Abstract: A semiconductor device includes an element to be protected formed on a semiconductor substrate, a first protection transistor, and a second protection transistor. The first protection transistor is formed on a first well of a first conductivity type formed in an upper portion of a deep well of a second conductivity type. The second protection transistor is formed on a second well of the second conductivity type. A second source/drain diffusion layer is electrically connected with a third source/drain diffusion layer and at the same potential as the first well. A fourth source/drain diffusion layer is electrically connected with a second diffusion layer and at the same potential as the second well and the second diffusion layer.

Abstract: A semiconductor device is provided. In an embodiment, the device includes a substrate and a transistor formed on the substrate. The transistor may include a gate structure, a source region, and a drain region. The drain region includes an alternating-doping profile region. The alternating-doping profile region may include alternating regions of high and low concentrations of a dopant. In an embodiment, the transistor is a high voltage transistor.

Abstract: The present invention provides a method for fabricating a MOS transistor (100) with suppression of edge transistor effect. In one embodiment of an NMOS, an elongate implant limb (110, HOa, 114) extends from each of two sidewalls (14a, 14b) of a p-type well (14) to partially wrap around each respective longitudinal end of the gate (20) and to overlay a portion thereof. In another embodiment, the elongate implant limb (110, 110a) extends into the drain/source drift region (32, 42). The NMOS transistor (100) thus fabricated allows the NMOS transistor to operate at relatively high voltages with reduced drain leakage current but with no additional masks or process time in the process integration.

Abstract: A semiconductor device in which: reed-shaped portions of an emitter layer of a second conductivity type are discretely formed on a surface of a base layer in a first vertical direction that is a direction vertical to a direction from an emitter electrode to a collector electrode; in a region adjoining the emitter layer, an interface of the contact layer on a side of the collector electrode is formed up to directly beneath an interface of the gate electrode on a side of the emitter electrode; and directly beneath the emitter layer, the interface of the contact layer on the side of the collector electrode is formed closer to the emitter electrode than to the interface of the gate electrode on the side of the emitter electrode.

Abstract: A structure and method of fabricating the structure. The structure including: a dielectric isolation in a semiconductor substrate, the dielectric isolation extending in a direction perpendicular to a top surface of the substrate into the substrate a first distance, the dielectric isolation surrounding a first region and a second region of the substrate, a top surface of the dielectric isolation coplanar with the top surface of the substrate; a dielectric region in the second region of the substrate; the dielectric region extending in the perpendicular direction into the substrate a second distance, the first distance greater than the second distance; and a first device in the first region and a second device in the second region, the first device different from the second device, the dielectric region isolating a first element of the second device from a second element of the second device.

Abstract: A semiconductor device includes a gate electrode over a semiconductor substrate, wherein the gate electrode has a gate width direction; a source/drain region in the semiconductor substrate and adjacent the gate electrode, wherein the source/drain region has a first width in a direction parallel to the gate width direction; and a bulk pick-up region in the semiconductor substrate and abutting the source/drain region. The bulk pick-up region and the source/drain region have opposite conductivity types. The bulk pick-up region has a second width in the width direction, and wherein the second width is substantially less than the first width.

Abstract: In the semiconductor device according to the present invention, a P type diffusion layer and an N type diffusion layer as a drain lead region are formed on an N type diffusion layer as a drain region. The P type diffusion layer is disposed between a source region and the drain region of the MOS transistor. When a positive ESD surge is applied to a drain electrode, causing an on-current of a parasite transistor to flow, this structure allows the on-current of the parasite transistor to take a path flowing through a deep portion of an epitaxial layer. Thus, the heat breakdown of the MOS transistor is prevented.

Abstract: One embodiment relates to an integrated circuit that includes a lateral trench MOSFET disposed in a semiconductor body. The lateral trench MOSFET includes source and drain regions having a body region therebetween. A gate electrode region is disposed in a trench that extends beneath the surface of the semiconductor body at least partially between the source and drain. A gate dielectric separates the gate electrode region from the semiconductor body. In addition, a field plate region in the trench is coupled to the gate electrode region, and a field plate dielectric separates the field plate region from the semiconductor body. Other integrated circuits and methods are also disclosed.

