Abstract:
An integrated transistor in the form of a nanoscale electromechanical switch eliminates CMOS current leakage and increases switching speed. The nanoscale electromechanical switch features a semiconducting cantilever that extends from a portion of the substrate into a cavity. The cantilever flexes in response to a voltage applied to the transistor gate thus forming a conducting channel underneath the gate. When the device is off, the cantilever returns to its resting position. Such motion of the cantilever breaks the circuit, restoring a void underneath the gate that blocks current flow, thus solving the problem of leakage. Fabrication of the nano-electromechanical switch is compatible with existing CMOS transistor fabrication processes. By doping the cantilever and using a back bias and a metallic cantilever tip, sensitivity of the switch can be further improved. A footprint of the nano-electromechanical switch can be as small as 0.1×0.1 μm2.
Abstract:
A dual width SOI FinFET is disclosed in which different portions of a strained fin have different widths. A method of fabrication of such a dual width FinFET entails laterally recessing the strained fin in the source and drain regions using a wet chemical etching process so as to maintain a high degree of strain in the fin while trimming the widths of fin portions in the source and drain regions to less than 5 nm. The resulting FinFET features a wide portion of the fin in the channel region underneath the gate, and a narrower portion of the fin in the source and drain regions. An advantage of the narrower fin is that it can be more easily doped during the growth of the epitaxial raised source and drain regions.
Abstract:
A vertical junction field effect transistor (JFET) is supported by a semiconductor substrate that includes a source region within the semiconductor substrate doped with a first conductivity-type dopant. A fin of semiconductor material doped with the first conductivity-type dopant has a first end in contact with the source region and further includes a second end and sidewalls between the first and second ends. A drain region is formed of first epitaxial material grown from the second end of the fin and doped with the first conductivity-type dopant. A gate structure is formed of second epitaxial material grown from the sidewalls of the fin and doped with a second conductivity-type dopant.
Abstract:
A method for making a semiconductor device may include forming a dummy gate above a semiconductor layer on an insulating layer, forming sidewall spacers above the semiconductor layer and on opposing sides of the dummy gate, forming source and drain regions on opposing sides of the sidewall spacers, and removing the dummy gate and underlying portions of the semiconductor layer between the sidewall spacers to provide a thinned channel region having a thickness less than a remainder of the semiconductor layer outside the thinned channel region. The method may further include forming a replacement gate stack over the thinned channel region and between the sidewall spacers and having a lower portion extending below a level of adjacent bottom portions of the sidewall spacers.
Abstract:
An integrated circuit includes a substrate supporting a transistor having a source region and a drain region. A high dopant concentration delta-doped layer is present on the source region and drain region of the transistor. A set of contacts extend through a pre-metal dielectric layer covering the transistor. A silicide region is provided at a bottom of the set of contacts. The silicide region is formed by a salicidation reaction between a metal present at the bottom of the contact and the high dopant concentration delta-doped layer on the source region and drain region of the transistor.
Abstract:
A SOI substrate layer formed of a silicon semiconductor material includes adjacent first and second regions. A portion of the silicon substrate layer in the second region is removed such that the second region retains a bottom portion made of the silicon semiconductor material. An epitaxial growth of a silicon-germanium semiconductor material is made on the bottom portion to produce a silicon-germanium region. The silicon region is patterned to define a first fin structure of a FinFET of a first (for example, n-channel) conductivity type. The silicon-germanium region is also patterned to define a second fin structure of a FinFET of a second (for example, p-channel) conductivity type.
Abstract:
A method for making a semiconductor device may include forming, on a first semiconductor layer of a semiconductor-on-insulator (SOI) wafer, a second semiconductor layer comprising a second semiconductor material different than a first semiconductor material of the first semiconductor layer. The method may further include performing a thermal treatment in a non-oxidizing atmosphere to diffuse the second semiconductor material into the first semiconductor layer, and removing the second semiconductor layer.
Abstract:
An SOI substrate includes first and second active regions separated by STI structures and including gate stacks. A spacer layer conformally deposited over the first and second regions including the gate stacks is directionally etched to define sidewall spacers along the sides of the gate stacks. An oxide layer and nitride layer are then deposited. Using a mask, the nitride layer over the first active region is removed, and the mask and oxide layer are removed to expose the SOI substrate in the first active region. Raised source-drain structures are then epitaxially grown adjacent the gate stacks in the first active region and a protective nitride layer is deposited. The masking, nitride layer removal, and oxide layer removal steps are then repeated to expose the SOI in the second active region. Raised source-drain structures are then epitaxially grown adjacent the gate stacks in the second active region.
Abstract:
On a first semiconductor material substrate, an overlying sacrificial layer formed of a second semiconductor material is deposited. In a first region, a first semiconductor material region is formed over the sacrificial layer. In a second region, a second semiconductor material region is formed over the sacrificial layer. The first semiconductor material region is patterned to define a first FinFET fin. The second semiconductor material region is patterned to define a second FinFET fin. The fins are each covered with a cap and sidewall spacer. The sacrificial layer formed of the second semiconductor material is then selectively removed to form an opening below each of the first and second FinFET fins (with those fins being supported by the sidewall spacers). The openings below each of the fins are then filled with a dielectric material that serves to isolate the semiconductive materials of the fins from the substrate.
Abstract:
A method for co-integrating finFETs of two semiconductor material types, e.g., Si and SiGe, on a bulk substrate is described. Fins for finFETs may be formed in an epitaxial layer of a first semiconductor type, and covered with an insulator. A portion of the fins may be removed to form voids in the insulator, and the voids may be filled by epitaxially growing a semiconductor material of a second type in the voids. The co-integrated finFETs may be formed at a same device level.