The Hydrogen Heat Treatment Effect on Electrical and Structural Properties of a-SiOC:H as Low-k Thin Films
Various annealing conditions after film deposition have a great effect on electrical and structural properties of low-k films. In this work, we studied hydrogen atmosphere heat treatment effect on low-k films. After the room temperature deposition of a-SiOC:H low-k films following post-deposition-annealing (PDA) for 30 min. at 450°C in an N2 ambient, final annealing was performed for 30 min. at 400°C in an N2, a forming gas 1 (5% H2 + 95% N2), and a forming gas 2 (10% H2 + 90% N2) ambient. The flat band voltage was shifted toward the ideal value of 0.61V after two forming gas anneals, but it increased k values of the films. It was ascribed that hydrogen effectively substitutes defect sites or structural imperfections of low-k films and makes the film more hydrophilic. The FT-IR, XPS analyses and the contact angle measurement supported our conclusion.
Byung Tae Ahn, Hyeongtag Jeon, Bo Young Hur, Kibae Kim and Jong Wan Park
J. Y. Heo and H. J. Kim, "The Hydrogen Heat Treatment Effect on Electrical and Structural Properties of a-SiOC:H as Low-k Thin Films", Solid State Phenomena, Vols. 124-126, pp. 323-326, 2007