Abstract:
A memory device may include a semiconductor substrate, and a memory transistor in the semiconductor substrate. The memory transistor may include source and drain regions in the semiconductor substrate and a channel region therebetween, and a gate stack having a first dielectric layer over the channel region, a second dielectric layer over the first dielectric layer, a first diffusion barrier layer over the second dielectric layer, a first electrically conductive layer over the first diffusion barrier layer, a second diffusion barrier layer over the first electrically conductive layer, and a second electrically conductive layer over the second diffusion barrier layer. The first and second dielectric layers may include different dielectric materials, and the first diffusion barrier layer may be thinner than the second diffusion barrier layer.
Abstract:
Despite improvements in FinFETs and strained silicon devices, transistors continue to suffer performance degradation as device dimensions shrink. These include, in particular, leakage of charge between the semiconducting channel and the substrate. An isolated channel FinFET device prevents channel-to-substrate leakage by inserting an insulating layer between the channel (fin) and the substrate. The insulating layer isolates the fin from the substrate both physically and electrically. To form the isolated FinFET device, an array of bi-layer fins can be grown epitaxially from the silicon surface, between nitride columns that provide localized insulation between adjacent fins. Then, the lower fin layer can be removed, while leaving the upper fin layer, thus yielding an interdigitated array of nitride columns and semiconducting fins suspended above the silicon surface. A resulting gap underneath the upper fin layer can then be filled in with oxide to isolate the array of fin channels from the substrate.
Abstract:
Despite improvements in FinFETs and strained silicon devices, transistors continue to suffer performance degradation as device dimensions shrink. These include, in particular, leakage of charge between the semiconducting channel and the substrate. An isolated channel FinFET device prevents channel-to-substrate leakage by inserting an insulating layer between the channel (fin) and the substrate. The insulating layer isolates the fin from the substrate both physically and electrically. To form the isolated FinFET device, an array of bi-layer fins can be grown epitaxially from the silicon surface, between nitride columns that provide localized insulation between adjacent fins. Then, the lower fin layer can be removed, while leaving the upper fin layer, thus yielding an interdigitated array of nitride columns and semiconducting fins suspended above the silicon surface. A resulting gap underneath the upper fin layer can then be filled in with oxide to isolate the array of fin channels from the substrate.
Abstract:
Methods and structures for forming strained-channel finFETs are described. Fin structures for finFETs may be formed in two epitaxial layers that are grown over a bulk substrate. A first thin epitaxial layer may be cut and used to impart strain to an adjacent channel region of the finFET via elastic relaxation. The structures exhibit a preferred design range for increasing induced strain and uniformity of the strain over the fin height.
Abstract:
A semiconductor device may include a substrate, a fin above the substrate and having a channel region therein, and source and drain regions adjacent the channel region to generate shear and normal strain on the channel region. A semiconductor device may include a substrate, a fin above the substrate and having a channel region therein, source and drain regions adjacent the channel region, and a gate over the channel region. The fin may be canted with respect to the source and drain regions to generate shear and normal strain on the channel region.
Abstract:
A semiconductor device may include a substrate, a fin above the substrate and having a channel region therein, and source and drain regions adjacent the channel region to generate shear and normal strain on the channel region. A semiconductor device may include a substrate, a fin above the substrate and having a channel region therein, source and drain regions adjacent the channel region, and a gate over the channel region. The fin may be canted with respect to the source and drain regions to generate shear and normal strain on the channel region.
Abstract:
The method of manufacturing a structure comprising one or several strained semiconducting zones capable of forming one or several transistor channel regions, the method including the following steps: a) providing a substrate coated with a masking layer wherein there are one or several first slits exposing one or several first oblong semiconducting portions made of a first semiconducting material and extending in a first direction, b) making a second semiconducting material grow with a mesh parameter different from the mesh parameter of the first semiconducting material, so as to form one or several first semiconducting blocks strained along the first direction, on said one or several first oblong semiconducting portions.
Abstract:
A semiconductor device may include a substrate, a fin above the substrate and having a channel region therein, and source and drain regions adjacent the channel region to generate shear and normal strain on the channel region. A semiconductor device may include a substrate, a fin above the substrate and having a channel region therein, source and drain regions adjacent the channel region, and a gate over the channel region. The fin may be canted with respect to the source and drain regions to generate shear and normal strain on the channel region.
Abstract:
A method of making a semiconductor device includes forming a first spacer for at least one gate stack on a first semiconductor material layer, and forming a respective second spacer for each of source and drain regions adjacent the at least one gate. Each second spacer has a pair of opposing sidewalls and an end wall coupled thereto. The method includes filling the source and drain regions with a second semiconductor material while the first and second spacers provide confinement.
Abstract:
The presence of a facet or a void in an epitaxially grown crystal indicates that crystal growth has been interrupted by defects or by certain material boundaries. Faceting can be suppressed during epitaxial growth of silicon compounds that form source and drain regions of strained silicon transistors. It has been observed that faceting can occur when epitaxial layers of certain silicon compounds are grown adjacent to an oxide boundary, but faceting does not occur when the epitaxial layer is grown adjacent to a silicon boundary or adjacent to a nitride boundary. Because epitaxial growth of silicon compounds is often necessary in the vicinity of isolation trenches that are filled with oxide, techniques for suppression of faceting in these areas are of particular interest. One such technique, presented herein, is to line the isolation trenches with SiN to provide a barrier between the oxide and the region in which epitaxial growth is intended.