Process for forming a low k carbon-doped silicon oxide dielectric material on an integrated circuit structure

Abstract

A process for forming a low k carbon-doped silicon oxide dielectric material (lkc-dsodm) on an integrated circuit structure is characterized by improved planarity and good gap fill in high aspect ratio regions of the integrated circuit structure, as well as improved film strength and adherence, and less byproducts trapped in the film. The process comprises: depositing a plurality of layers of lkc-dsodm on an integrated circuit structure in a reactor; and pausing after depositing each layer of lkc-dsodm and before depositing a further layer of lkc-dsodm. The process can further include first forming a base or barrier layer of a silicon-rich and nitrogen-rich dielectric material over the integrated circuit structure, plasma etching the upper surface of the barrier layer to facilitate adhesion of the subsequently deposited lkc-dsodm to the barrier layer, and then, before depositing the first layer of lkc-dsodm, cooling the etched barrier layer down to within 10° C. or less of the subsequent deposition temperature used for formation of the film of lkc-dsodm. In another aspect of the invention the pausing step further includes, before deposition of the next layer of lkc-dsodm, flowing a source of non-reactive gas over the surface of the newly deposited layer of lkc-dsodm to facilitate outgassing and removal of byproducts resulting from the preceding formation and deposition of lkc-dsodm.