NSF Award
2302182
This research is to explore various approaches for a single-chip detector that (1) can record semiconductor-chip-package tampering activity without the need of a battery, (2) can be placed inside semiconductor chip packages through a nozzle-less droplet ejector, and (3) can be wirelessly interrogated without need to open up the semiconductor package. The project’s novelties are (1) the integration of a pyroelectric energy converter, a GHz resonator, an acceleration switch and an on-chip antenna, all on a single chip at a low cost and (2) a submillimeter-sized, battery-less, tamper detector chip that can be placed inside a semiconductor package through a droplet ejector and that can be wirelessly interrogated (for any recorded tampering activity) from the outside of the semiconductor package. The project's broader significance and importance are the foundational technology for individualized detection and recording of tampering activities, without needing an electrical power source such as the battery, and for the recorded event to be wirelessly interrogated, particularly to ensure the authenticity of semiconductor chips. Also, the proposed study of droplet-ejector-based chip packaging will likely open up a new packaging technology for semiconductor chips, particularly for chips whose lateral dimensions are too small for robotic pick-and-placement. Thus, the research will impact the semiconductor industry the foremost, but will also likely help many other industries needing to detect activities involving temperature rise and mechanical banging without battery. The proposed passive resonator will also be broadly applied to battery-less, passive security and identification such as radio frequency identification (RFID).<br/><br/>A single-chip semiconductor-tamper detector will be based on a pyroelectric energy converter (PEC) for generating a voltage and charge to break an RFID tag based on High-overtone Bulk Acoustic Resonator (HBAR) from heat associated with the tamper activity. A MEMS (microelectromechanical systems) acceleration switch will be designed to make an electrical connection between the PEC and the tag when mechanical shocks are applied to semiconductor chips on a printed circuit board (PCB), as a part of a tampering activity to detach semiconductor chips from PCB, so that the voltage and charge of the PEC due to the heat from de-soldering process may electrically break the tag. As the tampering activity involves banging PCBs against hard objects after a de-soldering process, a normally-off MEMS switch will be designed as an acceleration or vibration sensor to detect the banging. Counterfeiters may have options to scavenge IC chips with other methods than the method covered by the proposed tamper detector, but at no avail or at too high costs. The project will show the feasibility of a submillimeter-sized, battery-less and wireless, tamper detecting chip that can be mounted inside a semiconductor package through a nozzle-less droplet ejector. The proposed study will pave foundational technology for a paradigm-shifting concept of individualized detection and recording of tampering activities to ensure authenticity of semiconductor chips. The proposed transducers will likely impact wireless sensor network, energy harvesting, etc., and thus, the research will greatly impact many industries including RFID and wireless sensor industries in addition to semiconductor industry.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
