Enhancement of an indium phosphide resonator sensor microsystem through the development of an adaptive feedback circuit and electrospray deposition

by Xiao Zhu Fan

Institution: University of Maryland
Department: Electrical Engineering
Year: 2009
Record ID: 1851542
Full text PDF: http://hdl.handle.net/1903/9679


Cantilever resonator sensor enhancement through the development of an adaptive feedback circuit and the use of electrospray deposition is presented. The feedback system adapts to a wide range of resonators by implementing a hill climbing algorithm, locking onto the cantilever's resonance condition. Eight different cantilever-based sensors (Length=40-75μm), resonating at 201.0kHz to 592.1kHz, with a minimum standard deviation of 11.8Hz, corresponding to a mass resolution limit of 123fg for the device, have been dynamically detected using a single circuit. Electrospray deposition of thin-films on multiple substrate materials and released microstructures has been performed. An average deposition rate of 9.5±5nm/min was achieved with an average surface roughness of 4.5nm on a 197nm thick film. This technology will enable a post-processing method for depositing absorbing layers for sensing applications. With the development of these two technologies, the practical functionality of a chip-scale sensor microsystem will be more readily realized.