Hexamethyldisilazane (HMDS) is one of the cost-effective and stable compounds used for the synthesis of thin films for numerous applications such as silicon nitride thin film deposition. In order to deposit thin films from HMDS, plasma enhanced chemical vapor deposition (PECVD) is commonly used, because the plasma can offer enough energy to effectively decompose the HMDS and leads to the formation of films. In addition, with HMDS, various gases have been added to the plasma to modulate the plasma characteristics. In this study, the influence of the addition of nitrogen in an atmospheric pressure Ar/HMDS plasma was investigated. Optical emission spectroscopy measurements provided valuable insights into the characteristics of the plasma under different nitrogen gas flow rates and the importance of nitrogen as a deposition parameter was discussed. Consequently, the introduction of nitrogen in the Ar/HMDS plasma resulted in the decrease of various temperatures such as excitation, vibrational and rotational temperatures, which significantly changed the composition of reactive species in the plasma.

Keywords: Hexamethyldisilazane, plasma enhanced chemical vapor deposition, nitrogen plasma, synthetic spectra, optical emission spectroscopy