Thick-First Conductor Layer Substrate for Heat Dissipation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current electrical circuits face challenges in heat dissipation due to the thin copper cladding on insulating metal substrates, leading to local heat buildup and increased component costs, especially during assembly where pressure and temperature stress are applied, resulting in inefficient heat spread and potential hot spots.

Innovation Solution

A prefabricated substrate with a thick first conductor layer for heat absorption and a thin second conductor layer for protection and interconnection, where components are mounted on the thick layer to facilitate efficient heat dissipation, and the substrate is produced using conventional methods without the presence of other components, allowing for improved thermal conductivity and mechanical robustness.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If a thin copper cladding is used on insulating metal substrate, then conductor tracks can be formed by photolithography and etching, but heat dissipation is insufficient leading to local heat buildup

Engineering Contradiction:
Improveconductor track formationVSAvoidheat dissipation
Core Design Contradiction:
Ease of manufactureVSTemperature

Solution Approach 1:

The substrate is divided into two distinct conductor layers: a thick first conductor layer (1-10mm) for heat dissipation and a thin second conductor layer (max 300μm) for conductor track formation. This segmentation allows each layer to optimize its specific function without compromise

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The solution transitions from a two-dimensional thin copper cladding to a three-dimensional layered structure with significant thickness variation. The first conductor layer provides vertical heat spreading capacity while the second layer maintains planar conductor track functionality

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Adaptability or versatility

If step-by-step layer attachment is used to assemble heat-dissipating components, then circuit components can be integrated, but residual air between layers creates hot spots and production becomes complex

Engineering Contradiction:
Improvecircuit integrationVSAvoidhot spot prevention
Core Design Contradiction:
Adaptability or versatilityVSReliability

Solution Approach 1:

The first conductor layer, dielectric, and second conductor layer are manufactured as a single integrated substrate in one production process rather than being assembled separately. This merging eliminates inter-layer air gaps that would create hot spots while maintaining all necessary circuit integration capabilities

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The complete multi-layer substrate structure is pre-manufactured with proper bonding and air elimination before circuit components are mounted. This preliminary formation of the heat dissipation pathway ensures no hot spots are created during subsequent assembly operations

Inventive Principle:
Principle #10Preliminary action

3Strength

If pressure and temperature are applied during assembly of heat-dissipating components, then layers can be bonded, but circuit components are stressed and reliability decreases

Engineering Contradiction:
Improvelayer bondingVSAvoidcomponent stress
Core Design Contradiction:
StrengthVSReliability

Solution Approach 1:

All high-pressure and high-temperature bonding operations are completed during substrate manufacturing before any circuit components are mounted. The substrate arrives at assembly already bonded with full mechanical strength, requiring no additional stress on sensitive components

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The manufacturing process is segmented into two distinct phases: substrate manufacturing (with high P/T bonding) and circuit assembly (with low P/T component mounting). This separation allows optimal bonding conditions without exposing components to damaging stresses

Inventive Principle:
Principle #1Segmentation

4Ease of operation

If individual layer attachment steps are used, then flexible assembly is possible, but production costs increase due to numerous process steps

Engineering Contradiction:
Improveassembly flexibilityVSAvoidproduction cost
Core Design Contradiction:
Ease of operationVSProductivity

Solution Approach 1:

Multiple separate layer attachment operations are merged into a single integrated substrate manufacturing process. This eliminates numerous intermediate steps, reduces production time, and lowers costs while the final substrate maintains all necessary assembly flexibility for circuit integration

Inventive Principle:
Principle #5Merging (Combining)

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

This approach enables simpler, cost-effective production with enhanced heat dissipation, reduced risk of hot spots, and increased reliability by allowing for testing of electrical breakdown strength without affecting other components, while maintaining mechanical integrity and reducing production costs.

Implementation Method 1

The first conductor layer is many times thicker than the second conductor layer and serves to absorb heat directly from a component mounted thereon, which represents a heat source and is to be cooled. Due to the high thickness of the first conductor layer, the heat generated is spread widely.

Methodology Applied
Scientific EffectThermal conduction: Conduction (thermal)

Implementation Method 2

The dielectric following the first conductor layer can transfer the widely spread heat flow with a large passage surface to the second conductor layer.

Methodology Applied
Scientific EffectThermal conduction: Conduction (thermal)

Data Source

PatentEP2609620B1Method for producing an electrical circuit and electrical circuit
Publication Date: 2020.05.13 ROBERT BOSCH GMBH
  • EP2609620B1 patent drawingFigure 1

AI summary

The invention relates to a method for producing an electrical circuit. A prefabricated substrate is provided, said substrate having a first and a second conductor layer and having a dielectric between the first and the second conductor layers. According to the invention, the first conductor layer is multiple times thicker than the second conductor layer. At least one component to be cooled is mounted on the first conductor layer of the prefabricated substrate, forming a heat-transferring connection between the component and the first conductor layer. The invention further relates to an electrical circuit produced in said manner. According to the invention, the electrical circuit comprises a prefabricated substrate which is produced having a first and a second conductor layer and a dielectric located therebetween. According to the invention, the first conductor layer is multiple times thicker than the second conductor layer. At least one component to be cooled is mounted on the first conductor layer. According to the invention, there is a heat-transferring connection between the component and the first conductor layer.