The effects of UV curing on silicon oxycarbide films

Abstract

Changes in the configuration and properties of a commercial silicon oxycarbide (SiOC) films are examined as a function of substrate temperature after UV curing. The treatment results in a chemical configuration rearrangement in which the Si–O stretching and Si–C bending increase. A direct consequence of the configuration and structural evolution is a change in the electrical properties. A correlation is made between configuration and structure changes in the treatment and the resulting electrical properties. Fourier transform infrared spectroscopy was used to quantify the increased Si–O and Si–C and reduced Si–H as a result of increased treated substrate temperature. As a consequence, chemical and configuration changes affect the electrical properties of SiOC films after treatment. The dielectric constant and leakage current density were determined by the metal insulator silicon method. High substrate temperature was shown to greatly improve the dielectric constant and leakage current. A high substrate temperature contributes to the formation of a low polarity structure of O1/2–Si(CH3) in the treatment process, which makes the dielectric constant recover. It also helps eliminate the dangling bond to reduce the leakage current density of the SiOC films. The treatment time does not affect the final configuration of SiOC films. As treatment time increases, dielectric constant and leakage current increases and becomes saturated.