Abstract: A semiconductor device provided herein includes: a fourth region of a p-type being in contact with a lower end of the gate trench; a termination trench provided in the front surface in a range outside the second region; a lower end p-type region of the p-type being in contact with a lower end of the termination trench; a lateral p-type region of the p-type being in contact with a lateral surface of the termination trench on an outer circumferential side, connected to the lower end p-type region, and exposed on the front surface; and a plurality of guard ring regions provided on the outer circumferential side with respect to the lateral p-type region and exposed on the front surface.

Abstract: A semiconductor device includes a termination trench surrounding a region in which a plurality of gate trenches is provided; a p-type lower end region being in contact with a lower end of the termination trench; a p-type outer circumference region being in contact with the termination trench from an outer circumferential side and exposed on a surface of the semiconductor device; a plurality of guard ring regions of a p-type provided on an outer circumferential side of the p-type outer circumference region and exposed on the surface; and an n-type outer circumference region separating the p-type outer circumference region from the guard ring regions and separating the guard ring regions from each another.

Abstract: An insulating gate type semiconductor device being capable of easily depleting an outer periphery region is provided. The insulating gate type semiconductor device includes: first to fourth outer periphery trenches formed in a front surface of a semiconductor substrate; insulating layers located in the outer periphery trenches; fifth semiconductor regions being of a second conductive type and formed in ranges exposed to bottom surfaces of the outer periphery trenches; and a connection region connecting the fifth semiconductor region exposed to the bottom surface of the second outer periphery trench to the fifth semiconductor region exposed to the bottom surface of the third outer periphery trench. A clearance between the second and third outer periphery trenches is wider than each of a clearance between the first and second outer periphery trenches and a clearance between the third and fourth outer periphery trenches.

Abstract: An SiC semiconductor device has a p type region including a low concentration region and a high concentration region filled in a trench formed in a cell region. A p type column is provided by the low concentration region, and a p+ type deep layer is provided by the high concentration region. Thus, since a SJ structure can be made by the p type column and the n type column provided by the n type drift layer, an on-state resistance can be reduced. As a drain potential can be blocked by the p+ type deep layer, at turnoff, an electric field applied to the gate insulation film can be alleviated and thus breakage of the gate insulation film can be restricted. Therefore, the SiC semiconductor device can realize the reduction of the on-state resistance and the restriction of breakage of the gate insulation film.

Abstract: A FET incorporating a Schottky diode has a structure allowing the ratio of an area in which the Schottky diode is formed and an area in which the FET is formed to be freely adjusted. A trench extending for a long distance is utilized. Schottky electrodes are interposed at positions appearing intermittently in the longitudinal direction of the trench. By taking advantage of the growth rate of a thermal oxide film formed on SiC being slower, and the growth rate of a thermal oxide film formed on polysilicon being faster, a structure can be obtained in which insulating film is formed between gate electrodes and Schottky electrodes, between the gate electrodes and a source region, between the gate electrodes and a body region, and between the gate electrodes and a drain region, and in which insulating film is not formed between the Schottky electrodes and the drain region.

Abstract: A semiconductor device includes a semiconductor substrate including a trench, a gate insulating layer, and a gate electrode. A step is arranged in a side surface of the trench. The semiconductor substrate includes first and second regions, a body region, and a side region. The body region extends from a position being in contact with the first region to a position located on the lower side with respect to the step. The body region is in contact with the gate insulating layer at a portion of the upper side surface located on a lower side with respect to the first region. The second region is located on a lower side of the body region and in contact with the gate insulating layer at the lower side surface. The side region is in contact with the gate insulating layer at the step surface and connected to the second region.

Abstract: A semiconductor device provided herein includes a trench in which a gate insulating layer (GIL) and a gate electrode are located. A step is provided in a lateral surface of the trench. The step surface descends toward a center of the trench. First and second regions are of a first conductivity type. A body region, a lateral region and a bottom region are of a second conductivity type. The first region, a body region, and the second region are in contact with the GIL at the upper lateral surface of the trench. The second region is in contact with the GIL at the lower lateral surface of the trench. A lateral region is in contact with the GIL at the lower lateral surface. A bottom region is in contact with the GIL at the bottom surface of the trench.

