A Novel Pulsed Supply With Arc Handling and Leading Edge Control as Enabling Technology for High Power Pulsed Magnetron Sputtering (HPPMS)

摘要

Early high power pulsed magnetron sputtering (HPPMS) results are generating growing interest in the technique because it can create large numbers of both sputtered species and process gas ions. A significant flux of these ions to the substrate at low energy can result in dense equi-axed films, desirable for many applications. An experimental power supply was designed and built to investigate HPPMS. It can deliver peak powers up to 3 MW at pulse widths of 100 to 150 microseconds, up to 20 kW average power, at frequencies up to 500 Hz. Optical spectroscopy of the plasma shows ioniza-tion of the sputtered species. The amount of ionization depends on the peak power. HPPMS has been reported to deposit very thin carbon films with a measured density of 2.7 g/cm~3, quite high for sputtered carbon. The power supply has pulse leading edge control, and arc suppression capability, enabling HPPMS deposition of materials such as carbon and aluminum which are prone to arcing. With this pulsing supply the plasma goes directly from the glow to the highly ionized state without accessing the arc state. Pulse circuit and cabling considerations, electrical measurement techniques, electrical process waveforms, optical spectra, and process characteristics will be presented.