Abstract: Disclosed herein are tri-gate transistor arrangements, and related methods and devices. For example, in some embodiments, a transistor arrangement may include a fin stack shaped as a fin extending away from a base, and a subfin dielectric stack. The fin includes a subfin portion and a channel portion, the subfin portion being closer to the base than the channel portion. The subfin dielectric stack includes a transistor dielectric material, and a fixed charge liner material disposed between the transistor dielectric material and the subfin portion of the fin.

Abstract: Gate-all-around integrated circuit structures having depopulated channel structures, and methods of fabricating gate-all-around integrated circuit structures having depopulated channel structures using multiple bottom-up oxidation approaches, are described. For example, an integrated circuit structure includes a vertical arrangement of nanowires. All nanowires of the vertical arrangement of nanowires are oxide nanowires. A gate stack is over the vertical arrangement of nanowires, around each of the oxide nanowires. The gate stack includes a conductive gate electrode.

Abstract: Embodiments of the present disclosure may generally relate to systems, apparatus, and/or processes to form volumes of oxide within a fin, such as a Si fin. In embodiments, this may be accomplished by applying a catalytic oxidant material on a side of a fin and then annealing to form a volume of oxide. In embodiments, this may be accomplished by using a plasma implant technique or a beam-line implant technique to introduce oxygen ions into an area of the fin and then annealing to form a volume of oxide. Processes described here may be used manufacture a transistor, a stacked transistor, or a three-dimensional (3-D) monolithic stacked transistor.

Abstract: Embodiments herein describe techniques, systems, and method for a semiconductor device. Embodiments herein may present a semiconductor device having a channel area including a channel III-V material, and a source area including a first portion and a second portion of the source area. The first portion of the source area includes a first III-V material, and the second portion of the source area includes a second III-V material. The channel III-V material, the first III-V material and the second III-V material may have a same lattice constant. Moreover, the first III-V material has a first bandgap, and the second III-V material has a second bandgap, the channel III-V material has a channel III-V material bandgap, where the channel material bandgap, the second bandgap, and the first bandgap form a monotonic sequence of bandgaps. Other embodiments may be described and/or claimed.

Abstract: Stacked transistor structures having a conductive interconnect between source/drain regions of upper and lower transistors. In some embodiments, the interconnect is provided, at least in part, by highly doped epitaxial material deposited in the upper transistor's source/drain region. In such cases, the epitaxial material seeds off of an exposed portion of semiconductor material of or adjacent to the upper transistor's channel region and extends downward into a recess that exposes the lower transistor's source/drain contact structure. The epitaxial source/drain material directly contacts the lower transistor's source/drain contact structure, to provide the interconnect. In other embodiments, the epitaxial material still seeds off the exposed semiconductor material of or proximate to the channel region and extends downward into the recess, but need not contact the lower contact structure.

Abstract: A device is disclosed. The device includes a first epitaxial region, a second epitaxial region, a first gate region between the first epitaxial region and a second epitaxial region, a first dielectric structure underneath the first epitaxial region, a second dielectric structure underneath the second epitaxial region, a third epitaxial region underneath the first epitaxial region, a fourth epitaxial region underneath the second epitaxial region, and a second gate region between the third epitaxial region and a fourth epitaxial region and below the first gate region. The device also includes, a conductor via extending from the first epitaxial region, through the first dielectric structure and the third epitaxial region, the conductor via narrower at an end of the conductor via that contacts the first epitaxial region than at an opposite end.

Abstract: Embodiments herein describe techniques, systems, and method for a semiconductor device. A semiconductor device may include isolation areas above a substrate to form a trench between the isolation areas. A first buffer layer is over the substrate, in contact with the substrate, and within the trench. A second buffer layer is within the trench over the first buffer layer, and in contact with the first buffer layer. A channel area is above the first buffer layer, above a portion of the second buffer layer that are below a source area or a drain area, and without being vertically above a portion of the second buffer layer. In addition, the source area or the drain area is above the second buffer layer, in contact with the second buffer layer, and adjacent to the channel area. Other embodiments may be described and/or claimed.