Abstract: An electrostatic discharge failure protective element (50) is provided with second conductivity type source region (4) and drain region (5), which are formed at a prescribed interval to sandwich a channel region (3) on the surface of a first conductivity type semiconductor substrate (1); a first conductivity type well region (7) formed to cover the source region; a second conductivity type buried layer (8) formed below the first conductivity type well region; a second conductivity type first impurity region (9a) formed between the drain region and the buried layer to constitute a current path; and a second conductivity type second impurity region (9b) to isolate the well region and the semiconductor substrate one from the other.

Abstract: A semiconductor device includes a semiconductor substrate of a first conductivity type, a first semiconductor region of the first conductivity type on the semiconductor substrate, and a plurality of second semiconductor regions of a second conductivity type disposed separately in the first semiconductor region. A difference between a charge quantity expressed by an integral value of a net activated doping concentration in the second semiconductor regions in the surface direction of the semiconductor substrate and a charge quantity expressed by an integral value of a net activated doping concentration in the first semiconductor region in the surface direction of the semiconductor substrate is always a positive quantity and becomes larger from the depth of the first junction plane to a depth of a second junction plane on an opposite side from the first junction plane.

Abstract: A manufacturing method of a semiconductor device including an LDMOS transistor includes: a process (a) of forming a first conductive well diffusion layer in the semiconductor substrate; a process (b) of sequentially forming a gate insulator film, a gate conductive film, and a photoresist film on a region on the semiconductor substrate corresponding to the well diffusion layer; a process (c) of performing photolithography to remove a part of the photoresist film formed in a predetermined region, and etching the gate conductive film using a remaining part of the photoresist film as a mask so as to form an opening in the predetermined region; a process (d) of doping second conductive impurity ions using a remaining part of the gate conductive film and the remaining part of the photoresist film as a mask so as to form the body layer; and a process (e) of removing the remaining part of the gate conductive film except a part corresponding to the gate electrode formed based on a part that constitutes a lateral surfa

Abstract: A semiconductor device where a plurality of DMOS transistors formed in a distributed manner on a semiconductor substrate can operate without being destroyed and a method of manufacturing the same. The on/off threshold voltage of a DMOS transistor at the innermost position from among three or more DMOS transistors formed in a distributed manner on a semiconductor is greater than the on/off threshold voltage of a DMOS transistor at the outermost position.

Abstract: A semiconductor device, includes: a semiconductor layer including a first semiconductor region of a first conductivity type and a second semiconductor region of the first conductivity type, the second semiconductor region having a first conductivity type impurity concentration lower than a first conductivity type impurity concentration of the first semiconductor region; a source region of a second conductivity type provided on the first semiconductor region; a drain region of the second conductivity type provided on the second semiconductor region; an insulating film provided on the semiconductor layer between the source region and the drain region; a gate electrode provided on the insulating film; and a drift region of the second conductivity type provided in a surface side portion of the semiconductor layer between the gate electrode and the drain region, the drift region being in contact with the drain region and having a second conductivity type impurity concentration lower than a second conductivity type

Abstract: The invention includes a laterally double-diffused metal-oxide semiconductor (LDMOS) having a reduced size, a high breakdown voltage, and a low on-state resistance. This is achieved by providing a thick gate oxide on the drain side of the device, which reduces electric field crowding in the off-state to reduce the breakdown voltage and forms an accumulation layer in the drift region to reduce the device resistance in the on-state. A version of the device includes a low voltage version with a thin gate oxide on the source side of the device and a high voltage version of the device includes a thick gate oxide on the source side. The LDMOS may be configured in an LNDMOS having an N type source or an LPDMOS having a P type source. The source of the device is fully aligned under the oxide spacer adjacent the gate to provide a large SOA and to reduce the device leakage.

Abstract: Disclosed are lateral double diffused metal oxide semiconductor (LDMOS) transistors having a uniform threshold voltage and methods for manufacturing the same. The methods include forming a polysilicon layer over the semiconductor substrate including a shallow trench isolation region, etching a portion of the polysilicon layer over an active region, implanting first conductive-type impurity ions using the polysilicon layer as a mask to form a first conductive-type body region, implanting second conductive-type impurity ions using the polysilicon layer as a mask to form a second conductive-type channel region in the first conductive-type body region, removing the polysilicon layer, forming gate electrodes in the polysilicon-free region, and forming a source region and a drain region in the first conductive-type body region using the gate electrode and the shallow trench isolation as ion-implantation masks.

