Abstract: Disclosed herein are quantum dot devices, as well as related computing devices and methods. For example, in some embodiments, a quantum dot device may include: a quantum well stack; a first gate above the quantum well stack, wherein the first gate includes a first gate metal and a first gate dielectric; and a second gate above the quantum well stack, wherein the second gate includes a second gate metal and a second gate dielectric, and the first gate is at least partially between a portion of the second gate and the quantum well stack.

Abstract: An integrated circuit includes an upper semiconductor body extending in a first direction from an upper source region to an upper drain region, and a lower semiconductor body extending in the first direction from a lower source region to a lower drain region. The upper body is spaced vertically from the lower body in a second direction orthogonal to the first direction. A gate spacer structure is adjacent to the upper and lower source regions. In an example, the gate spacer structure includes (i) a first section having a first dimension in the first direction, and (ii) a second section having a second dimension in the first direction. In an example, the first dimension is different from the second dimension by at least 1 nm. In some cases, an intermediate portion of the gate spacer structure extends laterally within a given gate structure, or between upper and lower gate structures.

Abstract: Techniques are provided herein to form non-planar semiconductor devices in a stacked transistor configuration adjacent to stressor materials. In one example, an n-channel device and a p-channel device may both be gate-all-around 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 both ends of the p-channel device. On the opposite side of the stacked source or drain regions (e.g., opposite from the nanoribbons), stressor materials may be used to fill the gate trench in place of additional semiconductor devices. The stressor materials may include, for instance, a compressive stressor material adjacent to the p-channel device and/or a tensile stressor material adjacent to the n-channel device. The stressor material(s) may form or otherwise be part of a diffusion cut structure.

Abstract: An integrated circuit structure includes a device layer including an upper device above a lower device. The upper device includes an upper source or drain region, and an upper source or drain contact coupled to the upper source or drain region. The lower device includes a lower source or drain region. A first conductive feature is below the device layer, where the first conductive feature is coupled to the lower source or drain region. A second conductive feature vertically extends through the device layer. In an example, the second conductive feature is to couple (i) the first conductive feature below the device layer and (ii) an interconnect structure above the device layer. Thus, the first and second conductive features facilitate a connection between the interconnect structure on the frontside of the integrated circuit and the lower source or drain region towards the backside of the integrated circuit.

Abstract: An integrated circuit structure includes a second device stacked vertically above a first device. The first device includes (i) a first source or drain region, (ii) a first source or drain contact coupled to the first source or drain region, and (iii) a first layer comprising a first metal and first one or more semiconductor materials between at least a section of the first source or drain region and the first source or drain contact. The second device includes (i) a second source or drain region, (ii) a second source or drain contact coupled to the second source or drain region, and (iii) a second layer comprising a second metal and second one or more semiconductor materials between at least a section of the second source or drain region and the second source or drain contact. In an example, the first metal and the second metal are different.

Abstract: A semiconductor structure includes a second device stacked over a first device. In an example, the first device includes (i) a first source region, (ii) a first drain region, (iii) a body including a semiconductor material extending laterally from the first source region to the first drain region, and (iv) a first gate structure at least in part wrapped around the body. The body can be, for instance, a nanoribbon, nanosheet, or nanowire. In an example, the second device comprises (i) a second source region, (ii) a second drain region, and (iii) a second gate structure at least in part laterally between the second source region and the second drain region. In an example, the second device lacks a continuous body extending laterally from the second source region to the second drain region.

Abstract: A semiconductor structure includes an upper device stacked over a lower device. In an example, the upper device includes (i) a first source region, (ii) a first drain region, (iii) a body of semiconductor material extending laterally from the first source region to the first drain region, and (iv) a first gate structure at least in part wrapped around the body. In an example, the lower device includes (i) a second source region, (ii) a second drain region, and (iii) a second gate structure at least in part laterally between the second source region and the second drain region. In an example, the lower device lacks a body of semiconductor material extending laterally from the second source region to the second drain region. In another example, the upper device lacks a body of semiconductor material extending laterally from the first source region to the first drain region.

