"Closed field" magnetron (CFM) sputtering offers a flexible and high throughput deposition process for optical coatings
and thin films. CFM sputtering uses two or more different metal targets to deposit multilayers comprising a wide range
of dielectrics, metals and conductive oxides. Moreover, CFM provides a room temperature deposition process with high
ion current density, low bias voltage and reactive oxidation in the entire volume around the rotating substrate drum
carrier, thereby producing films over a large surface area at high deposition rate with excellent and reproducible optical
properties. Machines based on the Closed Field are scaleable to meet a range of batch and in-line size requirements.
Typically, thin film thickness control to <±1% is accomplished simply using time, although optical monitoring can be
used for more demanding applications. Fine layer thickness control and deposition of graded index layers is also
assisted with a specially designed rotating shutter mechanism. This paper presents data on optical properties for CFM
deposited optical coatings, including anti-reflection, thermal control filters, graded coatings, narrowband filters as well
as conductive transparent oxides such as indium tin oxide and carbide films. Benefits of the CFM sputter process are described.
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