US Patent 6,819,004 covers an epoxy-fluxing technology that enables no-flow underfill. The methods and materials covered within the patent permit attachment of flip chips to electronics assemblies sans underfill adhesive processes.
Kester is offering licenses for the patented technology.
In a press release, Kester said the novel technology halves the number of process steps by eliminating a steps for flux residue cleaning, capillary underfill lengthy dispensing and capillary underfill post-curing.
Central to the technology is the use of epoxy that acts as a flux during the initial soldering and then acts as an adhesive during encapsulation. The soldering or fluxing operation and encapsulation have been combined into a single stage. The patent for this technology not only covers the material but also the application such that the flip chips could be attached to the substrate simultaneously with the remainder of the surface mounted devices, Kester said.
"This patent reflects Kester's dedication to continuous innovation, which is our competitive anchor. We are very pleased that Kester's invention has been recognized by the United States Patent and Trademark Office," said Brian Deram, vice president of research and development.
Kester is actively marketing several formulas that are covered by this newly issued patent under its trademarked "SE-CURE" line. Users, the company said, are indemnified from the method of use claims covered by this patent. Licensing opportunities are available, Kester said.