Abstract: Disclosed herein are quantum dot devices, as well as related computing devices and methods. For example, in some embodiments, a quantum dot device may include: a quantum well stack; a first gate and an adjacent second gate above the quantum well stack; and a gate wall between the first gate and the second gate, wherein the gate wall includes a spacer and a capping material, the spacer has a top and a bottom, the bottom of the spacer is between the top of the spacer and the quantum well stack, and the capping material is proximate to the top of the spacer.

Abstract: Quantum dot devices, and related systems and methods, are disclosed herein. In some embodiments, a quantum dot device may include a quantum well stack; a plurality of first gates above the quantum well stack; and a plurality of second gates above the quantum well stack; wherein the plurality of first gates are arranged in electrically continuous rows extending in a first direction, and the plurality of second gates are arranged in electrically continuous rows extending in a second direction perpendicular to the first direction.

Abstract: Disclosed herein are quantum dot devices, as well as related computing devices and methods. For example, in some embodiments, a quantum dot device may include: a quantum well stack including a quantum well layer, wherein the quantum well layer includes an isotopically purified material; a gate dielectric above the quantum well stack; and a gate metal above the gate dielectric, wherein the gate dielectric is between the quantum well layer and the gate metal.

Abstract: Disclosed herein are quantum dot devices with multiple layers of gate metal, as well as related computing devices and methods. For example, in some embodiments, a quantum dot device may include: a quantum well stack; an insulating material above the quantum well stack, wherein the insulating material includes a trench; and a gate on the insulating material and extending into the trench, wherein the gate includes a first gate metal in the trench and a second gate metal above the first gate metal.

Abstract: Quantum dot devices, and related systems and methods, are disclosed herein. In some embodiments, a quantum dot device may include a quantum well stack; a plurality of first gates above the quantum well stack; and a plurality of second gates above the quantum well stack; wherein the plurality of first gates are arranged in electrically continuous rows extending in a first direction, and the plurality of second gates are arranged in electrically continuous rows extending in a second direction perpendicular to the first direction.

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: Quantum dot devices and related methods and systems that use semiconductor nanoribbons arranged in a grid where a plurality of first nanoribbons, substantially parallel to one another, intersect a plurality of second nanoribbons, also substantially parallel to one another but at an angle with respect to the first nanoribbons, are disclosed. Different gates at least partially wrap around individual portions of the first and second nanoribbons, and at least some of the gates are provided at intersections of the first and second nanoribbons. Unlike previous approaches to quantum dot formation and manipulation, nanoribbon-based quantum dot devices provide strong spatial localization of the quantum dots, good scalability in the number of quantum dots included in the device, and/or design flexibility in making electrical connections to the quantum dot devices to integrate the quantum dot devices in larger computing devices.

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: 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 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: An integrated circuit includes a lower and upper device portions including bodies of semiconductor material extending horizontally between first source and drain regions in a spaced-apart vertical stack. A first gate structure is around a body in the lower device portion and includes a first gate electrode and a first gate dielectric. A second gate structure is around a body in the upper device portion and includes a second gate electrode and a second gate dielectric, where the first gate dielectric is compositionally distinct from the second gate dielectric. In some embodiments, a dipole species has a first concentration in the first gate dielectric and a different second concentration in the second gate dielectric. A method of fabrication is also disclosed.

Abstract: Disclosed herein are quantum dot devices, as well as related computing devices and methods. For example, in some embodiments, a quantum dot device may include: a quantum well stack and a plurality of linear arrays of gates above the quantum well stack to control quantum dot formation in the quantum well stack. An insulating material may be between a first linear array of gates and a second linear array of gates, the insulating material may be between individual gates in the first linear array of gates, and gate metal of the first linear array of gates may extend over the insulating material.

Abstract: Disclosed herein are quantum dot devices, as well as related computing devices and methods. For example, in some embodiments, a quantum dot device may include a (111) silicon substrate, a (111) germanium quantum well layer above the substrate, and a plurality of gates above the quantum well layer. In some embodiments, a quantum dot device may include a silicon substrate, an insulating material above the silicon substrate, a quantum well layer above the insulating material, and a plurality of gates above the quantum well layer.