Identification and classification of particle contaminants on photomasks based on individual-particle Raman scattering spectra and SEM images

Abstract

Raman spectroscopy was used for the detection chemical composition of particle contamination on photomasks. Particle types and sources were identified and classified according to the Raman spectra of individual particles.

Advanced procedures in Raman forensic, natural, and cultural heritage studies: Mobile set‐up, optics, and data treatment—State of the art and perspectives

“…Data processing must compensate for the mediocre or even low quality of the spectra. This problem is not new and has been encountered in other disciplines: defects in telescope optics have led to the development of correction tools through calculation 17–19 ; the great variability of biological compounds (medicine, agronomy, and environment) 20–41 and the use of spectral zones where harmonic components and combinations overlap, in a way that it is difficult to identify by visual observation (reflection and NIR absorption), have led to the use in spectroscopy of multivariate analysis techniques (in particular supervised ones)—this scientific discipline is also called chemometrics—applied to all kind of vibrational studies, FTIR, NIR, and Raman (including SERS). Although thousands of papers with this application have been published in agriculture, environment, biology/medicine, and forensic fields from three decades, the number of papers published in the field of heritage 42 is limited (a few tens; see Figure 2 and paragraph 3).…”