Comparison of film formation methods using amine-terminated alkyltrialkoxysilane precursors

CHED 285

Wynter E. Gilson, wynter_eve@hotmail.com, Jacob D. Acton, jda2k@mtsu.edu, John W. Cline, jwc2s@mtsu.edu, Gale G. McPherson, ggm2a@mtsu.edu, Adam F. Farmer, aff2a@mtsu.edu, and Andrienne C. Friedli. Department of Chemistry, Middle Tennessee State University, Box X076 MTSU, Murfreesboro, TN 37132
Surface wave sensors require an interfacial organic layer to attach a chemical probe molecule to a multilayered photonic band gap material. Seeking to optimize film quality and surface coverage, we compared short and long-chain ù-aminoalkyl trimethoxysilane precursors using two film formation methods, vapor and solution deposition. Rigorously cleaned quartered silicon wafers were exposed to solution or vapor of either 10-aminodecyl trimethoxysilane or 3-aminopropyl triethoxysilane for time periods ranging from 15 min to 24 h, rinsed, and cured at 110 °C for 10 min. Characterization techniques included contact angle goniometry and spectroscopic ellipsometry. In solution deposition, deposition times for films of a given thickness were proportional to organosilane concentration and chain length. Reproducibility, thickness control, film quality, and ease of preparation were maximized with solution deposition. Thin films produced with vapor deposition were dependent upon sample placement and direction of vapor source.