We present a novel MEMS cantilever waveguide resonator sensing platform utilizing for the first t... more We present a novel MEMS cantilever waveguide resonator sensing platform utilizing for the first time an integrated photodiode readout scheme. This platform uses indium phosphide (InP) to enable the monolithic integration of passive waveguides with active optical components. Cantilever waveguide resonators were successfully fabricated with integrated PIN photodiodes for displacement measurement. On-chip integration of the readout provides a 70% improvement in mass sensitivity compared to off-chip photodetector designs. We have successfully fabricated cantilever waveguides with integrated photodetectors and experimentally characterize these cantilever sensors with monolithically integrated PIN photodiodes.
Abstract-Protein engineering is a rich technology that can be used for chemical vapor detection a... more Abstract-Protein engineering is a rich technology that can be used for chemical vapor detection applications. By utilizing the high specificity and programmability offered by genetic engineering of proteins, a highly selective receptor layer targeting trinitrotoluene (TNT) vapor is developed. This receptor layer consists of a scaffolding made of Tobacco mosaic virus (TMV), whose virus coat protein has been mutated to
Journal of Micromechanics and Microengineering, 2006
Page 1. End-coupled optical waveguide MEMS devices in the indium phosphide material system This a... more Page 1. End-coupled optical waveguide MEMS devices in the indium phosphide material system This article has been downloaded from IOPscience. Please scroll down to see the full text article. 2006 J. Micromech. Microeng. 16 832 ...
ABSTRACT For the first time, a chemical sensor utilizing optical MEMS with a novel adaptive feedb... more ABSTRACT For the first time, a chemical sensor utilizing optical MEMS with a novel adaptive feedback circuit is presented. This circuit implementation of a hill climbing feedback algorithm is capable of autonomously detecting resonant frequency shifts for a range of MEMS resonators. Eight different cantilever-based sensors (width = 0.6-1.4 mum, length = 40-75 mum, and thickness = 1.8 mum), resonating between 200 kHz to 600 kHz, have been measured. Additionally, the circuit has been used to track resonant frequency shifts due to isopropanol (IPA) adsorption on three different chemical sensors. The frequency detection range, measurement resolution, and sensitivity of the system have been evaluated.
Journal of Micromechanics and Microengineering, 2011
The first adaptive feedback circuit capable of detecting resonant frequencies for a wide range of... more The first adaptive feedback circuit capable of detecting resonant frequencies for a wide range of MEMS resonators is presented. The feedback system presented implements a hill-climbing algorithm that sweeps actuation frequencies, locking onto the resonance condition at maximum cantilever amplitude response without limitations on the frequency range. To demonstrate its adaptability, a circuit implementation of this feedback algorithm was used to detect the resonant frequency of eight different cantilever-based sensors (width (W) = 1.4 µm, length (L) = 40-75 µm, and thickness (T) = 1.8 µm), resonating at 201.0 to 592.1 kHz. Additionally, the same circuit was used to track resonant frequency shifts due to isopropanol adsorption on three different chemical sensors with no modifications. The feedback electronics integrated with these resonator sensors provide a mass resolution limit of 123 femptograms. The realization of this system will enable real-time chip-scale sensor systems, providing an alternative to external instrumentation modules that perform sensor control and monitoring.
We present a MEMS cantilever waveguide resonator sensing platform utilizing a novel optical reado... more We present a MEMS cantilever waveguide resonator sensing platform utilizing a novel optical readout scheme and the organic semiconductor pentacene as a surface functionalization layer. Detection of vapor by way of mass induced frequency shift is demonstrated. Frequency shifts due to mass absorption of 509 and 236 Hz were measured to plusmn85 Hz corresponding to a sensitivity of plusmn0.507 pg. The III-V Indium Phosphide (InP) material enables passive waveguides and active optical components to be monolithically integrated, yielding single-chip sensors in the future.
Integrating electronic circuits with micro-electromechanical systems (MEMS) will enable them to b... more Integrating electronic circuits with micro-electromechanical systems (MEMS) will enable them to be smart, versatile, and potentially portable due to the intelligence of electronic circuitry, high sensitivity of MEMS device, and size of electrical components. We present a smart sensor system that utilizes a circuit's compact real-time instrumentation and readout with a MEMS resonator's high sensitivity detection of target analytes. The purpose of the feedback circuit is its integration with a developed in-plane III-V optical resonator system for chemical and biological detection. A resonator sensor utilizes the high sensitivity of cantilever's resonant frequency shift to absorbed mass. Using an integrated system, it will facilitate the testing and data acquisition by replacing multiple macro instrumentation modules. The feedback circuit is based on an optimization algorithm, which is implemented with mixed-signal design using discrete IC components on a circuit board, to track the resonant frequency of a cantilever.
