When designing a microfabrication process, the etch rate of each material to be etched must be known. Knowing the etch rates of other materials that will be exposed to the etch, such as masking films and underlying layers, enables an etch process to be chosen for good selectivity (high ratio of etch rate of the target material to etch rate of the other material)—if one exists. These two papers compare the etch rates of different materials in various etchants
K. R. Williams and R. S. Muller, "Etch rates for micromachining processing," in Journal of Microelectromechanical Systems, vol. 5, no. 4, pp. 256-269, Dec 1996.
K. R. Williams, K. Gupta and M. Wasilik, "Etch rates for micromachining processing-Part II," in Journal of Microelectromechanical Systems, vol. 12, no. 6, pp. 761-778, Dec. 2003.
doi: 10.1109/JMEMS.2003.820936
doi: 10.1109/JMEMS.2003.820936
