Abstract

The metal of the desired oxide thin film is molten in an electron beam evaporator (6-10 kW power) at below 10⁻⁶ mbar. After admitting the reactive gas (O₂) into the coating chamber, a low-voltage, high-current (50-80 V, 40-100 A) plasma arc burns into the melt which acts as the anode for the arc.¹ A hot hollow-cathode source mounted at the lower viewport of a standard 32″ box-coater delivers the arc at an Argon pressure of about 1 mbar. A 1 mm diameter orifice serves as differential pressure stage.

© 1988 Optical Society of America