Large-area fabrication of stochastic nano-structures on polymer webs by ion- and plasma treatment

Self-organized nano-structures can be created on polymer surfaces by applying a plasma or ion treatment [1]. This technology may be used for anti-reflection (AR) applications in plastic optical devices, e.g. for aspheric lenses in mobile phone cameras. Compared to conventional AR-coatings, the nano-structures exhibit a large potential for reduction of cost and increase of optical performance. The technology described in [1] was developed in a batchcoater and successful used to achieve AR-properties to polymer sheets and optical devices. This paper describes the transfer of this technology from a batch coater to an in-linemachine for continuous surface treatment. A suited ion source to being installed in reel-to-reel equipment is chosen. The best properties for the described approach were observed by polymer surface treatment by a glow discharge created with a dual magnetron systemwith fully poisoned (oxidized) target surface. The processwas installed and optimized in a pilotscale reel-to-reel coatingmachine with a process width of 600 mm. Stochastic nano-structureswere created on PET, TAC and ETFE substrates. The relevant process parameters for plasma treatment are discussed. The process was transferred to industrial equipment with 2100 mm process width.