Lapping film needs “stiction” PSA to the rescue!

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We have over 60 years of combined technical support experience with interferometry, film, fiber cleaners, scopes, and the polishing process. We work closely with our customers to develop and resolve process control issues. Our support includes application development samples or equipment when available.

Additionally, We offer videos and “how-to” charts throughout the site. We have experience with JIT and understand shipping requirements and reliable delivery consistency. The phenomenon of two such surfaces being adhered together in this manner is also called stiction. Stiction may be related to hydrogen bonding or residual contamination.

Stiction is static friction. Friction is the force resisting the relative motion of solid surfaces, fluid layers, and material elements sliding against each other. Friction helps prevent slippage while polishing.

Consider our Quality PSA-backed film. The main reasons are how the assembly manufacturer secures the lapping film to the polishing pad or plate. The goal is to avoid slippage and ensure the film is not slipping on the pad or plate instead of polishing the connector’s tip. The bottom layer of lapping film usually is a mylar substrate. A PSA-backed film that has the adhesive on the backside of the mylar. It is supplied with a paper backing that the user peels off to expose the adhesive layer. This is then pressed onto the polishing plate to attach the film securely, preventing slippage. The adhesive backing is the only physical difference between PSA and non-PSA film.

Generally, PSA-backed film is most useful with a polishing process that uses a glass plate. Non-PSA film can be used effectively with a process that uses a rubber polishing pad. Typically, glass plates are used for flat tips, such as fiber array-type connectors. Rubber pads are used to get a rounded or radiused tip. Hence, most processes for making multi-fiber assemblies use PSA film. The non-PSA films work well with single-fiber polishing.

Polishing the fiber is the last and most critical step in the connector assembly process. Polishing finalizes the connector end-face and cleans the surface, which has a direct impact on such optical performance parameters as insertion loss, return loss, and bit-error rate for overall network performance.