Wireless, RF & Smart Dust

We present a mm-sized, ultrasonically powered, lensless CMOS image sensor for wireless fluorescence microscopy. Access to real-time cellular-level information within the tissue can provide new insights for diagnosis and personalized treatment guidance across numerous medical conditions including cancer therapy. In cancer immunotherapy, for instance, where a priori identification of responders is challenging, real-time intratumoral information can aid early assessment of treatment response, identifying activation of the immune system leading to durable responses or rapid...

As RF MEMS technology evolves to shift towards UHF frequencies, the parasitics inherent in hybrid fabrication approaches become the performance bottleneck. This project aims to integrate metal MEMS resonators directly over CMOS circuitry to achieve fully integrated MEMS systems. Pursuant to this goal, this project proposes several designs for UHF MEMS bandpass filters, exploring how different CMOS-compatible metals can yield performance metrics—such as quality-factor (Q), temperature stability and frequency drift—that are comparable to those of standard polysilicon MEMS resonators....

A self-healing MEMS RF switch, which utilizes liquid gallium contacts to take the place of the traditional metal-to-metal hard contacts, is proposed in this project. Electrostatic actuation is used to drive a silicon nitride diaphragm with upper electrodes. When the diaphragm is pulled down by the electrostatic force, small droplets of liquid gallium work as an interface between the upper and lower electrodes. The loss of the gallium droplets can be avoided due to the unwettability of the material surrounding the contact areas. In this project, hermit package and 1A DC current...