Isotropic etching is a method commonly used in
semiconductor
A semiconductor is a material which has an electrical conductivity value falling between that of a conductor, such as copper, and an insulator, such as glass. Its resistivity falls as its temperature rises; metals behave in the opposite way. ...
s to remove material from a substrate via a chemical process using an
etchant substance. The etchant may be in liquid-, gas- or
plasma-phase,
although liquid etchants such as
buffered hydrofluoric acid (BHF) for
silicon dioxide
Silicon dioxide, also known as silica, is an oxide of silicon with the chemical formula , most commonly found in nature as quartz and in various living organisms. In many parts of the world, silica is the major constituent of sand. Silica is one ...
etching are more often used. Unlike
anisotropic etching,
isotropic etching does not etch in a single direction, but rather etches in multiple directions within the substrate. Any horizontal component of the etch direction may therefore result in undercutting of patterned areas, and significant changes to device characteristics. Isotropic etching may occur unavoidably, or it may be desirable for process reasons.
References
{{DEFAULTSORT:Isotropic Etching
Semiconductors