AVS 54th International Symposium | |
Plasma Science and Technology | Tuesday Sessions |
Session PS1-TuA |
Session: | Plasma Etching for Advanced Interconnects II |
Presenter: | J. Bao, The University of Texas at Austin |
Authors: | J. Bao, The University of Texas at Austin H. Shi, The University of Texas at Austin H. Huang, The University of Texas at Austin J. Liu, The University of Texas at Austin P.S. Ho, The University of Texas at Austin E. Paek, The University of Texas at Austin G.S. Hwang, The University of Texas at Austin |
Correspondent: | Click to Email |
Carbon Doped Oxide (CDO) low k films were treated by downstream O2 plasma. The effects of O2 plasma on blanket and patterned low k dielectric surfaces were studied by in-situ angle resolved X-ray photoelectron spectroscopy (ARXPS) and Fourier transform infrared spectroscopy (FTIR). The reaction byproducts were analyzed by residual gas analyzer. Roles of ions and radicals in the plasma to cause carbon depletion were investigated using a plasma source that was capable of separating ions from plasma beam. Energetic ions in oxygen plasma contributed much to the loss of film hydrophobicity and dielectric constant through the formation of C=O and Si-OH. Coupled with RGA analysis, three possible reaction paths leading to carbon depletion were proposed. Effects of ions and radicals on blanket low k films at different tilt angles (00 to 900) were analyzed. Finally, O2 plasma damage to patterned CDO film was studied by XPS and SEM. And the damage behavior was simulated with Monte Carlo method. It was found that the charging potential distribution induced by plasma was important in determining low k film carbon loss. The charging potential distribution was mainly related to the geometry of low k trench structures.