AVS 50th International Symposium
    Applied Surface Science Wednesday Sessions
       Session AS-WeM

Paper AS-WeM8
Investigation of PECVD TiO@sub 2@ on Silicon

Wednesday, November 5, 2003, 10:40 am, Room 324/325

Session: High-K Materials Interface Analysis
Presenter: P.R. McCurdy, Colorado State University
Authors: P.R. McCurdy, Colorado State University
L. Sturgess, Colorado State University
S. Kohli, Colorado State University
E.R. Fisher, Colorado State University
Correspondent: Click to Email
Continuous wave (CW) and equivalently powered, pulsed radio frequency plasmas were used to deposit thin films of titanium dioxide on to Si(100) substrates. In these experiments oxygen plasmas were created by feeding oxygen gas through the coil region, titanium (IV) isopropoxide was introduced downstream from the plasma region. These films have been characterized using XRD, XPS, SEM and AES. XRD showed that TiO2 films deposited at substrate temperatures ³350ºC are polycrystalline with an anatase structure, while at lower substrate temperatures the films were amorphous. Results show high quality films were produced with some carbon incorporation. Annealing these films in vacuum at 900 oC show the TiO2/Si interfacial region to be reduced to Ti2O3, while Si is oxidized to SiOx. Upon annealing at a 950oC further reduction of the TiO2 film was noted to include TiO. The 950oC film partially re-oxided upon exposure to atmosphere. XRD of annealed films showed no crystalline structure of these annealed films. SEM of the TiO2 film surfaces showed the as deposited films were smooth and structureless and remained so even when annealed at 850oC. Annealing at 950oC caused the surface to become very rough, resulting in the rupturing of the TiO2 surface thus exposing areas of the underlying Si/SiO2 substrate.