Dielectric properties of CVD grown SiON thin films on Si for MOS microelectronic devices

The bulk properties of SiON films grown on n-Si substrates by CVD are examined by means of electrical measurements and Rutherford backscattering spectroscopy (RBS). The main aim of this project was to investigate the performance of the films in order to test their suitability for the construction of CMOS devices with SiON being the gate insulator. The CVD technique was used to produce the films and subsequent metallization leads to the creation of MOS devices. Rutherford backscattering spectroscopy (RBS) was used to verify the film bulk properties. Electrical measurements including current-voltage, capacitance-conductance-voltage (C-G-V) measurements and admittance spectroscopy were performed allowing determination of the bulk trapped charges and the dielectric constant of the films. These charges were calculated to have values between 0.76 nCb and 2.54 nCb, while the dielectric constant of the films was found to be quite high, with values greater than 5 and as high as 34. The RBS concluded that the films were uniform, and the nitrogen concentration was not higher than 10%.