Reactive Ion Pretreatment Technique to Improve the Ashing Resistance of Low Dielectric Constant High Carbon Content Polymer

The oxygen plasma via resist strip process causes significant damage to organic spin on polymer (Allied Signal X-720); thus its inter-level dielectric application is limited. A simple treatment technology, reactive glass stabilization (RGS), using reactive ion is proposed to reform the X-720 film surface. The reactive ion modification of the X-720 film can improve the resistance against oxygen plasma. The measurements of stress, thickness variation, scanning electron microscope (SEM) micrographs of gap filling and dielectric constant show that RGS can be practically used in the low dielectric material application with non-etch-back process. The measurements of fourier transform infrared (FTIR) spectroscopy, and auger electron spectroscopy (AES) show that RGS can effectively reform the surface of the X-720 film and increase the ashing resistance even in high carbon content spin on polymer.