Anisotropy, growth rate

The anisotropy in the growth rates of the s5uithesis of rock-crystal at an industrial scale is depicted in Figure 10.4 [1]. R is the smallest, the order being... 

F. Iwasaki, H. Iwasaki, and Y. Okabe, Growth rate anisotropy of synthetic quartz grown in Na COj solution,/. Crystal Growth, 178,1999,648-52... 

Hummel and Chang have shown that porous films can also been formed by a spark erosion technique [110]. The morphologies of these porous films exhibit less anisotropy than electrochemically formed porous structures although the pores propagate perpendicular to the surface. The growth rates of about 0.3 nm s are much slower than those of electrochemically formed porous layers. Porous layers formed in air and under nitrogen exhibited visible photoluminescence similar to the emission spectra obtained from electrochemically grown porous layers. 

The degree of anisotropy depended on the purity of melt and a limited stage of the electrociystallization process. The maximum value of growth rate anisotropy of the various monocrystalline planes corresponded to minimum impurity contained in the melt and growth layer, and the slowest stage of electrolysis is the act of crystallization. 

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