Rate determining processes anisotropic etching

Mechanism of Anisotropic Etching. The rich details as to anisotropic etch rates, nature of reactions, and surface topography indicate that a complex mechanism is involved in silicon etching in alkaline solutions. A coherent mechanistic model has to address three basic aspects (1) the physical cause of the difference in the removal rates of atoms from the surface of different crystal orientations, (2) the kinetic processes that actualize such physical cause, and (3) the surface condition that determines the global removal rate of the surface atoms. 

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