Abstract:
Methods and structures for forming a localized, strained region of a substrate are described. Trenches may be formed at boundaries of a localized region of a substrate. An upper portion of sidewalls at the localized region may be covered with a covering layer, and a lower portion of the sidewalls at the localized region may not be covered. A converting material may be formed in contact with the lower portion of the localized region, and the substrate heated. The heating may introduce a chemical species from the converting material into the lower portion, which creates stress in the localized region. The methods may be used to form strained-channel finFETs.
Abstract:
A static induction transistor is formed on a silicon carbide substrate doped with a first conductivity type. First recessed regions in a top surface of the silicon carbide substrate are filled with epitaxially grown gate regions in situ doped with a second conductivity type. Epitaxially grown channel regions in situ doped with the first conductivity type are positioned between adjacent epitaxial gate regions. Epitaxially grown source regions in situ doped with the first conductivity type are positioned on the epitaxial channel regions. The bottom surface of the silicon carbide substrate includes second recessed regions vertically aligned with the channel regions and silicided to support formation of the drain contact. The top surfaces of the source regions are silicided to support formation of the source contact. A gate lead is epitaxially grown and electrically coupled to the gate regions, with the gate lead silicided to support formation of the gate contact.
Abstract:
Methods and structures for forming strained-channel FETs are described. A strain-inducing layer may be formed under stress in a silicon-on-insulator substrate below the insulator. Stress-relief cuts may be formed in the strain-inducing layer to relieve stress in the strain-inducing layer. The relief of stress can impart strain to an adjacent semiconductor layer. Strained-channel, fully-depleted SOI FETs and strained-channel finFETs may be formed from the adjacent semiconductor layer. The amount and type of strain may be controlled by etch depths and geometries of the stress-relief cuts and choice of materials for the strain-inducing layer.
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:
Methods and structures for increasing strain in fully insulated finFETs are described. The finFET structures may be formed on an insulating layer and include source, channel, and drain regions that are insulated all around. During fabrication, the source and drain regions may be formed as suspended structures. A strain-inducing material may be formed around the source and drain regions on four contiguous sides so as to impart strain to the channel region of the finFET.
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:
The invention concerns a method of forming a semiconductor layer having uniaxial stress including: forming, in a semiconductor structure having a stressed semiconductor layer, one or more first isolation trenches in a first direction for delimiting a first dimension of at least one transistor to be formed in said semiconductor structure; forming, in the semiconductor structure, one or more second isolation trenches in a second direction for delimiting a second dimension of the at least one transistor, the first and second isolation trenches being at least partially filled with an insulating material; and before or after the formation of the second isolation trenches, decreasing the viscosity of the insulating material in the first isolation trenches by implanting atoms of a first material into the first isolation trenches, wherein atoms of the first material are not implanted into the second isolation trenches.
Abstract:
The disclosure concerns a method of stressing a semiconductor layer comprising: forming, over a silicon on insulator structure having a semiconductor layer in contact with an insulating layer, one or more stressor blocks aligned with first regions of said semiconductor layer in which transistor channels are to be formed, wherein said stressor blocks are stressed such that they locally stress said semiconductor layer; and deforming second regions of said insulating layer adjacent to said first regions by temporally decreasing, by annealing, the viscosity of said insulator layer.
Abstract:
A thermal annealing flow process includes the steps of: depositing a metal or metal alloy on a silicon semiconductor structure, performing a first annealing of a rapid thermal anneal (RTA) type to produce a metal rich phase in a portion of the silicon semiconductor structure, removing unreacted metal or metal alloy and performing a second annealing as a millisecond annealing at a temperature that is below a melt temperature of the silicon material present in the silicon semiconductor structure.
Abstract:
Integrated circuits are disclosed in which the strain properties of adjacent pFETs and nFETs are independently adjustable. The pFETs include compressive-strained SiGe on a silicon substrate, while the nFETs include tensile-strained silicon on a strain-relaxed SiGe substrate. Adjacent n-type and p-type FinFETs are separated by electrically insulating regions formed by a damascene process. During formation of the insulating regions, the SiGe substrate supporting the n-type devices is permitted to relax elastically, thereby limiting defect formation in the crystal lattice of the SiGe substrate.