Posted 11/02/15 by Ravi M. Bhatkal, Ph.D.
LED chip-on-board applications (COB) typically involve assembling an LED die stack directly on to a substrate such as Metal Core PCB (MCPCB), FR4 etc.
A variety of die attach materials, including solder, conductive adhesive, or sintered materials can be used to bond the LEDs to the substrate, depending on the specific requirements, and the tradeoffs involved.