Abstract

Optics and MEMS is a powerful combination with many applications. In this talk I’ll focus on two projects in our group: cantilever based biosensor and thermo-mechanical infrared imaging using. Both systems show good examples of combining MEMS with optical readout to achieve high-sensitivity and parallel readout.

Label-free biosensing offer important advantages for point-of-care diagnostics due to its simplicity. We developed a biosensor platform technology platform where nickel-based MEMS cantilevers are placed in a disposable cartridge with no electrical connections. The reader unit contains an electromagnet for remote actuation, a laser for optical readout, and detectors and control electronics to track the phase and amplitude of multiple cantilevers near resonance. Initial applications we demonstrated are coagulation time measurements using serum and whole blood, and detection of hepatitis at low concentrations.

In the second part of the talk, I’ll describe our work on thermal imaging sensor where MEMS based pixels absorb thermal radiation and bend in response to heating. The detection is using a remote laser and grating interferometer integrated underneath each pixel, which offer excellent sensitivity. We exploited both CCD camera based readout and integrated CMOS readout. CMOS readout IC is post-processed to open through silicon via holes next to each pixel to allow laser light before integration with the MEMS detector array.