Emerald Group Publishing Limited
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Alpha launches electroformed stencils
Keywords Alpha Metals, Stencils
Alpha Metals has installed manufacturing facilities in its Rotec plant in Turnhout, Belgium, to produce highly accurate electroformed stencils. Alpha high precision, electroformed stencils are manufactured from extra hard nickel (approx 600VH) using state-of-the-art equipment, for assemblers working with ultra fine pitch tolerances in surface mount and microelectronics applications, and for high volume assemblers.
These electroformed stencils offer exceptional print limits (>251µm aperture size / 150µm stencil), and thanks to perfect flatness and sharp apertures allow high precision printing without under stencil bleed. The stencils are designed to deliver exceptional paste volume control resulting in high yields, with low cleaning requirements resulting from the stencil to pad gasketting effect, caused by a smooth, "mirror-like" board side surface. Alpha's unique finish techniques ensure a squeegee side surface texture which promotes ideal grip and roll for solder paste printing.
The manufacturing facility has been purpose built to include the latest electroforming technology - including clean room operating conditions with air purity levels of class 1,000ppm, helping eliminate particle contamination of stencil masks. This, together with high resolution (10,000dpi) photoplotters and collimated light exposure units (which overcome the random light patterns typical of normal UV exposure techniques affecting stencil accuracy), provide a precise transfer environment for customers' direct CAD data to the electroformed stencil manufacturing process.
The stencils have a nominal tolerance of ±3µm, with positional tolerance of ±0.1 percent, and the electroformed foils are suitable for use mounted in standard frames or with proprietary tensioning systems such as Alpha Tetra.
Further information is available from: Paul Davis, Alpha Metals. Tel: +44 (0)20 8665 6666.