With the new DS Laser, Mühlbauer has developed a particularly gentle die handling method. It works with a laser shot to release the die from the wafer instead of a mechanical die release system. Thus, the chip is exposed to less mechanical stress during the lift process in comparison to the standard die ejector needles, for example. The good dies are picked up from the wafer, flipped by 180°and placed face down into the carrier tape.
The new system assumes the usage of a wafer on glass with a thermal release wafer foil. Wafer frame and wafer expansion are no longer required. This is applicable for standard as well as thin die down to 30µm thickness and even less. The mayor benefit of the wafer on glass is the ability to test the singulated dies on the wafer level to avoid chip-outs that occur during the sawing process.
Due to the rigid substrate of the glass wafer, the testing of the whole wafer can be proceeded at once during the process of wafer probing.Therefore, the new DS Laser is an essential component of a new WLCSP process flow.
Different automatic optical inspection features such as top and bottom as well as SIDEWALL inspection in combination with an automatic replacement function of bad dies in the tape pocket guarantee optimal output yield with 100% optical inspection of all dies.
The carrier tape index system includes input/output spooler for carrier and cover tape as well as a sealing station for cold or hot sealing. With an optional second input/output spooler and index track, the material exchange, sealing test times and leader/trailer time can be reduced, based on the continuous sorting into the second lane as well as multi bin process is able to place two bins in one run into two different tapes. With dual indexer capability the DS Laser will assure you highest daily net output due to time saving in terms of reel change, time lost for leader and trailer action.
In addition, the DS Laser includes FOUP handling and comes with a robotic arm that takes wafer handling to a new level. The careful handling process is subject to less stress during the transportation from the FOUP magazine to the wafer table and therefore reduces the risk of a wafer damage.
The system has a throughput of up to 12,000 UPH for flip chip including vision inspection.