Abstract: A semiconductor includes a high voltage region formed in a substrate, first and second drift regions formed in the high voltage region, an isolation layer in the high voltage region, a gate formed on and/or over the first and second drift regions, and a drain and a source formed in the first drift region and the second drift region.

Abstract: A semiconductor device includes: an active region defined by a device isolation layer on and/or over a substrate; a second conductive well on and/or over the active region; an extended drain formed at one side of the second conductive well; a gate electrode on and/or over the second conductive well and the extended drain; and a source and a drain formed at both sides of the gate electrode, in which extended regions are formed at the corners of the second conductive well under the gate electrode.

Abstract: A semiconductor package may comprise a semiconductor substrate, a MOSFET device having a plurality cells formed on the substrate, and a source region common to all cells disposed on a bottom of the substrate. Each cell comprises a drain region on a top of the semiconductor device, a gate to control a flow of electrical current between the source and drain regions, a source contact proximate the gate; and an electrical connection between the source contact and source region. At least one drain connection is electrically coupled to the drain region. Source, drain and gate pads are electrically connected to the source region, drain region and gates of the devices. The drain, source and gate pads are formed on one surface of the semiconductor package. The cells are distributed across the substrate, whereby the electrical connections between the source contact of each device and the source region are distributed across the substrate.

Abstract: A semiconductor device which may be for a high voltage and a method of manufacturing the same. A semiconductor device may include a first conductivity-type well formed on and/or over a substrate, a second conductivity-type drift region formed on and/or over a first conductivity-type well, an isolation layer formed on and/or over a first conductivity-type well, an isolation layer defining an isolation region and/or an active region, a gate pattern formed on and/or over a predetermined upper surface of a second conductivity-type drift region and/or a first conductivity-type well at an active region of a substrate, and/or second conductivity-type source and/or drain regions formed on and/or over second conductivity-type drift regions at two sides of a gate pattern. A gate pattern and/or a drift region of a semiconductor device may be formed substantially without gaps.

Abstract: A semiconductor device includes an isolation layer formed on and/or over a semiconductor substrate to define an isolation layer, a drift area formed in an active area separated by the isolation layer, a pad nitride layer pattern formed in a form of a plate on the drift area, and a gate electrode having step difference between lateral sides thereof due to the pad nitride layer pattern.

Abstract: A voltage converter includes an output circuit having a high-side device and a low-side device which can be formed on a single die (a “PowerDie”). The high-side device can include a lateral diffused metal oxide semiconductor (LDMOS) while the low-side device can include a planar vertical diffused metal oxide semiconductor (VDMOS). The voltage converter can further include a controller circuit on a different die which can be electrically coupled to, and co-packaged with, the power die.

Abstract: A semiconductor device includes a semiconductor substrate, a gate formed over the semiconductor substrate, a source region formed in the semiconductor substrate at one side of the gate, a drain region formed in the semiconductor substrate at another side of the gate, and a channel region formed between the source region and the drain region, the channel region including a first channel region having a first threshold voltage and a second channel region having a second threshold voltage higher than the first threshold voltage. Accordingly, the semiconductor device has two channel regions having different threshold voltages.

Abstract: A device for protecting a semiconductor device from electrostatic discharge may include a high voltage first conductivity type well formed in a semiconductor substrate. A first stack region may have a first conductivity type drift region, and a first conductivity type impurity region stacked in succession in the high voltage first conductivity type well. A second stack region may have a second conductivity type drift region, and a second conductivity type impurity region stacked in succession in the high voltage first conductivity type well. A device isolating film formed between the first stack region and the second stack region for isolating the first stack region from the second stack region.

Abstract: A metal oxide semiconductor device comprising a substrate, at least an isolation structure, a deep N-type well, a P-type well, a gate, a plurality of N-type extension regions, an N-type drain region, an N-type source region and a P-type doped region is provided. The N-type extension regions are disposed in the substrate between the isolation structures and either side of the gate, while the N-type drain region and the N-type source region are respectively disposed in the N-type extension regions at both sides of the gate. The P-type well surrounds the N-type extension regions, and the P-type doped region is disposed in the P-type well of the substrate and is isolated from the N-type source region by the isolation structure.

Abstract: For achieving an enhanced combination of a low on-resistance at a high break-through voltage a lateral high-voltage MOS transistor comprises a plurality of doped RESURF regions of the first conductivity type within the drift region, wherein the doped RESURF regions are separated from each other by drift region sections in a first lateral direction (y), which is parallel to a substrate surface and is orthogonal to a connecting line from the source region to the drain region, and also in a depth direction, which is orthogonal to the substrate surface, such that in each of said two directions an alternating arrangement of regions of the first and second conductivity types is provided.

