Aerospace News

Henkel’s Multicore LF730 Raises the Bar on Lead-Free Solder Paste Performance

12/7/2009 12:00:00 AM

Building on its successful lead-free solder products portfolio, Henkel has developed Multicore LF730, a Pb-free solder paste born from the company’s unyielding innovation commitment and arguably setting the benchmark for lead-free paste performance.

With the company’s Multicore DAP Plus Type 4 solder powder at its foundation and an innovative flux medium that allows for greater process latitude, Multicore LF730 enables robust high-speed printing even for extremely fine parts, successfully printing thorough apertures as small as 160 microns in diameter and stencils as thin as 80 microns. The unique approach to particle size distribution of the new Henkel paste delivers more solder per aperture, but with much less risk of aperture clogging as compared to traditional Type 4 pastes. The improved packing efficiency ensures greater volume through the aperture and consistent volume release of over 90%.

“This latest material design has pushed innovative solder paste formulation to a new level,” enthusiastically explains Steve Dowds, Henkel Global Product Manager for Solder Products. “Not only does it address the challenges posed by highly miniaturized devices, but Multicore LF730 also provides assembly specialists with the manufacturing latitude they need to cope with often uncontrollable conditions such as variations in PCB surface finishes.”

Among its many benefits, Multicore LF730 provides excellent wetting ability to a wide range of surface finishes, which is extremely important to customers as variability in PCB surface finish quality can often present production challenges, particularly with solder paste wetting. The adaptability of the material is also evidenced through its thermal stability, as Multicore LF730 has shown consistent performance even in environments as warm as 30°C at 84% relative humidity (RH), so any degradation to material integrity due to environmental changes is unlikely.

Other advantages of Multicore LF730 include excellent open and abandon times with outstanding results after two to three hours even on the smallest apertures (225 microns), standard refrigeration storage, a six-month shelf life and good hot slump resistance, printing very narrow geometries without any bridging. Coalescence of the material is also superb, resulting in a solder joint with a remarkably smooth, shiny finish.

“Moving to smaller geometries requires the use of much finer solder powder, which means more surface area for a given weight of metal and thus more oxides. In the past, this meant a smaller reflow process window,” says Dowds. “Multicore LF730 brings to the industry the benefits of Type 4 printability with the excellent reflow capability you would normally see with a conventional Type 3 powder.”