Effect of HMDSO Addition on Discharge Characteristics of Atmospheric Pressure Plasma Jet Array in Argon

Atmospheric pressure plasma jet array is suitable for surface modification of large-area complicated material. To satisfy the needs of large-area plasma sources for material surface hydrophobic treatment, an atmospheric-pressure 1D Ar plasma jet array was accomplished and hexamethyldisiloxane (HMDSO) was added into its working gas to acquire plasma jet array containing hydrophobic containments. Electrical and optical methods were used to diagnose the discharge characteristic of jet array. Effects of applied voltage magnitude and content of HMDSO on discharge uniformity, discharge power, transported charge and main active particles were studied for optimizing the working condition of APPJ array in Ar and providing reference for hydrophobic modification by jet array. Results show that, as the content of HMDSO increases, the magnitude of discharge pulse current, the number of pulse current in each half cycle, discharge power, and transported charge are decreased, and the repulsion and coupling effect are restrained and the discharge uniformity is strengthened. Spectral intensities of main particles generated by discharge decrease as the content of HMDSO are increased, while the spectral intensity of silicon is increased before its descent. The maximal peak of silicon intensity exists when the content is 0.02% and plasma jet array fed by Ar/HMDSO working on this condition can be applied in hydrophobic material surface modification to achieve favorable effect.