This book (Practical Electron Microscopy and Database) is a reference for TEM and SEM students, operators, engineers, technicians, managers, and researchers.
 

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The clustering of vacancies into dislocation loops may occur when point defects become supersaturated. The saturation of point defects can be induced by many ways such as high-energy-particle irradiation, plastic deformation, or thermal quenching [1 - 6].

For PCM (phase change memory) materials, typical quenching rates to glass states are 10⁹-10¹⁰ °C/s. By applying an external electrical field, the crystallization time can be reduced to several hundreds of picoseconds [7].

[1] Yoo, M. H. & Stiegler, J. O. Point defect interactions and growth of dislocation loops. J. Nucl. Mater. 69–70, 813–815 (1978).
[2] Abromeit, C. & Wollenberger, H. Insight into cascade processes arising from studies of cascade collapse. Mater. Sci. Forum 15–18, 1003–1022 (1987).
[3] Davis, T. L. & Hirth, J. P. Nucleation rate of vacancy clusters in crystals. J. Appl. Phys. 37, 2112–2116 (1966).
[4] Davis, T. L. Nucleation rate of vacancy clusters in aluminum. J. Appl. Phys. 38, 3756–3760 (1967).
[5] Kino, T. & Koehler, J. S. Vacancies and divacancies in quenched gold. Phys. Rev. 162, 632–648 (1967).
[6] Bauerle, J. E. & Koehler, J. S. Quenched-in lattice defects in Gold. Phys. Rev. 107, 1493–1499 (1957).
[7] Loke D, Lee TH, Wang WJ, Shi LP, Zhao R, Yeo YC, et al. Breaking the speed limits of phase-change memory. Science 2012, 336(6088): 1566-1569.