Sensitivity of Etch Rates to Crystal Orientation

FIGURE 7.32. Etch rate ratio of (100)/(111) and (110)/(111) in different etching solutions. Data from Table 7.1. 

The (111) surface is the slowest etching plane in alkaline etchants in all reported 

The fastest etching plane in alkaline solutions, on the other hand, 

FIGURE 7.35. Etch rate of the crystal planes as a function of the deviation from the (111) plane in 40% KOH at 62 °C. (Reprinted with permission from Weirauch. ° 1975, American Institute of Physics.) 

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