화학공학소재연구정보센터
Journal of Vacuum Science & Technology A, Vol.18, No.6, 2827-2834, 2000
Effect of hydrogen dilution on the structure of SiOF films prepared by remote plasma enhanced chemical vapor deposition from SiF4-based plasmas
Structural and electrical properties of fluorinated silicon dioxide (SiOF) films prepared by remote plasma enhanced chemical vapor deposition from the SiF4-O-2-H-2-He gas mixture have been studied using ellipsometry, Fourier transform infrared spectroscopy, transmission electron microscopy, and current-voltage measurements. It has been found that the level of hydrogen dilution strongly affects the microstructure of deposited SiOF films. The films prepared at the H-2 flow rate below about 0.8 seem have a biphase structure consisting of an amorphous matrix with the incorporation of 5-30 nm sized particles. The main origin of these particles seems to be gas phase oxidation of SiFx species (with x = 1, 2, 3) in plasma and downstream regions. Resulting films are characterized by extremely low density, reduced structural homogeneity, and poor electrical properties. Increase in the H-2 how rate above 0.8 seem completely suppresses the incorporation of particles into the growing film probably due to effective hindering gas phase oxidation process and results in dense homogeneous amorphous SiOF films with good electrical properties.