Preface to Special Topic: Reactive high power impulse magnetron sputtering

摘要

Magnetron sputtering is a widely used physical vapor deposition technique that has been applied successfully by various industries for the deposition of thin films and coatings for over four decades. The high power impulse magnetron sputtering (HiPIMS) discharge is a recent addition to plasma-based sputtering. In HiPIMS, high power is applied to the magnetron target in unipolar pulses at a low duty cycle and low repetition frequency while keeping the average power about two orders of magnitude lower than the peak power. This high discharge power leads to the generation of a very high density plasma and thus a high ionization fraction of sputtered atoms. Thus, for the sputtered material, the ion flux is larger than the neutral flux and HiPIMS can be referred to as ionized physical vapor deposition. Ionized sputtered flux allows for controlled ion bombardment of the growing film by the acceleration of the sputtered material across the plasma sheath created by a negative bias applied to the substrate.