Andre Bossche
Delft University of Technology, Microelectronics, Faculty Member
Abstract—Nowadays, micro- and nanochips are usually fabricated with Silicon and/or glass. A simple, low-cost and reliable integration packaging method that provides flexibility to the incorporation of electronic and fluidic devices into a... more
Abstract—Nowadays, micro- and nanochips are usually fabricated with Silicon and/or glass. A simple, low-cost and reliable integration packaging method that provides flexibility to the incorporation of electronic and fluidic devices into a system has not been fully developed yet. The use of Printed Circuit Board material as substrate to create dry film resist microfluidic channels is the core technology to provide such an integration method. The feasibility and potential of the proposed packaging method is demonstrated in this work.
Research Interests: Engineering and Printing
Nowadays, the methods used to determine cell concentration either count the cells per volume or measure the cells weight per volume. This paper presents the design, fabrication and measurement of a microfluidic cell trapping device... more
Nowadays, the methods used to determine cell concentration either count the cells per volume or measure the cells weight per volume. This paper presents the design, fabrication and measurement of a microfluidic cell trapping device envisaged for cell concentration measurements. The work presented here focuses mainly in the fabrication of the device. Measurements are made to validate the fabricated device. The device separates different size particles by using dielectrophoresis. Horizontal as well as vertical electric fields can be used to trap the particles by controlling the amplitude and frequency of AC voltage signals. The device presented here is fabricated using low-cost and low-temperature technologies.
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MEMS packaging is an application specific process, there are no extensively applicable standards available. This is one of the reasons why the packaging can take up to 80% of the device fabrication costs. The long-term stability of MEMS... more
MEMS packaging is an application specific process, there are no extensively applicable standards available. This is one of the reasons why the packaging can take up to 80% of the device fabrication costs. The long-term stability of MEMS devices is determined mainly by the package. The goal of this work is to study the reliability and stability issues related to resonant mode micromechanical devices operating in ambient environment. After characterizing the failure mechanisms, we try to determine the minimum requirements for proper packaging to provide stable device operation. Stiffening effect and degrading shock response were found on thin SiN and SiC cantilever beams. The environment has strong influence on these effects; humidity increased, while nitrogen and argon decreased the stiffening effect and the shock response. These results offer cheap atmospheric packaging solution in inert gasses. Electrostatic flycatcher effect was found on crystalline Si resonator beams, which points out the necessity of a dust-free package and/or electric grounding of the resonators
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In this paper, we report the separation of 6 biologically relevant organic acids in a capillary electrophoresis microchip. Electrophoretic separation was done in a fully-glass microchip into which four contactless electrodes were... more
In this paper, we report the separation of 6 biologically relevant organic acids in a capillary electrophoresis microchip. Electrophoretic separation was done in a fully-glass microchip into which four contactless electrodes were integrated for conductivity detection. The microchip design, the electronic interface, and the injection setup are described. Concentrations down to 50 μM (each) of the mixture of organic acids could be detected.
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Ammonium levels in sweat can potentially be used to measure muscle fatigue and to diagnose particular metabolic myopathies. To research the potential use of ammonia in sweat as a biomarker, a new real-time monitoring system is developed.... more
Ammonium levels in sweat can potentially be used to measure muscle fatigue and to diagnose particular metabolic myopathies. To research the potential use of ammonia in sweat as a biomarker, a new real-time monitoring system is developed. This system consists of a capsule that is placed on the skin and ventilated with dry air. A metal-oxide gas sensor in the capsule detects the ammonia that is evaporated from sweat. The sensor system was built, and calibration experiments were performed. The sensors show good sensitivity from 27 mV/ppm to 1.1 mV/ppm in the desired measurement range of 1 to 30 ppm, respectively. A temperature and humidity sensor is integrated to compensate for temperature and humidity effects on the NH3 sensor.
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Capacitors made of interdigitated electrodes (IDEs) as a transducer platform for the sensing of volatile organic compounds (VOCs) have advantages due to their lower power operation and fabrication using standard micro-fabrication... more
Capacitors made of interdigitated electrodes (IDEs) as a transducer platform for the sensing of volatile organic compounds (VOCs) have advantages due to their lower power operation and fabrication using standard micro-fabrication techniques. Integrating a micro-electromechanical system (MEMS), such as a microhotplate with IDE capacitor, further allows study of the temperature- dependent sensing response of VOCs. In this paper, the design, fabrication, and characterization of a low-power MEMS microhotplate with IDE capacitor to study the temperature-dependent sensing response to methanol using Zeolitic imidazolate framework (ZIF-8), a class of metal-organic framework (MOF), is presented. A Titanium nitride (TiN) microhotplate with aluminum IDEs suspended on a silicon nitride membrane is fabricated and characterized. The power consumption of the ZIF-8 MOF-coated device at an operating temperature of 50 ∘ C is 4.5 mW and at 200 ∘ C it is 26 mW. A calibration methodology for the effects...
