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Updated: Dec 11, 2025
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Atomic Layer Deposition of Vanadium Dioxide and a Temperature-dependent Optical Model
Published on: May 23, 2018
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Experimental demonstration of dynamic thermal regulation using vanadium dioxide thin films
Ahmed M Morsy1, Michael T Barako2, Vladan Jankovic2
1Ming Hsieh Department of Electrical and Computer Engineering, University of Southern California, Los Angeles, 90089, USA. morsy@alumni.usc.edu.
Scientific Reports
|August 20, 2020
Summary
This study demonstrates a solid-state device using vanadium dioxide (VO2) for dynamic thermal regulation. The VO2 thin film device passively controls temperature by switching thermal emissivity, outperforming constant emissivity materials.
Area of Science:
- Materials Science
- Solid-State Physics
- Thermal Engineering
Background:
- Effective thermal management is crucial for electronic devices and spacecraft.
- Passive thermal regulation systems offer advantages in simplicity and reliability.
- Dynamic control of thermal properties, such as emissivity, can enhance regulation capabilities.
Purpose of the Study:
- To experimentally demonstrate passive, dynamic thermal regulation using a solid-state system.
- To investigate the temperature-dependent thermal emissivity switching of vanadium dioxide (VO2).
- To validate a thermal model for predicting device performance, particularly in space applications.
Main Methods:
- Fabrication of a multilayered device with a VO2 thin film on a silicon substrate and a gold back reflector.
- Experimental characterization of the optical properties of the VO2 film.
- Calibrated transient calorimetry to measure temperature fluctuations under a time-varying heat load.
Main Results:
- The developed device exhibits passive, dynamic thermal regulation through temperature-dependent thermal emissivity switching.
- Experimental results show the device regulates temperature more effectively than a constant emissivity sample under laboratory conditions.
- The validated thermal model predicts a halving of thermal fluctuations in space conditions compared to constant emissivity.
Conclusions:
- The VO2-based solid-state device provides effective passive thermal regulation.
- The demonstrated technology has significant potential for thermal management in space applications.
- Dynamic emissivity switching is a viable strategy for enhancing passive thermal control systems.
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