Csaba Dücső - Academia.edu (original) (raw)

Papers by Csaba Dücső

HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific re... more HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

Microsystem Technologies-micro-and Nanosystems-information Storage and Processing Systems, Oct 3, 2022

Due to their complex electro-thermal characteristics microhotplates used in environmental gas sen... more Due to their complex electro-thermal characteristics microhotplates used in environmental gas sensors require careful design to exhibit uniform temperature and low power dissipation during the expected long time operation. The layout design becomes more complex if the multiple operational parameters required by the battery operation and the driver and readout logic are considered. In this paper, we describe a simple analytical filament design procedure to determine the dimensions of the annular metal filament exhibiting uniform surface temperature without additional heat distribution layer. The presented method operates with the cumulative thermal losses towards the ambient and heat conduction via the membrane. Moreover, it handles the operation requirements like the targeted temperature in the atmospheric environment, supply voltage range, current density, filament layer thickness and its coverage ratio. The efficacy of the method is demonstrated by electrical and thermal characterisation of the manufactured devices having 150 lm diameter active area. The microheater achieves the targeted 500°C operation temperature with 1.4-1.55 V supply. The temperature nonuniformity along the filament was measured by Spectral pyrometry and was found to decrease from ± 3.5% to ± 1% when the temperature was raised from 530 to 830°C.

Chemosensors

A reduced size thermocatalytic gas sensor was developed for the detection of methane over the 20%... more A reduced size thermocatalytic gas sensor was developed for the detection of methane over the 20% of the explosive concentration. The sensor chip is formed from two membranes with a 150 µm diameter heated area in their centers and covered with highly dispersed nano-sized catalyst and inert reference, respectively. The power dissipation of the chip is well below 70 mW at the 530 °C maximum operation temperature. The chip is mounted in a novel surface mounted metal-ceramic sensor package in the form-factor of SOT-89. The sensitivity of the device is 10 mV/v%, whereas the response and recovery times without the additional carbon filter over the chip are <500 ms and <2 s, respectively. The tests have shown the reliability of the new design concerning the hotplate stability and massive encapsulation, but the high degradation rate of the catalyst coupled with its modest chemical power limits the use of the sensor only in pulsed mode of operation. The optimized pulsed mode reduces th...

Microsystem Technologies

Due to their complex electro-thermal characteristics microhotplates used in environmental gas sen... more Due to their complex electro-thermal characteristics microhotplates used in environmental gas sensors require careful design to exhibit uniform temperature and low power dissipation during the expected long time operation. The layout design becomes more complex if the multiple operational parameters required by the battery operation and the driver and readout logic are considered. In this paper, we describe a simple analytical filament design procedure to determine the dimensions of the annular metal filament exhibiting uniform surface temperature without additional heat distribution layer. The presented method operates with the cumulative thermal losses towards the ambient and heat conduction via the membrane. Moreover, it handles the operation requirements like the targeted temperature in the atmospheric environment, supply voltage range, current density, filament layer thickness and its coverage ratio. The efficacy of the method is demonstrated by electrical and thermal character...

Przedmiotem niniejszej pracy jest badanie systemów sterowania robota Robin Heart PVA (ang. Port V... more Przedmiotem niniejszej pracy jest badanie systemów sterowania robota Robin Heart PVA (ang. Port Vision Able) z zastosowaniem specjalnych mikroczujników siły 3D MEMS. Postawiono trzy różne sposoby wykorzystania opracowywanych czujników: (1) jako czujnik siły wykorzystany jako mikrodżojstik zintegrowany w rękojeścią narzędzia endoskopowego, aby łatwo kontrolować ruch robota wizyjnego podczas pracy chirurga; (2) jako czujnik siły wewnątrz szczęki narzędzia endoskopowego dla dostarczenia informacji zwrotnej do operatora-chirurga, mierząc siłę chwytu; (3) jako czujnik wielowymiarowy dotyku na końcu narzędzia chirurgicznego, co ułatwia badanie palpacyjne do diagnostyki tkanek podczas pracy. Artykuł ten jest studium wykonalności w zakresie proponowanych zastosowań. Model sterowania robota przy użyciu prototypowego czujnika siły 3D został pomyślnie przetestowany w badaniach funkcjonalnych robota. Wstępne badania sensorów wykazały ich przydatność dla sterowania robotem ze sprzężeniem siłowym, aby ocenić stan tkanek oraz do oceny siły docisku chirurgicznego chwytaka.

The subject aim of the this work is the inves ga on studying of applicability of 3D MEMS based fo... more The subject aim of the this work is the inves ga on studying of applicability of 3D MEMS based force micro-sensors made by 3D MEMSmicromachining technology and use it as micro-joys ck to control the posi on of robot Robin Heart PVA. Since the robot moves with 5 degrees of freedom to run u lise all the possibili es of movement is done available by the use of the switching clutch control object. By pressing the in appropriate mode (way) the sensor provides the ability to control the func ons of the spherical robot (at diff erent speeds): to lean forward or sideways or alterna vely to penetrate or withdrow withdraw and to rotate of the tool axis is possible. The sensor was fastened in its special of the surgical tool. AnApplicability of appropriate control system equipped with a newthis novel sensor was inves gated in and a comparison with to the control using the classic remote control methodswas invesgated. Preliminary tests of laparoscope integrated force sensors were also inves gat...

