Packaging technology for electronics devices has advanced rapidly in recent years driven by feature size reduction, new materials development, and increased demand on device functionality. The most fundamental among the advanced packaging technology is the use of wafer bumping and wafer-level chip scale packaging.

This paper introduces breakthrough technology that uses electron attachment (EA) to activate hydrogen at ambient pressure and at a starting temperature as low as 100°C. It offers major benefits for wafer bump reflow:

1) enhanced bump reflow quality by reducing flux induced solder voids and wafer contaminations

2) improved productivity by having in-line process capability, eliminating post wafer cleaning, and avoiding furnace down time cleaning

3) reduced cost of ownership due to eliminated costs associated with cleaning equipment, cleaning solutions, labor, and flux

4) improved safety by eliminating flux exposure and using a non-toxic and non-flammable gas mixture

5) reduced environmental issues by eliminating organic flux vapors and hazardous cleaning chemicals, and reducing water consumption required in post-process cleaning.