Multilayer Laminate with Oriented Boron Nitride for Heat Dissipation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing laminates face challenges in achieving high thermal conductivity in the thickness direction while maintaining insulation and preventing cracking, particularly in circuit boards with conductive fillers like carbon nanotubes, and previous solutions compromise electrical insulation or mechanical integrity.
Innovation Solution
A laminate structure comprising alternating layers of a support layer and a heat transfer layer with plate-shaped inorganic fillers, such as hexagonal boron nitride particles, oriented perpendicular to the insulating layer, and bonded with a binder resin, ensuring high thermal diffusivity and insulation without cracking.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If a ceramic plate is processed to be thin to reduce thermal resistance in the thickness direction, then heat dissipation performance is improved, but the substrate becomes easily cracked
Solution Approach 1:
The invention uses a composite material consisting of resin and boron nitride powder aggregates instead of pure ceramic plates. This composite structure provides both thermal conductivity and mechanical flexibility, allowing thin substrates to achieve low thermal resistance without being prone to cracking. The boron nitride powder aggregates with voids create a structure that maintains thermal pathways while reducing brittleness.
Solution Approach 2:
The invention utilizes boron nitride powder aggregates containing voids (porous structure) as the filler material. These porous aggregates provide thermal conduction pathways through the solid boron nitride regions while the voids reduce overall density and mechanical stress, preventing crack propagation in thin substrates. The porous structure allows the material to maintain thermal performance while improving crack resistance.
2Temperature
If boron nitride powder is dispersed as filler in the insulating layer, then thermal conductivity is improved, but the powder aligns in the plane direction during coating or press curing, reducing vertical thermal conductivity
Solution Approach 1:
The invention performs preliminary aggregation of boron nitride powder particles before dispersion into the resin. By pre-forming aggregates with voids, the particles are locked in a three-dimensional network structure that resists alignment during subsequent coating or press curing processes. This preliminary aggregation action ensures that the filler maintains its vertical orientation capability throughout manufacturing.
Solution Approach 2:
The invention transitions from considering only two-dimensional particle arrangement (flat dispersion) to three-dimensional aggregated structures. The boron nitride powder aggregates form volumetric structures with voids that extend in the thickness direction, creating thermal pathways that are not confined to the plane direction. This dimensional transition prevents the particles from aligning flat during processing.
3Strength
If aggregated boron nitride powder with high particle strength is used to prevent breakdown, then structural integrity is improved, but resin cannot fill the voids, deteriorating electrical insulation and thermal conductivity
Solution Approach 1:
The invention applies partial filling of the voids within boron nitride powder aggregates. Rather than completely filling all voids with resin, the structure maintains some void space to preserve electrical insulation properties while allowing sufficient resin penetration to provide mechanical binding and partial thermal conduction. This partial filling approach balances structural integrity with electrical and thermal performance.
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 laminate provides excellent heat dissipation and thermal diffusivity in the thickness direction with improved mechanical strength and insulation, reducing thermal resistance and dielectric breakdown risk, suitable for circuit boards.
Implementation Method 1
a heat transfer layer containing at least an inorganic filler and a binder resin... the inorganic filler is substantially perpendicular to an in-plane direction of the laminate... excellent in heat dissipation in a thickness direction, thermal diffusivity in an in-plane direction
Data Source
Figure 1~3
Figure 4
AI summary
There is provided a laminate which is excellent in heat dissipation in a thickness direction, thermal diffusivity in an in-plane direction, and insulation in the thickness direction, and that is not easily cracked. The laminate includes: a metal layer A; an insulating layer provided on at least one surface of the metal layer A, and a metal layer B provided on a surface of the insulating layer opposite to the metal layer A. The insulating layer includes a support layer and a heat transfer layer containing at least an inorganic filler and a binder resin. The support layer and the heat transfer layer are alternately laminated in a total of three or more layers in a direction substantially perpendicular to a thickness direction of the insulating layer.