Optical Detection of Coefficient of Thermal Expansion via Frequency Tracking at Cryogenic Temperatures
Abstract
Accurate characterization of the coefficient of thermal expansion (CTE) in nanoscale thin films is critical for predicting residual stress and ensuring the reliability of modern micro-electromechanical systems and advanced semiconductor architectures. The primary limitation is that traditional methods depend on precise thickness measurements or are restricted to crystalline materials. In this work, we present an in-situ, non-destructive optical methodology to determine the CTE of suspended nanofilms by tracking the temperature-dependence of their vibrational frequency. This approach eliminates thickness measurements entirely and works for amorphous films where X-ray diffraction (XRD) fails. We experimentally validate this technique across a broad temperature range, evaluating membranes in their native microstructure state without requiring additional destructive patterning or complex sample preparation. This non-contact optical method achieves uncertainty below 5.3 * 10-8 K-1, substantially improving upon conventional thin-film CTE metrology.
Related
- Strain engineering of transient exciton diffusion in WSe2 monolayers at cryogenic temperatures
- Realization of ZnSe-based Field-Effect Transistors operating at Cryogenic Temperatures as a Platform for Future Spin-Qubit Applications
- All-photonic millimeter-wave and terahertz signal core at room and cryogenic temperatures
- Infrared free electron laser induced photodesorption of CO and N₂ from solid amorphous water at cryogenic temperatures
- Cryogenic Optical Characteristics of S-FPL51 and S-LAH71: Refractive index, Transmission and Thermal expansion
BibTeX
@misc{shi2026optical,
title = {{Optical Detection of Coefficient of Thermal Expansion via Frequency Tracking at Cryogenic Temperatures}},
author = {Yanli Shi and Hui Wu and Guangyu Li and Qun Cao and Zhe He and Zheng Cui},
howpublished = {arXiv},
year = {2026},
month = nov,
doi = {10.48550/arxiv.2611.02347},
eprint = {2611.02347},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2611.02347},
note = {CC BY-NC-ND 4.0},
}
RIS
TY - UNPB
TI - Optical Detection of Coefficient of Thermal Expansion via Frequency Tracking at Cryogenic Temperatures
AU - Yanli Shi
AU - Hui Wu
AU - Guangyu Li
AU - Qun Cao
AU - Zhe He
AU - Zheng Cui
PY - 2026
DA - 2026/11/02
PB - arXiv
DO - 10.48550/arxiv.2611.02347
UR - https://arxiv.org/abs/2611.02347
AB - Accurate characterization of the coefficient of thermal expansion (CTE) in nanoscale thin films is critical for predicting residual stress and ensuring the reliability of modern micro-electromechanical systems and advanced semiconductor architectures. The primary limitation is that traditional methods depend on precise thickness measurements or are restricted to crystalline materials. In this work, we present an in-situ, non-destructive optical methodology to determine the CTE of suspended nanofilms by tracking the temperature-dependence of their vibrational frequency. This approach eliminates thickness measurements entirely and works for amorphous films where X-ray diffraction (XRD) fails. We experimentally validate this technique across a broad temperature range, evaluating membranes in their native microstructure state without requiring additional destructive patterning or complex sample preparation. This non-contact optical method achieves uncertainty below 5.3 * 10-8 K-1, substantially improving upon conventional thin-film CTE metrology.
ER -