Microwave operation of on-chip antenna embedded in WL-CSP [RFID applications]

An on-chip antenna for microwave operation is demonstrated. The application of wafer-level chip-scale package (WL-CSP) techniques such as dual Cu electroplating conductive layers, and thick resin layers separating the conductive layer more than 10 /spl mu/m from the Si substrate, allow on-chip integration. Details of the antenna fabrication process and performance are presented. Antenna performance achieved a maximum communication range between the on-chip antenna and a transmission module of over 400 mm at a transmission signal power of 300 mW. WL-CSP techniques realize real chip-scale long communication range radio frequency identification (RFID) tags.