Electroforming technology, adds superior aperture size consistency, geometry capability and printing characteristics, leading directly to reduced defect rates.
The stencil has proved to be very effective for printing solder paste on SMT boards that have fine pitch parts spread over a large area.
It also provides excellent print performance for applications with minature BGAs, ultrafine pitch QFPs and small chip components such as 0201’s.
Is the perfect enabling technology for new generation packaging such as wafer bumping applications.
- Smooth, trapezoidal sidewalls - maximise solder paste release
- Unsurpassed tensile strength and hardness - increased stencil life
- Nickel surface properties - low surface energy enhances solder paste release.
- Available in thickness - 25 micron to 300 micron in 2.5 micron increments
- Precise aperture sizes - Post Processing size compensation not required
The electroforming process
Stencils are formed by the migration of individual nickel atoms onto the surface of a conductive mandrel. The mandrel carries a negative, photoresist image of the aperture pattern.
The coating is polymerised by light exposure through a photo mask of the board pattern.
After developing, a negative image is created on the mandrel. Only the stencil aperture locations remain covered by the photoresist.
The nickel is then migrated onto the mandrel surface atom by atom. When the resulting foil has reached the required thickness, it is separated from the mandrel after removal of the remaining photoresist.
Electroformed stencils are available mesh mounted onto industry-standard frames or as foils for the Vector frame.