AVS 52nd International Symposium
    Thin Films Monday Sessions
       Session TF-MoP

Paper TF-MoP15
Low Temperature Formation of High-Quality SiO@sub 2@ Thin Film using UV Light-Excited Ozone

Monday, October 31, 2005, 5:00 pm, Room Exhibit Hall C&D

Session: Aspects of Thin Films Poster Session
Presenter: A. Tosaka, National Institute of Advanced Industrial Science and Technology, Japan
Authors: A. Tosaka, National Institute of Advanced Industrial Science and Technology, Japan
T. Nishiguchi, Meidensha Corporation, Japan
H. Nonaka, National Institute of Advanced Industrial Science and Technology, Japan
S. Ichimura, National Institute of Advanced Industrial Science and Technology, Japan
Correspondent: Click to Email
Fabrication of high quality SiO@sub 2@ film at low temperature is required for a gate dielectric film in thin film transistor for future display devices. We have developed an oxidation system using highly concentrated ozone excited by KrF laser light (248 nm) since it is expected that ozone molecules exposed to 248 nm light readily decompose into excited oxygen atoms, O(@super 1@D), and oxygen molecules. It was revealed that the UV excited ozone results in SiO2 film growth more than 3.6 nm thickness at 70 °C within 10 min., sufficiently thick as a barrier oxide. The growth rate behavior shows that there are two oxidation mechanisms and the activation energy is almost zero (0 to 5 min.) and 0.14 eV (after 5 min.), respectively. The low activation energy is due to the reaction between highly-reactive O(@super 1@D) and the silicon surface layers whose electric state is UV-excited. The current density (J)-electrostatic field (E) characteristics of the SiO@sub 2@ film show the ideal tunneling current properties, indicating that the KrF laser light irradiation does not induce defects in the film. Details reaction mechanism of O(@super 1@D) with silicon in terms of the density of excited oxygen atoms will be also discussed.