Abstract: Provided is a semiconductor device comprising: a plurality of trench portions include a gate trench portion and a dummy trench portion; a first lower end region of a second conductivity type that is provided to be in contact with lower ends of two or more trench portions which include the gate trench portion; a well region of a second conductivity type that is arranged in a different location from the first lower end region in a top view, and a second lower end region of a second conductivity type that is provided between the first lower end region and the well region in a top view being separated from the first lower end region and the well region, and provided to be in contact with lower ends of one or more trench portions including the gate trench portion.

Abstract: Provided is a semiconductor device comprising a semiconductor substrate provided with a drift region of a first conductivity type, wherein the substrate includes: an active portion; and a trench portion provided in the active portion at an upper surface of the substrate, the active portion includes: a first region in which trench portions including the trench portion are arrayed at a first trench interval in an array direction; and a second region in which trench portions including the trench portion are arrayed at a second trench interval greater than the first trench interval in the array direction, the first region includes a first bottom region of a second conductivity type provided over bottoms of at least two trench portions of the trench portions, and the second region includes a second bottom region of the second conductivity type provided at a bottom of one trench portion of the trench portions.

Abstract: Provided is a semiconductor device comprising: a plurality of trench portions; a first lower end region of a second conductivity type that is provided to be in contact with lower ends of two or more trench portions which include the gate trench portion; a well region of the second conductivity type that is arranged in a different location from the first lower end region in a top view, and a second lower end region of the second conductivity type that is provided between the first lower end region and the well region in a top view being separated from the first lower end region and the well region, and provided to be in contact with lower ends of one or more trench portions including the gate trench portion.

Abstract: Provided is a semiconductor device including a transistor portion, in which the transistor portion has a drift region of a first conductivity type provided in a semiconductor substrate, a base region of a second conductivity type provided above the drift region, an accumulation region of the first conductivity type provided above the drift region, a plurality of trench portions provided to extend from a front surface of the semiconductor substrate to the drift region, and a trench bottom portion of the second conductivity type provided in bottom portions of the plurality of trench portions, and the accumulation region has a doping concentration with a half width of 0.3 ?m or more.

Abstract: A method of manufacturing a semiconductor device includes: forming a first trench from an upper surface side of a semiconductor substrate; burying the first trench with an insulated gate electrode structure; forming a base region at an upper part of the semiconductor substrate so as to be in contact with the first trench; forming a first main electrode region at an upper part of the base region so as to be in contact with the first trench; forming a second trench by removing a part of the first main electrode region; implanting first impurity ions entirely into a side wall surface of the second trench from a diagonally upper side; implanting second impurity ions into a bottom surface of the second trench to form a contact region at a bottom of the second trench; and forming a second main electrode region on a bottom surface side of the semiconductor substrate.

Abstract: Provided is a semiconductor device comprising: a semiconductor substrate including a drift region of a first conductivity type; a base region of a second conductivity type provided between the drift region and the upper surface of the semiconductor substrate; a plurality of trench portions provided from the upper surface of the semiconductor substrate to below the base region; a lower end region of the second conductivity type provided in contact with lower ends of two or more trench portions; a well region of the second conductivity type which is provided from the upper surface of the semiconductor substrate to below the base region, and has a higher doping concentration than the base region; and a high resistance region of the second conductivity type which is arranged between the lower end region and the well region in the top view and has a lower doping concentration than the lower end region.

Abstract: Provided is an insulated gate bipolar transistor including: a base region which is provided between an emitter region and a drift region; an accumulation region which is provided between a base region and a drift region, and which has a doping concentration higher than that of the drift region; a gate trench portion which is provided from an upper surface of a semiconductor substrate to a portion below the accumulation region; and a lower end region which is provide to be in contact with a lower end of the gate trench portion; wherein the accumulation region has a first concentration peak in which the doping concentration indicates a maximum value in a depth direction, and a distance between the first concentration peak and the lower end region in a depth direction is less than a distance between the first concentration peak and the base region in the depth direction.

Abstract: Provided is a semiconductor device including an active section having a transistor section and a diode section, and an edge termination structure section provided to an outer circumference of the active section, in which the transistor section has a drift region of a first conductivity type which is provided in a semiconductor substrate, a base region of a second conductivity type which is provided above the drift region, a trench portion extending from a front surface of the semiconductor substrate to the drift region, and a trench bottom portion of the second conductivity type which is provided in a lower end of the trench portion, and the diode section is provided between a transistor section in proximity to the edge termination structure section, and the edge termination structure section in a top view.

Abstract: Provided is a semiconductor device including: a first trench contact portion provided to an inside of a contact region; a second trench contact portion provided to an inside of an emitter region; a first plug portion of a second conductivity type, which is provided in contact with a lower end of the first trench contact portion and has a higher concentration than a base region; and a second plug portion of a second conductivity type, which is provided in contact with a lower end of the second trench contact portion, is provided to a position closer to a lower surface than the first plug portion, and has a higher concentration than the base region.

Abstract: Provided is a semiconductor device provided with a transistor section, the semiconductor device including a drift region of a first conductivity type which is provided in a semiconductor substrate, a plurality of trench portions extending from a front surface of the semiconductor substrate to the drift region, an emitter region of the first conductivity type which has a doping concentration higher than a doping concentration of the drift region and which is provided to extend from a trench portion to an adjacent trench portion among the plurality of trench portions on the front surface of the semiconductor substrate, and a trench bottom portion of a second conductivity type which is provided to a lower end of the trench portion, in which the transistor section has an electron passage region in which the trench bottom portion is not provided in a top view.

