The present examples relate to a semiconductor chip having a level shifter with an electrostatic discharge (ESD) protection circuit and a device applying to multiple power supply lines with high and low power inputs to protect the level shifter from the static ESD stress. More particularly, the present examples relate to using a feature to protect a semiconductor device in a level shifter from the ESD stress by using ESD stress blocking region adjacent to a gate electrode of the semiconductor device. The ESD stress blocking region increases a gate resistance of the semiconductor device, which results in reducing the ESD stress applied to the semiconductor device itself.

The disclosed subject matter provides an LDMOS device and fabrication method thereof. In an LDMOS device, a drift region and a body region are formed in a substrate. A first trench is formed in the drift region and in the substrate between the drift region and the body region. The first trench is separated from the drift region by a first shallow trench isolation structure. A gate dielectric layer is formed on a side surface and a bottom surface of the first trench. A gate electrode filling up the first trench is formed on the gate dielectric layer with a top surface above a top surface of the semiconductor substrate. A source region is formed in the body region on one side of the gate electrode and a drain region is formed in the drift region on another side of the gate electrode.

A semiconductor device is provided. The device may include a semiconductor layer; and a doped well disposed in the semiconductor layer and having a first conductivity type. The device may also include a drain region, a source region, and a body region, where the source and body regions may operate in different voltages. Further, the device may include a first doped region having a second conductivity type, the first doped region disposed between the source region and the doped well; and a second doped region having the first conductivity type and disposed under the source region. The device may include a third doped region having the second conductivity type and disposed in the doped well; and a fourth doped region disposed above the third doped region, the fourth doped region having the first conductivity type. Additionally, the device may include a gate and a field plate.

An integrated circuit which includes a field-plated FET is formed by forming a first opening in a layer of oxide mask, exposing an area for a drift region. Dopants are implanted into the substrate under the first opening. Subsequently, dielectric sidewalls are formed along a lateral boundary of the first opening. A field relief oxide is formed by thermal oxidation in the area of the first opening exposed by the dielectric sidewalls. The implanted dopants are diffused into the substrate to form the drift region, extending laterally past the layer of field relief oxide. The dielectric sidewalls and layer of oxide mask are removed after the layer of field relief oxide is formed. A gate is formed over a body of the field-plated FET and over the adjacent drift region. A field plate is formed immediately over the field relief oxide adjacent to the gate.

An integrated circuit which includes a field-plated FET is formed by forming a first opening in a layer of oxide mask, exposing an area for a drift region. Dopants are implanted into the substrate under the first opening. Subsequently, dielectric sidewalls are formed along a lateral boundary of the first opening. A field relief oxide is formed by thermal oxidation in the area of the first opening exposed by the dielectric sidewalls. The implanted dopants are diffused into the substrate to form the drift region, extending laterally past the layer of field relief oxide. The dielectric sidewalls and layer of oxide mask are removed after the layer of field relief oxide is formed. A gate is formed over a body of the field-plated FET and over the adjacent drift region. A field plate is formed immediately over the field relief oxide adjacent to the gate.

A lateral double diffused metal oxide semiconductor field-effect transistor includes semiconductor substrates, body regions positioned in the semiconductor substrates, drift regions positioned in the semiconductor substrates, source regions and a body leading-out region which are positioned in the body regions and spaced from the drift regions, a field region and drain regions which are positioned in the drift regions, and gates positioned on the surfaces of the semiconductor substrates to partially cover the body regions, the drift regions and the field region, wherein the field region is of a finger-like structure and comprises a plurality of strip field regions which extend from the source regions to the drain regions and are isolated by the active regions; and the strip field regions provided with strip gate extending regions extending from the gates.

A laterally diffused metal oxide semiconductor (LDMOS) transistor structure with improved unclamped inductive switching immunity. The LDMOS includes a substrate and an adjacent epitaxial layer both of a first conductivity type. A gate structure is above the epitaxial layer. A drain region and a source region, both of a second conductivity type, are within the epitaxial layer. A channel is formed between the source and drain region and arranged below the gate structure. A body structure of the first conductivity type is at least partially formed under the gate structure and extends laterally under the source region, wherein the epitaxial layer is less doped than the body structure. A conductive trench-like feed-through element passes through the epitaxial layer and contacts the substrate and the source region. The LDMOS includes a tub region of the first conductivity type formed under the source region, and adjacent laterally to and in contact with said body structure and said trench-like feed-through element.

A planar gate power MOSFET includes a substrate having a semiconductor surface doped a first conductivity type, a plurality of transistor cells (cells) including a first cell and at least a second cell each having a gate stack over a body region. A trench has an aspect ratio of >3 extending down from a top side of the semiconductor surface between the gate stacks providing a source contact (SCT) from a source doped a second conductivity type to the substrate. A field plate (FP) is over the gate stacks that provides a liner for the trench. The trench has a refractory metal or platinum-group metal (PGM) metal filler within. A drain doped the second conductivity type is in the semiconductor surface on a side of the gate stacks opposite the trench.

A high-voltage FinFET device having LDMOS structure and a method for manufacturing the same are provided. The method includes: providing a substrate with a fin structure to define a first and a second type well regions; forming a trench in the first-type well region to separate the fin structure into a first part and a second part; forming a STI structure in the trench; forming a first and a second polycrystalline silicon gate stack structures at the fin structure; forming discontinuous openings on the exposed fin structure and growing an epitaxial material layer in the openings; doping the epitaxial material layer to form a drain and a source doped layers in the first and second parts respectively; and performing a RMG process to replace the first and second polycrystalline silicon gate stack structures with a first and second metal gate stack structures respectively.

A semiconductor device and methods for forming the same are provided. The semiconductor device includes a first doped region and a second, oppositely doped, region both formed in a substrate, a first gate formed overlying a portion of the first doped region and a portion of the second doped region, two or more second gates formed over the substrate overlying a different portion of the second doped region, one or more third doped regions in the second doped region disposed only between the two or more second gates such that the third doped region and the second doped region having opposite conductivity types, a source region in the first doped region, and a drain region in the second doped region disposed across the second gates from the first gate.