A Switchable Longitudinal & Shear BLS Microscope for Comprehensive Modulus Imaging of Semiconductor Packaging Materials

Published

June 17, 2026

Author(s)

Andrew Gayle, Sebastian Engmann, Ran Tao, Andrew Korovich, Polette Centellas, Yvonne Gerbig, Christopher Soles, Chris Michaels

Abstract

Brillouin light scattering (BLS) offers an optical, noncontact, nondestructive method for probing the mechanical properties of next-generation semiconductor packaging materials. In this work, a switchable BLS microscope with both backscattered and off-axis configurations is presented. The microscope can be used for comprehensive modulus imaging, including longitudinal modulus, Young's modulus, shear modulus, bulk modulus, and Poisson's ratio. The capabilities of this microscope are demonstrated by measuring two proof-of-concept heterogeneous samples, including a polymer with two different degrees of cure (DoC) and a polymer with silica filler particles present. The modulus measurements performed by BLS are compared to results from conventional modulus measurement techniques, including nanoindentation (NI) and dynamic mechanical analysis (DMA). The BLS-derived modulus values are larger than those collected using NI and DMA due to differences in the frequency domain of the measurements, but are in agreement with literature trends. This microscope platform will be useful in evaluating mechanical heterogeneities in semiconductor packaging materials, to aid in the development of new packaging materials and standards, as well as providing insights to limit warpage issues in these materials.

Citation

2026 IEEE 76th Electronic Components and Technology Conference (ECTC)

Pub Type

Journals

Download Paper

https://doi.org/10.1109/ECTC51846.2026.00313

Local Download

Keywords

Brillouin light scattering spectroscopy, microscopy, imaging, mechanical properties, packaging polymers

Citation

Gayle, A. , Engmann, S. , Tao, R. , Korovich, A. , Centellas, P. , Gerbig, Y. , Soles, C. and Michaels, C. (2026), A Switchable Longitudinal & Shear BLS Microscope for Comprehensive Modulus Imaging of Semiconductor Packaging Materials, 2026 IEEE 76th Electronic Components and Technology Conference (ECTC), [online], https://doi.org/10.1109/ECTC51846.2026.00313, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=961664 (Accessed July 29, 2026)

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