Superconducting circuit including superconducting qubits

Patent metadata

Field	Value
Publication number	US-12329043-B2
Application number	US-202318446861-A
Country	US
Kind code	B2
Filing date	Aug 9, 2023
Priority date	Jun 6, 2019
Publication date	Jun 10, 2025
Grant date	Jun 10, 2025

Abstract

The present disclosure discloses a device and a method for fabricating a superconducting circuit including a superconducting qubit. The superconducting circuit comprises a bottom electrode interconnecting a superconducting qubit and a first part of the superconducting circuit. The bottom electrode comprises a bottom electrode of the superconducting qubit and a bottom electrode of the first part of the superconducting circuit. The bottom electrode of the superconducting qubit and the bottom electrode of the first part of the superconducting circuit are formed in a first superconducting layer.

First claim

The invention claimed is:

1. A method for preparing a superconducting circuit, comprising:
covering a first area with a first photoresist and covering a second area with a second photoresist, wherein the first area comprises an area where a superconducting qubit of the superconducting circuit is located, the second area comprises an area where a part of the superconducting circuit is located, and the second photoresist covers the first photoresist;
performing lithography on the second photoresist to form the part of the superconducting circuit, and to expose the first photoresist covered by the second photoresist;
performing lithography on the exposed first photoresist to form the superconducting qubit;
depositing a superconducting material on the first area and the second area; and
removing the first photoresist and the second photoresist to obtain the superconducting circuit, wherein the superconducting qubit and the part of the superconducting circuit are connected via a superconducting layer formed by the deposited superconducting material.

2. The method according to claim 1 , wherein
the superconducting qubit is formed through lithography performed on the exposed first photoresist using at least one of the following manners: overlap technique or shadow evaporation technique; and
the part of the superconducting circuit is formed through lithography performed on the second photoresist using at least one of the following manners: lift-off technique, wet etching technique, or dry etching technique.

3. The method according to claim 1 , wherein
the first photoresist comprises an e-beam lithography photoresist, and the second photoresist comprises an optical photoresist.

4. The method according to claim 1 , wherein the superconducting material comprises at least one of the following: aluminum, niobium, niobium nitride, or titanium nitride.

5. A superconducting circuit, comprising:
a top electrode interconnecting a superconducting qubit and a first part of the superconducting circuit, the top electrode comprising:
a top electrode of the superconducting qubit; and
a top electrode of the first part of the superconducting circuit, wherein the top electrode of the first part of the superconducting circuit is integrally formed with the top electrode of the superconducting circuit.

6. The superconducting circuit according to claim 5 , further comprising:
a bottom electrode interconnecting the superconducting qubit and a second part of the superconducting circuit, the bottom electrode comprising:
a bottom electrode of the superconducting qubit; and
a bottom electrode of the second part of the superconducting circuit.

7. The superconducting circuit according to claim 5 , wherein the top electrode of the superconducting qubit and the top electrode of the first part of the superconducting circuit are formed in a first superconducting layer.

8. The superconducting circuit according to claim 7 , wherein the bottom electrode of the superconducting qubit and the bottom electrode of the second part of the superconducting circuit are formed in a second superconducting layer.

9. The superconducting circuit according to claim 8 , wherein the first superconducting layer or the second superconducting layer comprises a metal layer or a superconducting compound layer.

10. The superconducting circuit according to claim 9 , wherein the metal layer or the superconducting compound layer includes at least one of the following: aluminum, niobium, niobium nitride, or titanium nitride.

11. The superconducting circuit according to claim 6 , wherein an insulation layer is provided on an overlapped area between the top electrode and the bottom electrode.

Assignees

• Alibaba Group Holding Ltd

Inventors

• Deng Hao

Classifications

• G06N10/40

  Physical realisations or architectures of quantum processors or components for manipulating qubits, e.g. qubit coupling or qubit control · CPC title

• H10N60/0912

  of Josephson-effect devices · CPC title

• H10N60/12

  Josephson-effect devices · CPC title

• H10N69/00

  Integrated devices, or assemblies of multiple devices, comprising at least one superconducting element covered by group H10N60/00 · CPC title

• H10N60/01

  Manufacture or treatment · CPC title