Sinter Bonding Sheet Surface Roughness for Stable Layer Transfer

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing sinter bonding sheets experience issues with poor transfer properties and substrate layer separation during the pickup process, leading to wrinkles and inadequate bonding between the sinter bonding layer and substrate layer.

Innovation Solution

A sinter bonding sheet with a sinter bonding layer containing conductive metal particles and an organic binder, where the surface roughness of the bonding layer is controlled between 10.5 nm and 90.0 nm, and a substrate layer is applied under specific pressing conditions to ensure good transfer properties and prevent substrate layer separation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the surface roughness of the sinter bonding layer is increased to improve transfer properties, then the bonding strength to semiconductor chips improves, but the substrate layer separation tendency increases

Engineering Contradiction:
Improvetransfer propertiesVSAvoidsubstrate layer adhesion
Core Design Contradiction:
ReliabilityVSStability of the object's composition

Solution Approach 1:

The patent applies parameter changes by precisely controlling the surface roughness Ra of the sinter bonding layer within the range of 10.5 nm to 90.0 nm. This specific parameter range optimizes the balance between transfer properties and substrate layer adhesion, resolving the contradiction between these two requirements.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent applies local quality by creating a specific surface roughness profile on the sinter bonding layer that is optimized for its intended function. The controlled roughness provides enhanced bonding characteristics at the interface with semiconductor chips while maintaining overall layer stability.

Inventive Principle:
Principle #3Local quality

2Strength

If the pressing force is increased to improve bonding between layers, then the bonding strength improves, but the substrate layer separation and wrinkling increases

Engineering Contradiction:
Improvebonding strengthVSAvoidsubstrate layer separation and wrinkling
Core Design Contradiction:
StrengthVSObject-generated harmful factors

Solution Approach 1:

The patent applies parameter changes by optimizing the pressing force applied during the lamination process. By controlling the pressing force within appropriate limits and combining it with the controlled surface roughness, the patent achieves strong bonding without causing substrate layer separation or wrinkling.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent applies beforehand cushioning by pre-controlling the surface roughness of the sinter bonding layer before lamination. This pre-prepared surface condition cushiones against the harmful effects of excessive pressing force, allowing strong bonding to be achieved without substrate layer separation or wrinkling.

Inventive Principle:
Principle #11Beforehand cushioning (Prior cushioning)

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 controlled surface roughness and pressing conditions enhance the transfer properties of the sinter bonding layer to semiconductor chips while minimizing substrate layer separation, resulting in reliable bonding and improved semiconductor device production.

Implementation Method 1

The intermediate product of the semiconductor device is subjected to sintering treatment in which the intermediate product of the semiconductor device is heated at a temperature at which sinterable particles in the sinter bonding layer can be sintered to each other, to thereby at least partially eliminate the organic binder from the sinter bonding layer while sintering the sinterable particles to each other.

Methodology Applied
Scientific EffectSintering: Sintering

Data Source

PatentEP4691668A1Sinter bonding sheet, and method for producing sinter bonding sheet
Publication Date: 2026.02.11 NITTO DENKO CORP
  • EP4691668A1 patent drawingFigure 1A~1B
  • EP4691668A1 patent drawingFigure 2A~2B
  • EP4691668A1 patent drawingFigure 2C(I)~2C(III)

AI summary

Provided is, for example, a sinter bonding sheet including: a sinter bonding layer including sinterable particles containing a conductive metal, and an organic binder; and a substrate layer layered on at least one surface of the sinter bonding layer, in which the at least one surface of the sinter bonding layer on which the substrate layer is layered has a surface roughness Ra of 10.5 nm or more and 90.0 nm or less.