New developments in magnetron sputter processes for precision optics

Reactive magnetron sputtering processes have gained considerable interest for the production of precision optical coatings. Pulsed sputtering techniques allow the deposition of high quality optical materials at high deposition rates. However, under high throughput conditions and with tight spectral tolerances, process stabilization has to be included in the fabrication process. Normally, pulsed magnetron sputter techniques are typically characterized by a low ionization. Very recently, ionized magnetron sputtering techniques are under investigation, where either the reactive gas or the metallic sputtered particles are highly ionized. Plasma assisted reactive magnetron sputtering ("PARMS") using an additional plasma source or the high pulse power magnetron sputtering ("HiPIMS" or "HPPMS") can be applied therefore. The present paper gives results of film properties of optical materials obtained with these ionized magnetron sputtering techniques and discusses potentials of the techniques for the use with precision optics.