In situ FTIR investigation of MMA plasmas, plasma-polymerized films, and reaction mechanisms

✍ Scribed by Y. Vickie Pan; Ernesto Z. Barrios; Denice D. Denton

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 339 KB
• Volume: 36
• Category: Article
• ISSN: 0887-624X
• DOI: 10.1002/(sici)1099-0518(199803)36:4<587::aid-pola8>3.0.co;2-m

✦ Synopsis

Methyl methacrylate (MMA) plasmas and plasma-polymerized methyl methacrylate (PPMMA) films were studied in situ with FTIR and FTIR/ATR (attenuated total reflection) in an r.f. capacitively coupled glow discharge. A statistically designed experiment was conducted by varying the r.f. power, process pressure, and MMA flow rate. MMA plasma fragments were identified from the gas-phase FTIR measurements. They include the intermediate species such as dimethylketene, formaldehyde, allene, and propene; small hydrocarbons such as acetylene, methane, and ethylene; and oxygenates such as carbon dioxide, carbon monoxide, and methanol. Statistical analysis techniques (correlation analysis, analysis of variance and regression analysis) were used on both gas and film data. Gas-phase reaction mechanisms are proposed, and the relationship between the gas and film data is investigated to understand the film deposition chemistry. The deposition rate is positively correlated to the relative concentrations of MMA fragments which are identified as the major film precursors in the deposition process.