CNT-Based Thermal Interface Material for IC Heat Transfer
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Integrated circuit (IC) devices face inefficiencies in heat transfer due to high thermal contact resistance between the IC die and heat spreaders, leading to non-uniform cooling and potential damage from thermal stress.
Innovation Solution
The use of carbon nanotube (CNT) based thermal interface materials (TIMs) with transition metal-carbon covalent bonds and low melting point layers to reduce contact resistance and enhance thermal conductivity across the interfaces between the IC die, CNTs, and heat spreaders.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional thermal interface materials are used between IC die and heat spreaders, then the structure is simple and easy to manufacture, but high thermal contact resistance occurs leading to inefficient heat transfer
Solution Approach 1:
The patent employs a composite thermal interface material comprising a flexible substrate with integrated carbon nanotube arrays and transition metal layers. This composite structure combines the mechanical flexibility of the substrate with the high thermal conductivity of carbon nanotubes and the bonding capability of transition metals, achieving superior heat transfer efficiency while maintaining manufacturability through a unified material system rather than multiple separate components.
Solution Approach 2:
The invention applies transition metal layers specifically at the interface regions between the carbon nanotubes and the IC die/heat spreader. This localized application of bonding materials addresses the specific need for strong thermal and mechanical contact at the critical heat transfer interfaces, while the bulk of the material maintains its flexible substrate properties for ease of installation and conformability.
2Reliability
If direct contact between IC die and heat spreader is used, then the interface is simple, but non-uniform cooling and thermal stress damage occur
Solution Approach 1:
The flexible substrate with integrated carbon nanotube arrays and transition metal layers provides localized compliance and enhanced bonding specifically at the thermal interface regions. This allows the material to conform to surface irregularities and distribute thermal stress uniformly across the contact area, preventing stress concentration and damage while maintaining a relatively simple overall structure.
Solution Approach 2:
The carbon nanotube arrays serve as an intermediary thermal conduction pathway between the IC die and heat spreader, while the transition metal layers act as intermediaries for mechanical bonding. This intermediate structure decouples the direct mechanical contact requirement, allowing for stress distribution and uniform heat transfer without requiring complex rigid bonding structures.
3Reliability
If high thermal conductivity materials are used at interfaces, then heat transfer efficiency improves, but manufacturing complexity increases
Solution Approach 1:
The patent merges the substrate, carbon nanotube arrays, and transition metal layers into a single integrated flexible thermal interface material. This consolidation eliminates the need for separate assembly steps for multiple components, reducing manufacturing complexity while maintaining the high thermal conductivity benefits of the carbon nanotube-transition metal combination at the critical interfaces.
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
CNT-based TIMs with transition metal-carbon covalent bonds and low melting point layers significantly reduce thermal resistance, enabling more efficient and uniform heat transfer from the IC die to the heat spreader, thereby improving cooling performance and reducing the risk of thermal stress.
Implementation Method 1
carbon nanotube (CNT) based thermal interface materials (TIMs) with transition metal-carbon covalent bonds to reduce contact resistance and enhance thermal conductivity across the interfaces
Implementation Method 2
transition metal-carbon covalent bonds to reduce contact resistance and enhance thermal conductivity across the interfaces
Data Source
AI summary
In an embodiment, a thermal interface material (TIM) is provided. The TIM includes first and a second layers of a first transition metal, and a third layer including a plurality of carbon nanotubes supported in a flexible polymer matrix and a second transition metal coupled to sidewalls of carbon nanotubes. The first and second metal layers are in contact with first and second ends of carbon nanotube. The TIM further includes fourth and fifth layers of an alloy material coupled to the first and second metal layers, respectively. The carbon nanotube based TIM including the layers with transition metal allow improved heat transfer from an integrated circuit die to a heat spreader.