Photosensitive Polyimide Resin for Flat, Chemical-Resistant RDLs

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing photosensitive resin compositions used in semiconductor devices lack sufficient flatness and chemical resistance, particularly in applications requiring miniaturized and laminated re-distribution wiring, which hinders the advancement of inter-chip signal speed and reliability.

Innovation Solution

A photosensitive resin composition comprising a polyimide with a polymerizable group and a weight-average molecular weight of 5,000 to 30,000, a polymerizable compound, and a photopolymerization initiator, designed to minimize mass reduction and shrinkage during curing, ensuring excellent flatness and chemical resistance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If existing photosensitive resin compositions are used, then manufacturing adaptability is maintained, but flatness and chemical resistance are insufficient

Engineering Contradiction:

Improvechemical resistanceVSAvoidflatness

Core Design Contradiction:

ReliabilityVSManufacturing precision

Solution Approach 1:

The patent changes the molecular weight parameter of the polyimide resin to a specific range (5,000 to 30,000) and controls the polymerizable group content (0.1 to 5 mmol/g) to optimize both flatness and chemical resistance. This parameter optimization resolves the contradiction by finding the sweet spot where both requirements are satisfied simultaneously.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent creates a composite resin system combining polyimide with specific polymerizable groups (vinyl, vinyl ether, or allyl groups) and crosslinking agents. This composite approach enhances both flatness through controlled shrinkage and chemical resistance through the crosslinked network structure, resolving the technical contradiction.

Inventive Principle:

Principle #40Composite materials

2Speed

If miniaturization and lamination of re-distribution wiring are pursued, then inter-chip signal speed increases, but requirements for flatness and chemical resistance become more stringent

Engineering Contradiction:

Improveinter-chip signal speedVSAvoidflatness

Core Design Contradiction:

SpeedVSManufacturing precision

Solution Approach 1:

The patent optimizes the polyimide molecular weight and polymerizable group content parameters to achieve minimal shrinkage during curing, ensuring flatness is maintained even as wiring dimensions are reduced and layers are added, thereby supporting higher signal speeds without compromising manufacturing precision.

Inventive Principle:

Principle #35Parameter changes

3Ease of manufacture

If polyimide with lower molecular weight is used, then viscosity decreases and coating becomes easier, but chemical resistance and mechanical strength deteriorate

Engineering Contradiction:

Improvecoating processabilityVSAvoidchemical resistance

Core Design Contradiction:

Ease of manufactureVSReliability

Solution Approach 1:

The patent identifies an optimal molecular weight range (5,000 to 30,000) for polyimide that balances viscosity for coating processability with chemical resistance. This parameter optimization resolves the contradiction by avoiding both extremes - not too high viscosity for easy coating, not too low molecular weight for adequate resistance.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent enhances the chemical resistance of the optimized polyimide by incorporating polymerizable groups and crosslinking agents, creating a composite material system that maintains good coating properties while achieving the required chemical resistance for semiconductor applications.

Inventive Principle:

Principle #40Composite materials

4Reliability

If crosslinking density is increased to improve chemical resistance, then durability increases, but shrinkage and stress during curing increase

Engineering Contradiction:

Improvechemical resistanceVSAvoidcuring stress

Core Design Contradiction:

ReliabilityVSStress or pressure

Solution Approach 1:

The patent controls the polymerizable group content within a specific range (0.1 to 5 mmol/g) to achieve moderate crosslinking density. This optimized parameter set provides sufficient chemical resistance while limiting excessive shrinkage and curing stress, resolving the technical contradiction between durability and stress.

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 composition achieves cured substances with minimal shrinkage and high chemical resistance, enabling improved flatness and durability in semiconductor applications, particularly in insulating films and re-distribution layers.

Implementation Method 1

a photopolymerization initiator

Methodology Applied

Scientific EffectPhotopolymerization: Photopolymerisation

Data Source

PatentUS20260003274A1Photosensitive resin composition, cured substance, laminate, manufacturing method for cured substance, manufacturing method for laminate, manufacturing method for semiconductor device, and semiconductor device

Publication Date: 2026.01.01 FUJIFILM CORP

AI summary

There are provided a photosensitive resin composition including a resin which is a polyimide having a polymerizable group and a weight-average molecular weight of 5,000 or more and less than 30,000, a polymerizable compound, and a photopolymerization initiator; a cured substance obtained by curing the resin composition; a laminate including the cured substance; a manufacturing method for the cured substance; a manufacturing method for a laminate; a manufacturing method for a semiconductor device, including the manufacturing method for the cured substance; and a semiconductor device including the cured substance.