Etching techniques are used to remove material from wafers. In wet chemical etching processes, the wafers are immersed in a liquid solution, which removes the unwanted material. When used in combination with deposition and photolithography, etching allows the removal of material in patterns defined by the masks containing the shapes and sizes of the desired structures. Dry etch is etching with a beam (plasma or ionic.)

There are several dry etching and wet etching techniques and each is used for different purposes. The techniques differ in the quality of the etch achieved, the level of detail the etch can achieve, the exact shape of the edges of the etched material, the material you are trying to etch, and the cost.

Dry Etch	Wet Etch

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