Die Picking • Die can be directly picked from the wafer after the wafer sawing process. • Die bonder are often equipped with ejector needle system to push against the backside of the wafer to eject the die. • Computer controller vacuum pick-up tools are used to lift the dies
Epoxy Dispensing • Die attach epoxy is dispensed in controlled volume by dispenser to the substrate • The viscosity of the epoxy has to be controlled. • The location of the dispensing is controlled computer with vision control
Die Placing • The die pick-up arm of the die attach machine will send the die to the appropriate position and load the die on the substrate. • Die bonding pressure has to be controlled. • The substrate may be heated to facilitate partial curing of the epoxy die attach.
Epoxy Curing • The die bonded substrate may need to send for curing in ovens to stabilize the polymer. • There are fast curing epoxy and also UV cured epoxy to facilitate the process.