Abstract: Techniques are disclosed for forming group III-V material transistors employing nitride-based dopant diffusion barrier layers. The techniques can include growing the dilute nitride-based barrier layer as a relatively thin layer of III-V material in the sub-channel (or sub-fin) region of a transistor, near the substrate/III-V material interface, for example. Such a nitride-based barrier layer can be used to trap atoms from the substrate at vacancy sites within the III-V material. Therefore, the barrier layer can arrest substrate atoms from diffusing in an undesired manner by protecting the sub-channel layer from being unintentionally doped due to subsequent processing in the transistor fabrication. In addition, by forming the barrier layer pseudomorphically, the lattice mismatch of the barrier layer with the sub-channel layer in the heterojunction stack becomes insignificant. In some embodiments, the group III-V alloyed with nitrogen (N) material may include an N concentration of less than 5, 2, or 1.

Abstract: Techniques are disclosed for forming diverse transistor channel materials enabled by a thin, inverse-graded, germanium (Ge)-based layer. The thin, inverse-graded, Ge-based layer (e.g., having a thickness of at most 500 nm) can then serve as a template for the growth of compressively strained PMOS channel material and tensile strained NMOS channel material to achieve gains in hole and electron mobility, respectively, in the channel regions of the devices. Such a relatively thin Ge-based layer can be formed with suitable surface quality/relaxation levels due to the inverse grading of the Ge concentration in the layer, where the Ge concentration is relatively greatest near the substrate and relatively lowest near the overlying channel material layer. In addition to the inverse-graded Ge concentration, the Ge-based layer may be characterized by the nucleation, and predominant containment, of defects at/near the interface between the substrate and the Ge-based layer.

Abstract: Integrated circuits include fins including an upper/channel region and a lower/sub-channel region, the lower region having a first chemical composition and opposing sidewalls adjacent to an insulator material, and the upper region having a second chemical composition. A first width indicates the distance between the opposing sidewalls of the lower region at a first location is at least 1 nm wider than a second width indicating the distance between the opposing sidewalls of the upper region at a second location, the first location being within 10 nm of the second location (or otherwise relatively close to one another). The first chemical composition is distinct from the second chemical composition and includes a surface chemical composition at an outer surface of the opposing sidewalls of the lower region and a bulk chemical composition therebetween, the surface chemical composition including one or more of oxygen, nitrogen, carbon, chlorine, fluorine, and sulfur.

Abstract: Techniques are disclosed for controlling transistor sub-fin leakage. The techniques can be used for highly scaled finFETs, as well as other non-planar transistors. In some cases, the techniques include exposing a middle portion of a fin structure formed on a substrate and then converting the exposed portion to an electrically isolating material via a doping or oxidation process. For example, a monolayer doping (MLD) process may be used to deliver dopants to the exposed portion of the fin in a self-saturated monolayer scheme. In another example case, thermal oxidation may be used to convert the exposed portion to an insulator material. In some cases, a barrier layer (e.g., including carbon doping) may be located above the exposed portion of the fin to help prevent the doping or oxidation process from affecting the upper region of the fin, which is used for the transistor channel.

Abstract: Techniques are disclosed for forming transistor devices having reduced parasitic contact resistance relative to conventional devices. The techniques can be implemented, for example, using a standard contact stack such as a series of metals on, for example, silicon or silicon germanium (SiGe) source/drain regions. In accordance with one example such embodiment, an intermediate boron doped germanium layer is provided between the source/drain and contact metals to significantly reduce contact resistance. Numerous transistor configurations and suitable fabrication processes will be apparent in light of this disclosure, including both planar and non-planar transistor structures (e.g., FinFETs), as well as strained and unstrained channel structures. Graded buffering can be used to reduce misfit dislocation. The techniques are particularly well-suited for implementing p-type devices, but can be used for n-type devices if so desired.

Abstract: Techniques are disclosed for incorporating high mobility strained channels into fin-based NMOS transistors (e.g., FinFETs such as double-gate, trigate, etc), wherein a stress material is cladded onto the channel area of the fin. In one example embodiment, a germanium or silicon germanium film is cladded onto silicon fins in order to provide a desired tensile strain in the core of the fin, although other fin and cladding materials can be used. The techniques are compatible with typical process flows, and cladding deposition can occur at a plurality of locations within typical process flow. In various embodiments, fins may be formed with a minimum width (or later thinned) so as to improve transistor performance. In some embodiments, a thinned fin also increases tensile strain across the core of a cladded fin. In some cases, strain in the core may be further enhanced by adding an embedded silicon epitaxial source and drain.

