Abstract:
A modified silicon substrate having a substantially defect-free strain relaxed buffer layer of SiGe is suitable for use as a foundation on which to construct a high performance CMOS FinFET device. The substantially defect-free SiGe strain-relaxed buffer layer can be formed by making cuts in, or segmenting, a strained epitaxial film, causing edges of the film segments to experience an elastic strain relaxation. When the segments are small enough, the overall film is relaxed so that the film is substantially without dislocation defects. Once the substantially defect-free strain-relaxed buffer layer is formed, strained channel layers can be grown epitaxially from the relaxed SRB layer. The strained channel layers are then patterned to create fins for a FinFET device. In one embodiment, dual strained channel layers are formed—a tensilely strained layer for NFET devices, and a compressively strained layer for PFET devices.
Abstract:
One method disclosed includes, among other things, forming a fin structure comprised of a semiconductor material, a first epi semiconductor material and a second epi semiconductor material, forming a sacrificial gate structure above the fin structure, forming a sidewall spacer adjacent the sacrificial gate structure, performing at least one etching process to remove the portions of the fin structure positioned laterally outside of the sidewall spacer so as to thereby define a fin cavity in the source/drain regions of the device and to expose edges of the fin structure positioned under the sidewall spacer, and performing an epitaxial deposition process to form an epi etch stop layer on the exposed edges of the fin structure positioned under the sidewall spacer and within the fin cavity.
Abstract:
One method disclosed includes, among other things, forming a fin structure comprised of a semiconductor material, a first epi semiconductor material and a second epi semiconductor material, forming a sacrificial gate structure above the fin structure, forming a sidewall spacer adjacent the sacrificial gate structure, performing at least one etching process to remove the portions of the fin structure positioned laterally outside of the sidewall spacer so as to thereby define a fin cavity in the source/drain regions of the device and to expose edges of the fin structure positioned under the sidewall spacer, and performing an epitaxial deposition process to form an epi etch stop layer on the exposed edges of the fin structure positioned under the sidewall spacer and within the fin cavity.
Abstract:
A method for semiconductor fabrication includes providing channel regions on a substrate including at least one Silicon Germanium (SiGe) channel region, the substrate including a plurality of regions including a first region and a second region. Gate structures are formed for a first n-type field effect transistor (NFET) and a first p-type field effect transistor (PFET) in the first region and a second NFET and a second PFET in the second region, the gate structure for the first PFET being formed on the SiGe channel region. The gate structure for the first NFET includes a gate material having a first work function and the gate structures for the first PFET, second NFET and second PFET include a gate material having a second work function such that multi-threshold voltage devices are provided.
Abstract:
Methods and semiconductor structures formed from the methods are provided which facilitate fabricating semiconductor fin structures. The methods include, for example: providing a wafer with at least one semiconductor fin extending above a substrate; transforming a portion of the semiconductor fin(s) into an isolation layer, the isolation layer separating a semiconductor layer of the semiconductor fin(s) from the substrate; and proceeding with forming a fin device(s) of a first architectural type in a first fin region of the semiconductor fin(s), and a fin device(s) of a second architectural type in a second fin region of the semiconductor fin(s), where the first architectural type and the second architectural type are different fin device architectures.
Abstract:
Methods and structures for forming fully insulated finFETs beginning with a bulk semiconductor substrate are described. Fin structures for finFETs may be formed in two epitaxial layers that are grown over a bulk substrate. A first epitaxial layer may be sacrificial. A final gate structure may be formed around the fin structures, and the first epitaxial layer removed to form a void between a fin and the substrate. The void may be filled with an insulator to fully insulate the fin.
Abstract:
Methods and semiconductor structures formed from the methods are provided which facilitate fabricating semiconductor fin structures. The methods include, for example: providing a wafer with at least one semiconductor fin extending above a substrate; transforming a portion of the semiconductor fin(s) into an isolation layer, the isolation layer separating a semiconductor layer of the semiconductor fin(s) from the substrate; and proceeding with forming a fin device(s) of a first architectural type in a first fin region of the semiconductor fin(s), and a fin device(s) of a second architectural type in a second fin region of the semiconductor fin(s), where the first architectural type and the second architectural type are different fin device architectures.
Abstract:
A FinFET device includes a fin structure positioned in the channel region of the device and a gate structure positioned above the fin structure, wherein the fin structure includes a portion of a semiconductor substrate and an epi semiconductor material positioned vertically above the portion of the semiconductor substrate. Sidewall spacers are positioned adjacent the gate structure and a fin cavity is positioned in source/drain regions of the device, wherein the fin structure has edges in a gate width direction that are substantially self-aligned with the sidewall spacers and the semiconductor substrate defines the bottom of the fin cavity. A silicon etch stop layer is positioned on and in contact with the edges of the fin structure and within the fin cavity, and a stressed semiconductor material is positioned on and in contact with the silicon etch stop layer and at least partially within the fin cavity.
Abstract:
A fin structure is formed in and above a substrate and includes a portion of a substrate semiconductor material, a first epi semiconductor material formed above the substrate semiconductor material portion, and a second epi semiconductor material formed above the first epi semiconductor material. A sacrificial gate structure is formed above the fin structure, a sidewall spacer is formed adjacent the sacrificial gate structure, and at least one etching process is performed to remove portions of the fin structure positioned laterally outside of the sidewall spacer so as to define a fin cavity source/drain regions and to expose edges of the fin structure positioned under the spacer. An epi etch stop layer is formed on the exposed edges of the fin structure and within the fin cavity, and the first epi semiconductor material is removed selectively from the fin structure so as to form a channel cavity therein.
Abstract:
Methods and structures for forming fully insulated finFETs beginning with a bulk semiconductor substrate are described. Fin structures for finFETs may be formed in two epitaxial layers that are grown over a bulk substrate. A first epitaxial layer may be sacrificial. A final gate structure may be formed around the fin structures, and the first epitaxial layer removed to form a void between a fin and the substrate. The void may be filled with an insulator to fully insulate the fin.