Diamond Heat Spreader Assembly for IC Hotspot Mitigation

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Heat mitigation in integrated circuit devices is challenging due to gaps between heatsinks or heat spreaders and IC devices, which can lead to hotspots and thermal resistance, and existing thermal interface materials (TIM) do not provide sufficient thermal conductivity or consistency.

Innovation Solution

Integration of single crystal diamond heat spreaders with filler materials that are bonded to the diamond heat spreader, using a combination of polishing and smoothening materials to achieve accurate height matching and improved thermal conductivity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If thermal interface material (TIM) is used to fill gaps between heat spreader and IC device, then gap filling is achieved, but thermal conductance decreases due to lower thermal conductivity of TIM compared to heat spreader or heatsink

Engineering Contradiction:

Improvegap between interfacesVSAvoidthermal conductance

Core Design Contradiction:

Object-affected harmful factorsVSReliability

Solution Approach 1:

The patent changes the thermal conductivity parameter of the interface material by using materials with progressively higher thermal conductivity (from aluminum oxide to aluminum nitride to diamond), ultimately achieving a thermal conductivity match between the heat spreader and the interface material, thereby eliminating the thermal conductance bottleneck

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent employs composite thermal interface materials, specifically diamond-aluminum nitride composite materials, which combine the high thermal conductivity of diamond with the structural properties of aluminum nitride, achieving both gap-filling capability and high thermal conductance

Inventive Principle:

Principle #40Composite materials

2Manufacturing precision

If lapping, grinding, or polishing is performed on IC device surface and heat spreader surface, then surface flatness and thermal connection are improved, but manufacturing complexity and cost increase

Engineering Contradiction:

Improvesurface flatnessVSAvoidmanufacturing process

Core Design Contradiction:

Manufacturing precisionVSDevice complexity

Solution Approach 1:

The patent performs lapping, grinding, or polishing of the heat spreader surface before final assembly, preparing the surface in advance to ensure optimal thermal contact. This preliminary surface preparation is done on the heat spreader rather than the IC device, simplifying the overall manufacturing process

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent introduces a thermal interface material as an intermediary between the heat spreader and IC device that can accommodate minor surface irregularities, reducing the need for extremely precise surface finishing while maintaining high thermal conductance

Inventive Principle:

Principle #24Intermediary (Mediator)

3Ease of operation

If TIM thickness varies or TIM properties are inconsistent due to outgassing or pressure dependence, then application is simplified, but thermal performance becomes unreliable

Engineering Contradiction:

ImproveTIM applicationVSAvoidthermal conductivity consistency

Core Design Contradiction:

Ease of operationVSReliability

Solution Approach 1:

The patent specifies diamond materials with thermal conductivity of at least 1000 W/m·K (preferably at least 2000 W/m·K), which is an order of magnitude higher than conventional TIM materials, making the thermal interface performance insensitive to thickness variations and property inconsistencies

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent uses thin layers of diamond-like carbon coating (few nanometers to micrometers thick) that can be applied conformally over the heat spreader surface, providing consistent thermal performance without the reliability issues of thicker, pressure-dependent conventional TIMs

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

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

Enhances heat dissipation by leveraging the high thermal conductivity of diamond, reducing thermal resistance and preventing hotspots, thereby improving the reliability and performance of IC devices.

Implementation Method 1

Single crystal diamond has a thermal conductivity of about 2200 Watts per meter Kelvin (W·m−1·K−1), which is about five times greater than the thermal conductivity of copper

Methodology Applied

Scientific EffectThermal conduction: Conduction (thermal)

Implementation Method 2

as-grown or as-sliced diamond surfaces, or diamond surfaces with minimal surface finishing (e.g., lapped, ground, or polished)

Methodology Applied

Scientific EffectAbrasion: Abrasion

Data Source

PatentUS20250357263A1Composite thermal hotspot management in die packaging

Publication Date: 2025.11.20 DIAMOND FOUNDRY INC

AI summary

A device package includes a diamond heat spreader and a filler material bonded to a first side of the diamond heat spreader. A first integrated circuit (IC) device coupled to a second side of the diamond heat spreader opposite the filler material. A second IC device wherein a first side of the filler material opposite of a side bonded to the heat spreader shares a horizontal plane with a top side of the second IC device.