A Laterally Diffused Metal Oxide Semiconductor (LDMOS) transistor with implant alignment spacers includes a gate stack comprising a first nitride layer. The first nitride layer is formed on a silicon layer. The gate stack is separated from a substrate by a first oxide layer. The gate stack includes a polysilicon layer formed from the silicon layer, and a second oxide layer is formed on a sidewall of the polysilicon layer. A drain region of the LDMOS transistor is implanted with a first implant aligned to a first edge formed by the second oxide layer. A second nitride layer conformingly covers the second oxide layer. A nitride etch-stop layer conformingly covers the second nitride layer.

A method of manufacturing a semiconductor device includes: forming a trench in a first side of a semiconductor layer, the semiconductor layer including a drift zone of a first conductivity; forming a drain region of the first conductivity type in the first side of the semiconductor layer and laterally adjoining the drift zone; forming a body region of a second conductivity type opposite the first conductivity type and laterally adjoining the drift zone at a side of the drift zone opposite the drain region; and forming source regions of the first conductivity type and body contact regions of the second conductivity type in a sidewall of the trench and arranged in an alternating manner along a length of the trench, using a dopant diffusion process which includes diffusing dopants of both conductivity types from oppositely-doped dopant source layers which are in contact with different regions of the sidewall.

The present disclosure relates to semiconductor devices, and more particularly, to high voltage extended drain MOSFET (EDMOS) devices in a high-k metal gate (HKMG) and methods of manufacture. A structure of the present disclosure includes a plurality of extended drain MOSFET (EDMOS) devices on a high voltage well with a split-gate dielectric material including a first gate dielectric material and a second gate dielectric material, the second gate dielectric material including a thinner thickness than the first gate dielectric material, and a high-k dielectric material on the split-gate dielectric material.

A semiconductor device includes a first semiconductor region having a first conductivity type and a second semiconductor region having a second conductivity type, a source region and a body contact region in the second semiconductor region. The semiconductor device also includes a channel region, in the second semiconductor region, located laterally between the source region and the first semiconductor region, a gate dielectric layer overlying both the channel region and a portion of the first semiconductor region, and a gate electrode overlying the gate dielectric layer. The semiconductor device further includes a conformal conductive layer covering an upper surface of the body contact region and a side surface of the source region.

A semiconductor device includes: a semiconductor layer of a first conductivity-type; a well region of a second conductivity-type provided at an upper part of the semiconductor layer; a base region of the second conductivity-type provided at an upper part of the well region; a carrier supply region of the first conductivity-type provided at an upper part of the base region; a drift region of the first conductivity-type provided separately from the base region; a carrier reception region of the first conductivity-type provided at an upper part of the drift region; a gate electrode provided on a top surface of the well region interposed between the base region and the drift region via a gate insulating film; and a punch-through prevention region of the second conductivity-type provided at the upper part of the well region and having an impurity concentration different from the impurity concentration of the base region.

The Rds*Cgd figure of merit (FOM) of a laterally diffused metal oxide semiconductor (LDMOS) transistor is improved by forming the drain drift region with a number of dopant implants at a number of depths, and forming a step-shaped back gate region with a number of dopant implants at a number of depths to adjoin the drain drift region.

The present disclosure relates to a semiconductor structure that includes a well region and a semiconductor substrate. The well region is disposed within the semiconductor substrate. The well region includes a plurality of first regions separated by a plurality of second regions, where the plurality of first regions is of a first doping and the plurality of second regions are of a second doping different than the first doping. A gate electrode overlies the well region where the gate electrode is disposed laterally over a portion of the plurality of first regions and a portion of the plurality of second regions.

A method to fabricate a transistor includes implanting dopants into a semiconductor to form a drift layer having majority carriers of a first type; etching a trench into the semiconductor; thermally growing an oxide liner into and on the trench and the drift layer; depositing an oxide onto the oxide liner on the trench to form a shallow trench isolation region; implanting dopants into the semiconductor to form a drain region in contact with the drift layer and having majority carriers of the first type; implanting dopants into the semiconductor to form a body region having majority carriers of a second type; forming a gate oxide over a portion of the drift layer and the body region; forming a gate over the gate oxide; and implanting dopants into the body region to form a source region having majority carriers of the first type.

A semiconductor high-voltage device includes a semiconductor substrate; a high-voltage well in the semiconductor substrate; a drift region in the high-voltage well; a recessed channel region adjacent to the drift region; a heavily doped drain region in the drift region and spaced apart from the recessed channel; an isolation structure between the recessed channel region and the heavily doped drain region in the drift region; a buried gate dielectric layer on the recessed channel region, wherein the top surface of the buried gate dielectric layer is lower than the top surface of the heavily doped drain region; and a gate on the buried gate dielectric layer.

A field-effect transistor for terahertz wave detection using a gate as an antenna includes a silicon substrate including a source and a drain formed outside a channel region surrounding the source, and a gate formed to be spaced apart from the silicon substrate and correspond to the channel region, on a dielectric layer formed on a surface of the silicon substrate, in which the drain has a width determined based on a first performance parameter associated with a terahertz wave reception rate of the field-effect transistor and the channel region has a width determined based on a second performance parameter associated with detection of a terahertz wave to be received by the field-effect transistor.