Abstract: Techniques are provided herein to form semiconductor devices having a frontside and backside contact in an epi region of a stacked transistor configuration. In one example, an n-channel device and a p-channel device may both be GAA transistors where the n-channel device is located vertically above the p-channel device (or vice versa). Source or drain regions are adjacent to both ends of the n-channel device and the p-channel device. Deep and narrow contacts may be formed from both the frontside and the backside of the integrated circuit through the stacked source or drain regions. The contacts may physically contact each other to form a combined contact that extends through an entirety of the stacked source or drain regions. The higher contact area provided to both source or drain regions provides a more robust ohmic contact with a lower contact resistance compared to previous contact architectures.

Abstract: Techniques are provided herein to form gate-all-around (GAA) semiconductor devices utilizing a metal fill in an epi region of a stacked transistor configuration. In one example, an n-channel device and the p-channel device may both be GAA transistors each having any number of nanoribbons extending in the same direction where the n-channel device is located vertically above the p-channel device (or vice versa). Source or drain regions are adjacent to both ends of the n-channel device and the p-channel device. A metal fill may be provided around the source or drain region of the bottom semiconductor device to provide a high contact area between the highly conductive metal fill and the epitaxial material of that source or drain region. Metal fill may also be used around the top source or drain region to further improve conductivity throughout both of the stacked source or drain regions.

Abstract: Techniques to form wrap-around contacts in a stacked transistor architecture. An example includes a first source or drain region and a second source or drain region spaced from and over the first source or drain region. A conductive contact is on a top surface of the second source or drain and extends down one or more side surfaces of the second source or drain region such that the conductive contact is laterally adjacent to a bottom surface of the second source or drain region. In some cases, the conductive contact is also on a top surface of the first source or drain region, and/or extends down a side surface of the first source or drain region. In some cases, a second conductive contact is on a bottom surface of the first source or drain region, and may extend up a side surface the first source or drain region.

Abstract: Techniques are provided herein to form semiconductor devices having a non-reactive metal contact in an epi region of a stacked transistor configuration. An n-channel device may be located vertically above a p-channel device (or vice versa). Source or drain regions are adjacent to both ends of the n-channel device and the p-channel device, such that a source or drain region of one device is located vertically over the source or drain region of the other device. A deep and narrow contact may be formed from either the frontside or the backside of the integrated circuit through the stacked source or drain regions. According to some embodiments, the contact is formed using a refractory metal or other non-reactive metal such that no silicide or germanide is formed with the epi material of the source or drain regions at the boundary between the contact and the source or drain regions.

Abstract: Disclosed herein are stacked transistors having device strata with different channel widths, as well as related methods and devices. In some embodiments, an integrated circuit structure may include stacked strata of transistors, wherein different channel materials of different strata have different widths.

Abstract: Techniques are provided herein to form semiconductor devices having a stacked transistor configuration. An n-channel device and a p-channel device may both be gate-all-around (GAA) transistors each having any number of nanoribbons extending in the same direction where one device is located vertically above the other device. According to some embodiments, the n-channel device and the p-channel device conductively share the same gate, and a width of the gate structure around one device is greater than the width of the gate structure around the other device. According to some other embodiments, the n-channel device and the p-channel device each have a separate gate structure that is isolated from the other using a dielectric layer between them. A gate contact is adjacent to the upper device and contacts the gate structure of the other lower device.

Abstract: A device is disclosed. The device includes a first semiconductor fin, a first source-drain epitaxial region adjacent a first portion of the first semiconductor fin, a second source-drain epitaxial region adjacent a second portion of the first semiconductor fin, a first gate conductor above the first semiconductor fin, a gate spacer covering the sides of the gate conductor, a second semiconductor fin below the first semiconductor fin, a second gate conductor on a first side of the second semiconductor fin and a third gate conductor on a second side of the second semiconductor fin, a third source-drain epitaxial region adjacent a first portion of the second semiconductor fin, and a fourth source-drain epitaxial region adjacent a second portion of the second semiconductor fin. The device also includes a dielectric isolation structure below the first semiconductor fin and above the second semiconductor fin that separates the first semiconductor fin and the second semiconductor fin.

