Ceramic Cooler Semiconductor Device Thermal Stress Management

Solution Overview

Problem

As miniaturization and high-power capabilities in power semiconductor devices advance, efficient heat radiation of semiconductor chips becomes crucial, but existing solutions face challenges in maintaining thermal efficiency and reliability due to differences in thermal expansion coefficients between materials, leading to issues like warpage, cracking, and peeling.

Innovation Solution

A semiconductor device design featuring a ceramic cooler with conductive-pattern layers and a seal member including resin and filler, which covers the semiconductor chip and side faces, along with optional buffer films to manage thermal stress and enhance adhesion, thereby reducing thermal resistance and improving cooling efficiency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Temperature

If a ceramic cooler is used to improve heat dissipation, then thermal efficiency is improved, but warpage and peeling occur due to thermal expansion differences

Engineering Contradiction:

Improveheat dissipation efficiencyVSAvoidstructural stability

Core Design Contradiction:

TemperatureVSReliability

Solution Approach 1:

A seal member comprising a resin matrix and inorganic filler particles is introduced as an intermediary material between the ceramic cooler and the semiconductor chip. This seal member has thermal expansion characteristics that bridge the gap between the ceramic material and other components, absorbing thermal stress and preventing warpage and peeling while maintaining effective heat dissipation pathways.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The seal member is constructed as a composite material system consisting of a resin matrix reinforced with inorganic filler particles. This composite structure combines the low thermal expansion properties of the inorganic filler with the adhesive and stress-absorbing characteristics of the resin matrix, creating a material that can accommodate thermal expansion differences while maintaining structural integrity and thermal conductivity.

Inventive Principle:

Principle #40Composite materials

2Power

If miniaturization and high-power capability are advanced, then power density is improved, but thermal management becomes more difficult

Engineering Contradiction:

Improvepower densityVSAvoidheat dissipation difficulty

Core Design Contradiction:

PowerVSTemperature

Solution Approach 1:

The cooler structure is designed with locally optimized thermal conduction pathways, including protruding portions that directly contact the semiconductor chip to create low-resistance thermal paths. The seal member is strategically positioned at critical interfaces where thermal stress concentrates, providing localized stress relief while maintaining overall thermal management efficiency for high-power density applications.

Inventive Principle:

Principle #3Local quality

3Temperature

If different materials are used to improve thermal efficiency, then heat dissipation is improved, but adhesion between materials deteriorates

Engineering Contradiction:

Improvethermal conductivityVSAvoidadhesion strength

Core Design Contradiction:

TemperatureVSStrength

Solution Approach 1:

The seal member is constructed as a composite material system consisting of a resin matrix reinforced with inorganic filler particles. This composite structure combines the low thermal expansion properties of the inorganic filler with the adhesive and stress-absorbing characteristics of the resin matrix, creating a material that can accommodate thermal expansion differences while maintaining structural integrity and thermal conductivity.

Inventive Principle:

Principle #40Composite materials

Solution Approach 2:

A seal member comprising a resin matrix and inorganic filler particles is introduced as an intermediary material between the ceramic cooler and the semiconductor chip. This seal member has thermal expansion characteristics that bridge the gap between the ceramic material and other components, absorbing thermal stress and preventing warpage and peeling while maintaining effective heat dissipation pathways.

Inventive Principle:

Principle #24Intermediary (Mediator)

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 solution effectively suppresses warpage and peeling, maintains thermal efficiency, and enhances the reliability of the semiconductor device by managing thermal stress and improving adhesion between materials, ensuring effective heat dissipation and prolonged device lifespan.

Implementation Method 1

differences in thermal expansion coefficients between materials, leading to issues like warpage, cracking, and peeling

Methodology Applied

Scientific EffectThermal expansion: Thermal Expansion

Implementation Method 2

efficient heat radiation of semiconductor chips becomes crucial

Methodology Applied

Scientific EffectThermal conduction: Conduction (thermal)

Data Source

PatentUS11201121B2Semiconductor device

Publication Date: 2021.12.14 FUJI ELECTRIC CO LTD

AI summary

A semiconductor device encompasses a cooler made of ceramics, having a first main face and a second main face, being parallel and opposite to the first main face, defined by two opposite side faces perpendicular to the first and second main faces, a plurality of conductive-pattern layers delineated on the first main face, a semiconductor chip mounted on the first main face via one of the plurality of conductive-pattern layers, and a seal member configured to seal the semiconductor chip.