Non-lithographic line pattern formation

摘要

A metal layer is deposited over an underlying material layer. The metal layer includes an elemental metal that can be converted into a dielectric metal-containing compound by plasma oxidation and/or nitridation. A hard mask portion is formed over the metal layer. Plasma oxidation or nitridation is performed to convert physically exposed surfaces of the metal layer into the dielectric metal-containing compound. The sequence of a surface pull back of the hard mask portion, trench etching, another surface pull back, and conversion of top surfaces into the dielectric metal-containing compound are repeated to form a line pattern having a spacing that is not limited by lithographic minimum dimensions.

主权项

1. A method of forming a patterned structure comprising:
forming a metal layer on an underlying material layer; forming a hard mask portion on said metal layer; converting a first surface portion of said metal layer into a dielectric metal-containing compound portion employing said hard mask portion as a masking structure; and physically exposing a top surface of a second surface portion of said metal layer by isotropically recessing physically exposed surfaces of said hard mask portion, wherein an outer periphery of said second surface portion coincides with an inner periphery of said dielectric metal-containing compound portion and an inner periphery of said second surface portion coincided with a set of bottom edges of sidewalls of a remaining portion of said hard mask portion that overlies a third surface portion of said metal layer which is laterally bounded by said second surface portion after a process that isotropically recessing physically exposed surfaces of said hard mask portion is terminated.