CMP
Chemical mechanical planarisation (CMP), often called chemical mechanical polishing, is a procedure to level thin layers. CMP was originally developed for use with typical semiconductor materials but is also being increasingly used in manufacturing micro systems. CMP is essential for low-K materials and in the manufacture of sensitive wafers whose surface consists of two materials made from one material compound, for example. Due to the different hardnesses and electricity of both materials, purely mechanical processing in this case would lead to notches in the material transition areas.