1. Recommendations for Processing with MLS Copper
Process Station
Recommendations
Remark
Reduce Handling
No Pre-oven bake
RTF foil is more
susceptible to handling
damage to the matte
profile & contaminations.
Pre-clean
Micro-etch is not required
Use acid for pre-cleaning,
followed by a neutral to
slightly caustic rinse.
Complete drying
Matte surface has
already rough.
Photo Resists
Apply resists immediately
after pre-clean
Owing to better matte surface
of RTF, it may need to slower
down the feed rate, increase
temperature or pressure.

2. Recommendations for Processing with MLS Copper
Process Station
Recommendations
Remark
Expose Time
(Imaging)
Per shinning foil standard
Developing
Etching
Similar to shinny foil, there
is a chance to increase the
line speed
RTF foil profile at PP
side is lower
AOI
More compatible to laser
Technology
Latest reflective technology
is also applicable to RTF,
copper surface need to
be cleaned and no oxidation.
Substrate reflective
Copper reflective is
more sensitive to
surface cleanliness.
Oxide Treatment
Per shinny foil standard