Abstract: Disclosed are a semiconductor device and a method of manufacturing the same. The semiconductor device includes a substrate formed therein with a first conductive type well, and an LDMOS device formed on the substrate. The LDMOS device includes a gate electrode, gate oxides formed below the gate electrode, a source region formed in the substrate at one side of the gate electrode, and a drain region formed in the substrate at an opposite side of the gate electrode. The gate oxide includes first and second gate oxides disposed side-by-side and having thicknesses different from each other.

Abstract: One embodiment of inventive concepts exemplarily described herein may be generally characterized as a semiconductor device including an isolation region within a substrate. The isolation region may define an active region. The active region may include an edge portion that is adjacent to an interface of the isolation region and the active region and a center region that is surrounded by the edge portion. The semiconductor device may further include a gate electrode on the active region and the isolation region. The gate electrode may include a center gate portion overlapping a center portion of the active region, an edge gate portion overlapping the edge portion of the active region, and a first impurity region of a first conductivity type within the center gate portion and outside the edge portion. The semiconductor device may further include a gate insulating layer disposed between the active region and the gate electrode.

Abstract: An LDMOS device and method for making the same are disclosed. The LDMOS device comprises a first well, a second well, a third well, a first ion implantation region, and a second ion implantation region. The first well is in a semiconductor substrate. The second well is in the first well. The third well is first well adjacent to the second well. The first ion implantation region is in the second well. The second ion implantation region is in the third well. A device isolation layer structure between a P-type well region and a P-type body of the LDMOS device may be eliminated, thereby preventing a reduction in the doping concentration of the P-type well, thus minimizing leakage current and maintaining a high breakdown voltage.

Abstract: A semiconductor device and a method of manufacturing the same are disclosed. The method includes forming ion impurity regions of a first conductivity type by forming a trench in a semiconductor substrate and implanting impurity ions into a lower portion of the trench at different depths; forming an oxide region in the substrate adjacent to one end of the trench; forming a device isolation film filling the trench; forming a high voltage well in the substrate and a second conductivity type body in the high voltage well; forming a gate on the semiconductor substrate partially overlapping the device isolation film; forming second well in the semiconductor substrate at one side of the device isolation film overlapping the ion diffusion regions and the oxide region; and forming source regions in the body and a drain region in the second well.

Abstract: A semiconductor device and a method of manufacturing a semiconductor device. A semiconductor device may include an epitaxial layer over a semiconductor substrate, a first well region over a epitaxial layer, a first isolation layer and/or a third isolation layer at opposite sides of said first well region and/or a second isolation layer over a first well region between first and third isolation layers. A semiconductor device may include a gate over a second isolation layer. A semiconductor device may include a second well region over a first well region between a third isolation layer and a gate, a first ion-implanted region over a second well region between a third isolation layer and a gate, and/or a second ion-implanted region between a first ion-implanted region and a gate. A semiconductor device may include an accumulation channel between a second well region and a gate.

Abstract: A LDMOS transistor having a channel region located between an outer boundary of an n-type region and an inner boundary of a p-body region. A width of the LDMOS channel region is less than 80% of a distance between an outer boundary of an n+-type region and the inner boundary of a p-body region. Also, a method for making a LDMOS transistor where the n-type dopants are implanted at an angle that is greater than an angle used to implant the p-type dopants. Furthermore, a VDMOS having first and second channel regions located between an inner boundary of a first and second p-body region and an outer boundary of an n-type region of the first and second p-body regions. The width of the first and second channel regions of the VDMOS is less than 80% of a distance between the inner boundary of the first and second p-body regions and an outer boundary of an n+-type region of the first and second p-body regions.

Abstract: The transistor comprises a source and a drain separated by a lightly doped intermediate zone. The intermediate zone forms first and second junctions respectively with the source and with the drain. The transistor comprises a first gate to generate an electric field in the intermediate zone, on the same side as the first junction, and a second gate to generate an electric field in the intermediate zone, on the same side as the second junction.

Abstract: A transistor is formed inside an isolation structure which includes a floor isolation region and a trench extending from the surface of the substrate to the floor isolation region. The trench may be filled with a dielectric material or may have a conductive material in a central portion with a dielectric layer lining the walls of the trench.

