A transistor includes a substrate and a gate over the substrate. The transistor further includes a source and a drain over the substrate on opposite sides of the gate. The transistor further includes a channel region beneath the gate separating the source from the drain, the channel region having a channel width with respect to a surface of the substrate greater than a width of the gate with respect to the surface of the substrate. The transistor further includes a silicide over a first portion of the drain, wherein a second portion of the drain, closer to the gate than the first portion, is an unsilicided region.

A FinFET includes a semiconductor fin, and a source region and a drain region in the same semiconductor fin. The drain region has a first fin height above a trench isolation; and the source region has a second fin height above the trench isolation. The first fin height is less than the second fin height. The FinFET may be used, for example, in a scaled laterally diffused metal-oxide semiconductor (LDMOS) application, and exhibits reduced parasitic capacitance for improved radio frequency (RF) performance. A drain extension region may have the first fin height, and a channel region may have the second fin height. A method of making the FinFET is also disclosed.

According to one embodiment, the gate insulating film is provided on a semiconductor region including the body region and the drift region between the source region and the drain region. The gate insulating film includes a first part and a second part. The first part is provided on the source region side. The second part is provided on the drain region side and thicker than the first part. The insulating portion is provided in the semiconductor region under a boundary between the first part and the second part of the gate insulating film.

A semiconductor device includes: a substrate, a gate structure on the substrate, and a spacer adjacent to the gate structure, in which the spacer extends to a top surface of the gate structure, a top surface of the spacer includes a planar surface, the spacer encloses an air gap, and the spacer is composed of a single material. The gate structure includes a high-k dielectric layer, a work function metal layer, and a low resistance metal layer, in which the high-k dielectric layer is U-shaped. The semiconductor device also includes an interlayer dielectric (ILD) layer around the gate structure and a hard mask on the spacer, in which the top surface of the hard mask is even with the top surface of the ILD layer.

A semiconductor device includes etch stop films formed on the first gate electrode, the first source region, the first drain region, and the shallow trench isolation regions, respectively. First interlayer insulating films are formed on the etch stop film, respectively. Deep trenches are formed in the substrate between adjacent ones of the first interlayer insulating films to overlap the shallow trench isolation regions. Sidewall insulating films are formed in the deep trenches, respectively. A gap-fill insulating film is formed on the sidewall insulating film. A second interlayer insulating film is formed on the gap-fill insulating film. A top surface of the second interlayer insulating film is substantially planar and a bottom surface of the second interlayer insulating film is undulating.

A method includes forming a gate spacer along sidewalls of a gate structure, forming a source region and a drain region on opposite sides of the gate structure, wherein a sidewall of the source region is vertically aligned with a first sidewall of the gate spacer, depositing a dielectric layer over the substrate, depositing a conductive layer over the dielectric layer, patterning the dielectric layer and the conductive layer to form a field plate, wherein the dielectric layer comprises a horizontal portion extending from the second drain/source region to a second sidewall of the gate spacer and a vertical portion formed along the second sidewall of the gate spacer, forming a plurality of metal silicide layers by applying a salicide process to the conductive layer, the gate structure, the first drain/source region and the second drain/source region and forming contact plugs over the plurality of metal silicide layers.

An electronic device can include a transistor having a drain region, a source region, a dielectric layer, and a gate electrode. The dielectric layer can have a first portion and a second portion, wherein the first portion is relatively thicker and closer to the drain region; the second portion is relatively thinner and closer to the source region. The gate electrode of the transistor can overlie the first and second portions of the dielectric layer. In another aspect, an electronic device can be formed using two different dielectric layers having different thicknesses. A gate electrode within the electronic device can be formed over portions of the two different dielectric layers. The process can eliminate masking and doping steps that may be otherwise used to keep the drain dopant concentration closer to the concentration as originally formed.

A semiconductor device including a substrate having a drain region therein is provided. A gate-electrode layer is disposed on the drain region. A first field-plate conductor is disposed on the substrate and overlaps the drain region. A gap is located laterally between the first field-plate conductor and the gate-electrode layer. A second field-plate conductor covers the first field-plate conductor and the gap. The second field-plate conductor is separated from the first field-plate conductor. A method for forming the semiconductor device is also provided.

Devices, structures, and methods thereof for providing a Schottky or Schottky-like contact as a source region and/or a drain region of a power transistor are disclosed. A power transistor structure comprises a substrate of a first dopant polarity, a drift region formed on or within the substrate, a body region formed on or within the drift region, a gate structure formed on or within the substrate, a source region adjacent to the gate structure, a drain region formed adjacent to the gate structure. At least one of the source region and the drain region is formed from a Schottky or Schottky-like contact substantially near a surface of the substrate, comprising a silicide layer and an interfacial dopant segregation layer. The Schottky or Schottky-like contact is formed by low-temperature annealing a dopant segregation implant in the source and/or drain region.

Disclosed are methods that employ a mask with openings arranged in a pattern of elongated trenches and holes of varying widths to achieve a linearly graded conductivity level. These methods can be used to form a lateral double-diffused metal oxide semiconductor field effect transistor (LDMOSFET) with a drain drift region having an appropriate type conductivity at a level that increases essentially linearly from the body region to the drain region. Furthermore, these methods also provide for improve manufacturability in that multiple instances of this same pattern can be used during a single dopant implant process to implant a first dopant with a first type (e.g., N-type) conductivity into the drain drift regions of both first and second type LDMOSFETs (e.g., N and P-type LDMOSFETs, respectively). In this case, the drain drift region of a second type LDMOSFET can subsequently be uniformly counter-doped. Also disclosed are the resulting semiconductor structures.