Characterization of ultra low-k SiOC(H) film deposited by plasma-enhanced chemical vapor deposition (PECVD)

Abstract

In this study, deposition of low-dielectric constant SiOC(H) films by conventional plasma-enhanced chemical vapor deposition (PECVD) were investigated through various characterization techniques. The results show that, with an increase in the plasma power density, the relative dielectric constant (k) of the deposited films decreases whereas the refractive index increases. This is mainly due to the incorporation of organic molecules with CH 3 group into the Si-OSi cage structure. It is as confirmed by FT-IR measurements in which the absorption peak at 1,129 cm -1 corresponding to Si-O-Si cage structure increases with power plasma density. Electrical characterization reveals that even after fast thermal annealing process, the leakage current density of the deposited films is in the order of 10 -11 A/cm at 1.5 MV/ cm. The reliability of the SiOC(H) film is also further characterized by using BTS test. © 2012 Kieeme. All rights reserved.