New Microscope Tracks Heat Flow at Nanoscale for Greener Tech

A group of Scientists from DTU, Technion, and the University of Antwerp unveiled a new type of microscope designed to capture thermal diffusivity. The device could allow engineers to gain a deeper understanding of how electrons transfer heat through specific materials, opening the door for high-performance components across various industries. Here's what you need to know.

Understanding Thermal Diffusivity in Materials

An item's thermal diffusion capabilities depend largely on its makeup and structure. Being able to determine these properties is a core aspect of engineering reliable and safe devices. It can require monitoring key aspects like electron dispersion relations, atomic mass, bond strength, charge concentration, and mobility, which all play a vital role in the equation. Additionally, when speaking of nanoscale surfaces, crystal grain size, shape, and grain boundaries (GBs) must be examined.

How Heat Flows Differ by Material Structure

When you review all the factors needed to accurately predict heat diffusion, there are two main things to consider. Does the item experience uniform heat flow, meaning the item will gain temperature across its entire surface, or is the item non-uniform? The latter means that thermal diffusivity can vary based on its direction of flow along crystallographic orientations. This type of material provides some unique opportunities to engineers who can utilize the directional heat flow to improve product performance.

Challenges in Measuring Anisotropic Heat Flow

There are some problems when monitoring heat diffusion. To date, there has been no reliable way to determine anisotropic thermal diffusivity tensor in polycrystalline systems structures accurately. This issue reflects scientists’ limited understanding of this nanoscale phenomenon. Also, the current methods are unreliable and can be destructive to the samples. This situation results in reduced accuracy, alongside slow setup. Thankfully, this situation is set to change.

Inside the Study Behind the Thermal Diffusivity Microscope

An international team of engineers has joined forces to tackle this issue. The study¹ “Thermal diffusivity microscope: Zooming in on anisotropic heat transport,” published in Science Advances, introduces a novel method to reliably record high-resolution local measurements of anisotropic thermal diffusivity. Their invention, the thermal diffusivity microscope, has the potential to open the door for a new level of engineering and material science.

What Is the Thermal Diffusivity Microscope?

The thermal diffusivity microscope concept borrows concepts from the CAPRES microRSP automated system and combines them with upgrades that enhance heat flow measurement capabilities. The new device features a proprietary four-point probe that delivers faster and more accurate measurements.

Fast Setup and Calibration-Free Design

The team noted that the device can be set up and doesn’t require calibration between every reading. Also, the sample requires minimum prep, reducing the workload and the chance for contamination. Notably, the system delivers accurate anisotropic thermal diffusivity measurements utilizing data collected from a thermal relay located on a single heater.

Incorporating Cold Finger Effects in Heat Studies

Another issue that engineers addressed was the “cold finger” effects. A cold finger refers to a lab tool that resembles a metal cylinder. It's designed to lower the temperature of items and assist in processes like distillation. It's commonly used, but its effects have never been integrated into a thermal diffusion study until now.

Testing the Microscope with Real Materials

The team conducted several experiments to test their theories. They selected two materials known for their thermal capabilities – Bi2Te3 (bismuth telluride) and Sb2Te3 (antimony telluride). Both provide high conduction and thermal properties that make them ideal for nanoscale use. Also, these materials have a rhombohedral layered crystal structure stacked by weak van der Waals forces along the c-axis, furthering their anisotropic transport properties.

To begin, the samples were heated up before the engineers randomly mapped 300 μm–by–400 μm section with step size of 5 μm. This optical micrograph showed key details like grains and the orientation of probes. This helped engineers to see changes in thermal diffusivity based on the orientation of the grains.

Key Findings from the Thermal Diffusivity Microscope Tests

The thermal diffusivity microscope tests revealed that the engineers were correct in their models. The device successfully provided high-resolution measurements on a nanoscale. The measurements enabled engineers to watch heat flow in real time, allowing them to determine key factors about the tested materials, including how the lattice contribution was critical to the heat transport for both directions.

Benefits of the Thermal Diffusivity Microscope for Engineers

There's a long list of benefits that the thermal diffusivity microscope brings to the market. For one, it will help engineers create more powerful and safer electronic devices and energy systems. They can test new materials on a nanoscale and see exactly when the failure point occurs and where.

