Abstract: Techniques related to vertical silicon-on-metal superconducting quantum interference devices and method of fabricating the same are provided. Also provided are associated flux control and biasing circuitry. A superconductor structure can comprise a silicon-on-metal substrate that can comprise a first superconducting layer, comprising a first superconducting material, between a first crystalline silicon layer and a second crystalline silicon layer. The superconducting structure can also comprise a first via comprising a first Josephson junction and a second via comprising a second Josephson junction. The first via and the second via can be formed between the first superconducting layer and a second superconducting layer, comprising a second superconducting material.

Abstract: Techniques related to a three-dimensional integration for qubits on multiple height crystalline dielectric and method of fabricating the same are provided. A superconductor structure can comprise a first buried layer that can comprise a first patterned superconducting layer of a first wafer bonded to a second patterned superconducting layer of a second wafer. The superconductor structure can also comprise a patterned superconducting film attached to the second wafer. Further, the superconductor structure can comprise a second buried layer that can comprise a third patterned superconducting layer of a third wafer bonded to the patterned superconducting film that can be attached to the second wafer.

Abstract: A technique relates to correcting an area of overlap between two films created by sequential shadow mask evaporations. At least one process is performed of: correcting design features in an original layout to generate a corrected layout using a software tool, such that the corrected layout modifies shapes of the design features and correcting the design features in the original layout to generate the corrected layout using a lithographic tool, such that the corrected layout modifies the shapes of the design features. The modified shapes of the design features are patterned at locations on a wafer according to the corrected layout using the lithographic tool. A first film is deposited by an initial shadow mask evaporation and a second film by a subsequent shadow mask evaporation to produce corrected junctions at the locations on the wafer, such that the first film and the second film have an overlap.

Abstract: Techniques related to a three-dimensional integration for qubits on crystalline dielectric and method of fabricating the same are provided. A superconductor structure can comprise a first wafer comprising a first crystalline silicon layer attached to a first patterned superconducting layer, and a second wafer comprising a second crystalline silicon layer attached to a second patterned superconducting layer. The second patterned superconducting layer of the second wafer can be attached to the first patterned superconducting layer of the first wafer. A buried layer can comprise the first patterned superconducting layer and the second patterned superconducting layer. The buried layer can comprise one or more circuits. The superconductor structure can also comprise a transmon qubit that can comprise a Josephson junction and one or more capacitor pads comprising superconducting material. The Josephson junction can comprise a first superconductor contact, a tunnel barrier layer, and a second superconductor contact.

Abstract: Techniques related to a three-dimensional integration for qubits on crystalline dielectric and method of fabricating the same are provided. A superconductor structure can comprise a first wafer comprising a first crystalline silicon layer attached to a first patterned superconducting layer, and a second wafer comprising a second crystalline silicon layer attached to a second patterned superconducting layer. The second patterned superconducting layer of the second wafer can be attached to the first patterned superconducting layer of the first wafer. A buried layer can comprise the first patterned superconducting layer and the second patterned superconducting layer. The buried layer can comprise one or more circuits. The superconductor structure can also comprise a transmon qubit that can comprise a Josephson junction and one or more capacitor pads comprising superconducting material. The Josephson junction can comprise a first superconductor contact, a tunnel barrier layer, and a second superconductor contact.

Abstract: The present invention provides a process and structure of microfabricated air bridges for planar microwave resonator circuits. In an embodiment, the invention includes depositing a superconducting film on a surface of a base material, where the superconducting film is formed with a compressive stress, where the compressive stress is higher than a critical buckling stress of a defined structure, etching an exposed area of the superconducting film, thereby creating the at least one bridge, etching the base material, thereby forming a gap between the at least one bridge and the base material, depositing the at least one metal line on at least part of the superconducting film and at least part of the base material, where the at least one metal line runs under the bridge.

Abstract: Techniques related to a three-dimensional integration for qubits on multiple height crystalline dielectric and method of fabricating the same are provided. A superconductor structure can comprise a first buried layer that can comprise a first patterned superconducting layer of a first wafer bonded to a second patterned superconducting layer of a second wafer. The superconductor structure can also comprise a patterned superconducting film attached to the second wafer. Further, the superconductor structure can comprise a second buried layer that can comprise a third patterned superconducting layer of a third wafer bonded to the patterned superconducting film that can be attached to the second wafer.

Abstract: The present invention provides a process and structure of microfabricated air bridges for planar microwave resonator circuits. In an embodiment, the invention includes depositing a superconducting film on a surface of a base material, where the superconducting film is formed with a compressive stress, where the compressive stress is higher than a critical buckling stress of a defined structure, etching an exposed area of the superconducting film, thereby creating the at least one bridge, etching the base material, thereby forming a gap between the at least one bridge and the base material, depositing the at least one metal line on at least part of the superconducting film and at least part of the base material, where the at least one metal line runs under the bridge.

Abstract: Techniques for a vertical Josephson junction superconducting device are provided. In one embodiment, a chip surface base device structure is provided that comprises a substrate comprising crystalline silicon that is coupled with a first superconducting layer, wherein the first superconducting layer is coupled with a second substrate comprising crystalline silicon. In one implementation, the chip surface base device structure also comprises a vertical Josephson junction located in an etched region of the substrate, the vertical Josephson junction comprising a first superconducting layer, a tunnel barrier layer, and a top superconducting layer.

Abstract: Techniques for a vertical transmon qubit device are provided. In one embodiment, a chip surface base device structure is provided that comprises a first superconducting material physically coupled to a crystalline substrate, wherein the crystalline substrate is physically coupled to a second superconducting material, wherein the second superconducting material is physically coupled to a second crystalline substrate. In one implementation, the chip surface base device structure also comprises a vertical Josephson junction located in a via of the crystalline substrate, the vertical Josephson junction comprising the first superconducting material, a tunnel barrier, and the second superconducting material. In one implementation, the chip surface base device structure also comprises a transmon qubit comprising the vertical Josephson junction and a capacitor formed between the first superconducting material and the second superconducting material.

Abstract: Techniques for a vertical Josephson junction superconducting device using microstrip waveguides are provided. In one embodiment, a chip surface base device structure is provided that comprises a superconducting material located on a first side of a substrate, and a second superconducting material located on a second side of the substrate and stacked on a second substrate, wherein the first side of the substrate and the second side of the substrate are opposite sides. In one implementation, the substrate or the second substrate, or the substrate and the second substrate are crystalline silicon. In one implementation, the chip surface base device structure also comprises a transmon qubit comprising a capacitor and a Josephson junction formed in a via of the substrate and comprising a tunnel barrier. In one implementation, the chip surface base device structure also comprises a microstrip line electrically coupled to the transmon qubit.

Abstract: A technique relates to forming a sidewall tunnel junction. A first conducting layer is formed using a first shadow mask evaporation. A second conducting layer is formed on a portion of the first conducting layer, where the second conducting layer is formed using a second shadow mask evaporation. An oxide layer is formed on the first conducting layer and the second conducting layer. A third conducting layer is formed on part of the oxide layer, such that the sidewall tunnel junction is positioned between the first conducting layer and the third conducting layer.

Abstract: A technique relates to a superconducting chip. Resonant units have resonant frequencies, and the resonant units are configured as superconducting resonators. Josephson junctions are in the resonant units, and one or more of the Josephson junctions have a shorted tunnel barrier.

Abstract: A technique relates to forming a sidewall tunnel junction. A first conducting layer is formed using a first shadow mask evaporation. A second conducting layer is formed on a portion of the first conducting layer, where the second conducting layer is formed using a second shadow mask evaporation. An oxide layer is formed on the first conducting layer and the second conducting layer. A third conducting layer is formed on part of the oxide layer, such that the sidewall tunnel junction is positioned between the first conducting layer and the third conducting layer.

Abstract: A technique relates to a structure. A first surface includes an inductive element of a resonator. A second surface includes a first portion of a capacitive element of the resonator and at least one qubit. A second portion of the capacitive element of the resonator is on the first surface.

Abstract: A technique relates to forming a sidewall tunnel junction. A first conducting layer is formed using a first shadow mask evaporation. A second conducting layer is formed on a portion of the first conducting layer, where the second conducting layer is formed using a second shadow mask evaporation. An oxide layer is formed on the first conducting layer and the second conducting layer. A third conducting layer is formed on part of the oxide layer, such that the sidewall tunnel junction is positioned between the first conducting layer and the third conducting layer.

Abstract: A technique relates to forming a sidewall tunnel junction. A first conducting layer is formed using a first shadow mask evaporation. A second conducting layer is formed on a portion of the first conducting layer, where the second conducting layer is formed using a second shadow mask evaporation. An oxide layer is formed on the first conducting layer and the second conducting layer. A third conducting layer is formed on part of the oxide layer, such that the sidewall tunnel junction is positioned between the first conducting layer and the third conducting layer.

Abstract: A quantum bit (qubit) flip chip assembly may be formed when a qubit it formed on a first chip and an optically transmissive path is formed on a second chip. The two chips may be bonded using solder bumps. The optically transmissive path may provide optical access to the qubit on the first chip.

Abstract: Generating a layout for a multi-qubit chip is provided. A schematic is received as input. The schematic input includes a plurality of qubits, a plurality of coupling busses, a bus design parameter specifying a bus frequency, a plurality of readout busses, and a plurality of readout ports. A qubit design is selected from a qubit library, based on the qubit style in the schematic input. A bus style is selected from a bus information library, based on the bus style in the schematic input. A qubit layout is automatically generated by assembling the selected bus style/, selected qubit design, the plurality of readout busses and the plurality of readout ports.

Abstract: Verifying a quantum circuit layout design is provided. A qubit layout is received as input. The qubit layout is generated from a qubit schematic. The qubit schematic includes a plurality of qubits, a plurality of coupling buses, a plurality of readout buses, and a plurality of readout ports. Design rules checking is performed on the qubit layout input, using a predefined set of design rule. The bus style/frequency and qubit information are extracted from the qubit layout input. A new qubit schematic is generated from the extracted bus style/frequency and qubit information. The qubit layout is verified based on the new qubit schematic being the same as the qubit schematic.