Heat-Resistant Adhesive Sheet for Semiconductor Wafer Inspection

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

In semiconductor equipment manufacturing, semiconductor chips malfunctioning at high temperatures are not distinguished until after packaging, leading to increased packaging costs and issues with adhesive sheet deformation causing inspection delays and failures during high-temperature performance inspection.

Innovation Solution

A heat-resistant adhesive sheet with a substrate that shrinks by 1.0% to 5.0% at 120°C and an adhesive layer composed of (meth)acrylate copolymer, photopolymerizable compound, polyfunctional isocyanate curing agent, and photopolymerization initiator, which restricts deformation and reduces adhesion strength upon heating, allowing for effective semiconductor wafer inspection before packaging.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If performance inspection is carried out at high temperatures after packaging, then faulty chips can be identified, but packaging costs increase and packaging time is extended

Engineering Contradiction:
Improvechip quality identificationVSAvoidpackaging time
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The adhesive sheet is designed to maintain controlled adhesion strength during high-temperature inspection, allowing inspection to be performed before packaging. This preliminary inspection identifies faulty chips early, preventing them from entering the packaging process and reducing overall packaging time and costs.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The adhesive composition is specifically formulated with (meth)acrylate copolymer, photopolymerizable compound, and curing agents in controlled ratios. The adhesive strength is dynamically adjusted through UV irradiation duration and intensity, allowing the sheet to maintain appropriate adhesion during high-temperature inspection while enabling easy chip pickup afterward.

Inventive Principle:
Principle #35Parameter changes

2Loss of time

If performance inspection is carried out at high temperatures before packaging, then packaging costs are reduced, but adhesive sheet deformation occurs causing inspection failures

Engineering Contradiction:
Improvepackaging timeVSAvoidinspection success rate
Core Design Contradiction:
Loss of timeVSReliability

Solution Approach 1:

The adhesive composition parameters are precisely controlled with (meth)acrylate copolymer at 100 parts, photopolymerizable compound at 5-200 parts, and polyfunctional isocyanate curing agent at 0.5-20 parts. This specific parameter range maintains adhesive stability at high temperatures while preventing sheet deformation during inspection.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The adhesive sheet uses a composite formulation combining (meth)acrylate copolymer with photopolymerizable compound and polyfunctional isocyanate curing agent. This composite material structure provides thermal stability during high-temperature inspection while maintaining appropriate adhesion characteristics, preventing sheet deformation and inspection failures.

Inventive Principle:
Principle #40Composite materials

3Ease of operation

If adhesive strength is reduced for easy chip pickup, then chip removal is facilitated, but chip retention during dicing and drying becomes insufficient

Engineering Contradiction:
Improvechip pickup easeVSAvoidchip retention strength
Core Design Contradiction:
Ease of operationVSStrength

Solution Approach 1:

The adhesive strength is dynamically controlled through UV irradiation. Before irradiation, the adhesive maintains high strength for chip retention during dicing and drying. After UV irradiation, the photopolymerizable compound cures and reduces adhesion strength, facilitating easy chip pickup. This dynamic adjustment resolves the contradiction between retention and removal.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The adhesive composition parameters are precisely controlled with (meth)acrylate copolymer at 100 parts, photopolymerizable compound at 5-200 parts, and polyfunctional isocyanate curing agent at 0.5-20 parts. This specific parameter range enables the adhesive to maintain strong bonding during processing while allowing controlled strength reduction for easy pickup after UV treatment.

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

Enables inspection of semiconductor wafers under heating conditions, reducing packaging costs by identifying faulty chips before packaging and preventing adhesive sheet deformation and pickup failures.

Implementation Method 1

the substrate has a thermal shrinkage when heated at 120° C. for 15 minutes from 1.0% to 5.0%

Methodology Applied
Scientific EffectThermal shrinkage: Thermal Contraction

Implementation Method 2

an adhesive layer that develops polymerization curing reaction by ultraviolet rays and the like

Methodology Applied
Scientific EffectPhotopolymerization: Photopolymerisation

Data Source

PatentUS9676968B1Heat-resistant adhesive sheet for semiconductor inspection and semiconductor inspection method
Publication Date: 2017.06.13 DENKA CO LTD

AI summary

A heat resistant adhesive sheet is provided that does not easily develop deformation of an adhesive sheet due to heating. Such an adhesive sheet made by laminating an adhesive layer to a substrate is provided, characterized in that the substrate is heat shrinkable and the adhesive layer contains a (meth)acrylate copolymer, a photopolymerizable compound, a polyfunctional isocyanate curing agent, and a photopolymerization initiator and does not substantially contain a tackifying resin. This adhesive sheet is not deformed even when heated. Since the adhesive does not substantially contain a tackifying resin, softening of the adhesive layer does not occur even when the sheet is heated.