Indium Phosphide MEMS Cantilever Waveguides with Integrated Readout for Chemical Sensing
Indium Phosphide MEMS Cantilever Waveguides with Integrated Readout for Chemical Sensing
Files
Publication or External Link
Date
2007-11-26
Authors
Siwak, Nathan Paul
Advisor
Ghodssi, Reza
Citation
DRUM DOI
Abstract
This thesis presents the development towards an integrated, monolithic, micro-electro-mechanical system (MEMS) cantilever waveguide resonator chemical sensor using the III-V semiconductor indium phosphide (InP). Waveguide cantilevers with resonant frequencies as high as 5.78 MHz, a quality factor of 340, and a sensitivity of 4.4x10^16 Hz/g are shown for the first time in this system. The first demonstration of vapor detection using the sensor platform is performed utilizing an organic semiconductor Pentacene absorbing layer. Vapors are measured from mass shifts of 6.56x10^-14 and 7.28x10^-14 g exhibiting a mass detection threshold of 5.09x10^-15 g. The design, fabrication, and testing of an integrated waveguide PIN photodetector with an In0.53Ga0.47As absorbing layer is reported. Dark currents as low as 8.7 nA are measured for these devices. The first demonstration of a resonating cantilever waveguide measurement is also performed using the monolithically integrated waveguide photodiodes with uncertainty of less than ± 35 Hz. Finally, a future outlook is presented for this monolithic InP sensor system.