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Updated: Sep 17, 2025
11:10
Atomic Layer Deposition of Vanadium Dioxide and a Temperature-dependent Optical Model
Published on: May 23, 2018
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Multilayer W-doped vanadium dioxide thermal sensors with extended operation region
Callum Wheeler1,2, Yuxiao Zhu1, Kai Sun1,2
1Electronics and Computer Science, Faculty of Engineering and Physical Sciences, University of Southampton, SO17 1BJ Southampton, UK.
Iscience
|July 4, 2025
Summary
Multilayer tungsten-doped vanadium dioxide (W:VO2) thin films were fabricated using atomic layer deposition for improved infrared detection. Optimized W:VO2 bolometer sensors show enhanced performance over a wider temperature range.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Infrared Technology
Background:
- Bolometers detect infrared radiation using materials with a temperature coefficient of resistance (TCR).
- Vanadium dioxide (VO2) has a large TCR but a narrow, abrupt phase transition.
- Tungsten doping (W-doping) in VO2 modifies and broadens this transition temperature.
Purpose of the Study:
- To develop a W:VO2 sensing layer with an extended operational temperature range for uncooled bolometers.
- To optimize the multilayer W:VO2 structure for enhanced TCR performance.
Main Methods:
- Fabrication of multilayer W:VO2 thin films using atomic layer deposition (ALD).
- Characterization of the TCR of the W:VO2 films.
- Simulation of a 10-layer W:VO2 structure using a multi-objective genetic algorithm (MOGA) to optimize TCR and its variation.
Main Results:
- The fabricated W:VO2 film exhibited an average TCR of -9.5 (±3.5) %K-1 between 30°C and 60°C.
- The MOGA simulation optimized a 10-layer W:VO2 structure for maximum |average TCR| - variation.
- The optimized structure achieved an average TCR of -6.7 (±0.9) %K-1 across a broader range of 20°C to 70°C.
Conclusions:
- Multilayer W:VO2 thin films fabricated by ALD offer a promising approach for uncooled bolometer applications.
- Optimizing the layer structure through simulation can significantly enhance bolometer performance over extended temperature ranges.
- This work demonstrates the potential for broader application of W:VO2 in advanced infrared sensing technologies.
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