Abstract: Techniques are disclosed for incorporating high mobility strained channels into fin-based NMOS transistors (e.g., FinFETs such as double-gate, trigate, etc), wherein a stress material is cladded onto the channel area of the fin. In one example embodiment, a germanium or silicon germanium film is cladded onto silicon fins in order to provide a desired tensile strain in the core of the fin, although other fin and cladding materials can be used. The techniques are compatible with typical process flows, and cladding deposition can occur at a plurality of locations within typical process flow. In various embodiments, fins may be formed with a minimum width (or later thinned) so as to improve transistor performance. In some embodiments, a thinned fin also increases tensile strain across the core of a cladded fin. In some cases, strain in the core may be further enhanced by adding an embedded silicon epitaxial source and drain.

Abstract: Integrated circuit transistor structures are disclosed that reduce n-type dopant diffusion, such as phosphorous or arsenic, from the source region and the drain region of a germanium n-MOS device into adjacent shallow trench isolation (STI) regions during fabrication. The n-MOS transistor device may include at least 75% germanium by atomic percentage. In an example embodiment, the STI is doped with an n-type impurity, in regions of the STI adjacent to the source and/or drain regions, to provide dopant diffusion reduction. In some embodiments, the STI region is doped with an n-type impurity including Phosphorous in a concentration between 1 and 10% by atomic percentage. In some embodiments, the thickness of the doped STI region may range between 10 and 100 nanometers.

Abstract: Gate-all-around integrated circuit structures having nanowires with tight vertical spacing, and methods of fabricating gate-all-around integrated circuit structures having nanowires with tight vertical spacing, are described. For example, an integrated circuit structure includes a vertical arrangement of horizontal silicon nanowires. A vertical spacing between vertically adjacent silicon nanowires is less than 6 nanometers. A gate stack is around the vertical arrangement of horizontal silicon nanowires. A first source or drain structure is at a first end of the vertical arrangement of horizontal silicon nanowires, and a second epitaxial source or drain structure is at a second end of the vertical arrangement of horizontal silicon nanowires.

Abstract: An integrated circuit device with a substrate and a plurality of fins is provided where the fin width is less than 11 nanometers, the fin height is greater than 155 nanometers and the spacing between any two neighboring fins is less than 30 nanometers and each of the fins is in a non-collapsed state. An integrated circuit device with a substrate and a plurality of fins is also provided where the fin width is less than 15 nanometers, the fin height is greater than 190 nanometers and the spacing between any two neighboring fins is less than 30 nanometers and each of the fins is in a non-collapsed state. A method for forming a fin-based transistor structure is also provided where a plurality of fins on a substrate are pre-treated with at least one of a self-assembled monolayer, a non-polar solvent, and a surfactant. One or more of these treatments is provided to reduce the adhesion and/or cohesive forces to prevent the occurrence of fin collapse.

Abstract: Techniques are disclosed for forming high mobility NMOS fin-based transistors having an indium-rich channel region electrically isolated from the sub-fin by an aluminum-containing layer. The aluminum aluminum-containing layer may be provisioned within an indium-containing layer that includes the indium-rich channel region, or may be provisioned between the indium-containing layer and the sub-fin. The indium concentration of the indium-containing layer may be graded from an indium-poor concentration near the aluminum-containing barrier layer to an indium-rich concentration at the indium-rich channel layer. The indium-rich channel layer is at or otherwise proximate to the top of the fin, according to some example embodiments. The grading can be intentional and/or due to the effect of reorganization of atoms at the interface of indium-rich channel layer and the aluminum-containing barrier layer. Numerous variations and embodiments will be appreciated in light of this disclosure.

Abstract: Techniques are disclosed for forming column IV transistor devices having source/drain regions with high concentrations of germanium, and exhibiting reduced parasitic resistance relative to conventional devices. In some example embodiments, the source/drain regions each includes a thin p-type silicon or germanium or SiGe deposition with the remainder of the source/drain material deposition being p-type germanium or a germanium alloy (e.g., germanium:tin or other suitable strain inducer, and having a germanium content of at least 80 atomic % and 20 atomic % or less other components). In some cases, evidence of strain relaxation may be observed in the germanium rich cap layer, including misfit dislocations and/or threading dislocations and/or twins. Numerous transistor configurations can be used, including both planar and non-planar transistor structures (e.g., FinFETs and nanowire transistors), as well as strained and unstrained channel structures.

Abstract: Techniques are disclosed for using compositionally different contact materials for p-type and n-type source/drain regions on a common substrate. The different contact materials may be within a common source/drain contact trench, or in type-dedicated trenches. A given contact trench may span one or more fins and include one or more source/drain regions on which a corresponding contact structure is to be made. In an embodiment, an isolation structure between p-type and n-type fins is selective to the trench etch and therefore remains intact within the trench after the target source/drain regions have been exposed. In such cases, the isolation structure physically separates n-type source/drain regions from p-type source/drain regions. The contact structures on the different type source/drain regions may be shorted proximate the top of the isolation structure. Numerous material systems can be used for the channel and source/drain regions, including germanium, group III-V materials, and 2-D materials.

