WelcoTM LED131: Lead-free No-Clean Printing Paste​

A lead-free solder paste that promotes outstanding wetting and minimizes soldering defects. Suitable for LED flip-chip package of mini-LED display, lighting, and automotive.

The increased demand for better contrast and longer product lifespan in the display industry led to the introduction of backlighting modules. The challenge is the tiny size of soldering pads in these backlighting modules. It requires consistent application into the pads. ​

WelcoTM LED131 is a lead-free solder paste formulated with Heraeus proprietary WelcoTM powders. Its’ flux system is optimized explicitly for lead-free alloys, such as Sn/Ag/Cu. This formula provides superior performance on a variety of surface finishes and leaves behind a clear residue. The superfine unique WelcoTM powder technology excels in printing and soldering performance in tiny LED pads, that enables consistent printing even in tight particle size distribution.​

​WelcoTM LED131 Type 6 paste is available for 5*9mil and 4*8mil flip-chip LED die soldering.​

Key Features

  • Wide processing window, suitable for traditional die attach and die mass transfer application
  • Excellent printing performance for ultrafine pitch and long work life
  • Good shear strength for solder joint and high reliability
  • Superior wetting performance on fine pitch and self-align in reflow process
  • Light residue - perfect for optical application.
  • Low voids