Effect of the C-bridge on UV properties of organosilicate films

Abstract

Carbon-bridged organosilicate films deposited by using different precursors are studied by both experimentally and theoretically. It is shown that carbon-bridged OSG films have higher Young Modulus (E) than methyl-terminated films and E(phenylene) > E(ethylene) > E(methylene). However, the k-values of these films show the same tendency and this is one of the drawbacks of carbon terminated materials when they are considered as low-k candidates. It is shown that the films having a phenylene bridge can be destructed by UV light with wavelength > 200 nm while ethylene or an ethylene bridged samples are stable. Mechanism of UV initiated destruction of phenylene bridged materials is analyzed by using quantum chemical calculations. The presented results allow to conclude that the presence of long aliphatic and aromatic bridges makes OSG materials more sensitive to UV light