Abstract: A semiconductor device and a manufacturing method for the same are disclosed. The semiconductor device includes a gate pattern formed at an upper part of the semiconductor substrate to overlap one side of a drift region, and a shallow oxide region disposed adjacent to the gate pattern, having a shallower depth than a plurality of device isolation layers.

Abstract: According to an exemplary embodiment, a MOS transistor, such as an LDMOS transistor, includes a gate having a first side situated immediately adjacent to at least one source region and at least one body tie region. The MOS transistor further includes a drain region spaced apart from a second side of the gate. The MOS transistor further includes a body region in contact with the at least one body tie region, where the at least one body tie region is electrically connected to the at least one source region. The MOS transistor further includes a lightly doped region separating the drain region from the second side of the gate. The lightly doped region can isolate the body region from an underlying substrate.

Abstract: A lateral DMOS device includes a body diode region and a protective diode region. The body diode region has a second conduction type well region formed in a first conduction type semiconductor substrate, the second conduction type well region including a first conduction type body region and a drain region each formed in the second conduction type well region, a first conduction type impurity region and a source region formed in the first conduction type body region, and a gate insulating film and a gate electrode formed on the first conduction type semiconductor substrate. The first conduction type body region and the second conduction type well region compose a body diode. In the protective diode region, the first conduction type impurity region is formed at a prescribed interval and the first conduction type body region and the second conduction type well region compose a protective diode.

Abstract: In a semiconductor chip in which LDMOSFET elements for power amplifier circuits used for a power amplifier module are formed, a source bump electrode is disposed on an LDMOSFET formation region in which a plurality of source regions, a plurality of drain regions and a plurality of gate electrodes for the LDMOSFET elements are formed. The source bump electrode is formed on a source pad mainly made of aluminum via a source conductor layer which is thicker than the source pad and mainly made of copper. No resin film is interposed between the source bump electrode and the source conductor layer.

Abstract: A pseudo-drain MOS transistor is disclosed. The transistor includes a semiconductor substrate; a gate structure disposed on the semiconductor substrate; a source, a pseudo-drain, a drain, and a shallow trench isolation disposed in the semiconductor substrate, a p-well disposed in the semiconductor substrate and under the source and the gate structure; and an n-well disposed under the drain. The source and the pseudo-drain are disposed adjacent to two sides of the gate structure and the shallow trench isolation is disposed between the pseudo-drain and the drain, and the n-well is extended toward the pseudo-drain while not reaching the area below the gate structure.

Abstract: A method of manufacturing a semiconductor device, has forming a gate insulating film over a surface of a substrate, eliminating a portion of the gate insulating film in a region, forming a gate electrode over the gate insulating film and a drain electrode on the region, implanting first impurities into the substrate using the gate electrode and the drain electrode as a mask, forming an insulating film to fill the space between the gate electrode and the drain electrode, and implanting second impurities into the substrate to form a source region using the gate electrode, the drain electrode and the insulating film as a mask.

Abstract: A low Rdson LDMOS transistor having a shallow field oxide region that separates a gate electrode of the transistor from a drain diffusion region of the transistor. The shallow field oxide region is formed separate from the field isolation regions (e.g., STI regions) used to isolate circuit elements on the substrate. Fabrication of the shallow field oxide region is controlled such that this region extends below the upper surface of the semiconductor substrate to a depth that is much shallower than the depth of field isolation regions. For example, the shallow field oxide region may extend below the upper surface of the substrate by only Angstroms or less. As a result, the current path through the resulting LDMOS transistor is substantially unimpeded by the shallow field oxide region, resulting in a low on-resistance.

Abstract: An inventive semiconductor device includes a semiconductor layer, a source region provided in a surface layer portion of the semiconductor layer, a drain region provided in the surface of the semiconductor layer in spaced relation from the source region, a gate insulation film provided in opposed relation to a portion of the surface of the semiconductor layer present between the source region and the drain region, a gate electrode provided on the gate insulation film, and a drain-gate isolation portion provided between the drain region and the gate insulation film for isolating the drain region and the gate insulation film from each other in non-contact relation.

