Novel mask removal method for vertical NAND devices

摘要

A method for removing a doped amorphous carbon mask from a semiconductor substrate is disclosed. The method generates a plasma used in processing a substrate, wherein the plasma includes an oxygen-containing gas, a halogen-containing gas, and a hydrogen-containing gas, and processes the substrate by exposing the substrate to the plasma. Including doing. The doped amorphous carbon mask may be an amorphous carbon mask doped with boron or an amorphous carbon mask doped with nitrogen. The method can provide a mask removal rate that ranges from about 1000 angstroms / minute to about 12000 angstroms / minute. Furthermore, gas can be applied to the substrate before plasma treatment, after plasma treatment, or both to reduce the amount of defects or pinholes found in the substrate film.