2026-09-22T06:07:54Z https://www.ideals.illinois.edu/oai-pmh

oai:www.ideals.illinois.edu:2142/129634 2026-02-05 col_2142_5131 col_2142_8888 com_2142_5130 com_2142_8887 com_2142_234

application/pdf en text Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2027-05-01 The student, Sandhya Ashok, accepted the attached license on 2025-05-06 at 11:13. The student, Sandhya Ashok, submitted this Thesis for approval on 2025-05-06 at 11:15. This Thesis was approved for publication on 2025-05-06 at 19:27. DSpace SAF Submission Ingestion Package generated from Vireo submission #22227 on 2025-10-19 at 19:17:05 Characterization of infrared imaging systems Ashok, Sandhya 2025-05-06 Bhargava, Rohit Infrared Imaging Systems Imaging Systems Characterization Fabrication Microfabrication Fourier Transform Infrared Imaging FTIR eng This thesis explores the characterization of infrared (IR) imaging systems by microfabricating and analyzing USAF targets with varying thicknesses (0.6 μm to 5.3 μm) using SU-8 photoresist. The targets were fabricated in a cleanroom environment to ensure controlled conditions and high precision. Designed with well-defined USAF patterns, they served as reliable test samples to assess spectral accuracy and resolution capability due to their tailored and precisely measured parameters. Comparative thickness measurements using surface profilometry (DekTak3ST) and laser confocal microscopy (Keyence VK-X1000) revealed that surface profilometry was more accurate for thin films (< 1 μm) due to challenges in resolving transparent film surfaces via confocal microscopy. High-resolution profiles of USAF targets demonstrated a superior edge quality in laser confocal profiling with 0.08 μm pitch size but were prone to negative artifacts due to the same resolution issue. The Varian 620-IR FTIR imaging system was used to acquire spectra, and 1608 cm⁻¹ peak (aromatic C=C) was analyzed, to evaluate spectral fidelity. While the results followed Beer-Lambert law by showing increasing absorbances for thicker films, thicker films presented baseline linearity challenges. This dataset of well characterized targets provides a strong foundation for validating future IR instrument accuracies as well as IR simulation models. 2025-05 Thesis https://hdl.handle.net/2142/129634 Copyright 2025 Sandhya Ashok Electrical & Computer Eng Electrical & Computer Engr University of Illinois Urbana-Champaign M.S. Thesis