User-Friendly and Non-Destructive Setup

The thermal diffusivity microscope system requires far less work than previous methods. There is no need to prep samples, which was a time-consuming and exact process that often resulted in the samples being damaged. The team noted that they could obtain detailed and mapped measurements in less than a minute.

Real-World Applications and Rollout Timeline

The list of applications for this tech is nearly endless. Thermal diffusivity is at the core of most high-tech development. Everything from your personal computer to spacecraft requires heat management systems. This device will enable engineers to create more capable and powerful thermal coatings, electronics, and thermoelectric devices. Here are some top applications for this tech.

Faster Computers

The thermal diffusivity microscope will help make better computers. Your device experiences lowered performance when exposed to prolonged heat levels. Maintaining cooler PCs will allow engineers to create more powerful and smaller devices.

Solar Panels

Another sector where this tech could shine is in the solar industry. Any device that needs to capture sun rays should have excellent thermal diffusivity. Engineers will be able to push the boundaries of this technology to new heights by creating more heat-efficient and cooler-running options, reducing unintentional energy loss through heat mismanagement.

Thermal Diffusivity Microscope Timeline

The thermal diffusivity microscope is operational. However, it could be a few years before this device can make its way to commercial clientele. For now, the device will undergo a lot more experimentation and testing. In the next 3-5 years, the unit could be commercialized and become a powerful tool for manufacturers, safety personnel, and engineers.

Thermal Diffusivity Microscope Researchers

The thermal diffusivity microscope study was a collaborative effort by engineers from DTU, Technion, and the University of Antwerp. The paper lists Neetu Lamba, Braulio Beltrán-Pitarch, Tianbo Yu, Dirch Hjorth Petersen, Muhamed Dawod, Alex Berner, Benny Guralnik, Andrey Orekhov, Nicolas Gauquelin, Yaron Amouyal, Johan Verbeeck, Ole Hansen, and Nini Pryds as contributing authors. The study received financial support from a variety of grants, including the Independent Research Fund Denmark grant, the Innovation Fund Denmark grant, the EliteForsk travel grant, and many more.

What’s Next for the Thermal Diffusivity Microscope

The future of the thermal diffusivity microscope is busy. This technology can be rolled out across several industries and will have a direct impact on everything from your smartwatch, all the way to the next EV. This research could open the door for engineers to obtain a deeper understanding of thermal properties and expand materials science.

Investing in the Thermal Spray Coating Market

There are a lot of companies in the thermal coating industry that could benefit from this research. Notably, the market is predicted to hit $20.83B by 2030, driving demand for innovation and improved products. Here's one company that continues to attract investor attention due to its products and business model.

Applied Materials

Applied Materials (AMAT -2.52%) is a Santa Clara, California-based wafer fabrication firm. The company was founded in 1967 by Michael A. McNeilly, Herbert Dwight Jr., Walter Benzing, and James Bagley. Their goal was to provide reliable chemical vapor deposition (CVD) systems specifically designed for semiconductor wafer fabrication.

Since its launch, Applied Materials has grown to become the world’s largest semiconductor equipment manufacturer. In 1993, the company was the first to secure $1 billion in annual revenue in the wafer industry. Today, the firm operates across several advanced sectors, offering a comprehensive portfolio of rapid thermal processing (RTP) and anneal systems in the market.

Applied Materials has research centers in India and Israel as part of its growth strategy. Notably, analysts predict that Applied Materials will see growth as demand for its products increases alongside the need for more powerful computers to handle global AI system adoption. Consequently, those seeking exposure to the thermal coating sector should do more research into AMAT.

Final Thoughts: Empowering Next-Gen Technologies

The thermal diffusivity microscope will open the door for more advanced tech in the coming years. This device will undergo several iterations, making it smaller and more available to engineers and businesses. These changes will help to drive adoption, resulting in more advanced heat coatings, electronics, and more. All of these factors reflect the upending potential of the thermal diffusivity microscope study.

Learn about other Scientific breakthroughs here.

Studies Referenced: