Embossed Film Mask Structure for Uniform Roll-to-Roll Patterning

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing film mask-based roll-to-roll photolithography technologies face issues with adhesive force, resolution, and mechanical defects leading to mura and non-uniform thickness during patterning, particularly in roll-to-roll exposure processes using dry film resist and mechanical reinforcement methods.

Innovation Solution

A film mask with a transparent substrate, darkened light-shielding pattern layer, and embossed pattern part, featuring varying metal layer thicknesses or direct contact regions, along with additional layers for attachment and release force enhancement, to maintain uniform thickness and reduce mura during roll-to-roll patterning.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If a lamination process is introduced to maximize adhesive force of film mask to substrate, then adhesive force is improved, but machining tolerance and deformation cause difficulty in maintaining exact tolerance

Engineering Contradiction:
Improveadhesive forceVSAvoidpatterning tolerance
Core Design Contradiction:
StrengthVSManufacturing precision

Solution Approach 1:

The film mask is pre-laminated to the substrate before the actual patterning process. This preliminary lamination ensures that the film mask is firmly attached and positioned correctly on the substrate, preventing deviation during subsequent processing steps while maintaining patterning tolerance through controlled lamination parameters

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The lamination process parameters such as pressure, temperature, and speed are precisely controlled and optimized to achieve the right balance between adhesive force and patterning tolerance. By adjusting these parameters, the system maximizes attachment strength while minimizing deformation and maintaining exact tolerance requirements

Inventive Principle:
Principle #35Parameter changes

2Strength

If dry film resist is warmed to near 100°C for lamination, then adhesive force is improved, but resolution capability deteriorates due to inherent DFR resolution problems

Engineering Contradiction:
Improveadhesive forceVSAvoidpattern resolution
Core Design Contradiction:
StrengthVSManufacturing precision

Solution Approach 1:

The warming temperature of the dry film resist is precisely controlled to near 100°C during lamination. This temperature optimization provides sufficient adhesive force for proper attachment while being carefully managed to avoid excessive thermal effects that would degrade the resolution capability of the DFR material

Inventive Principle:
Principle #35Parameter changes

3Stability of the object's composition

If mechanical reinforcement is conducted using crown roll or edge polishing, then roll deformation is reduced, but local deformation still occurs due to fluid characteristics of photosensitive resin

Engineering Contradiction:
Improveroll shape stabilityVSAvoidpattern uniformity
Core Design Contradiction:
Stability of the object's compositionVSManufacturing precision

Solution Approach 1:

The film mask incorporates regions with different metal layer thicknesses or direct contact regions between the transparent substrate and darkened light-shielding pattern layer. This creates local variations in mechanical properties and contact characteristics that compensate for local deformations caused by the fluid characteristics of the photosensitive resin, ensuring uniform pattern formation across the entire substrate

Inventive Principle:
Principle #3Local quality

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 film mask effectively reduces mura and maintains uniform thickness despite mechanical defects, ensuring high-resolution patterns with consistent thickness across the roll-to-roll process.

Implementation Method 1

a metal layer provided between the transparent substrate and the darkened light-shielding pattern layer is provided, wherein the film mask includes two or more regions of the metal layer having different thicknesses from each other or two or more regions of the darkened light-shielding pattern layer having different thicknesses from each other

Methodology Applied
Scientific EffectMechanical deformation compensation:

Implementation Method 2

an embossed pattern part provided on a surface of the transparent substrate, on which the darkened light-shielding pattern layer is provided

Methodology Applied
Scientific EffectMechanical support:

Implementation Method 3

a darkened light-shielding pattern layer provided on the transparent substrate

Methodology Applied
Scientific EffectLight absorption: Absorption (EM radiation)

Implementation Method 4

a transparent substrate; a darkened light-shielding pattern layer provided on the transparent substrate

Methodology Applied
Scientific EffectLight transmission:

Implementation Method 5

additional layers for attachment and release force enhancement

Methodology Applied
Scientific EffectAdhesion: Adhesive

Data Source

PatentEP3410214B1Film mask, method for manufacturing same, and method for forming pattern using film mask and pattern formed thereby
Publication Date: 2025.07.30 LG CHEM LTD
  • EP3410214B1 patent drawingFigure 1
  • EP3410214B1 patent drawingFigure 2~3
  • EP3410214B1 patent drawingFigure 4(a)~4(c)

AI summary

The present application relates to a film mask comprising: a transparent substrate; a darkened light-shielding pattern layer provided on the transparent substrate; and an embossed pattern part provided on a surface of the transparent substrate, which is provided with the darkened light-shielding pattern layer, a method for manufacturing the same, a method for forming a pattern by using the same, and a pattern formed by using the same.