Abstract: A semiconductor device includes a semiconductor substrate having a main cell region and a sense cell region. A separation trench separating a main second semiconductor region from a sense second semiconductor region is provided in an upper surface of the semiconductor substrate. The semiconductor substrate includes a separation fourth semiconductor region being of a second conductivity type and separated from the main second semiconductor region and the sense second semiconductor substrate by a third semiconductor region.

Abstract: A trench structure which is capable of promoting extension of a depletion layer and hardly causes thermal stress is provided. A semiconductor device includes a semiconductor substrate. A plurality of loop trenches is formed on the surface of the semiconductor substrate. Each loop trench is configured to extend so as to surround a region smaller than the region where a plurality of gate trenches is formed. Each loop trench is separated from other loop trenches. A second insulating layer is located in each loop trench. P-type fourth regions are formed in the semiconductor substrate. Each fourth region is in contact with a bottom surface of corresponding one of the loop trenches and is configured to extend along the corresponding one of the loop trenches.

Abstract: A semiconductor device has a semiconductor substrate including a body region, a drift region, a trench that extends from a surface of the semiconductor substrate into the drift region through the body region, and a source region located adjacent to the trench in a range exposed to the surface of the semiconductor substrate, the source region being isolated from the drift region by the body region. A specific layer is disposed on a bottom of the trench, and it has a characteristic of forming a depletion layer at a junction between the specific layer and the drift region. An insulating layer covers an upper surface of the specific layer and a sidewall of the trench. A conductive portion is formed on a part of the side wall of the trench. The conductive portion is joined to the specific layer, and reaches the surface of the semiconductor substrate.

Abstract: A semiconductor substrate of a semiconductor device includes a first conductive body region that is formed in the element region; a second conductive drift region that is formed in the element region; a gate electrode that is formed in the element region, that is arranged in a gate trench, and that faces the body region; an insulating body that is formed in the element region and is arranged between the gate electrode and an inside wall of the gate trench; a first conductive floating region that is formed in the element region and that is surrounded by the drift region; a first voltage-resistance retaining structure that is formed in the peripheral region and that surrounds the element region; and a gate pad that is formed in the peripheral region, and is electrically connected to the gate electrode in a position on the element region-side of the first voltage-resistance retaining structure.

Abstract: A semiconductor device includes: a drift layer having a first conductivity type; a body layer having a second conductivity type; a first semiconductor region having the first conductivity type; a gate insulation film; a trench gate electrode; a first main electrode; a second semiconductor region having the second conductivity type; and a conductor region. The first main electrode is electrically connected with the body layer and the first semiconductor region. The second semiconductor region is disposed on a bottom part of the gate trench, and is surrounded by the drift layer. The conductor region is configured to electrically connect the first main electrode with the second semiconductor region and is configured to equalize, when the semiconductor device is in an off-state, a potential of the second semiconductor region and a potential of the first main electrode.

Abstract: In a silicon carbide semiconductor device, a plurality of trenches has a longitudinal direction in one direction and is arranged in a stripe pattern. Each of the trenches has first and second sidewalls extending in the longitudinal direction. The first sidewall is at a first acute angle to one of a (11-20) plane and a (1-100) plane, the second sidewall is at a second acute angle to the one of the (11-20) plane and the (1-100) plane, and the first acute angle is smaller than the second acute angle. A first conductivity type region is in contact with only the first sidewall in the first and second sidewalls of each of the trenches, and a current path is formed on only the first sidewall in the first and second sidewalls.

Abstract: A semiconductor device 10 includes an element domain 40 and a termination domain 50 that surrounds the element domain 40. The element domain 40 and the termination domain 50 respectively include a second conductive type drift region 18. A gate trench 38 may be provided in the element domain 40. The termination domain 50 may be provided with a termination trench 22 surrounding the element domain. A first conductive type floating region surrounded by the drift region 18 is not provided at a bottom of the gate trench 38, and a first conductive type floating region 20 surrounded by the drift region 18 is provided at a bottom of the termination trench 22.

