FCTA Mexico manufactures electroformed nickel stencils to offer superior paste release as industry standard board designs demand smaller apertures and pitch. Electroformed stencil aperture walls are smooth (mirror-like), providing less surface area for solder paste to cling to. Instead of laser cutting apertures, nickel is formed around a photoresist template of apertures that matches board designs. Electroforming also allows quick turnaround times for jobs with large aperture counts.
Advantages of Electroform Stencils:
Quick turnaround for jobs with large aperture count
Smooth aperture walls, good paste release
Thickness can be specified in 0.0001” increments
Electroform foil provides higher paste transfer efficiency than uncoated laser cut stencils
Nickel formed foils that are laser cut offer better paste release than laser cut stainless foils
Electroform stencils have higher tensile strength and hardness than stainless steel stencils
Electroformed foils can be produced in non-standard thicknesses
Thickness Tolerance Over Area:
Center to Center Aperture Tolerance:
Trapezoidal Aperture Walls:
1mil – 7mil
+/- 0.0004 over 10”
10×10″ area: within 0.001″ of original
Taper is approx. 0.1 mils [0.0001″] per side per mil of foil thickness. (E.g.) 5 mils thick foil would have ~ 0.5 mils taper per side
How does electroforming work?
#1) Resist on mandrel is imaged with a master photoplot.
#2) Undeveloped resist is stripped off, leaving pillars of developed resist.
#3) Once immersed in the nickel bath, the nickel atoms follow the electrical current and are deposited onto the mandrel.
#4) After removing from the mandrel and remaining resist, you are left with a nickel stencil.