@misc{LeeParkKupniketal., author = {Lee, Hyunjoo J. and Park, Kwan Kyu and Kupnik, Mario and Oralkan, {\"O}mer and Khuri-Yakub, Butrus T.}, title = {Chemical vapor detection using a capacitive micromachined ultrasonic transducer}, series = {Analytical chemistry}, volume = {83}, journal = {Analytical chemistry}, number = {24}, issn = {1520-6882}, doi = {10.1021/ac201626b}, pages = {9314 -- 9320}, language = {en} } @misc{SariogluKupnikVaithilingametal., author = {Sarioglu, Ali Fatih and Kupnik, Mario and Vaithilingam, Srikant and Khuri-Yakub, Butrus T.}, title = {Nanoscale topography of thermally-grown oxide films at right-angled convex corners of silicon}, series = {Journal of The Electrochemical Society}, volume = {159}, journal = {Journal of The Electrochemical Society}, number = {2}, issn = {0013-4651}, doi = {10.1149/2.005202jes}, pages = {79 -- 84}, language = {en} } @misc{ParkLeeKupniketal., author = {Park, Kwan Kyu and Lee, Hyunjoo J. and Kupnik, Mario and Oralkan, {\"O}mer and Ramseyer, Jean-Pierre and Lang, Hans Peter and Hegner, Martin and Gerber, Christoph and Khuri-Yakub, Butrus T.}, title = {Capacitive micromachined ultrasonic transducer (CMUT) as a chemical sensor for DMMP detection}, series = {Sensors and Actuators B: Chemical}, volume = {160}, journal = {Sensors and Actuators B: Chemical}, number = {1}, issn = {0925-4005}, doi = {10.1016/j.snb.2011.09.036}, pages = {1120 -- 1127}, language = {en} } @misc{ParkLeeKupniketal., author = {Park, Kwan Kyu and Lee, Hyunjoo J. and Kupnik, Mario and Khuri-Yakub, Butrus T.}, title = {Fabrication of capacitive micromachined ultrasonic transducers via local oxidation and direct wafer bonding}, series = {Journal of Microelectromechanical Systems}, volume = {20}, journal = {Journal of Microelectromechanical Systems}, number = {1}, issn = {1941-0158}, doi = {10.1109/JMEMS.2010.2093567}, pages = {95 -- 103}, language = {en} } @misc{LinZhuangWongetal., author = {Lin, Der-Song and Zhuang, Xuefeng and Wong, Serena H. and Kupnik, Mario and Khuri-Yakub, Butrus T.}, title = {Encapsulation of Capacitive Micromachined Ultrasonic Transducers Using Viscoelastic Polymer}, series = {Journal of Microelectromechanical Systems}, volume = {19}, journal = {Journal of Microelectromechanical Systems}, number = {6}, issn = {1941-0158}, doi = {10.1109/JMEMS.2010.2076786}, pages = {1341 -- 1351}, language = {en} } @misc{WongKupnikWatkinsetal., author = {Wong, Serena H. and Kupnik, Mario and Watkins, Ronald D. and Butts-Pauly, Kim and Khuri-Yakub, Butrus T.}, title = {Capacitive micromachined ultrasonic transducers for therapeutic ultrasound applications}, series = {IEEE transactions on bio-medical electronics}, volume = {57}, journal = {IEEE transactions on bio-medical electronics}, number = {1}, issn = {0018-9294}, pages = {114 -- 123}, language = {en} } @misc{LeeParkKupniketal., author = {Lee, Hyunjoo J. and Park, Kwan Kyu and Kupnik, Mario and Melosh, Nicholas A. and Khuri-Yakub, Butrus T.}, title = {Mesoporous thin-film on highly sensitive resonant chemical sensors for relative humidity and CO2 detection}, series = {Analytical Chemistry}, volume = {84}, journal = {Analytical Chemistry}, number = {7}, issn = {1520-6882}, doi = {10.1021/ac300225c}, pages = {3063 -- 3066}, abstract = {Distributed sensing of gas-phase chemicals is a promising application for mesoporous materials when combined with highly sensitive miniaturized gas sensors. We present a direct application of a mesoporous silica thin film on a highly sensitive miniaturized resonant chemical sensor with a mass sensitivity at the zeptogram scale for relative humidity and CO2 detection. Using mesoporous silica thin-film, we report one of the lowest volume resolutions and a sensitive detection of 5.1 × 10-4\% RH/Hz to water vapor in N2, which is 70 times higher than a device with a nontemplated silica layer. In addition, a mesoporous thin-film that is functionalized with an amino-group is directly applied on the resonant sensor, which exhibits a volume sensitivity of 1.6 × 10-4\%/Hz and a volume resolution of 1.82 × 10-4\% to CO2 in N2.}, language = {en} } @misc{LeeParkKupniketal., author = {Lee, Hyunjoo J. and Park, Kwan Kyu and Kupnik, Mario and Khuri-Yakub, Butrus T.}, title = {Functionalization layers for CO2 sensing using capacitive micromachined ultrasonic transducers}, series = {Sensors and Actuators B: Chemical}, journal = {Sensors and Actuators B: Chemical}, number = {174}, issn = {0925-4005}, pages = {87 -- 93}, abstract = {Sensing of carbon dioxide(CO2)using inexpensive, miniaturized,and highly sensitive sensors is of great interest for environmental and consumer applications. In this paper, we present four functionalization layers that are suitable for resonant sensors based on mass-loading for CO2 detection. We compare the volume sensitivities of these layers to CO2 and relative humidity (RH) by using a highly sensitive 50-MHz capacitive micromachined ultrasonic transducer (CMUT) as a resonant sensor. Among the four function-alization layers, the layer based on a guanidine polymer exhibits the highest volume sensitivity to CO2 of 1.0 ppm/Hz in N2 and 3.8 ppm/Hz in air (∼45\%RH). Furthermore, we report on other important characteristics of the guanidine polymer for sensing applications, including polymer saturation, regeneration, and repeatability.}, language = {en} }