Basedongeneralplasmaenhancedchemicalvapordeposition(PECVD), a novel plasma set-up equipped with horizontal electronic field and perpendicular magnetic field is built in this study for a purpose of obtaining a high density plasma source. In order to characterize plasma parameters, optical emission spectroscopy (OES) was used to diagnose the electron temperature and electron density in plasma. The electron temperature calculated through Stark broadening function is in the range of 1.0–5.0 eV while the electron density is in the range of 5.0–10.0 􏰃 1015 cm−3. The electron density is three orders of magnitude higher than that in normal plasma. OES results also indicate that oxygen concentration pays an essential role both on the dissociation of Hexamethyldisiloxane (HMDSO) molecule for Si precursor and on oxidation reactions of fragments, which supplies the theoretical research of plasma chemical reaction mechanism.