MONITOR IN LASER WIRE BONDER

摘要

PURPOSE: To provide a reflectance monitor for performing feedback control in a laser wire bonder by monitoring variation in the reflectance of a wire and processing the reflectance through feedback control for a laser being used in laser wire bonding. CONSTITUTION: An Nd:YAG laser 10 is employed for bonding a wire 12 to a pad 14 on a substrate 16. The monitor comprises a laser means 30 emitting low output laser energy having linearity common to a high output laser energy beam 10 and being reflected on the wire 12 during the bonding operation, means 48 for detecting the reflected low output laser energy and delivering a reflection signal proportional to the detected level and means 92 for controlling the high output laser energy beam depending on the reflection signal. According to the arrangement, laser processing can be controlled during laser wire bonding by utilizing variation in the reflectance of the wire 12 to be bonded.