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Soldermask Availability
A variety of soldermasks have been selected to fill the needs of our customers. The following is a description of the soldermasks currently available. The need for closer tolerances has driven the implementation of photo-imageable soldermasks.
Liquid Photo-Imageable (LPISM) Soldermasks
Enthone DSR 3241 ‡ is applied using the flood screen coating process, while PROBIMER 52Mâ is applied via the curtain coating process. Enthone DSR 3241 has a green semi matte finish. Enthone DSR 3241soldermask has improved resolution capability, meaning that it can hold a finer feature, such as a “dam” between SMT pads. Liquid Photo-imageable soldermasks are considered to be soldermasks of choice for most circuit board product due to their high resolution, excellent electrical properties and compatibility with surface mount technology.
Hole “tenting” is available through the via-cap process in which PC401â, a thermally cured epoxy, is screened over the holes to be tented, after liquid photo-imageable soldermask is applied. This is an advantage for vacuum applications after assembly.