Abstract: Particular embodiments described herein provide for an electronic device that can include a nanowire channel. The nanowire channel can include nanowires and the nanowires can be about fifteen (15) or less angstroms apart. The nanowire channel can include more than ten (10) nanowires and can be created from a MXene material.

Abstract: Techniques are disclosed for deuterium-based passivation of non-planar transistor interfaces. In some cases, the techniques can include annealing an integrated circuit structure including the transistor in a range of temperatures, pressures, and times in an atmosphere that includes deuterium. In some instances, the anneal process may be performed at pressures of up to 50 atmospheres to increase the amount of deuterium that penetrates the integrated circuit structure and reaches the interfaces to be passivated. Interfaces to be passivated may include, for example, an interface between the transistor conductive channel and bordering transistor gate dielectric and/or an interface between sub-channel semiconductor and bordering shallow trench isolation oxides.

Abstract: Techniques are disclosed for forming transistor devices having reduced parasitic contact resistance relative to conventional devices. The techniques can be implemented, for example, using a standard contact stack such as a series of metals on, for example, silicon or silicon germanium (SiGe) source/drain regions. In accordance with one example such embodiment, an intermediate boron doped germanium layer is provided between the source/drain and contact metals to significantly reduce contact resistance. Numerous transistor configurations and suitable fabrication processes will be apparent in light of this disclosure, including both planar and non-planar transistor structures (e.g., FinFETs), as well as strained and unstrained channel structures. Graded buffering can be used to reduce misfit dislocation. The techniques are particularly well-suited for implementing p-type devices, but can be used for n-type devices if so desired.

Abstract: Material systems for source region, drain region, and a semiconductor body of transistor devices in which the semiconductor body is electrically insulated from an underlying substrate are selected to reduce or eliminate a band to band tunneling (“BTBT”) effect between different energetic bands of the semiconductor body and one or both of the source region and the drain region. This can be accomplished by selecting a material for the semiconductor body with a band gap that is larger than a band gap for material(s) selected for the source region and/or drain region.

Abstract: Techniques are disclosed for forming germanium (Ge)-rich channel transistors including one or more dopant diffusion barrier elements. The introduction of one or more dopant diffusion elements into at least a portion of a given source/drain (S/D) region helps inhibit the undesired diffusion of dopant (e.g., B, P, or As) into the adjacent Ge-rich channel region. In some embodiments, the elements that may be included in a given S/D region to help prevent the undesired dopant diffusion include at least one of tin and relatively high silicon. Further, in some such embodiments, carbon may also be included to help prevent the undesired dopant diffusion. In some embodiments, the one or more dopant diffusion barrier elements may be included in an interfacial layer between a given S/D region and the Ge-rich channel region and/or throughout at least a majority of a given S/D region. Numerous embodiments, configurations, and variations will be apparent.

Abstract: Techniques are disclosed for customization of fin-based transistor devices to provide a diverse range of channel configurations and/or material systems, and within the same integrated circuit die. Sacrificial fins are removed via wet and/or dry etch chemistries configured to provide trench bottoms that are non-faceted and have no or otherwise low-ion damage. The trench is then filled with desired semiconductor material. A trench bottom having low-ion damage and non-faceted morphology encourages a defect-free or low defect interface between the substrate and the replacement material. In an embodiment, each of a first set of the sacrificial silicon fins is recessed and replaced with a p-type material, and each of a second set of the sacrificial fins is recessed and replaced with an n-type material. Another embodiment may include a combination of native fins (e.g., Si) and replacement fins (e.g., SiGe). Another embodiment may include replacement fins all of the same configuration.

Abstract: Integrated circuit transistor structures are disclosed that reduce band-to-band tunneling between the channel region and the source/drain region of the transistor, without adversely increasing the extrinsic resistance of the device. In an example embodiment, the structure includes one or more spacer configured to separate the source and/or drain from the channel region. The spacer(s) regions comprise a semiconductor material that provides a relatively high conduction band offset (CBO) and a relatively low valence band offset (VBO) for PMOS devices, and a relatively high VBO and a relatively low CBO for NMOS devices. In some cases, the spacer includes silicon, germanium, and carbon (e.g., for devices having germanium channel). The proportions may be at least 10% silicon by atomic percentage, at least 85% germanium by atomic percentage, and at least 1% carbon by atomic percentage. Other embodiments are implemented with III-V materials.