In an insulated-gate type semiconductor device in which a gate-purpose conductive layer is embedded into a trench which is formed in a semiconductor substrate, and a source-purpose conductive layer is provided on a major surface of the semiconductor substrate, a portion of a gate pillar which is constituted by both the gate-purpose conductive layer and a cap insulating film for capping an upper surface of the gate-purpose conductive layer is projected from the major surface of the semiconductor substrate; a side wall spacer is provided on a side wall of the projected portion of the gate pillar; and the source-purpose conductive layer is connected to a contact region of the major surface of the semiconductor substrate, which is defined by the side wall spacer.

A semiconductor body having first and second vertically spaced apart surfaces is formed. A gate trench that vertically extends from the first surface of the semiconductor body towards the second surface is formed. A gate electrode and a gate dielectric are formed in the gate trench. The gate dielectric electrically insulates the gate electrode from adjacent semiconductor material. A doped superjunction region vertically extending from a bottom of the gate trench towards the second surface of the semiconductor body is formed. The doped superjunction region includes first, second, and third doped pillars vertically extending from the first surface of the first semiconductor layer and directly adjoining one another. The second pillar is laterally centered between the first and third pillars and has an opposite conductivity type as the first and third pillars.

Super-junction MOSFETs by trench fill system requires void-free filling epitaxial growth. This may require alignment of plane orientations of trenches in a given direction. Particularly, when column layout at chip corner part is bilaterally asymmetrical with a diagonal line between chip corners, equipotential lines in a blocking state are curved at corner parts due to column asymmetry at chip corner. This tends to cause points where equipotential lines become dense, which may cause breakdown voltage reduction. In the present invention, in power type semiconductor active elements such as power MOSFETs, a ring-shaped field plate is disposed in chip peripheral regions around an active cell region, etc., assuming a nearly rectangular shape. The field plate has an ohmic-contact part in at least a part of the portion along the side of the rectangle. However, in the portion corresponding to the corner part of the rectangle, an ohmic-contact part is not disposed.

A semiconductor device includes a semiconductor substrate having a drift region, and an edge terminal structure portion provided between the active region and an end portion of the semiconductor substrate on an upper surface of the semiconductor substrate. The edge terminal structure portion includes a plurality of guard rings of a second conductivity type which are in contact with the upper surface, and a high concentration region of the first conductivity type which has a higher doping concentration than the drift region and is provided, between adjacent two of the guard rings, from a position shallower than lower ends of the guard rings to a position deeper than the lower ends of the guard rings. Each of the guard rings has a region that is not covered by the high concentration region as viewed from a lower surface side.

An electronic device including a substrate, a semiconductor element disposed on the substrate, and a plurality of guard rings at least partially surrounding the semiconductor element, wherein adjacent guard rings are spaced apart by a substantially uniform distance as measured along an entire length of the guard rings, and at least one of the plurality of guard rings has a flared portion. In an embodiment, at least one of the plurality of guard rings electrically floats. In another embodiment, the plurality of guard rings are disposed at least partially below a primary surface of the substrate. In an embodiment, the electronic device is a high voltage MOSFET or an IGBT.

A problem associated with n-channel power MOSFETs and the like that the following is caused even by relatively slight fluctuation in various process parameters is solved: source-drain breakdown voltage is reduced by breakdown at an end of a p-type body region in proximity to a portion in the vicinity of an annular intermediate region between an active cell region and a chip peripheral portion, arising from electric field concentration in that area. To solve this problem, the following measure is taken in a power semiconductor device having a superjunction structure in the respective drift regions of a first conductivity type of an active cell region, a chip peripheral region, and an intermediate region located therebetween: the width of at least one of column regions of a second conductivity type comprising the superjunction structure in the intermediate region is made larger than the width of the other regions.

A semiconductor device includes a semiconductor substrate, a fin-shaped structure, a gate structure, a first doped region, a second doped region, and an intermediate region. The fin-shaped structure is disposed on and extends upwards from a top surface of the semiconductor substrate in a vertical direction. The gate structure is disposed straddling a part of the fin-shaped structure. At least a part of the first doped region is disposed in the fin-shaped structure. The second doped region is disposed in the fin-shaped structure and disposed above the first doped region in the vertical direction. The intermediate region is disposed in the fin-shaped structure. The second doped region is separated from the first doped region by the intermediate region, and a bottom surface of the gate structure is lower than or coplanar with a top surface of the first doped region in the vertical direction.

A semiconductor device includes a semiconductor layer, having an active region, in which a functional element is formed, a first impurity region of a first conductivity type, formed at a surface layer portion of the semiconductor layer, a second impurity region of a second conductivity type, formed at a surface layer portion of the first impurity region and defining the active region, and a well region of the second conductivity type, formed along a periphery of the second impurity region at the surface layer portion of the first impurity region and having an inner side edge portion positioned at the second impurity region side, and an outer side edge portion positioned at an opposite side with respect to the second impurity region and having a second conductivity type impurity concentration lower than a second conductivity type impurity concentration of the inner side edge portion.

An integrated circuit contains a logic MOS transistor and a memory MOS transistor of a same polarity. The logic MOS transistor has a logic channel stop layer. The memory MOS transistor has a memory channel stop layer. An average dopant density of the memory channel stop layer is higher than an average dopant density of the logic channel stop layer. The integrated circuit is formed by forming a global mask which exposes both the logic and memory MOS transistors. A global channel stop dose of dopants is implanted in the logic and memory MOS transistors. A memory mask is formed which exposes the memory MOS transistor and covers the logic MOS transistor. A memory channel stop dose of dopants of the same polarity is implanted into the memory MOS transistors. The memory channel stop dose of dopants are blocked from the logic MOS transistors.

A semiconductor device includes a substrate; a well of a first conductivity-type and including an anti-punch-through (APT) layer of the first conductivity-type; source and drain features of a second conductivity-type over the APT layer; a strap feature of the first conductivity-type over the well; multiple vertically-stacked channel layers over the APT layer and connecting the source and drain features; a gate wrapping around each channel layer; source and drain contacts electrically coupled to the source and drain features; source and drain vias landed on the source and drain contacts; a strap contact electrically coupled to the strap feature; and a strap via landed on the strap contact. The source via and the strap via are configured to be coupled to different voltages during a non-active mode of the semiconductor device and to be coupled to a substantially same voltage during an active mode of the semiconductor device.