A Technique for Converting Perhydropolysilazane to SiO x at Low Temperature

Spin-coated perhydropolysilazane films on Si(100) substrates were prepared by a dibutyl ether solution and converted into SiO x using a variety of low temperature curing methods. From the Fourier transform IR spectroscopy and the refractive index (RI) measurements, the successful conversion to a high density silica network was observed from the curing methods by dipping the coatings into either diluted H 2 O 2 (for > 10 min) or deionized water under a 405 nm UV irradiation (for >60 min) at near room temperature. The measured RI values of the cured SiO x films were 1.45-1.47, and the X-ray photoelectron spectroscopy showed that the O/Si stoichiometries of the cured SiO x films were in the range of 1.5-1.7.