Superconducting IC Flux-Directing Layout for Flux Trapping Control

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Superconducting integrated circuits face challenges in high-density element arrangements that effectively trap magnetic flux to mitigate its influence, leading to noise and operational errors due to flux trapping, which affects the performance of quantum processors and classical processors.

Innovation Solution

A superconducting integrated circuit design incorporating a flux-trapping location with aligned apertures and a flux-directing layer, utilizing superconducting materials with different critical temperatures to direct and trap magnetic flux away from sensitive devices during cooldown, thereby isolating it from flux-susceptible components.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If a high-density arrangement of elements is implemented in a superconducting integrated circuit, then the device complexity and integration density are improved, but magnetic flux trapping increases causing noise and operational errors

Engineering Contradiction:
Improveintegration densityVSAvoidmagnetic flux trapping
Core Design Contradiction:
ProductivityVSObject-affected harmful factors

Solution Approach 1:

The patent extracts the harmful magnetic flux from the vicinity of sensitive superconducting elements by introducing dedicated flux-trapping apertures that capture and isolate flux in designated regions, thereby removing the harmful interaction between flux and sensitive elements while maintaining high integration density

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent introduces flux-directing layers as intermediary structures between external magnetic fields and sensitive superconducting elements. These layers guide flux away from sensitive regions toward designated trapping locations, acting as a mediator that controls flux distribution without requiring reduction of element density

Inventive Principle:
Principle #24Intermediary (Mediator)

2Ease of manufacture

If traditional superconducting circuit fabrication methods are used, then manufacturing simplicity is maintained, but flux trapping cannot be effectively controlled leading to increased noise

Engineering Contradiction:
Improvefabrication simplicityVSAvoiduncontrolled flux trapping
Core Design Contradiction:
Ease of manufactureVSObject-affected harmful factors

Solution Approach 1:

The patent implements flux-trapping apertures and flux-directing layers during the fabrication process itself, performing preliminary flux management before the circuit operates. This preliminary structural configuration enables passive flux control without requiring additional active components or complex post-fabrication procedures

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent modifies fabrication parameters by incorporating multi-layer superconducting materials with different critical temperatures and introducing aperture geometries during manufacturing. These parameter changes enable the circuit structure itself to control flux behavior, achieving effective flux management through standard fabrication processes

Inventive Principle:
Principle #35Parameter changes

3Object-affected harmful factors

If flux trapping is increased to shield sensitive devices, then the shielding effectiveness is improved, but this causes operational errors due to excessive flux in the circuit

Engineering Contradiction:
Improveshielding effectivenessVSAvoidoperational accuracy
Core Design Contradiction:
Object-affected harmful factorsVSReliability

Solution Approach 1:

The patent applies local quality by creating spatially differentiated flux management: flux-trapping apertures are strategically positioned near sensitive elements to provide localized shielding, while flux-directing layers guide flux to designated trapping regions. This localized approach provides shielding where needed without introducing excessive flux elsewhere in the circuit

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The patent converts the harmful effect of magnetic flux into a beneficial shielding mechanism by designing flux-trapping apertures that capture flux and use it to create protective flux barriers around sensitive elements. The trapped flux, which would otherwise cause noise, is instead utilized to enhance shielding effectiveness in a controlled manner

Inventive Principle:
Principle #22Blessing in disguise (Convert harm into benefit)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The design effectively reduces flux trapping, minimizing noise and operational errors in superconducting circuits, particularly quantum processors, by directing and trapping flux in safe locations, ensuring stable device performance and accurate computational results.

Implementation Method 1

a first superconducting material having a first critical temperature; a superconducting material having a second critical temperature... as the superconducting integrated circuit is cooled to a temperature that is less than both the first critical temperature and the second critical temperature

Methodology Applied
Scientific EffectSuperconductivity: Superconductivity

Implementation Method 2

the flux-trapping location positioned such that flux trapped within the flux-trapping location is isolated from the first device

Methodology Applied
Scientific EffectMagnetic flux trapping: Magnetic Field

Data Source

PatentEP4070392B1Systems and methods for fabricating superconducting integrated circuits
Publication Date: 2026.02.04 D WAVE SYSTEMS INC
  • EP4070392B1 patent drawingFigure 1
  • EP4070392B1 patent drawingFigure 2A
  • EP4070392B1 patent drawingFigure 2B

AI summary

A system and method for mitigating flux trapping in a superconducting integrated circuit. A first metal layer is formed having a first critical temperature and a first device, and a flux directing layer is formed having a second critical temperature. The flux directing layer is positioned in communication with an aperture location, and the aperture location is spaced from the first device to isolate the first device from flux trapped in the aperture. The superconducting integrated circuit is cooled from a first temperature that is above both the first and second critical temperatures to a second temperature that is less than both the first and second critical temperatures by a cryogenic refrigerator. A relative temperature difference between the first and second critical temperatures causes the flux directing layer to direct flux away from the first device and trap flux at the aperture location.