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The in situ electrochemical growth of Cu benzene-1,3,5-tricarboxylate (CuBTC) metal-organic frameworks, as an affinity layer, directly on custom-fabricated Cu interdigitated electrodes (IDEs) is described, acting as a transducer.... more
The in situ electrochemical growth of Cu benzene-1,3,5-tricarboxylate (CuBTC) metal-organic frameworks, as an affinity layer, directly on custom-fabricated Cu interdigitated electrodes (IDEs) is described, acting as a transducer. Crystalline 5-7 µm thick CuBTC layers are grown on IDEs consisting of 100 electrodes with a width and a gap of both 50 µm and a height of 6-8 µm. These capacitive sensors are exposed to methanol and water vapor at 30 °C. The affinities show to be completely reversible with higher affinity toward water compared to methanol. For exposure to 1000 ppm methanol, a fast response is observed with a capacitance change of 5.57 pF at equilibrium. The capacitance increases in time followed diffusion-controlled kinetics (k = 2.9 mmol s(-0.5) g(-1)CuBTC ). The observed capacitance change with methanol concentration follows a Langmuir adsorption isotherm, with a value for the equilibrium affinity Ke = 174.8 bar(-1) . A volume fraction fMeOH = 0.038 is occupied upon expos...
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ABSTRACT A device for carrying out a reaction, which device comprises a wafer provided with a group of at least two wells. The wells are thermally separate from each other by means of a groove in a layer of the device, while parts... more
ABSTRACT A device for carrying out a reaction, which device comprises a wafer provided with a group of at least two wells. The wells are thermally separate from each other by means of a groove in a layer of the device, while parts separated by the groove are locally connected by bridges. In this way a device is provided combining great mechanical strength with good thermal insulation.
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The present paper introduces a magnetic-field sensor based on a resonating single-crystal silicon structure. The excitation of the resonator is achieved by the Lorentz force generated by a sinusoidal current flowing through a rectangular... more
The present paper introduces a magnetic-field sensor based on a resonating single-crystal silicon structure. The excitation of the resonator is achieved by the Lorentz force generated by a sinusoidal current flowing through a rectangular coil deposited on the surface of the structure. The amplitude of the vibration, which is proportional to the magnetic field, is detected by sensing capacitors. Because
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SUMMARY This paper reports the calculation of the Q-factor of a torsional resonator in the low pressure region if the vibration occurs in free-space or close to another surface. 'The calculation is based on the model used... more
SUMMARY This paper reports the calculation of the Q-factor of a torsional resonator in the low pressure region if the vibration occurs in free-space or close to another surface. 'The calculation is based on the model used by R.G. Christian 111 but a modified Maxwell-Boltzmann distribution, the MaxwellianStream distribution is applied to describe the velocity distribution of the gas particles
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ABSTRACTThe mechanical and resonant properties of thin film resonators are influenced by the surrounding environment. Adsorption- and surface oxidation-induced stiffening effect was observed on silicon nitride and silicon carbide... more
ABSTRACTThe mechanical and resonant properties of thin film resonators are influenced by the surrounding environment. Adsorption- and surface oxidation-induced stiffening effect was observed on silicon nitride and silicon carbide cantilever beams. The resonance frequency increased logarithmically in time upon exposure to ambient air. The variations of surface stress and spring constant of the SiNx cantilever beam were calculated. Further oxynitride formation on the surface increased the stability of the resonators. The shock response of the structures was studied in various environments. The resonance frequency abruptly dropped due to cracking of the absorbed surface layer, than recovered logarithmically. The initial drop and the recovery rate is environment dependant. Humidity increased, while argon and nitrogen rich environments mitigated the degrading effects. The SiCx is more inert to the environmental effects and proved to be a promising candidate as structural material in reso...
