Counter Based Electrode Cleaning to Avoid Sparking Issue that Causes Delay (Speed Loss)

Abstract

Wire Bond is one of the most important processes in the IC manufacturing stage, this process aims to create an electrical connection between the die and the lead frame using a thin wire, one of the critical steps in this process is the Electronic Flame Off (EFO). Electrode Flame-Off (EFO) is a controlled process where the thin wire on the capillary (Tail) is heated using high current pulses that generate intense heat through the Torch Electrode. These pulses generate intense heat through the Torch Electrode, which melts the tip of the Tail. This melt form a small ball of molten metal called the Free Air Ball (FAB). The high current pulse applied to the wire causes the wire tip to melt and then solidify, creating a buildup. This buildup leads to spark faults/failures, which results in decreased UPH (units per hour) and reduced OEE (overall equipment effectiveness) due to high speed loss, the current cleaning method requires removing the Torch Electrode from the Nozzle, the Torch Electrode is only cleaned when there are severe sparking problems. When that happens, there's a lot of buildup on the Torch Electrode, which makes cleaning take longer. Sometimes, the buildup hardens so much that it can damage the Torch Electrode when it is removed. In such cases, the Torch Electrode needs to be replaced. The author used the PDCA approach method to test a cleaning method that was expected to be efficient. The author also monitored the methods to determine the best frequency. This led to the decision to clean without removing the Troch Electrode from the Nozzle follow the set time. By implementing this project, it is hoped that an efficient Torch Electrode cleaning method and proper frequency definition can prevent Spark problems.