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Wolffenbuttel, R.F. (author), Ghaderi, M. Amir (author)Metasurface coatings on a free-standing SiN thin film membrane are fabricated on a Si substrate using masked lithography and CMOS-compatible surface micromachining. The result is a band-limited absorber for the mid-IR, which is part of a microstructure that is attached to the substrate by long and slender suspension beams to provide thermal...journal article 2023
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Wolffenbuttel, R.F. (author), Ghaderi, M. (author)The use of masked UV (i-line) lithography in a MEMS foundry for CMOS-compatible fabrication of large-area metasurface-based absorbers for the mid-infrared is demonstrated. The challenges are in: (a) the limited number of acceptable metals, (b) the thickness tolerance of the layers used in the CMOS process, and (c) the imaging capabilities of...journal article 2022
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Mirza Gheytaghi, Amir (author), Ghaderi, M. (author), Vollebregt, S. (author), Ahmadi, M. (author), Wolffenbuttel, R.F. (author), Zhang, Kouchi (author)In this paper, the growth of optimized vertically aligned multi-walled carbon nanotube (VA-MWCNT) forests by LPCVD method for use in a large-area absorber in infrared detectors is presented. The effect of synthesis temperature (500−700 °C) and time (1−10 min) on the optical absorption coefficient in the infrared (2−20 μm) is investigated by...journal article 2020
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Middelburg, L.M. (author), Ghaderi, M. (author), Visser, J.H. (author), Wolffenbuttel, R.F. (author)The resistive particulate matter sensor is a simple device that transduces the presence of soot through impedance change across inter-digital electrodes (IDEs). We investigate the information provided by impedance spectroscopy over the frequency range from 100 Hz to 10 kHz for two purposes. The first is to investigate the opportunities for an...journal article 2020
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Middelburg, L.M. (author), Ghaderi, Mohammadamir (author), Bilby, David (author), Visser, J.H. (author), Zhang, Kouchi (author), Wolffenbuttel, R.F. (author)Impedance spectroscopy in the frequency range 100 Hz to 10 kHz has been applied to the Inter-Digitated Electrode (IDE) structure that is conventionally operated as a resistive sensor for the measurement of Particulate Matter (PM). The measurement of both the in-phase (resistive) and out-of-phase (capacitive) components of the impedance over this...conference paper 2020
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Middelburg, L.M. (author), Ghaderi, Mohammadamir (author), Bilby, David (author), Visser, Jaco H. (author), Zhang, Kouchi (author), Lundgren, Per (author), Enoksson, Peter (author), Wolffenbuttel, R.F. (author)Ensuring optical transparency over a wide spectral range of a window with a view into the tailpipe of the combustion engine, while it is exposed to the harsh environment of sootcontaining exhaust gas, is an essential pre-requisite for introducing optical techniques for long-term monitoring of automotive emissions. Therefore, a regenerable...journal article 2020
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Ghaderi, M. (author), Karimi Shahmarvandi, Ehsan (author), Wolffenbuttel, R.F. (author)The design and fabrication of wideband mid-infrared metamaterial absorbers are presented. The emphasis is put on the shape-tolerant design for using masked UV (i-line) lithography and CMOS-compatible fabrication to enable on-chip co-integration with detector and readout circuits in a MEMS foundry while maintaining wafer throughput. The...journal article 2018
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Ghaderi, M. (author), Karimi Shahmarvandi, Ehsan (author), Ayerden, N.P. (author), Wolffenbuttel, R.F. (author)Metamaterial absorbers are photonic structures composed of an array of sub-wavelength metallic patterns. Results in literature are usually based on structures of nominal dimensions, despite the significant effect of fabrication tolerances on performance. This research aims to identify the main sources of uncertainty and to investigate their...conference paper 2017
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Jiang, Bo (author), Ghaderi, M. (author), Bossche, A. (author), Visser, Jaco H. (author), Wolffenbuttel, R.F. (author)Thermal impedance spectroscopy has been investigated as a non-destructive technique to determine the composition of ternary mixtures of biofuels. The principle of the thermal conductivity detector has been extended for measuring both the thermal conductivity and the thermal capacity of biofuel in the range between 1 to 100 Hz, using an AC...conference paper 2017
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Middelburg, L.M. (author), Ghaderi, M. (author), Bossche, A. (author), Bastemeijer, J. (author), de Graaf, G. (author), Wolffenbuttel, R.F. (author), Soltis, Rick (author), Visser, Jaco (author)A capacitive probe is generally used in a flex-fuel engine for measuring the ethanol content in biofuel. However, the water content in biofuel of high ethanol content cannot be disregarded or considered constant and the full composition measurement of ethanol, gasoline and water in biofuel is required. Electrical impedance spectroscopy with a...conference paper 2017
