Conductive Ceramic Mount for High-Temp Semiconductor Stress Reduction

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing semiconductor arrangements face mechanical stresses due to thermal expansion differences between metal layers and ceramic mounts, limiting their use to high temperatures, especially above 250°C, and are prone to failure under environmental stressors like vibration and corrosive conditions.

Innovation Solution

A semiconductor arrangement using a ceramic mount that is electrically conductive, particularly metallically conductive, to eliminate the need for thick metal layers, allowing direct voltage and current supply and reducing thermal expansion stresses, with the ceramic mount providing excellent heat dissipation and mechanical stability by matching thermal expansion coefficients with the semiconductor component.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If thick metal layers are used to bond the semiconductor component to the ceramic mount, then mechanical bonding strength is improved, but mechanical stresses from thermal expansion differences increase

Engineering Contradiction:

Improvebonding strengthVSAvoidmechanical stress

Core Design Contradiction:

StrengthVSStress or pressure

Solution Approach 1:

The patent changes the material parameter of the mount from conventional ceramic to electrically conductive ceramic, which has different thermal expansion characteristics that better match the metal layer, thereby reducing thermal stress while maintaining bonding strength

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent uses composite material structure with electrically conductive ceramic that combines the insulating properties of ceramic with electrical conductivity, creating a material that simultaneously reduces thermal stress and provides electrical connection

Inventive Principle:

Principle #40Composite materials

2Reliability

If conventional ceramic mounts are used, then electrical insulation is provided, but electrical connection complexity increases

Engineering Contradiction:

Improveelectrical insulationVSAvoidconnection complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent makes the mount serve multiple functions simultaneously: mechanical support, thermal management, and electrical connection through the electrically conductive ceramic material, eliminating the need for separate connection structures

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The patent merges the electrical connection function into the mount structure itself by using electrically conductive ceramic, combining what were previously separate components (mount and electrical connector) into a single integrated element

Inventive Principle:

Principle #5Merging (Combining)

3Stability of the object's composition

If thick metal layers are used for bonding, then mechanical stability is improved, but heat dissipation efficiency decreases

Engineering Contradiction:

Improvemechanical stabilityVSAvoidheat dissipation efficiency

Core Design Contradiction:

Stability of the object's compositionVSLoss of energy

Solution Approach 1:

The patent changes the material composition from thick metal layers to thin metal layers on electrically conductive ceramic, altering the thermal and mechanical parameters to achieve both stability and efficient heat dissipation

Inventive Principle:

Principle #35Parameter changes

4Temperature

If the semiconductor arrangement is designed for high temperature operation, then temperature resistance is improved, but mechanical stress from thermal expansion increases

Engineering Contradiction:

Improveoperating temperatureVSAvoidthermal expansion stress

Core Design Contradiction:

TemperatureVSStress or pressure

Solution Approach 1:

The patent selects electrically conductive ceramic material with specific thermal expansion parameters that match both the semiconductor component and metal layers, enabling high-temperature operation while minimizing differential thermal expansion stresses

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 reliable operation at high temperatures (above 400°C) with reduced mechanical stresses and improved heat dissipation, suitable for applications like motor vehicle generators using wide band gap semiconductor materials like SiC.

Implementation Method 1

forming the mount for the semiconductor component, at least in places, from a ceramic which is electrically conductive, in particular metallically conductive

Methodology Applied

Scientific EffectElectrical conduction: Conduction (electrical)

Implementation Method 2

a mount which is formed at least in places from electrically conductive ceramic material is distinguished by a very high thermal conductivity which ensures good heat dissipation

Methodology Applied

Scientific EffectThermal conduction: Conduction (thermal)

Implementation Method 3

the comparatively thick metal layer has a different coefficient of thermal expansion from the semiconductor material of the semiconductor component and the mount ceramic

Methodology Applied

Scientific EffectThermal expansion: Thermal Expansion

Data Source

PatentUS8946885B2Semiconductor arrangement and method for producing a semiconductor arrangement

Publication Date: 2015.02.03 ROBERT BOSCH GMBH

AI summary

A semiconductor arrangement includes a ceramic mount and at least one semiconductor component fixed-to the ceramic mount. The ceramic mount includes a first section, and the first section is electrically conductive.