Abstract: Provided is a semiconductor device in which one mesa portion of two mesa portions in contact with a gate trench portion is an active mesa portion in which an emitter region of a first conductivity type having a doping concentration higher than that of a drift region is arranged in contact with the gate trench portion, the other mesa portion of two mesa portions in contact with the gate trench portion is a dummy mesa portion having no emitter region, and a dummy contact resistance which is a resistance of the dummy mesa portion and an emitter electrode is 1000 times or more as high as an active contact resistance which is a resistance of the active mesa portion and the emitter electrode.

Abstract: Provided is a semiconductor device comprising a semiconductor substrate, the semiconductor substrate comprising an active portion, a second conductivity type circumferential well region surrounding the active portion in a top view, and a trench portion provided in the active portion on an upper surface of the semiconductor substrate, wherein the active portion includes a center portion including a first conductivity type emitter region, and a circumferential portion surrounding the center portion, wherein the center portion includes a second conductivity type active side bottom region provided across bottoms of at least two of the trench portion, the circumferential portion includes a second conductivity type circumferential side bottom region electrically connected to the circumferential well region, facing the active side bottom region, and provided at the bottom of the trench portion, and the active side bottom region and the circumferential side bottom region are provided apart from each other.

Abstract: An intermediate station and method for facilitating handover in a multi-hop communications system is disclosed. The method may include receiving a handover trigger, finding a target station to receive handover, determining whether the handover requires a timing change, wherein if it is determined that a preamble and broadcast timing change for one or more downstream stations is required, estimating when the handover will take place, instructing the one or more downstream stations to resynchronize, and performing the handover to the target station.

Abstract: A mobile network domain (101) comprises a mobility anchor node (105) providing a non-mobile network attachment and at least a first and second access router (107, 109) supporting access by mobile nodes (127). The nodes of the mobile network domain (101) support label encapsulated tunneling. Label switching paths (121, 129) are established between the mobility anchor node (105) and the access routers (107, 109) as well as between the access routers (107, 109) themselves. When a handover of a mobile node (127) from the first access router (107) to the second access router (109) is detected, the first access router (107) forwards data packets for the mobile node (127) received via a first label switching path (121) to the second access router (109) via a direct label switching path (129) between the access routers (107, 109). The forwarded data packets are label encapsulated tunneling data packets.

Abstract: An intermediate station and method for facilitating handover in a multi-hop communications system is disclosed. The method may include receiving a handover trigger, finding a target station to receive handover, determining whether the handover requires a timing change, wherein if it is determined that a preamble and broadcast timing change for one or more downstream stations is required, estimating when the handover will take place, instructing the one or more downstream stations to resynchronize, and performing the handover to the target station.

Abstract: A wireless packet communication system that enables a wireless terminal to move from one wireless LAN to another while maintaining packet communication. The wireless terminal detects the electric field strength of a carrier signal from each base station during at least one back-off period, creates move destination information based on a carrier signal having the greatest electric field strength and the IP address of the currently used base station, and transmits the created Information and IP address to a server. The server writes the IP address of the wireless terminal into an edge router connected to a base station at the move destination in accordance with the information and IP address created by the wireless terminal to ensure that the packet data from a remote party is transmitted from the base station at the move destination.

Abstract: A method and apparatus for relaying data within a multi-hop communication system (200) is provided herein. During operation, all preamble (301, 305) and broadcast (303, 307) information for relaying nodes (201) and for the base station (204) is placed during a beginning portion (315) of a frame (300) prior to any data transmission (511, 609). By placing preamble/broadcast portions in the beginning of the frame, the data transmission portions of the frame can be allowed to vary in time, yet synchronization will be allowed between all nodes in the system.

Abstract: A base station (101) will instruct relay stations (102) to periodically skip transmissions of their control information when control messaging by all relay stations exceeds a predetermined threshold (e.g., 50% of radio resource capacity). The base station determines the relay stations to skip by periodically ranking the relay stations and skipping control messages for relay stations having a lowest rank.

Abstract: A wireless packet communication system that enables a wireless terminal to move from one wireless LAN to another while maintaining packet communication. The wireless terminal detects the electric field strength of a carrier signal from each base station during at least one back-off period, creates move destination information based on a carrier signal having the greatest electric field strength and the IP address of the currently used base station, and transmits the created Information and IP address to a server. The server writes the IP address of the wireless terminal into an edge router connected to a base station at the move destination in accordance with the information and IP address created by the wireless terminal to ensure that the packet data from a remote party is transmitted from the base station at the move destination.

Abstract: A communication system in which a mobile terminal MT communicates with a home agent HA by way of a cellular communication network and a WLAN includes a processor in communication with the HA and the cellular communication network. The MT communicates with the HA via the cellular communication network and the processor receives handover history information of the MT from the cellular communication network. As the MT moves within the cellular communication network, the processor predicts when the MT will enter an area covered by a WLAN and pre-registers the MT with the WLAN so that when the MT enters the WLAN covered area, the MT can immediately start receiving information from the WLAN. By having a processor perform the pre-registration, the radio resources of the MT are preserved.