Photolithography is a patterning process that uses light to transfer a pattern from a mask to a p... more Photolithography is a patterning process that uses light to transfer a pattern from a mask to a photosensitive polymer layer. The resulting pattern can either be etched into the underlying surface or used to define the patterning of a layer deposited onto the masked surface. This is essentially a two-dimensional process that can be repeated numerous times to fabricate various structures and devices. A classic use of these techniques is the fabrication of transistors on a silicon substrate as practiced in the semiconductor industry. Development over a number of years has yielded optimization of processing conditions, equipment, and materials to achieve ever smaller sized features and an increased density of integration. In the effort to fabricate even smaller (submicron to nanometer) features, other fabrication methods have also been developed such as electron beam lithography, focused ion beam lithography, and nanoimprint lithography. This chapter presents an introduction and practical approach to lithography and micromachining techniques in the context of MEMS device fabrication. The topics that are discussed here include: UV lithography, grayscale lithography, e-beam lithography, X-ray lithography, direct-write lithographies and imprint lithographies. A detailed description including highlighted examples of each of these lithographic techniques is presented in this chapter. At the end of the chapter a compilation of hands-on case studies is presented to assist readers in implementing these techniques in their own laboratories and developing custom fabrication capabilities that fulfill their own unique requirements.
We present a MEMS cantilever resonator sensing platform in InP utilizing an optical readout schem... more We present a MEMS cantilever resonator sensing platform in InP utilizing an optical readout scheme for applications in biosensing. Devices with resonant frequencies as high as 1 MHz are demonstrated with Q factors of ~160 in air and calculated mass sensitivities as high as Deltam/Deltaf= 4.5 times 10-16g/Hz
Printing methodologies that combine capabilities from both nanoimprint lithography (NIL) and tran... more Printing methodologies that combine capabilities from both nanoimprint lithography (NIL) and transfer printing (TP) have been utilized to fabricate electronic and mechanical device components onto plastic substrates. A wide variety of materials have been utilized in the fabrication of thin-film transistors (TFT) and mechanical resonators.Details of the printing methods and characteristics of the resulting devices will be presented as a function of membrane material, thickness, printing conditions and cavity dimensions.
We present a resonant cantilever sensor for use in chemical and biological sensing applications. ... more We present a resonant cantilever sensor for use in chemical and biological sensing applications. Electrostatically actuated suspended indium phosphide (InP) waveguides are used as the sensing cantilevers. This sensor uses an integrated optical detection scheme which eliminates the need for free space optical components seen in traditional systems. Discussions on device design as well as data collection methods are presented. Mass sensitivity in the range of Deltam = 6.6times10-15 g is reported, comparable to similar cantilever sensor designs. Integration of waveguide cantilever sensors with on chip optical sources and detectors is also discussed
We present a novel MEMS cantilever waveguide resonator sensing platform utilizing for the first t... more We present a novel MEMS cantilever waveguide resonator sensing platform utilizing for the first time an integrated photodiode readout scheme. This platform uses indium phosphide (InP) to enable the monolithic integration of passive waveguides with active optical components. Cantilever waveguide resonators were successfully fabricated with integrated PIN photodiodes for displacement measurement. On-chip integration of the readout provides a 70% improvement in mass sensitivity compared to off-chip photodetector designs. We have successfully fabricated cantilever waveguides with integrated photodetectors and experimentally characterize these cantilever sensors with monolithically integrated PIN photodiodes.
Abstract-Protein engineering is a rich technology that can be used for chemical vapor detection a... more Abstract-Protein engineering is a rich technology that can be used for chemical vapor detection applications. By utilizing the high specificity and programmability offered by genetic engineering of proteins, a highly selective receptor layer targeting trinitrotoluene (TNT) vapor is developed. This receptor layer consists of a scaffolding made of Tobacco mosaic virus (TMV), whose virus coat protein has been mutated to
Journal of Micromechanics and Microengineering, 2006
Page 1. End-coupled optical waveguide MEMS devices in the indium phosphide material system This a... more Page 1. End-coupled optical waveguide MEMS devices in the indium phosphide material system This article has been downloaded from IOPscience. Please scroll down to see the full text article. 2006 J. Micromech. Microeng. 16 832 ...
ABSTRACT For the first time, a chemical sensor utilizing optical MEMS with a novel adaptive feedb... more ABSTRACT For the first time, a chemical sensor utilizing optical MEMS with a novel adaptive feedback circuit is presented. This circuit implementation of a hill climbing feedback algorithm is capable of autonomously detecting resonant frequency shifts for a range of MEMS resonators. Eight different cantilever-based sensors (width = 0.6-1.4 mum, length = 40-75 mum, and thickness = 1.8 mum), resonating between 200 kHz to 600 kHz, have been measured. Additionally, the circuit has been used to track resonant frequency shifts due to isopropanol (IPA) adsorption on three different chemical sensors. The frequency detection range, measurement resolution, and sensitivity of the system have been evaluated.
