Chromium Oxide Substrate for Superconductive Wire Delamination

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The challenge in manufacturing oxide superconductive wires is the delamination of layers during film deposition and heat treatment, which occurs due to interdiffusion and interfacial reactions, especially when film thickness is reduced, leading to poor superconductive characteristics and manufacturing inefficiencies.

Innovation Solution

A substrate with a metal substrate and intermediate layer having an arithmetic average roughness of not more than 50 nm, where an oxide layer containing chromium is formed to prevent delamination, either directly on the substrate or as an intermediate layer, enhancing the substrate's oxidation resistance and reducing interfacial stress.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If the thickness of layers is reduced to improve manufacturing speed, then productivity increases, but delamination between layers occurs due to interdiffusion and interfacial reactions

Engineering Contradiction:
Improvemanufacturing speedVSAvoidlayer adhesion
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

A chromium-containing oxide intermediate layer is introduced between the metal substrate and the superconductive film. This intermediate layer acts as a barrier that prevents interdiffusion and interfacial reactions between the metal substrate and the superconductive film, thereby preventing delamination even when layer thickness is reduced for faster manufacturing.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent employs a composite structure consisting of a metal substrate, a chromium-containing oxide intermediate layer, and a superconductive film. This composite structure combines the advantages of each material: the metal substrate provides flexibility, the chromium oxide layer provides diffusion barrier and adhesion properties, and the superconductive film provides the desired superconductive characteristics.

Inventive Principle:
Principle #40Composite materials

2Reliability

If a monocryatalline substrate is used to achieve excellent current characteristics, then superconductive performance improves, but the substrate cannot be bent or worked into elongated strips

Engineering Contradiction:
Improvecurrent characteristicsVSAvoidflexibility
Core Design Contradiction:
ReliabilityVSEase of operation

Solution Approach 1:

The patent applies local quality by introducing a chromium-containing oxide intermediate layer specifically at the interface between the metal substrate and the superconductive film. This localized treatment ensures that the metal substrate can be worked into flexible strips while the critical interface regions maintain strong adhesion and prevent delamination, enabling both flexibility and good current characteristics.

Inventive Principle:
Principle #3Local quality

3Reliability

If multiple intermediate layers are deposited to prevent delamination, then layer adhesion improves, but manufacturing complexity and time increase

Engineering Contradiction:
Improvelayer adhesionVSAvoidmanufacturing process complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent extracts the essential function of preventing delamination by focusing on a single chromium-containing oxide intermediate layer that provides both diffusion barrier and adhesion properties. This simplifies the manufacturing process compared to using multiple intermediate layers, while still effectively preventing interdiffusion and interfacial reactions between the metal substrate and the superconductive film.

Inventive Principle:
Principle #2Taking out (Extraction)

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

This approach prevents delamination, maintains excellent superconductive characteristics, enhances manufacturing speed, and reduces costs by ensuring reliable and flexible oxide superconductive wire production.

Implementation Method 1

an oxide layer containing chromium is formed to prevent delamination, either directly on the substrate or as an intermediate layer

Methodology Applied
Scientific EffectDiffusion barrier: Diffusion Barrier

Implementation Method 2

the metal substrate and independently the intermediate layer have an arithmetic average roughness Ra of not more than 50 nm

Methodology Applied
Scientific EffectSurface roughness control:

Data Source

PatentEP2360701B8Substrate for super-conductive film formation, super-conductive wire material, and method for producing the same
Publication Date: 2016.08.24 FURUKAWA ELECTRIC CO LTD

AI summary

Provided is a substrate for superconductive film formation, which includes a metal substrate, and an oxide layer formed directly on the metal substrate, containing chromium oxide as a major component and having a thickness of 10-300 nm and an arithmetic average roughness Ra of not more than 50 nm. A method of manufacturing a substrate for superconductive film formation, which includes forming an oxide layer directly on a metal substrate, the oxide layer containing chromium oxide as a major component and having a thickness of 10-300 nm and an arithmetic average roughness Ra of not more than 50 nm.