repeatedly at a surface of the interlayer insulating film. The first electrode includes first to third electrode films, the second electrode film having a shape reflecting the surface of the interlayer insulating film.

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

In a vertical MOSFET of a trench gate structure, a high-concentration implantation region is provided in a p-type base region formed from a p-type silicon carbide layer formed by epitaxial growth, so as to include a portion in which a channel is formed. The high-concentration implantation region is formed by ion implantation of a p-type impurity into the p-type silicon carbide layer. The high-concentration implantation region is formed by p-type ion implantation and has an impurity concentration profile in which concentration differences in a depth direction form a bell-shaped curve at a peak of impurity concentration that is higher than that of the p-type silicon carbide layer. In the p-type base region, disorder occurs partially in the crystal structure consequent to the ion implantation for forming the high-concentration implantation region.

Method of manufacturing silicon carbide semiconductor device

The present invention provides a process for producing a semiconductor device having a breakdown voltage heightened by improving the step coverage properties of the interlayer dielectric for covering polysilicon electrodes. The process includes a step in which a gate insulating film is formed on a silicon carbide substrate, a step in which a polysilicon film is formed on the gate insulating film, a step in which one or more dopants of N, P, As, Sb, B, Al, and Ar are ion implanted into the polysilicon film, and a step in which a mask is selectively formed on the polysilicon film. The exposed portions of the polysilicon film are removed by isotropic dry etching. Thus, polysilicon electrodes can be formed so that in each polysilicon electrode, the hem part sandwiched between the bottom surface and the lateral surface of the polysilicon electrode has an inclination angle of 60&#xb0; or less.

Process for making silicon carbide semiconductor device

A silicon carbide semiconductor device, including a silicon carbide substrate, multiple trenches provided in the silicon carbide substrate, a first semiconductor region provided between each adjacent two of the trenches, a second semiconductor region selectively provided in the first semiconductor region, multiple third semiconductor regions selectively provided in the silicon carbide substrate to each cover a bottom of one trench, multiple fourth semiconductor regions selectively provided in the silicon carbide substrate, each between adjacent two of the trenches and being in contact with the first semiconductor region, multiple gate electrodes, each provided via a gate insulating film in one of the trenches, a first electrode connected to the first and second semiconductor regions, and a second electrode connected to the rear surface of the silicon carbide substrate. At least two of the trenches are arranged between each adjacent two of the fourth semiconductor regions.

Silicon carbide semiconductor device having stacked epitaxial layers

A semiconductor device is disclosed which improves the breakdown voltage of a planar-type junction edge terminating structure. The device includes an n-type semiconductor substrate layer common to an active section and an edge terminating section. An n-type drift region is formed selectively on the n-type semiconductor substrate layer in the active section and a p-type partition region is formed selectively on the n-type semiconductor substrate layer in the active section. A p-type base/body region is formed on the n-type drift region and the partition region. A source electrode is connected electrically to the p-type base/body region. A p-type partition region is formed in the edge terminating section between the p-type base/body region and the scribe plane of the semiconductor device such that the p-type partition region in the edge terminating section surrounds the p-type base/body region. A drain electrode is connected electrically to the n-type semiconductor substrate layer.

Semiconductor device having improved breakdown voltage and method of manufacturing the same

A semiconductor device has a MOS gate side surface structure, including a gate electrode filling a trench formed in a semiconductor substrate with an insulator film between the trench and the gate electrode, a gate insulator film covering the surface of the gate electrode, a buffer region of one conductivity type in contact with the semiconductor substrate, a base region of the other conductivity type adjacent to the buffer region on the gate insulator film, and an emitter region of the one conductivity type adjacent to the base region on the side opposite to the buffer region. The semiconductor device and the method of manufacturing thereof can further improve the tradeoff between the on-voltage and the turn-off loss by increasing the amount of electrons injected from a cathode on the surface to increase an amount of carriers on the cathode side in a stable turned-on state of the device.

Semiconductor device and manufacturing method thereof

Gate electrodes of a TLPM and gate electrodes of planar devices are formed by patterning a same polysilicon layer. Drain electrode(s) and source electrode(s) of the TLPM and drain electrodes and source electrodes of the planar devices are formed by patterning a same metal layer. Therefore, the TLPM and the planar devices can be connected electrically to each other by resulting metal wiring layers and polysilicon layers without the need for performing wire bonding on a printed circuit board.

Growing community of inventors

Matsumoto, Japan

Setsuko Wakimoto