(95p) Applications of Supercritical Carbon Dioxide: Repair and Capping of Porous Msq Films Using Chlorosilanes

Chemical batch reactions between chlorosilanes and porous methylsilsesquioxane films (p-MSQ) were performed using supercritical CO2 as a solvent in order to produce a hydrophobicity state and low dielectric constant to p-MSQ films. Chlorosilanes produced chemical bonds of methylsilyl(-O-Si-CH3) motieties by reaction of H-bonded, geminal/isolated silanol groups on the surface of the films. Chemical reactions produced an effect in hydrophobicity and dielectric constant. Fourier transform infrared (FTIR) spectroscopy, spectroscopic ellipsometry, goniometry, Ti CVD, XPS and electrical measurements were used as analytical instruments to measure the repair and capping of p-MSQ. Trimethylchlorosilane(TMCS), dimethyldichlorosilane(DMDCS) and methyltrichlorosilanes(MTCS) were used as Chlorosilanes. Blanket p-MSQ films with a dielectric constant of 2.4 before oxygen ashing and 3.5 after oxygen ashing were processed by supercritical condition batch process reactor using a 2 minute steady state ( range of 50°C to 60°C and 160 atm to 190 atm condition state). After treatment to p-MSQ, goniometry shows contact angles greater than 79.4°, FTIR presents diminish of silanol groups and increase of methyl groups. TI CVD and X-ray photoelectron spectroscopy (XPS) showed that p-MSQ were capped after reactions with DMDCS, and MTCS. Electrical measurement shows that dielectric constant k were reduced to 2.59 ± 0.05 by TMCS, 2.88 ± 0.13 by DMDCS, and 3.23 ± 0.11 by MTCS. Future work will involve applications of chlorosilanes combination on the p-MSQ in order to observe the results of hydrophobicity and capping.