Adhesion Layer Composition for Defect-Free Photo-Nanoimprinting

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

In photo-nanoimprinting processes, the adhesion between the photocurable composition and the substrate is often insufficient, leading to defects such as pattern separation during the mold-releasing step, despite the use of adhesion layers containing reactive functional groups bound to heterocyclic rings with nitrogen and unsaturated bonds.

Innovation Solution

An adhesion layer composition is developed with compounds having multiple functional groups directly bound to hydrocarbons or aromatic hydrocarbons, including hydroxy, carboxy, thiol, amino, and epoxy groups, which form chemical bonds with the substrate and photocurable composition, enhancing adhesion without light absorption issues.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If an adhesion layer containing a compound with a reactive functional group bound to a heterocyclic ring containing nitrogen and an unsaturated bond is used, then the adhesion between photocurable composition and substrate is enhanced, but light absorption occurs leading to insufficient adhesion and pattern separation defects

Engineering Contradiction:
Improveadhesion strengthVSAvoidlight absorption
Core Design Contradiction:
StrengthVSObject-affected harmful factors

Solution Approach 1:

The patent changes the chemical structure parameters of the adhesion layer compound by replacing the heterocyclic ring containing nitrogen and unsaturated bond with a heterocyclic ring containing sulfur (such as thiazole, thiazolidine, or dithiazole rings). This structural parameter change eliminates light absorption while maintaining the reactive functional groups (thiol, amino, hydroxy, carboxy, or epoxy groups) necessary for strong adhesion between the photocurable composition and substrate.

Inventive Principle:
Principle #35Parameter changes

2Ease of manufacture

If conventional photocurable composition is used without adhesion layer, then the process is simple, but adhesion is insufficient causing pattern separation

Engineering Contradiction:
Improveprocess simplicityVSAvoidadhesion strength
Core Design Contradiction:
Ease of manufactureVSStrength

Solution Approach 1:

The patent introduces a heterocyclic sulfur compound as an intermediary adhesion layer between the substrate and the photocurable composition. This intermediary layer contains reactive functional groups that form chemical bonds with both the substrate and the photocurable composition, mediating the adhesion interface and preventing pattern separation while maintaining process simplicity.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Reliability

If adhesion layer with heterocyclic nitrogen compound is used, then chemical bonding capability is improved, but light absorption reduces adhesion effectiveness

Engineering Contradiction:
Improveadhesion reliabilityVSAvoidlight energy absorption
Core Design Contradiction:
ReliabilityVSUse of energy by moving object

Solution Approach 1:

The patent changes the elemental composition parameter of the heterocyclic ring from nitrogen to sulfur, creating compounds such as thiazole, thiazolidine, or dithiazole rings. This parameter change eliminates light energy absorption in the UV range while preserving the chemical bonding capability through reactive functional groups, thereby improving adhesion reliability without compromising to light energy.

Inventive Principle:
Principle #35Parameter changes

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 proposed adhesion layer composition ensures strong adhesion between the photocurable composition and the substrate, preventing pattern separation and enabling the formation of high-quality optical components, circuit boards, and electronic apparatuses with reduced defects.

Implementation Method 1

The adhesion layer composition contains a compound (A) having at least two binding functional groups... capable of being bound to the substrate and capable of being bound to the photocurable composition

Methodology Applied
Scientific EffectChemical bonding: Chemical Bonding

Implementation Method 2

the resist is cured by being irradiated with light (irradiation step)

Methodology Applied
Scientific EffectPhotopolymerization: Photopolymerisation

Data Source

PatentEP3158578B1Adhesion layer composition, method for forming film by nanoimprinting, methods for manufacturing optical component, circuit board and electronic apparatus
Publication Date: 2024.01.10 CANON KK
  • EP3158578B1 patent drawingFigure 1A~1G
  • EP3158578B1 patent drawingFigure 1H

AI summary

In nanoimprinting processes, photo-cured products often separate from the substrate and stick to the mold due to insufficient adhesion between the photo-cured product and the substrate. This causes a defect of pattern separation. An adhesion layer composition used for forming an adhesion layer between a substrate and a photocurable composition includes a compound (A) having at least two functional groups, and a solvent (B). The functional groups include at least one functional group capable of being bound to the substrate, selected from the group consisting of hydroxy, carboxy, thiol, amino, epoxy, and (blocked) isocyanate, and at least one hydrogen donating group as a functional group capable of being bound to the photocurable composition.