Abstract: Techniques are provided herein to form semiconductor devices having backside contacts. Sacrificial plugs are formed first within a substrate at particular locations to align with source and drain regions during a later stage of processing. Another wafer is subsequently bonded to the surface of the substrate and is thinned to effectively transfer different material layers to the top surface of the substrate. One of the transferred layers acts as a seed layer for the growth of additional semiconductor material used to form semiconductor devices. The source and drain regions of the semiconductor devices are sufficiently aligned over the previously formed sacrificial plugs. A backside portion of the substrate may be removed to expose the sacrificial plugs from the backside. Removal of the plugs and replacement of the recesses left behind with conductive material forms the conductive backside contacts to the source or drain regions.

Abstract: A device is disclosed. The device includes a first epitaxial region, a second epitaxial region, a first gate region between the first epitaxial region and a second epitaxial region, a first dielectric structure underneath the first epitaxial region, a second dielectric structure underneath the second epitaxial region, a third epitaxial region underneath the first epitaxial region, a fourth epitaxial region underneath the second epitaxial region, and a second gate region between the third epitaxial region and a fourth epitaxial region and below the first gate region. The device also includes, a conductor via extending from the first epitaxial region, through the first dielectric structure and the third epitaxial region, the conductor via narrower at an end of the conductor via that contacts the first epitaxial region than at an opposite end.

Abstract: A gate-all-around transistor device includes a body including a semiconductor material, and a gate structure at least in part wrapped around the body. The gate structure includes a gate electrode and a gate dielectric between the body and the gate electrode. The body is between a source region and a drain region. A first spacer is between the source region and the gate electrode, and a second spacer is between the drain region and the gate electrode. In an example, the first and second spacers include germanium and oxygen. The body can be, for instance, a nanoribbon, nanosheet, or nanowire.

Abstract: Techniques are provided herein to form gate-all-around (GAA) semiconductor devices, such as those having a stacked transistor configuration. In one example case, two different semiconductor devices may both be GAA transistors each having any number of nanoribbons extending in the same (e.g., horizontal) direction where one device is located vertically above the other device. An internal spacer structure extends between the nanoribbons of both devices along the vertical direction, where the spacer structure includes one or more rib features between the two devices. A gate structure that includes one or more gate dielectric layers and one or more gate electrode layers may be formed around the nanoribbons of both devices, in some cases. In other cases, a split-gate configuration is used where upper and lower gate structures are separated by an isolation structure. Forksheet transistors and other GAA configurations may be formed using the techniques as well.

Abstract: Techniques are provided herein to form semiconductor devices having a stacked transistor configuration. In an example, an upper (e.g., n-channel) device and a lower (e.g., p-channel) device may both be gate-all-around (GAA) transistors each having any number of nanoribbons extending in the same direction where the upper device is located vertically above the lower device. According to some embodiments, an internal spacer structure extends between the nanoribbons of the upper device and the nanoribbons of the lower device along the vertical direction, where the spacer structure has a stepwise or an otherwise outwardly protruding profile as it extends between the nanoribbons of the upper device and the lower device. Accordingly, in one example, a gate structure formed around the nanoribbons of both the n-channel device and the p-channel device exhibits a greater width in the region between the nanoribbons of the n-channel device and the nanoribbons of the p-channel device.

Abstract: An integrated circuit structure comprises a lower device layer that includes a first structure comprising a plurality of PMOS transistors. An upper device layer is formed on the lower device layer, wherein the upper device layer includes a second structure comprising a plurality of NMOS transistors having a group III-V material source/drain region.