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“This novel instrumentation represents a new type of novel, non-destructive analytical instrumentation, which has shattered the conventional wisdom of IR spectroscopy for advanced packaging analysis and revolutionize submicron infrared spectroscopy into a mainstream, standard process development tool with high ease-of-use.”
The authors report a critical advancement in semiconductor failure analysis through the application of optical-photothermal infrared (O-PTIR) spectroscopy for contamination identification in memory modules.
Lo et al. address fundamental challenges in microelectronic packaging where sub-10μm foreign matter particles cause catastrophic integrated circuit failures, particularly when located in inconvenient locations such as through-holes and bond pads.
The research team identifies that conventional analytical tools including FT-IR, Raman, and SEM-EDX cannot sufficiently provide molecular information for confident contamination analysis due to rough sampling surfaces that create scattering artifacts, distorting infrared absorption bands, and preventing accurate identification of contamination specimens.
The authors demonstrate that O-PTIR spectroscopy successfully achieved high-fidelity chemical identification of foreign particles adhered to plated through-hole walls without physical extraction. They report that the technique provided submicron spatial resolution analysis of contamination particles located several micrometers below the upper rim surface, with spectral data collected across tuning ranges of 2990-2700 cm⁻¹ and 1800-800 cm⁻¹ in 2 cm⁻¹ steps.
The researchers emphasize that O-PTIR spectral band shapes do not suffer from scattering artifacts caused by irregularly shaped sampling surfaces, enabling confident identification of samples and irregularly shaped unknowns previously impossible with conventional FT-IR.
Through spectral matching with commercial databases, the authors successfully identified organic carboxylates as the contamination source, likely introduced during cleaning steps.
The authors conclude that O-PTIR represents a transformative analytical platform for semiconductor contamination analysis, offering unprecedented capabilities for non-contact, non-destructive chemical identification with exceptional spatial resolution.
They report that the technique eliminates cross-contamination possibilities while enabling analysis of subsurface contamination without damaging substrates, establishing O-PTIR as a mainstream standard process development tool that revolutionizes submicron infrared spectroscopy for advanced packaging applications with high ease-of-use.
Authors:
Michael K. F. Lo
Photothermal Spectroscopy Corp, Santa Barbara, CA, USA
Naoki Baden
Nihon Thermal Consulting, Kyoto, Japan
Hanae Kobayashi
Nihon Thermal Consulting, Kyoto, Japan
Norio Urayama
Nihon Thermal Consulting, Kyoto, Japan
