AVS 53rd International Symposium
    Plasma Science and Technology Wednesday Sessions
       Session PS2+TF-WeM

Paper PS2+TF-WeM4
Tantalum Oxy-nitride Film Deposition by Electron Cyclotron Resonance Plasma Sputtering for MIM Capacitor

Wednesday, November 15, 2006, 9:00 am, Room 2011

Session: Plasma Deposition
Presenter: T. Ono, Hirosaki University, Japan
Authors: T. Ono, Hirosaki University, Japan
H. Toyota, Hirosaki University, Japan
M. Shimada, NTT MI Labs, Japan
Y. Jin, NTT MI Labs, Japan
Correspondent: Click to Email
A high-k dielectric film is one of the key to realize high performance large scale integrated circuits (LSIs). The deposition characteristics of tantalum oxy-nitride (TaON) films have been investigated by using an electron cyclotron resonance (ECR) plasma sputtering without external substrate heating. A pure tantalum metal target was used as raw material supply combined with gases of oxygen and nitrogen. The electrical characteristics of the deposited films were examined by using MIM capacitor of ruthenium blanket electrodes and aluminum top pad electrodes. The electrical characteristics of the deposited films were changed from metallic conductive states to high-k dielectric states by the mixture ratio of oxygen and nitrogen. For the dielectric films, in high concentrations of oxygen gas, the deposited tantalum oxide (Ta@sub 2@O@sub 5@) films have a refractive index of 2.15 at 632.8 nm wavelength, high dielectric constant of 25, and high breakdown-strength of 5MV/cm. By controlling the oxygen gas concentrations in moderate low region, films of TaON have been stably obtained with the refractive indices of around 2.9 at 632.8 nm wavelength, higher dielectric constants of over 35 and breakdown-strengths of around 1MV/cm. In spite of low substrate temperature without external heating, high quality TaON films have successively obtained. The TaON films deposited by the ECR plasma sputtering can be applicable to the capacitor dielectrics and gate oxides for Si-LSIs, compound MIS-FETs, and the drive circuit devices for LCDs.