A structure includes a laterally diffused (LD) MOSFET with an n-type drift region disposed on a surface of a substrate and a p-type body region contained in the drift region. The structure further includes an n-type source region contained in the p-type body region; an n-type drain region contained in the n-type drift region; a gate electrode disposed on a gate dielectric overlying a portion of the p-type body region and the n-type drift region and an electrically conductive field shield member disposed within the n-type drift region at least partially beneath the p-type body region and generally parallel to the gate electrode. The electrically conductive buried field shield member is contained within and surrounded by a layer of buried field shield oxide and is common to both a first LD MOSFET and a second LD MOSFET that are connected in parallel. Methods to fabricate the structure are also disclosed.

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 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 semiconductor substrate, a gate oxide layer, and a polysilicon field plate. The semiconductor substrate includes a drift region and a well region. An end of the drift region is arranged with a drain region, and an end of the well region is arranged with a source region. The gate oxide layer is arranged on the semiconductor substrate and disposed between the source region and the drain region. The polysilicon field plate is arranged on the gate oxide layer. At least a portion of the polysilicon field plate is projected onto the drift region and includes at least two field-plate regions. While the semiconductor device is operating, in a direction from an end of the drift region near the well region approaching the drain region, an equivalent electrical thickness of an insulating layer between the polysilicon field plate and the drift region gradually increases.

A lateral diffusion metal oxide semiconductor (LDMOS) device includes a first fin-shaped structure on a substrate, a shallow trench isolation (STI) adjacent to the first fin-shaped structure, a first gate structure on the first fin-shaped structure, a spacer adjacent to the first gate structure, and a contact field plate adjacent to the first gate structure and directly on the STI. Preferably, a sidewall of the spacer is aligned with a sidewall of the first fin-shaped structure.

An IC structure that includes a trench isolation (TI) in a substrate having three portions of different dielectric materials. The portions may also have different widths. The TI may include a lower portion including a first dielectric material and having a first width, a middle portion including the first dielectric material and an outer second dielectric material, and an upper portion including a third dielectric material and having a second width greater than the first width. The first, second and third dielectric materials are different.

A semiconductor substrate is provided. A trench isolation region is formed in the semiconductor substrate. A resist pattern having an opening exposing the trench isolation region and partially exposing the semiconductor substrate is disposed adjacent to the trench isolation region. A first ion implantation process is performed to implant first dopants into the semiconductor substrate through the opening, thereby forming a well region in the semiconductor substrate. The trench isolation region is within the well region. A second ion implantation process is performed to implant second dopants into the semiconductor substrate through the opening, thereby forming an extended doped region contiguous with the well region. The resist pattern is then removed. After removing the resist pattern, a gate dielectric layer is formed on the semiconductor substrate. A gate is then formed on the gate dielectric layer. The gate overlaps with the extended doped region.

The source region, drain region, buried insulating film, gate insulating film, and gate electrode of the semiconductor device are formed in a main surface of a semiconductor substrate. The buried insulating film is buried in a first trench formed between the source and drain regions. The first trench has a first side surface and a first bottom surface. The first side surface faces the source region in a first direction extending from one of the source and drain regions to the other. The first bottom surface is connected to the first side surface and is along the main surface of the semiconductor substrate. A crystal plane of a first surface of the semiconductor substrate, which is the first side surface of the first trench, is (111) plane. A crystal plane of a second surface of the semiconductor substrate, which is the bottom surface of the first trench, is (100) plane.

The present disclosure introduces a microelectronic device including a source side field plate in a microelectronic device. The microelectronic device may be configured as a metal oxide semiconductor (MOS) transistor, a laterally diffused metal oxide semiconductor (LDMOS) transistor, a drain extended metal oxide semiconductor (DEMOS) transistor, a bipolar junction transistor, a junction field effect transistor, a CMOS transistor, or a gated bipolar device. The source side field plate extends over the source region by a distance which is more than a quarter of the width of the source region. Transistors may suffer from Vt shifts during gate and drain stress over time. The source side field plate reduces the electric field of the transistor near the gate electrode corner on the source side of the transistor. The gate injection current on the source side and electron trapping in the gate oxide thereby reduced which reduces Vt shifts over time.

In some embodiments, the present disclosure relates to an integrated chip that includes a source region and a drain region arranged over and/or within a substrate. Further, a shallow trench isolation (STI) structure is arranged within the substrate and between the source and drain regions. A gate electrode is arranged over the substrate, over the STI structure, and between the source and drain regions. A portion of the gate electrode extends into the STI structure such that a bottommost surface of the portion of the gate electrode is arranged between a topmost surface of the STI structure and a bottommost surface of the STI structure.