IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Dielectrics Monday Sessions
       Session DI2-MoP

Paper DI2-MoP2
Characterization of Plasma-CVD Grown Low-k Porous Silica Films using Positron-annihilation Lifetime Spectroscopy

Monday, October 29, 2001, 5:30 pm, Room 134/135

Session: Low K Dielectrics Poster Session
Presenter: T. Ohdaira, National Institute of Advanced Industrial Technology (AIST), Japan
Authors: T. Ohdaira, National Institute of Advanced Industrial Technology (AIST), Japan
R. Suzuki, National Institute of Advanced Industrial Technology (AIST), Japan
Y. Shioya, Semiconductor Process Laboratory Co., Ltd., Japan
T. Ishimaru, Canon Sales Co. Inc., Japan
Correspondent: Click to Email
Positron-annihilation lifetime spectroscopy was used to determine the pore size distributions in low-k porous silica films deposited by plasma-enhanced chemical vapor deposition (PE-CVD) with source gases of hexamethyldisiloxane (HMDSO) and nitrous oxide (N@sub 2@O). In PE-CVD, the porosity of the film can be controlled by the deposition conditions, e.g. the pressures and flow rates of the source gases. In the present study, several kinds of porous films with k values ranging from 2.6 to 3.2 were prepared. The positron-annihilation lifetimes at selected depths in the porous films (500 nm thick) were measured by using a mono-energetic pulsed positron beam (0.5 keV - 20 keV). The obtained results show that the pores with average volumes of 0.3 - 1.1 nm@super 3@ are introduced in the films, and that the pore size strongly depends on the deposition conditions. The correlation between the pore size and the dielectric constant will be discussed.