Abstract: Methods of making, structures, devices, and/or applications for lateral double-diffused metal oxide semiconductor (LDMOS) transistors are disclosed. In one embodiment, an LDMOS transistor can include: (i) an n-doped deep n-well (DNW) region on a substrate; (ii) a gate oxide and a drain oxide between a source region and a drain region of the LDMOS transistor, the gate oxide being adjacent to the source region, the drain oxide being adjacent to the drain region; (iii) a conductive gate over the gate oxide and a portion of the drain oxide; (iv) a p-doped p-body region in the source region; (v) an n-doped drain region in the drain region; (vi) a first n-doped n+ region and a p-doped p+ region adjacent thereto in the p-doped p-body region of the source region; and (vii) a second n-doped n+ region in the drain region.

Abstract: A DMOS transistor is fabricated with its source/body/deep body regions formed on the walls of a first set of trenches, and its drain regions formed on the walls of a different set of trenches. A gate region that is formed in a yet another set of trenches can be biased to allow carriers to flow from the source to the drain. Lateral current low from source/body regions on trench walls increases the active channel perimeter to a value well above the amount that would be present if the device was fabricated on just the surface of the wafer. Masking is avoided while open trenches are present. A transistor with a very low on-resistance per unit area is obtained.

Abstract: A lateral high-voltage device in which conductive trench plates are inserted across the voltage-withstand region, so that, in the on state, the current density vectors have less convergence. This can help reduce on-resistance.

Abstract: A planar extended drain transistor (100) is provided which comprises a control gate (102), a drain region (109), a channel region (107), and a drift region (108), wherein the drift region (108) is arranged between the channel region (107) and the drain region (109). Furthermore, the control gate (102) is at least partially buried into the channel region (107) and the drift region (108) comprises a doping material density which is lower than the doping material density of the drain region (109).

Abstract: A body layer of a first conductivity type is formed on a semiconductor substrate, and a source layer of a second conductivity type is formed in a surface region of the body layer. An offset layer of the second conductivity type is formed on the semiconductor substrate, and a drain layer of the second conductivity type is formed in a surface region of the offset layer. An insulating film is embedded in a trench formed in the surface region of the offset layer between the source layer and the drain layer. A gate insulating film is formed on the body layer and the offset layer between the source layer and the insulating film. A gate electrode is formed on the gate insulating film. A first peak of an impurity concentration profile in the offset layer is formed at a position deeper than the insulating film.

Abstract: An isolation area (10) is provided over a drift region (12) with a spacing (d) to a contact area (4) provided for a drain connection (D). The isolation area is used as an implantation mask, in order to produce a dopant profile of the drift region in which the dopant concentration increases toward the drain. The implantation of the dopant can be performed instead before the production of the isolation area, and the later production of the isolation area (10) changes the dopant profile also in a way that the dopant concentration increases toward the drain.

Abstract: A semiconductor device is formed having a trench adjacent to a current carrying region of the device. The trench is formed having a depth greater than the depth of a tub region of the device. Increasing the trench depth moves a region of higher field strength from the tub region to a region along the trench. The region along the trench does not have a junction and may withstand the higher field strength.

Abstract: A semiconductor device includes a first conductivity-type deep well formed in a substrate, a plurality of device isolation layers formed in the substrate in which the first conductivity-type deep well is formed, a second conductivity-type well formed on a portion of the first conductivity-type deep well between two of the device isolation layers, a first gate pattern formed over a portion of the second conductivity-type well, a second gate pattern formed over one of the device isolation layers, a source region formed in an upper surface of the second conductivity-type well to adjoin a first side of the first gate pattern, a first drain region formed to include the interface between an upper surface of the second conductivity-type well adjoining a second side of the first gate pattern and an upper surface of the first conductivity-type deep well adjoining the second side of the first gate pattern, and a second drain region formed in an upper surface of the first conductivity-type deep well to be spaced from th

Abstract: There is provided a semiconductor device including a field effect transistor. The field effect transistor includes a p-type low concentration region formed over a surface of a substrate, an n-type drain-side diffusion region and an n-type source-side diffusion region formed over a surface of the p-type low concentration region, an element isolation insulating layer, and another element isolation insulating layer. A p-type high concentration region, which has an impurity concentration higher than the impurity concentration of the p-type low concentration region, is formed below the n-type source-side diffusion region in the p-type low concentration region over a range at least from one end, which is opposite to the other end facing to the channel region, of the source-side diffusion region to one end, which is facing to the channel region, of the second element isolation insulating layer, when seen in a plan view.