Method and apparatus for forming a thin polymer layer on an integrated circuit structure

Abstract

A method and apparatus are disclosed for forming thin polymer layers on semiconductor substrates. In one embodiment, the method and apparatus include the vaporization of stable di-pxylylene, the pyrolytic conversion of such gaseous dimer material into reactive monomers, and the optional blending of the resulting gaseous p-xylylene monomers with one or more polymerizable materials in gaseous form capable of copolymerizing with the p-xylylene monomers to form a low dielectric constant polymerized parylene material. An apparatus is also disclosed which provides for the distribution of the polymerizable gases into the deposition chamber, for cooling the substrate down to a temperature at which the gases will condense to form a polymerized dielectric material, for heating the walls of the deposition chamber to inhibit formation and accumulation of polymerized residues thereon, and for recapturing unreacted monomeric vapors exiting the deposition chamber. An apparatus is further provided downstream of the deposition chamber to control both the flow rate or residence time of the reactive monomer in the deposition chamber as well as to control the pressure of the deposition chamber. Provision is further made for an electrical bias to permit the apparatus to function as a plasma etch chamber, for in situ plasma cleaning of the chamber between depositions, for enhancing cracking of polymerizable precursor material, for heating the walls of the chamber and for providing heat sufficient to prevent polymerization in the gas phase.