Superconducting Device Stress Reduction Dummy Elements

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

CMOS-based semiconductor devices face limitations in device size and high power consumption due to leakage current, even when inactive, leading to significant energy wastage in applications like data center servers.

Innovation Solution

The development of superconducting devices using reciprocal quantum logic (RQL) circuits with Josephson junctions and strain reservoir structures to mitigate thermal expansion mismatch issues, enabling zero static power dissipation and reduced stress at metal-dielectric interfaces.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If CMOS technology is used for semiconductor devices, then device integration is achieved, but leakage current causes high power consumption even when inactive

Engineering Contradiction:
Improvedevice integrationVSAvoidpower consumption
Core Design Contradiction:
ProductivityVSLoss of energy

Solution Approach 1:

The patent replaces the conventional CMOS electronic switching mechanism with a superconducting quantum interference device (SQUID) based logic system. This substitution eliminates resistive power loss by using quantum interference effects in superconducting loops to perform logical operations, achieving zero static power dissipation while maintaining computational functionality.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The invention changes the fundamental operating parameters from conventional voltage-based CMOS switching to magnetic flux-based superconducting quantum interference. By operating at cryogenic temperatures and utilizing quantum mechanical effects, the system achieves dramatically reduced power consumption while maintaining device integration capability.

Inventive Principle:
Principle #35Parameter changes

2Reliability

If multi-metallic wiring layers are used in superconducting circuits, then resistance to impurity diffusion and surface passivation are improved, but manufacturing complexity increases

Engineering Contradiction:
Improveimpurity diffusion resistanceVSAvoidwiring layer structure
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent employs multi-metallic composite wiring structures where different metal layers are stacked to provide complementary functions. The niobium layer provides superconductivity, while the tungsten layer provides mechanical stability and stress management. This composite approach enhances impurity diffusion resistance and surface passivation while the standardized fabrication process keeps manufacturing complexity manageable.

Inventive Principle:
Principle #40Composite materials

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

RQL circuits achieve zero static power dissipation and eliminate ground return current by using AC power, while strain reservoirs reduce mechanical stress, enhancing the performance and reliability of superconducting devices.

Implementation Method 1

superconducting devices using reciprocal quantum logic (RQL) circuits with Josephson junctions

Methodology Applied
Scientific EffectJosephson effect: Josephson Effect

Implementation Method 2

strain reservoir structures to mitigate thermal expansion mismatch issues, reducing mechanical stress

Methodology Applied
Scientific EffectThermal expansion: Thermal Expansion

Implementation Method 3

superconducting devices using reciprocal quantum logic (RQL) circuits

Methodology Applied
Scientific EffectSuperconductivity: Superconductivity

Data Source

PatentEP3488475B1Superconducting device with stress reducing dummy elements
Publication Date: 2020.10.14 MICROSOFT TECHNOLOGY LICENSING LLC
  • EP3488475B1 patent drawingFigure 1~3
  • EP3488475B1 patent drawingFigure 4~6
  • EP3488475B1 patent drawingFigure 7~8

AI summary

The proposed superconducting device, compatible with reciprocal quantum logic (RQL) Josephson junction circuits, includes a superconducting element having a first coefficient of thermal expansion formed on a dielectric layer having a different second coefficient of thermal expansion, and at least one dummy element configured to lower stress at an interface between the superconducting element and the dielectric layer when operating in a cryogenic environment. Preferably, the superconducting element is a Nb wire (110, 120, 130, 150) on a SiO2 layer (104), and the dummy elements are protruding nubs (112, 114, 116, 122, 124), passive vias (134, 136) below, or surface features (152) on top of the wire.