Thermal Interface Material Pillars for Heat Transfer
Solution Overview
Problem
Electrical components generate heat that, if not removed, can lead to operating temperatures higher than optimal, affecting their performance and associated devices, and existing thermal interface materials are inefficient in conducting heat away from these components.
Innovation Solution
A thermal interface material assembly comprising a substrate with protruding thermally-conductive pillars and contact resistance reducers, such as solder balls, that soften to improve surface contact and reduce contact resistance, creating an efficient heat path between heat sources and heat dissipating devices.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If conventional thermal interface materials are used to fill the gap between electrical components and heat sinks, then thermal transfer efficiency is improved compared to air gaps, but the thermal conductivity is still insufficient to effectively remove heat from high-power electrical components
Solution Approach 1:
The patent uses a composite structure consisting of a substrate material (such as polymer or metal) combined with an array of thermally conductive pillars (made from materials like aluminum oxide, boron nitride, or metal ceramics) that have high thermal conductivity. This composite architecture allows the TIM to achieve superior thermal transfer efficiency by providing multiple parallel heat conduction pathways through the pillars while maintaining the benefits of the substrate material.
Solution Approach 2:
The thermal interface material is segmented into discrete pillars arranged in an array pattern rather than using a continuous solid material. This segmentation creates multiple independent thermal conduction pathways that can be optimized individually, allowing heat to be distributed and conducted through numerous parallel channels, thereby improving overall thermal transfer efficiency and heat removal effectiveness.
2Temperature
If direct surface contact is made between electrical components and heat sinks, then thermal transfer is maximized, but surface irregularities and gaps reduce the actual contact area and thermal transfer efficiency
Solution Approach 1:
The patent applies local quality by concentrating thermal conduction functionality in specific locations through the pillar array. The pillars are strategically positioned and sized to provide localized high-performance thermal pathways at critical contact points, while the surrounding substrate material provides general support and fills remaining gaps. This local optimization ensures effective thermal transfer even when overall surface flatness varies.
Solution Approach 2:
The pillars act as intermediary elements between the electrical component and heat sink surfaces. Rather than relying on direct surface-to-surface contact, the pillars serve as mediating structures that bridge the gap between irregular surfaces, ensuring consistent thermal contact and transferring heat effectively despite variations in surface precision or flatness.
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 assembly effectively conducts heat away from electronic devices, maintaining optimal operating temperatures and improving thermal transfer efficiency by using pillars with higher thermal conductivity and contact resistance reducers with lower softening temperatures.
Implementation Method 1
The heat sinks may then be cooled by conventional convection and/or radiation techniques. During conduction, the heat may pass from the operating electrical components to the heat sinks
Implementation Method 2
contact resistance reducers, such as solder balls, that soften to improve surface contact and reduce contact resistance
Data Source
AI summary
A thermal interface material assembly generally includes a substrate and one or more pillars protruding outwardly away from the substrate. A thermally-conductive heat path is at least partially defined by the substrate and the one or more thermally-conductive pillars, whereby heat may be transferable along the thermally-conductive heat path from a heat source of an electronic device.