Journal of Micromechanics and Microengineering, 2011
The first adaptive feedback circuit capable of detecting resonant frequencies for a wide range of... more The first adaptive feedback circuit capable of detecting resonant frequencies for a wide range of MEMS resonators is presented. The feedback system presented implements a hill-climbing algorithm that sweeps actuation frequencies, locking onto the resonance condition at maximum cantilever amplitude response without limitations on the frequency range. To demonstrate its adaptability, a circuit implementation of this feedback algorithm was used to detect the resonant frequency of eight different cantilever-based sensors (width (W) = 1.4 µm, length (L) = 40-75 µm, and thickness (T) = 1.8 µm), resonating at 201.0 to 592.1 kHz. Additionally, the same circuit was used to track resonant frequency shifts due to isopropanol adsorption on three different chemical sensors with no modifications. The feedback electronics integrated with these resonator sensors provide a mass resolution limit of 123 femptograms. The realization of this system will enable real-time chip-scale sensor systems, providing an alternative to external instrumentation modules that perform sensor control and monitoring.
We present a MEMS cantilever waveguide resonator sensing platform utilizing a novel optical reado... more We present a MEMS cantilever waveguide resonator sensing platform utilizing a novel optical readout scheme and the organic semiconductor pentacene as a surface functionalization layer. Detection of vapor by way of mass induced frequency shift is demonstrated. Frequency shifts due to mass absorption of 509 and 236 Hz were measured to plusmn85 Hz corresponding to a sensitivity of plusmn0.507 pg. The III-V Indium Phosphide (InP) material enables passive waveguides and active optical components to be monolithically integrated, yielding single-chip sensors in the future.
Integrating electronic circuits with micro-electromechanical systems (MEMS) will enable them to b... more Integrating electronic circuits with micro-electromechanical systems (MEMS) will enable them to be smart, versatile, and potentially portable due to the intelligence of electronic circuitry, high sensitivity of MEMS device, and size of electrical components. We present a smart sensor system that utilizes a circuit's compact real-time instrumentation and readout with a MEMS resonator's high sensitivity detection of target analytes. The purpose of the feedback circuit is its integration with a developed in-plane III-V optical resonator system for chemical and biological detection. A resonator sensor utilizes the high sensitivity of cantilever's resonant frequency shift to absorbed mass. Using an integrated system, it will facilitate the testing and data acquisition by replacing multiple macro instrumentation modules. The feedback circuit is based on an optimization algorithm, which is implemented with mixed-signal design using discrete IC components on a circuit board, to track the resonant frequency of a cantilever.
Photolithography is a patterning process that uses light to transfer a pattern from a mask to a p... more Photolithography is a patterning process that uses light to transfer a pattern from a mask to a photosensitive polymer layer. The resulting pattern can either be etched into the underlying surface or used to define the patterning of a layer deposited onto the masked surface. This is essentially a two-dimensional process that can be repeated numerous times to fabricate various structures and devices. A classic use of these techniques is the fabrication of transistors on a silicon substrate as practiced in the semiconductor industry. Development over a number of years has yielded optimization of processing conditions, equipment, and materials to achieve ever smaller sized features and an increased density of integration. In the effort to fabricate even smaller (submicron to nanometer) features, other fabrication methods have also been developed such as electron beam lithography, focused ion beam lithography, and nanoimprint lithography. This chapter presents an introduction and practical approach to lithography and micromachining techniques in the context of MEMS device fabrication. The topics that are discussed here include: UV lithography, grayscale lithography, e-beam lithography, X-ray lithography, direct-write lithographies and imprint lithographies. A detailed description including highlighted examples of each of these lithographic techniques is presented in this chapter. At the end of the chapter a compilation of hands-on case studies is presented to assist readers in implementing these techniques in their own laboratories and developing custom fabrication capabilities that fulfill their own unique requirements.
We present a MEMS cantilever resonator sensing platform in InP utilizing an optical readout schem... more We present a MEMS cantilever resonator sensing platform in InP utilizing an optical readout scheme for applications in biosensing. Devices with resonant frequencies as high as 1 MHz are demonstrated with Q factors of ~160 in air and calculated mass sensitivities as high as Deltam/Deltaf= 4.5 times 10-16g/Hz
Printing methodologies that combine capabilities from both nanoimprint lithography (NIL) and tran... more Printing methodologies that combine capabilities from both nanoimprint lithography (NIL) and transfer printing (TP) have been utilized to fabricate electronic and mechanical device components onto plastic substrates. A wide variety of materials have been utilized in the fabrication of thin-film transistors (TFT) and mechanical resonators.Details of the printing methods and characteristics of the resulting devices will be presented as a function of membrane material, thickness, printing conditions and cavity dimensions.
We present a resonant cantilever sensor for use in chemical and biological sensing applications. ... more We present a resonant cantilever sensor for use in chemical and biological sensing applications. Electrostatically actuated suspended indium phosphide (InP) waveguides are used as the sensing cantilevers. This sensor uses an integrated optical detection scheme which eliminates the need for free space optical components seen in traditional systems. Discussions on device design as well as data collection methods are presented. Mass sensitivity in the range of Deltam = 6.6times10-15 g is reported, comparable to similar cantilever sensor designs. Integration of waveguide cantilever sensors with on chip optical sources and detectors is also discussed
Uploads