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is 5 m with a microscope-based system and 100 m for an embedded photodiode system. The photodiode system also provides a detection limit of 2.4 m for ATP/luciferase bioluminescence. Introduction The past decade has seen a rapid growth in... more
is 5 m with a microscope-based system and 100 m for an embedded photodiode system. The photodiode system also provides a detection limit of 2.4 m for ATP/luciferase bioluminescence. Introduction The past decade has seen a rapid growth in the use of microtechnology to produce ever-smaller instrumentation systems for use in medical diagnostics, studies in cell biology, biochemical process control, and the detection of contaminants and pathogens in the environment. The general goal of these systems is to provide high-speed, low-cost, reliable measurements of various biochemical molecules that occur either naturally or as markers. The objective of our research over the past few years has been to design and build an intelligent analytical system that measures different molecular analytes simultaneously using specific molecular interactions in wells on specially constructed chips. The technology we propose is generic and could be useful in a variety of applications, such as quality manag
When light passes through a hole smaller than the wavelength of the light, the transmission is very low and the light is diffracted. This however changes if holes are arranged in a periodic array on metal. In that case the light couples... more
When light passes through a hole smaller than the wavelength of the light, the transmission is very low and the light is diffracted. This however changes if holes are arranged in a periodic array on metal. In that case the light couples to surface plasmons; this results in enhanced transmission, spectral selection and a small angular diffraction. We develop a novel microscopic method based on a periodic hole-array, which will be used as a multiple-apertures near-field source for illuminating a biological sample while the light is collected in far-field. The measurement speed is high, due to the use of an array instead of a single source. The main advantage of this microscope originates from the low diffraction of light through a relatively thick sample with enhanced transmission. It results in the ability to measure the samples interior and 3D reconstruction can be made by semi-confocal techniques. This overcomes the major limitation of near-field methods for which only a shallow la...
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Liquid conductivity detection for application in chip-based capillary electrophoresis (CE) has received attention because the sensor electrodes can be integrated in the chip and there is no loss of sensitivity when downscaling the... more
Liquid conductivity detection for application in chip-based capillary electrophoresis (CE) has received attention because the sensor electrodes can be integrated in the chip and there is no loss of sensitivity when downscaling the detector. A well known disadvantage of conductivity detection is the high level of the baseline (due to the conductivity of the carrier electrolyte) that has a high influence on the measured values and deteriorates the detection limit. By using a lockin amplifier, making use of its two differential inputs and of its phase-locked sinewave output, we can generate a signal of controlled amplitude and phase, related to the level and phase of the baseline signal. By subtracting this signal from the AC output signal of the detector the baseline is significantly suppressed. Ideally, only the changes of the background signal are then measured. When applying the baseline-suppression method to real measurements, the level of the background signal was decreased 50 times. The detection limit (which is related to the signal-to-noise ratio) was found to be 10 times lower. Reproducible separations with concentrations from 1 mM down to 10 μM of potassium, sodium, and lithium ions were obtained. For our separation and detection system, the concentration of 10 μM could not be detected without the baseline-suppression technique described here.
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An ultrasound wireless positioning system is developed to localize the laparoscopic instruments inside the patient's body. The cross correlation method applied for measuring time of flight of ultrasound bursts yields 1 mm resolution... more
An ultrasound wireless positioning system is developed to localize the laparoscopic instruments inside the patient's body. The cross correlation method applied for measuring time of flight of ultrasound bursts yields 1 mm resolution in determining the instrument position. The 90° or respectively 180° phase-shift is introduced after the first half of the ultrasound burst.
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... of bacterial based on the thermomechanical noise of a nanomechanical resonator: origin of the response and detection limits", Nanotechnology, vol. 19, 2008. [16] H. Sadeghian, CK Yang, KB Gavan, JFL Goosen, EWJM... more
... of bacterial based on the thermomechanical noise of a nanomechanical resonator: origin of the response and detection limits", Nanotechnology, vol. 19, 2008. [16] H. Sadeghian, CK Yang, KB Gavan, JFL Goosen, EWJM van der Drift, HSJ van der Zant, PJ French, A. Bossche. ...
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... 299303 ACT ORS A PHYSICAL Quality factor of torsional resonators in the lowpressure region Zsolt Kfidr *, Wilko Kindt, Andre Bossche, Jeff Mollinger Delft ... MS) distribution [5]. 4. The modified velocity distribution The group of... more
... 299303 ACT ORS A PHYSICAL Quality factor of torsional resonators in the lowpressure region Zsolt Kfidr *, Wilko Kindt, Andre Bossche, Jeff Mollinger Delft ... MS) distribution [5]. 4. The modified velocity distribution The group of particles of an equilibrium gas that strike a wall of a ...
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This paper introduces a computer aided reliability system, which allows the modelling of production systems and which is able to generate causal trees, fault trees and cause consequence diagrams automatically, using the predefined... more
This paper introduces a computer aided reliability system, which allows the modelling of production systems and which is able to generate causal trees, fault trees and cause consequence diagrams automatically, using the predefined component and system models