Metal Embedded Micro Sensors for Manufcaturing Applications

A novel batch production of metal embedded micro sensor units was realized by transferring thin film sensors from silicon wafers directly into nickel substrates through standard microfabrication and electroplating techniques. Ultrasonic metal welding (USMW) was used to integrate nickel embedded thin film thermocouple (TFTC) units into copper workpieces. The embedded TFTCs successfully survived the welding tests, validating that USMW is a viable method to integrate micro sensors to metallic tool materials. Moreover, the embedded micro sensors were also able to measure the transient temperature in situ at 50 mum directly beneath the welding interface during welding. Metal embedded micro sensors yield great potential to improve fundamental understanding of numerous manufacturing processes by providing in-situ sensing data with high spatial and temporal resolution at critical locations.