Paper SE+PS-TuA12
Correlation of Microstructure of Deposited Thin Films with Discharge Characteristics by Modulated Pulsed Power Magnetron Sputtering (MPPMS)
Pure Cu thin films and TiAlSiN nanocomposite thin films are deposited in a closed field unbalanced magnetron sputtering system using the modulated pulsed power magnetron sputtering (MPPMS), in order to understand the correlation of the microstructure and texture of deposited thin films with the discharge characteristics by MPPMS. The discharge processes at different pressures on the metallic targets are numerically modeled with considering the loss of electrons by cross-B diffusion. With increasing the pressure from 0.1 to 0.7 Pa, both the ion bombardment energy and substrate temperature which are estimated by the modeled plasma parameters decrease, corresponding to the observed transition of the deposited Cu thin films from a void free structure with a wide distribution of grain size into an underdense structure with a fine fiber texture in the extended structure zone diagram. The TiAlSiN thin films are deposited at the ratio of the nitrogen flow rate to the total gas flow rate (fN2) ranging from 0 to 40%. An optimized nanocomposite structure of nc-TiAlN/a-Si3N4 is formed with the 5–10 nm TiAlN nanocrystallites embedded in the 2–3 nm amorphous Si3N4 matrix. Further increasing fN2up to 40%, the grain size of nanocrystallites increase to 10–20 nm with the gradually precipitation of AlN phase, albeit the composition keeps constant. With increasing the partial pressure, the increased ion bombardment energy and substrate temperature are believed to be responsible for the complete phase separation of the nc-TiAlN/a-Si3N4 nanocomposite thin films.