Specific Process Knowledge/Etch/KOH Etch

From LabAdviser

KOH etch - Anisotropic silicon etch

KOH etch for 4" wafers: positioned in cleanroom 3

KOH belongs to the family of anisotropic Si-etchants based on aqueous alkaline solutions. The anisotropy stems from the different etch rates in different crystal directions. The {111}-planes are almost inert whereas the etch rates of e.g. {100}- and {110}-planes are several orders of magnitude faster.

At Danchip we use as a standard a 28 wt% KOH.