A semiconductor device 1 includes a base body 3 that includes a p type substrate 4 and an n type semiconductor layer 5 formed on the p type substrate 4 and includes an element region 2 having a transistor 40 with the n type semiconductor layer as a drain, a p type element isolation region 7 that is formed in a surface layer portion of the base body such as to demarcate the element region, and a conductive wiring 25 that is disposed on a peripheral edge portion of the element region and is electrically connected to the n type semiconductor layer. The transistor includes an n.sup.+ type drain contact region 14 that is formed in a surface layer portion of the n type semiconductor layer in the peripheral edge portion of the element region. The conductive wiring is disposed such as to cover at least a portion of an element termination region 30 between the n.sup.+ type drain contact region and the p type element isolation region.

A semiconductor device includes a semiconductor film and a gate structure on the semiconductor film. The gate structure includes a multi-stepped gate dielectric on the semiconductor film and a gate electrode on the multi-stepped gate dielectric. The multi-stepped gate dielectric includes a first gate dielectric segment having a first thickness and a second gate dielectric segment having a second thickness that is less than the first thickness.

A semiconductor device can include: a substrate having a first doping type; a first well region located in the substrate and having a second doping type, where the first well region is located at opposite sides of a first region of the substrate; a source region and a drain region located in the first region, where the source region has the second doping type, and the drain region has the second doping type; and a buried layer having the second doping type located in the substrate and below the first region, where the buried layer is incontact with the first well region, where the first region is surrounded by the buried layer and the first well region, and the first doping type is opposite to the second doping type.

An integrated circuit has a P-type substrate and an N-type LDMOS transistor. The LDMOS transistor includes a boron-doped diffused well (DWELL-B) and an arsenic-doped diffused well (DWELL-As) located within the DWELL-B. A first polysilicon gate having first sidewall spacers and a second polysilicon gate having second sidewall spacers are located over opposite edges of the DWELL-B. A source/IBG region includes a first source region adjacent the first polysilicon gate, a second source region adjacent the second polysilicon gate, and an integrated back-gate (IBG) region located between the first and second source regions. The first source region and the second source region each include a lighter-doped source sub-region, the IBG region including an IBG sub-region having P-type dopants, and the source/IBG region includes a heavier-doped source sub-region.

Exemplary power semiconductor devices with features providing increased breakdown voltage and other benefits are disclosed.

A semiconductor device includes a first transistor, a second transistor, and a third transistor. The first transistor includes a first gate insulator, a first source region and a first drain region, a pair of lightly doped drain (LDD) regions that are each shallower than the first source region and the first drain region, and a first gate electrode. The second transistor includes a second gate insulator, a second source region and a second drain region, a pair of drift regions that encompass the second source region and the second drain region respectively, and a second gate electrode, and the third transistor comprises a third gate insulator, a third source region and a third drain region, and a pair of drift regions that encompass the third source and the third drain regions respectively, and a third gate electrode. The second gate insulator is thinner than the other gate insulators.

A laterally diffused metal oxide semiconductor device can include: a base layer; a source region and a drain region located in the base layer; a first dielectric layer located on a top surface of the base layer and adjacent to the source region; a voltage withstanding layer located on the top surface of the base layer and located between the first dielectric layer and the drain region; a first conductor at least partially located on the first dielectric layer; a second conductor at least partially located on the voltage withstanding layer; and a source electrode electrically connected to the source region, where the first and second conductors are spatially isolated, and the source electrode at least covers a space between the first and second conductors.

A mask layout for forming a semiconductor device includes an active mask pattern, a gate electrode mask pattern, a silicide blocking mask pattern, and a contact mask pattern. The active mask pattern forms source and drain regions in a substrate. The gate electrode mask pattern, disposed to overlap the active mask pattern, forms a gate electrode between the source region and the drain region. The silicide blocking mask pattern is disposed to overlap the gate electrode mask pattern and the active mask pattern in the gate electrode, the source region, and the drain regions to form a silicide blocking region. The contact mask pattern, disposed spaced apart from the silicide blocking mask pattern, forms a contact plug on the substrate. The silicide blocking mask pattern covers the gate electrode mask pattern and extends to the active mask pattern.

A capacitor is provided for integration with a MOSFET device(s) formed on the same substrate. The capacitor comprises a first plate including a doped semiconductor layer of a first conductivity type, an insulating layer formed on an upper surface of the doped semiconductor layer, and a second plate including a polysilicon layer formed on an upper surface of the insulating layer. An inversion layer is formed in the doped semiconductor layer, beneath the insulating layer and proximate the upper surface of the doped semiconductor layer, as a function of an applied voltage between the first and second plates of the capacitor. At least one doped region of a second conductivity type, opposite the first conductivity type, is formed in the doped semiconductor layer adjacent to a drain and/or source region of the first conductivity type formed in the MOSFET device. The doped region is electrically connected to the inversion layer.

A semiconductor device includes a source region, a drain region, and a gate insulating film formed on a substrate, a gate electrode formed on the gate insulating film, a first insulating film pattern formed to extend from the source region to a part of a top surface of the gate electrode, and a spacer formed on a side surface of the gate electrode in a direction of the drain region.