Quantitative morphological and compositional evaluation of laboratory prepared aluminoborosilicate glass surfaces

• Published in: Applied surface science Vol. 324; no. C; pp. 594 - 604
• Main Authors: Gong, Yuxuan, Wren, Anthony W., Mellott, Nathan P.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.01.2015; Elsevier
• Subjects: Atomic force microscopy; Borosilicate glass; Chemical composition; Etching; Fractal analysis; Glass; Heat treatment; Hurst exponent; Mathematical models; Polishing; Roughness; Spectral methods; Surface finishing; X-ray photoelectron spectroscopy; Atomic force microscopy; Hurst exponent; Borosilicate glass; Surface finishing; Spectral methods; Roughness
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2014.10.132

•Aluminoborosilicate glass surfaces were prepared through both melting and polishing/etching and the surface composition and morphology were quantified as a function of processing method.•Glass surface morphology was quantified using PSD analysis, followed by both fractal and ABC model fitting, resulting in a comprehensive description of the spatial distribution of roughness.•All melt surfaces showed a depletion in Na, Ca, and B with respect to the bulk composition. Polished/etched surfaces showed a depletion in Na, B, and Al with respect to the bulk composition.•It was found that increasing heat treatment temperature of melt surfaces lead to a decrease in equivalent roughness and an increased spatial homogeneity of roughness while etching of polished ISG glass surfaces decreases the roughness and spatial distribution homogeneity of roughness. Surface finishing techniques including polishing, etching and heat treatment can modify the topography and the surface chemical composition of glasses. It is widely acknowledged that atomic force microscopy (AFM) can be used to quantify the morphology of surfaces, providing various parameters including average, peak-to-valley, and apparent root-mean-square roughness. Furthermore advanced power spectral density (PSD) analysis of AFM-derived surface profiles offers quantification of the spatial homogeneity of roughness values along different wavelengths, resulting in parameters including equivalent RMS, Hurst exponent, and fractal dimension. Outermost surface (∼8nm) chemical composition can be quantitatively measured by X-ray photoelectron spectroscopy. In this paper, we first developed a series of surface finishing methods for an aluminoborosilicate glass system by polishing, etching or heat treatment. The chemical composition and environment of prepared glass surfaces were quantified by XPS and topographical analysis was carried out by fractal and k-correlation model fitting of PSD profiles derived via AFM. The chemical environment of elements, as determined via XPS, present on the prepared surfaces are similar to those within the pristine bulk glass. The compositional evolution of polished and melt surfaces are discussed in context of corrosion phenomena associated with the grinding, polishing, and etching of surfaces and the thermal heat treatment utilized for processing, respectively. Good correlation between surface finishing methods, chemical composition and topographical parameters were observed. More importantly, extensive discussions on topographical parameters including equivalent RMS, Hurst exponent, and fractal dimension are presented as a function of processing method.