Method of making a nanostructure

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current methods for producing nanostructures on non-conductive substrates, such as (co)polymeric films, face challenges including charging effects that prevent pattern transfer of high aspect ratio features below 200 micrometers and require expensive, complicated batch processes under extreme vacuum conditions, limiting their commercial viability for continuous production.

Innovation Solution

A method involving a plasma process that simultaneously etches and deposits a layer on the substrate using a mixture of gaseous species, allowing for the creation of durable, high aspect ratio nanostructures on (co)polymeric substrates in a single stage, continuous operation at moderate vacuum conditions, suitable for roll-to-roll production.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If plasma etching is used to produce nanostructures on non-conductive substrates, then nanostructure formation is achieved, but charging effects prevent pattern transfer of high aspect ratio features below 200 micrometers

Engineering Contradiction:
Improvepattern transfer precisionVSAvoidcharging effects
Core Design Contradiction:
Manufacturing precisionVSObject-affected harmful factors

Solution Approach 1:

A conductive coating layer is applied as an intermediary between the plasma etching process and the non-conductive substrate. This conductive layer acts as a mediator that allows plasma ions to reach the substrate surface without causing charging effects, enabling precise pattern transfer of high aspect ratio features while eliminating the harmful charging phenomenon that would otherwise occur on non-conductive materials

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The electrical conductivity parameter of the substrate surface is changed by applying a conductive coating layer. This parameter change transforms the substrate from electrically insulating to electrically conductive, allowing the plasma etching process to proceed without charge accumulation, thereby enabling precise pattern transfer of sub-200 micrometer features

Inventive Principle:
Principle #35Parameter changes

2Manufacturing precision

If batch processes are used to create sub-wavelength surface structures, then nanostructures can be produced, but the process becomes complicated and expensive

Engineering Contradiction:
Improvesub-wavelength structure precisionVSAvoidprocess complexity
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The process transitions from discrete batch operations to a continuous plasma etching process. The substrate can be continuously fed through the plasma reactor, allowing uninterrupted production of sub-wavelength structures. This continuous action eliminates the need for repeated loading/unloading cycles and multiple processing steps, thereby simplifying the overall process while maintaining nanoscale precision

Inventive Principle:
Principle #20Continuity of useful action

Solution Approach 2:

Multiple process functions are merged into a single plasma treatment step. The conductive coating application and the pattern transfer etching are combined into one integrated process sequence, eliminating the need for separate batch processing steps. This merging reduces process complexity while maintaining the ability to produce precise sub-wavelength structures

Inventive Principle:
Principle #5Merging (Combining)

3Manufacturing precision

If batch processes operate under extreme vacuum conditions, then nanostructures can be formed, but productivity and commercial viability are limited

Engineering Contradiction:
Improvenanostructure formation precisionVSAvoidproduction rate
Core Design Contradiction:
Manufacturing precisionVSProductivity

Solution Approach 1:

The vacuum pressure parameter is changed from extreme vacuum conditions to moderate vacuum conditions. This parameter change allows the plasma process to operate at higher pressures where mean free path is sufficient for anisotropic etching while enabling faster substrate throughput. The conductive coating enables this pressure increase without sacrificing pattern transfer precision, thereby increasing productivity and commercial viability

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The process enables continuous operation at moderate vacuum conditions rather than requiring intermittent batch processing under extreme vacuum. substrates can be continuously processed through the plasma reactor without needing to maintain ultra-high vacuum throughout the entire production line, significantly increasing production rate while maintaining nanostructure formation precision

Inventive Principle:
Principle #20Continuity of useful action

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 enables the production of nanostructured surfaces with reduced reflectance and enhanced adhesion, providing durable and scratch-resistant features on large areas, including fluoropolymers, which are notoriously difficult to adhere to, while maintaining cost-effectiveness and simplicity.

Implementation Method 1

forming the gaseous mixture into a plasma, and exposing a surface of the substrate to the plasma

Methodology Applied
Scientific EffectPlasma: Plasma

Implementation Method 2

etching portions of the major surface not protected by the masking layer to form a nanostructure on the substrate by reactive ion etching

Methodology Applied
Scientific EffectReactive ion etching:

Implementation Method 3

applying a thin, random, discontinuous masking layer to a major surface of the substrate by plasma chemical vapor deposition

Methodology Applied
Scientific EffectPlasma chemical vapor deposition: Plasma Enhanced Chemical Vapour Deposition

Data Source

PatentEP3024777B1Method of making a nanostructure
Publication Date: 2024.05.15 3M INNOVATIVE PROPERTIES CO
  • EP3024777B1 patent drawingFigure 1a~1b
  • EP3024777B1 patent drawingFigure 2
  • EP3024777B1 patent drawingFigure 3

AI summary

A method of making a nanostructure and nanostructured articles by depositing a layer to a major surface of a substrate by plasma chemical vapor deposition from a gaseous mixture while substantially simultaneously etching the surface with a reactive species. The method includes providing a substrate; mixing a first gaseous species capable of depositing a layer onto the substrate when formed into a plasma, with a second gaseous species capable of etching the substrate when formed into a plasma, thereby forming a gaseous mixture; forming the gaseous mixture into a plasma; and exposing a surface of the substrate to the plasma, wherein the surface is etched and a layer is deposited on at least a portion of the etched surface substantially simultaneously, thereby forming the nanostructure. The substrate can be a (co)polymeric material, an inorganic material, an alloy, a solid solution, or a combination thereof. The deposited layer can include the reaction product of plasma chemical vapor deposition using a reactant gas comprising a compound selected from the group consisting of organosilicon compounds, metal alkyl compounds, metal isopropoxide compounds, metal acetylacetonate compounds, metal halide compounds, and combinations thereof. Nanostructures of high aspect ratio and optionally with random dimensions in at least one dimension and preferably in three orthogonal dimensions can be prepared.