Abstract: A semiconductor device includes: a drift layer having a first conductivity type; a body layer having a second conductivity type; a first semiconductor region having the first conductivity type; a gate insulation film; a trench gate electrode; a first main electrode; a second semiconductor region having the second conductivity type; and a conductor region. The first main electrode is electrically connected with the body layer and the first semiconductor region. The second semiconductor region is disposed on a bottom part of the gate trench, and is surrounded by the drift layer. The conductor region is configured to electrically connect the first main electrode with the second semiconductor region and is configured to equalize, when the semiconductor device is in an off-state, a potential of the second semiconductor region and a potential of the first main electrode.

Abstract: A trench structure which is capable of promoting extension of a depletion layer and hardly causes thermal stress is provided. A semiconductor device includes a semiconductor substrate. A plurality of loop trenches is formed on the surface of the semiconductor substrate. Each loop trench is configured to extend so as to surround a region smaller than the region where a plurality of gate trenches is formed. Each loop trench is separated from other loop trenches. A second insulating layer is located in each loop trench. P-type fourth regions are formed in the semiconductor substrate. Each fourth region is in contact with a bottom surface of corresponding one of the loop trenches and is configured to extend along the corresponding one of the loop trenches.

Abstract: An SiC semiconductor device has a p type region including a low concentration region and a high concentration region filled in a trench formed in a cell region. A p type column is provided by the low concentration region, and a p+ type deep layer is provided by the high concentration region. Thus, since a SJ structure can be made by the p type column and the n type column provided by the n type drift layer, an on-state resistance can be reduced. As a drain potential can be blocked by the p+ type deep layer, at turnoff, an electric field applied to the gate insulation film can be alleviated and thus breakage of the gate insulation film can be restricted. Therefore, the SiC semiconductor device can realize the reduction of the on-state resistance and the restriction of breakage of the gate insulation film.

Abstract: A manufacturing method of a silicon carbide semiconductor device includes: forming a drift layer on a silicon carbide substrate; forming a base layer on or in a surface portion of the drift layer; forming a source region in a surface portion of the base layer; forming a trench to penetrate the base layer and to reach the drift layer; forming a gate electrode on a gate insulation film in the trench; forming a source electrode electrically connected to the source region and the base layer; and forming a drain electrode on a back surface of the substrate. The forming of the trench includes: flattening a substrate surface; and etching to form the trench after flattening.

Abstract: The present application relates to technology for improving a withstand voltage of a semiconductor device. The semiconductor device includes a termination area that surrounds a cell area. The cell area is provided with a plurality of main trenches. The termination area is provided with one or more termination trenches surrounding the cell area. A termination trench is disposed at an innermost circumference of one or more termination trenches. A body region is disposed on a surface of a drift region. Each main trench reaches the drift region. A gate electrode is provided within each main trench. The termination trench reaches the drift region. Sidewalls and a bottom surface of the termination trench are covered with a insulating layer. A surface of the insulating layer covering the bottom surface of the termination trench is covered with a buried electrode. A gate potential is applied to the buried electrode.

Abstract: A FET incorporating a Schottky diode has a structure allowing the ratio of an area in which the Schottky diode is formed and an area in which the FET is formed to be freely adjusted. A trench extending for a long distance is utilized. Schottky electrodes are interposed at positions appearing intermittently in the longitudinal direction of the trench. By taking advantage of the growth rate of a thermal oxide film formed on SiC being slower, and the growth rate of a thermal oxide film formed on polysilicon being faster, a structure can be obtained in which insulating film is formed between gate electrodes and Schottky electrodes, between the gate electrodes and a source region, between the gate electrodes and a body region, and between the gate electrodes and a drain region, and in which insulating film is not formed between the Schottky electrodes and the drain region.