Operando XPS in reactive plasmas: The importance of the wall reactions

Published

May 15, 2026

Author(s)

John Diulus, Ashley Head, J. Anibal Boscoboinik, Andrei Kolmakov

Abstract

Advancements in differential pumping and electron optics over the past few decades have enabled x-ray photoelectron spectroscopy (XPS) measurements at near-ambient pressures, bridging the pressure gap for characterizing realistic sample chemistries. Recently, we demonstrated the capabilities of an ambient pressure XPS (APXPS) setup for in-situ plasma environment measurements, allowing plasma-surface interactions to be studied in operando rather than using the traditional before-and-after analysis approach. This innovative "plasma-XPS" technique facilitates the identification of short-lived reaction intermediates critical to semiconductor nanomanufacturing processes, such as physical vapor deposition, plasma etching, and atomic layer deposition. In this work, we apply plasma-XPS to monitor real-time surface chemical changes on a model Ag(111) single crystal exposed to oxidizing and reducing plasmas. We correlate surface-sensitive data with concurrent gas-phase XPS measurements and residual gas analysis (RGA) of species generated during plasma exposure, highlighting the significant role of plasma-induced chamber wall reactions. Ultimately, we demonstrate that plasma-XPS provides comprehensive insights into both surface and gas-phase chemistry, establishing it as a versatile and dynamic characterization tool with broad applications in microelectronics research. Finally, we outline potential enhancements and future directions to advance plasma-XPS investigations further.

Citation

Journal of Vacuum Science & Technology A

Volume

43

Issue

4

Pub Type

Journals

Download Paper

https://doi.org/10.1116/6.0004569

Local Download

Keywords

Plasma Chemistry, Ag, Operando XPS, APXPS, Plasma-XPS, plasma mass-spectroscopy

Citation

Diulus, J. , Head, A. , Boscoboinik, J. and Kolmakov, A. (2026), Operando XPS in reactive plasmas: The importance of the wall reactions, Journal of Vacuum Science & Technology A, [online], https://doi.org/10.1116/6.0004569, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=959473 (Accessed June 12, 2026)

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