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Middelburg, L.M. (author), de Graaf, G. (author), Bossche, A. (author), Bastemeijer, J. (author), Ghaderi, M. (author), Wolffenbuttel, F.S. (author), Visser, J. (author), Soltis, R. (author), Wolffenbuttel, R.F. (author)Measuring the ethanol/water ratio in biofuel of high ethanol content, such as E85, is important when used in a flex-fuel engine. A capacitive probe is generally used for measuring the ethanol/gasoline ratio. However, the water content in E85 biofuel cannot be disregarded or considered constant and full composition measurement of biofuel is...journal article 2017
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- Ghaderi, M. (author) doctoral thesis 2016
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Middelburg, L.M. (author), de Graaf, G. (author), Ghaderi, M. (author), Bossche, A. (author), Bastemeijer, J. (author), Visser, J.H. (author), Soltis, R.E. (author), Wolffenbuttel, R.F. (author)The optical absorption of water-containing bio-fuel is investigated as a parameter to determine the gasoline content of this fuel. Optical measurements reveal that gasoline shows an interesting and useful spectrum with typical absorption behavior in the UV range between 230 and 300 nm. This result indicates that significant information can be...journal article 2016
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Ayerden, N.P. (author), Ghaderi, M. (author), Wolffenbuttel, R.F. (author)The increasing demand for small, robust and low-cost gas sensors triggers the batch fabrication of highly selective and sensitive miniaturized devices. A linear variable optical filter (LVOF) based microspectrometer enables selectivity in a wide wavelength range, while maintaining the robustness and low cost. To achieve sensitivity in an LVOF...journal article 2016
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Karimi Shahmarvandi, Ehsan (author), Ghaderi, M. (author), Wolffenbuttel, R.F. (author)A CMOS-compatible approach is presented for the fabrication of a wideband mid-IR metamaterial-based absorber on top of a Si3N4 membrane, which contains poly-Si thermopiles. The application is in IR microspectrometers that are intended for implementation in portable microsystem for use in absorption spectroscopy. Although Au is the conventional...journal article 2016
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Karimi Shahmarvandi, Ehsan (author), Ghaderi, M. (author), Ayerden, N.P. (author), de Graaf, G. (author), Wolffenbuttel, R.F. (author)The design of a metamaterial-based absorber for use in a mid-IR microspectrometer-based gas sensor is reported.The microspectrometer consists of a linear variable optical filter (LVOF) that is aligned with an array of thermopiledetectors, which is fabricated on a SiN membrane and covered with the absorber. Special emphasis was put on theCMOS...journal article 2016
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Ayerden, N.P. (author), Ghaderi, M. (author), De Graaf, G. (author), Wolffenbuttel, R.F. (author)The design, fabrication and characterization of a highly integrated optical gas sensor is presented. The gas cell takes up most of the space in a microspectrometer and is the only component that has so far not been miniaturized. Using the tapered resonator cavity of a linear variable optical filter as a gas cell enables ultimate miniaturization,...conference paper 2015
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Ghaderi, M. (author), Ayerden, N.P. (author), De Graaf, G. (author), Wolffenbuttel, R.F. (author)The design and CMOS-compatible fabrication of airgap-based optical filters in a surface micromachining process with sacrificial release using thevapour phase is presented. An airgap-dielectric layer combination offers a higher refractive index contrast, as compared to the conventional all-dielectriclayer based filters, which results in a higher...conference paper 2015
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Ghaderi, M. (author), Ayerden, N.P. (author), De Graaf, G. (author), Wolffenbuttel, R.F. (author)In CMOS-compatible optical filter designs, SiO2 is often used as the low-index material, limiting the optical contrast (nHi/nLo) to about 2. Using the air as low-index material improves the optical contrast by about 50%, thus increasing the reflectivity and bandwidth at a given design complexity. The design and fabrication of a 4-layered air...journal article 2014
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Silva, M.F. (author), Rodrigues, J.A. (author), Oliveira, M.J. (author), Fernandes, A.R. (author), Pereira, S. (author), Costa, C.G. (author), Ghaderi, M. (author), Ayerden, P. (author), Goncalves, L.M. (author), De Graaf, G. (author), Wolffenbuttel, R.F. (author), Correia, J.H. (author)This paper presents the design, fabrication and characterization of two Fabry Perot type optical filters (415 nm and 540 nm) for enabling Narrow Band Imaging (NBI) in medical devices (MD). The two-colour illumination should satisfy a highly specific optical design, which is composed of a thin-film optical filter stack of titanium dioxide (TiO2)...journal article 2014
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