Abstract: Methods of forming germanium channel structure are described. An embodiment includes forming a germanium fin on a substrate, wherein a portion of the germanium fin comprises a germanium channel region, forming a gate material on the germanium channel region, and forming a graded source/drain structure adjacent the germanium channel region. The graded source/drain structure comprises a germanium concentration that is higher adjacent the germanium channel region than at a source/drain contact region.

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 Ge/SiGe-channel and III-V-channel transistors on the same die. The techniques include depositing a pseudo-substrate of Ge/SiGe or III-V material on a Si or insulator substrate. The pseudo-substrate can then be patterned into fins and a subset of the fins can be replaced by the other of Ge/SiGe or III-V material. The Ge/SiGe fins can be used for p-MOS transistors and the III-V material fins can be used for n-MOS transistors, and both sets of fins can be used for CMOS devices, for example. In some instances, only the channel region of the subset of fins are replaced during, for example, a replacement gate process. In some instances, some or all of the fins may be formed into or replaced by one or more nanowires or nanoribbons.

Abstract: A method including forming a fin of a nonplanar device on a substrate, the fin including a second layer between a first layer and a third layer; replacing the second layer with a dielectric material; and forming a gate stack on a channel region of the fin. An apparatus including a first multigate device on a substrate including a fin including a conducting layer on a dielectric layer, a gate stack disposed on the conducting layer in a channel region of the fin, and a source and a drain formed in the fin, and a second multigate device on the substrate including a fin including a first conducting layer and a second conducting layer separated by a dielectric layer, a gate stack disposed the first conducting layer and the second conducting layer in a channel region of the fin, and a source and a drain formed in the fin.

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. In accordance with an embodiment, sacrificial fins are cladded and then removed thereby leaving the cladding layer as a pair of standalone fins. Once the sacrificial fin areas are filled back in with a suitable insulator, the resulting structure is fin-on-insulator. The new fins can be configured with any materials by using such a cladding-on-core approach. The resulting fin-on-insulator structure is favorable, for instance, for good gate control while eliminating or otherwise reducing sub-channel source-to-drain (or drain-to-source) leakage current. In addition, parasitic capacitance from channel-to-substrate is significantly reduced.

Abstract: Techniques are disclosed for forming p-MOS transistors having one or more carbon-based interface layers between epitaxially grown S/D regions and the channel region. In some cases, the carbon-based interface layer(s) may comprise a single layer having a carbon content of greater than 20% carbon and a thickness of 0.5-8 nm. In some cases, the carbon-based interface layer(s) may comprise a single layer having a carbon content of less than 5% and a thickness of 2-10 nm. In some such cases, the single layer may also comprise boron-doped silicon (Si:B) or boron-doped silicon germanium (SiGe:B). In some cases, one or more additional interface layers may be deposited on the carbon-based interface layer(s), where the additional interface layer(s) comprises Si:B and/or SiGe:B. The techniques can be used to improve short channel effects and improve the effective gate length of a resulting transistor.

Abstract: Techniques are disclosed for reducing off-state leakage of fin-based transistors through the use of a sub-fin passivation layer. In some cases, the techniques include forming sacrificial fins in a bulk silicon substrate and depositing and planarizing shallow trench isolation (STI) material, removing and replacing the sacrificial silicon fins with a replacement material (e.g., SiGe or III-V material), removing at least a portion of the STI material to expose the sub-fin areas of the replacement fins, applying a passivating layer/treatment/agent to the exposed sub-fins, and re-depositing and planarizing additional STI material. Standard transistor forming processes can then be carried out to complete the transistor device. The techniques generally provide the ability to add arbitrary passivation layers for structures that are grown in STI-based trenches. The passivation layer inhibits sub-fin source-to-drain (and drain-to-source) current leakage.

Abstract: Techniques are disclosed for resistance reduction in p-MOS transistors having epitaxially grown boron-doped silicon germanium (SiGe:B) S/D regions. The techniques can include growing one or more interface layers between a silicon (Si) channel region of the transistor and the SiGe:B replacement S/D regions. The one or more interface layers may include: a single layer of boron-doped Si (Si:B); a single layer of SiGe:B, where the Ge content in the interface layer is less than that in the resulting SiGe:B S/D regions; a graded layer of SiGe:B, where the Ge content in the alloy starts at a low percentage (or 0%) and is increased to a higher percentage; or multiple stepped layers of SiGe:B, where the Ge content in the alloy starts at a low percentage (or 0%) and is increased to a higher percentage at each step. Inclusion of the interface layer(s) reduces resistance for on-state current flow.

Abstract: Techniques are disclosed for forming transistors on the same substrate with varied channel materials. The techniques include forming a replacement material region in the substrate, such region used to form a plurality of fins therefrom, the fins used to form transistor channel regions. In an example case, the substrate may comprise Si and the replacement materials may include Ge, SiGe, and/or at least one III-V material. The replacement material regions can have a width sufficient to ensure a substantially planar interface between the replacement material and the substrate material. Therefore, the fins formed from the replacement material regions can also have a substantially planar interface between the replacement material and the substrate material. One example benefit from being able to form replacement material channel regions with such substantially planar interfaces can include at least a 30 percent improvement in current flow at a fixed voltage.

Abstract: An embodiment includes an apparatus comprising: a fin structure on a substrate, the fin structure including fin top and bottom portions, a channel including a majority carrier, and an epitaxial (EPI) layer; an insulation layer including insulation layer top and bottom portions adjacent the fin top and bottom portions; wherein (a) the EPI layer comprises one or more of group IV and III-V materials, (b) the fin bottom portion includes a fin bottom portion concentration of dopants of opposite polarity to the majority carrier, (c) the fin top portion includes a fin top portion concentration of the dopants less than the fin bottom portion concentration, (d) the insulation layer bottom portion includes an insulation layer bottom portion concentration of the dopants, and (e) the insulation layer top portion includes an insulation top layer portion concentration greater than the insulation bottom portion concentration. Other embodiments are described herein.

Abstract: Techniques are disclosed for forming Ge/SiGe-channel and III-V-channel transistors on the same die. The techniques include depositing a pseudo-substrate of Ge/SiGe or III-V material on a Si or insulator substrate. The pseudo-substrate can then be patterned into fins and a subset of the fins can be replaced by the other of Ge/SiGe or III-V material. The Ge/SiGe fins can be used for p-MOS transistors and the III-V material fins can be used for n-MOS transistors, and both sets of fins can be used for CMOS devices, for example. In some instances, only the channel region of the subset of fins are replaced during, for example, a replacement gate process. In some instances, some or all of the fins may be formed into or replaced by one or more nanowires or nanoribbons.