AVS 53rd International Symposium
    Thin Film Tuesday Sessions
       Session TF-TuP

Paper TF-TuP24
Device-Quality SiO@sub 2@ Dielectric Film Formation using UV-light Excited High Purity Ozone and Organic Silicon Source at 200 @super o@C

Tuesday, November 14, 2006, 6:00 pm, Room 3rd Floor Lobby

Session: Thin Film Poster Session
Presenter: N. Kameda, Meidensha Corporation, Japan
Authors: N. Kameda, Meidensha Corporation, Japan
T. Nishiguchi, Meidensha Corporation, Japan
S. Saitoh, Meidensha Corporation, Japan
T. Noyori, Meidensha Corporation, Japan
Y. Morikawa, Meidensha Corporation, Japan
M. Kekura, Meidensha Corporation, Japan
H. Nonaka, National Institute of Advanced Industrial Science and Technology (AIST), Japan
S. Ichimura, National Institute of Advanced Industrial Science and Technology (AIST), Japan
Correspondent: Click to Email
It has been strongly required recently to deposit high quality silicon dioxide (SiO@sub 2@) films at lower than 400 @super o@C for the formation of the dielectric film of TFT on low-cost glass or plastic. Thermal CVD using organic silicon source gas and ozone gas O@sub 3@ with concentrations of some 10 vol.% is one of the candidates for the formation. However, insufficient chemical reaction of ozone with the silicon source gas at lower than 400 @super o@C is known to result in rapid decline of the deposition rate as well as the incorporation of impurities such as carbon or OH in the film, decaying the film properties as a dielectric film. The solution for this is to use excited oxygen atom O(1D) that is known to be chemically more reactive than O@sub 3@ to organic materials. We applied the process that irradiates an ultra-violet (UV) light (>210nm) in low pressure (~100 Pa) highly concentrated (>90vol.%) O@sub 3@ (HC-O@sub 3@) and hexamethyldisilazane (HMDS) mixture gas in order to make use of high chemical reactivity of O(1D) atom that is generated by photo-dissociation of O3 by UV light irradiation. To minimize the thermal decomposition of the HC- O@sub 3@ to O@sub 2@ as well as excess reaction of the HC- O@sub 3@ to HMDS gas before arriving at the process wafer, the temperature of the transfer tube of the gas mixture and a process chamber were fixed at room temperature. The dramatically increased deposition rate as well as temperature independent deposition rate between 200@super o@C and 300 @super o@C, at which almost no growth has been reported for low concentration ozone CVD, has been obtained. In addition, leakage current density through thus deposited film with the deposition rate of 10 nm/min at 200 @super o@C has been lower than 10@super -8@ A/cm@super 2@ when 2 MV/cm electric field is applied. The detailed results about the deposited film quality as well as the mechanism of the deposition process will be discussed.