2026-09-18T18:54:59Z https://www.ideals.illinois.edu/oai-pmh

oai:www.ideals.illinois.edu:2142/132746 2026-03-24 col_2142_5131 col_2142_13836 com_2142_5130 com_2142_13835 com_2142_234

application/pdf en text Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2027-12-01 The student, Jinchi Sun, accepted the attached license on 2025-10-08 at 23:02. The student, Jinchi Sun, submitted this Dissertation for approval on 2025-10-09 at 08:44. This Dissertation was approved for publication on 2025-10-10 at 09:07. DSpace SAF Submission Ingestion Package generated from Vireo submission #22823 on 2026-02-19 at 20:08:32 Thermo-optic Phase Spectroscopy techniques for multiscale thermal conductance characterization in semiconductor integrated circuits Sun, Jinchi 2025-10-10 Cahill, David G. Cahill, David G. Cao, Qing Sinha, Sanjiv Anderson, Christopher P. Thermo-optic Phase Spectroscopy (TOPS) Thermal conductance characterization Semiconductor integrated circuits AC laser heating Probe beam deflection Multiscale thermal analysis 3D IC architectures Buried interfaces Thermal boundary conductance Nanoscale thin films eng Thermal management remains a critical challenge in the advancement of semiconductor integrated circuits, particularly with the emergence of three-dimensional (3D) architectures for high-performance applications. This thesis introduces Thermo-optic Phase Spectroscopy (TOPS), a family of non-destructive techniques for multiscale thermal conductance characterization across bulk materials, buried films and interfaces, and nanoscale films. Three variants are developed: Displacement TOPS (D-TOPS) for bulk solids, Immersion TOPS (I-TOPS) for deeply embedded films and interfaces, and High-Resolution TOPS (HR-TOPS) for nanoscale semiconductor films. Each technique combines AC laser heating, temperature sensing via probe beam deflection, and analytical modeling to extract thermal properties with high spatial resolution, sensitivity, and speed. A unified modeling framework accommodates multilayer structures with anisotropic thermal expansion and elastic constants. Experimental validation demonstrates TOPS’s ability to extract thermal conductivity and thermal boundary conductance with improved accuracy and reduced acquisition time compared to conventional methods. By enabling precise thermal conductance characterization across multiple scales, TOPS provides essential data for optimizing fabrication processes, improving thermal simulations, and guiding temperature sensor placement in next-generation IC designs. 2025-12 Thesis https://hdl.handle.net/2142/132746 Copyright 2025 Jinchi Sun Materials Science & Engineerng Materials Science & Engr University of Illinois Urbana-Champaign Ph.D. Dissertation