Rugged high speed paste from Heraeus

Soldering & Surface Mount Technology

ISSN: 0954-0911

Article publication date: 1 August 2000




(2000), "Rugged high speed paste from Heraeus", Soldering & Surface Mount Technology, Vol. 12 No. 2.



Emerald Group Publishing Limited

Copyright © 2000, MCB UP Limited

Rugged high speed paste from Heraeus

Keywords Heraeus Materials, Solder paste

The new Heraeus F816 series of solder pastes is a completely balanced, high speed engineering formula designed to meet the everyday printing challenges of even the most demanding production environments and PCBs.

The rheology of the F816 series has been optimised to offer an excellent print resolution and very high adhesion. This allows totally consistent high speed printing results to be achieved at laboratory proven speeds of up to 150mm/s. The rheology of the F816 Series is also fully ICT-friendly to allow test probes to penetrate and make reliable electrical contact with component pads.

Even on fine-pitch stencils, the F816 pastes will, regardless of print speed, separate out cleanly from narrow apertures without blocking. In addition, F816 series high green strength and excellent wetting capabilities mean that the pastes are particularly suited to printers with high accelerations and decelerations. They are also ideal for applications where difficult-to-solder surfaces have to be joined; including increasingly popular Cu+OSP protected board surfaces.

The Heraeus F816 family has also been engineered to offer very low slumping characteristics to avoid bridging, while an extended stencil life means the pastes will perform reliably over extended periods of time without drying out. This means any F816 paste will deliver excellent first print results even after a production pause (for example, a factory lunch break). The pastes can also be used in printers that exploit temperature control units (with very strong ventilation).

Although the F816 series is completely suitable for inert soldering under nitrogen, it also offers perfect print results in air and is insensitive to humidity levels while displaying zero tendency to create solder balling on chip resistors and capacitors.

The new Heraeus F816 solder paste series is available in an activation level to suit difficult-to-solder surfaces, which means that variations in pad and component solderability can be tolerated without a negative effect on yields.

Despite the F816 series' high activation, the SIR of its flux residues is exceptionally high and remains stable under even the harshest conditions (far exceeding the requirements of J-STD-004 or Bellcore standards) such as 85°C/85 percent RH after 21 days with a 100V applied DC bias and combined 0.4mm pitch.

For further information please contact: Jim Greig, Heraeus Materials Ltd, 1 Craven Court, Canada Road, Byfleet, Weybridge, Surrey KT14 7JL, UK. Tel: +44 (0) 1932 349 306; Fax: +44 (0)1932 347904; E-mail:

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