Ultrafacility 2025 Roundtable Summary: Identification of Organic Particle Precursors using ATR-IR, SERS and AFM-IR

Organic particle precursors originating from mixed bed ion exchange (MBIX) systems represent an unquantified risk to wafer yield. At Ultrafacility 2025, Padraic O’Reilly of Molecular Vista and Larry Zazzera of CT Associates led a roundtable titled “Identification of Organic Particle Precursors using ATR-IR, SERS and AFM-IR”. The roundtable fostered discussion between industry experts about how brand new advances in analytical techniques can improve the identification and characterisation of these contaminants.

Zazzera provided the Ultrafacility team with a summary of the topic and insight into how the discussion between participants unfolded.

What was the focus of the roundtable discussion?

The discussion focused on recent developments in vibrational spectroscopy methods that enable improved identification of particle precursors, dissolved organic compounds present in ultra-pure water (UPW) that can deposit on wafer surfaces. We found that AFM-IR was able to size, count, and chemically match ATR-IR spectra using 90 nm PSL standards, demonstrating its potential for high-resolution particle characterisation.

Why this is a crucial conversation for the industry?

As semiconductor manufacturing becomes increasingly sensitive to single-digit particle contamination, the industry’s ability to measure and characterize particle precursors is becoming a critical limitation in contamination control. Analytical methods capable of sizing, counting, and chemically speciating particles below 10 nm are necessary in order to better quantify risks to wafer yield.

Were there any particularly interesting points raised by attendees?

Attendees commented that understanding particle size, chemical composition, and reactivity is essential to identify potential particle precursors and to prevent particle adhesion on wafers.

What were the emerging themes or key insights from the roundtable?

Vibrational spectroscopy methods chemically speciate semi-volatile and non-volatile contaminants present as thin films, particles or monolayers on surfaces. These methods form a key part of a multiple analytical method approach to chemically speciate particle precursors and nanoparticles on wafers. Recent advances in vibrational spectroscopy are an opportunity to gain more fundamental insight into critical organic contaminants and their mechanisms of adhesion to wafer surfaces.

Particle precursors remain an important and evolving topic for the industry, with related analysis and insights available on the Ultrafacility portal. Additionally, at the Ultrafacility conference this year the International Roadmap for Devices and Systems (IRDS) presented updates, providing further context on how contamination challenges are expected to evolve. The recording of this presentation can be found here; IRDS and SEMI Spotlight: Yield and Reliability | UltraFacility