Nano-scale modification of ionic surfaces induced by electronic transitions

• Published in: Progress in surface science Vol. 67; no. 1; pp. 123 - 138
• Main Authors: Szymonski, M., Kolodziej, J., Such, B., Piatkowski, P., Struski, P., Czuba, P., Krok, F.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-08-2001
• Subjects: Alkali halides; Electron- and photon-stimulated desorption (PSD, ESD); Frenkel defects; Non-contact atomic force microscopy (NC-AFM); Radiation damage; Surface modification; Surface structure, morphology, roughness, and topography; Thin films; 79.20.La; 71.35.Aa; 61.16.Ch; Surface modification; Electron- and photon-stimulated desorption (PSD, ESD); Surface structure, morphology, roughness, and topography; Frenkel defects; Thin films; 68.35.Bs; Alkali halides; 61.82.Ms; Non-contact atomic force microscopy (NC-AFM); Radiation damage
• ISSN: 0079-6816; 1878-4240
• DOI: 10.1016/S0079-6816(01)00019-3

This paper presents a review of recent experimental and theoretical work on surface modification of alkali halides due to electronic excitations caused by electron and photon irradiation. In particular, several examples of free exciton and hot electron–hole pair formation in ionic materials are given. It is demonstrated that evolution of these primary excitations with subsequent defect formation and diffusion from the bulk to the surface, leads to dynamic surface modification and sputtering, often periodically varying with the irradiation dose. In turn, modification of the surface topography could affect and modulate periodically, the diffusion processes driving the defects from the bulk of the material towards its surface. Spectacular examples of such oscillatory yield dependencies, and corresponding surface nano-structure formation and evolution, are shown for electron- and photon-irradiated NaCl, KBr and KCl(0
0
1) surfaces of bulk crystals and thin epitaxial films. Important applications of these findings for quantitative characterisation of insulator surfaces and mass spectrometry are presented.