High- Accuracy Die-Bonding Technology for LED Array

A die-bonding technology was developed and includes 1) high-accuracy, full cutting of a light-emitting diode (LED) array on a GaAsP substrate with a dicing saw; 2) screen printing of a B-stage curing, Ag-filled epoxy resin on an alumina ceramic snbstrate on which a thickfilm gold conductor is formed; 3) loading and fixing of the aforementioned ceramic substrate onto the die-bonder heater stage; and 4) die bonding by maintaining the spatial position of the LED array with five tools of the die bonder until the epoxy resin is thermally cured. The highly accurate positioning and stable conductivity of the die bond is ensured by reducing the dispersion of positional error between the LED array and ceramic substrate to within ± 10
\mu
m and providing stable ohmic contact characteristics between the LED array and ceramic substrate.