Is the silver paste bond used on both the anode and the cathode connections?
Generally the cathode is on the base side of the LED Chip. This is then silver paste bonded into the reflector cup. The top side of the chip in most LEDs is wire-bonded from the chip to the anode lead. On GaAlAs 660nm Red chips, the nature of the material is reversed. The anode is the base side of the chip. This side is silver paste bonded into the reflector cup. In this case it is the anode. Now there is a third kind of a chip. This is the InGaN using a sapphire substrate. In this case, the silver paste is applied to the cathode base side of the chip but there are cathode and anode connections on top of the chip as well. There are 2 wire bonds in this case, one cathode that is connected to the reflector cup and the anode that is connected to the anode lead. Do you have an LED lamp question? You can e-mail your LED lamp questions to our application engineers at: webmaster@ledtronics.com Founded in 1983, LEDtronics leads where others only follow when it comes to designing, manufacturing