Proceedings, 2018

Smart laparoscope device was developed and integrated into the ROBIN HEART surgery robot system. ... more Smart laparoscope device was developed and integrated into the ROBIN HEART surgery robot system. Miniaturised silicon based force sensors were developed and integrated into laparoscope tweezers for the special applications. Different sensors were applied to detect tactile information at the tip of the laparoscope and to measure the clamping force between the tweezers. Preliminary tests were accomplished to evaluate the force and tactile signals of the integrated sensors during interventions. Tactile measurements were implemented on artificial and real animal tissues to prove the applicability of the device for biomechanical screening during Minimal Invasive Surgery.

Microelectronics Reliability, 2017

This work established the correlation between the location of temperature gradients and the posit... more This work established the correlation between the location of temperature gradients and the positions where breakdown is observed on different Pt filament layouts in cantilever and full membrane type micro-hotplates. Focusing on practical aspects like in real operation, self-heating was applied to investigate the limitations of high temperature application and to reveal the fatal failure mechanisms. Besides electromigration, another phenomenon playing dominant role in the breakdown of the filaments, the temperature gradient driven thermomigration of Pt was identified. This limits the local allowable temperature gradient to b0.4°C/μm for operation temperature above 700°C.

Journal of Crystal Growth, 2017

Broad spectrum InGaAsP/InP light emitting heterostructures were grown by low temperature liquid p... more Broad spectrum InGaAsP/InP light emitting heterostructures were grown by low temperature liquid phase epitaxy (LPE). The structure of the LED wafers was investigated by optical transmission measurements, and the layer thicknesses were also measured by electron microscopy. Two quaternary light emitting layers of different composition were built in one device structure in order to broaden the usable wavelength range of the emission spectrum. One of the layers is electrically, whereas the other is optically excited as a result of internal absorption and re-emission of the LED light. As a result of this absorption and re-emission process the modified LED chips have substantially broader emission spectra and higher radiance than the conventional surface emitting multi-wavelength NIR LED structures. The two emission peaks of the spectrum were designed for matching the first and second harmonic wavelength of the fundamental absorption band of C-H bonds. The internal quantum efficiency of the wavelength conversion in this type of LEDs is nearly 100%. Keywords  A1. Optical characterization;  A3. Liquid phase epitaxy;  B1. GaInAsP  B2. Semiconducting III-V materials;  B3. Infrared devices Highlights • New broad spectrum single chip GaInAsP/InP LEDs are prepared. • The broad spectrum LEDs have at least two GaInAs(P) infrared light emitting layers. • Low temperature LPE growth is used for production of the device structures. • Devices are optimized for application in near infrared spectroscopy.

Procedia Engineering, 2016

Various deposition techniques were tested to form Pt catalyst on nano-structured materials charac... more Various deposition techniques were tested to form Pt catalyst on nano-structured materials characterized by 50-200 nm dimensions. Different layer structures applied in gas sensing were sensitized by Pt sputtering and droplet deposition of Pt nanoparticles formed from H2[PtCl6] solutions. Besides, atomic layer deposition (ALD) of Pt was also investigated. The layers to be coated were disordered piles of WO3 nano-rods and sol-gel deposited WO3 nano-crystals as well as electrochemically formed alumina with high aspect ratio perpendicular pores. Distribution of Pt particles inside these layers was analyzed by scanning (SEM) and transmission electron microscopy (TEM). Demonstration of functionality is also provided.

Procedia Engineering, 2016

3D contact force sensors were developed and integrated in a demonstration system for testing the ... more 3D contact force sensors were developed and integrated in a demonstration system for testing the feasibility of their application in minimal invasive surgery (MIS). Piezoresistive MEMS based vectorial force sensors were designed and fabricated by 3D silicon micromachining technology and packaged according to their proposed transducer and sensor applications. In this work we demonstrated the integrability and functional applicability of the 3D force sensors in MIS robotic systems to improve their flexibility and reliability by providing real-time force and tactile information during the operation. The final goal is to integrate the new subsystems in the Robin Heart surgery robot of FRK. [1] Three different functions are targeted: 1. Micro-joystick actuator to be integrated in the hilt of the laparoscope to easily control robotic movement during operation. 2. Force sensor inside the laparoscopic jaw to provide feedback to the surgeon by measuring the grasping strength and 3. 3D force/tactile sensor which facilitates palpation for tissue diagnostics during operation. In this paper we demonstrate a feasibility study regarding these proposed applications.

2016 Symposium on Design, Test, Integration and Packaging of MEMS/MOEMS (DTIP), 2016

1997 International Semiconductor Conference 20th Edition. CAS '97 Proceedings

The application of commercial 3-D software "COSMOS" for the design and thermal analysis of the lo... more The application of commercial 3-D software "COSMOS" for the design and thermal analysis of the low power consumption test structures with dielectric membrane for gas microsensors is presented. Within this work, the simulation provides the estimation of the temperature profile on the active area and thg whole membrane including the four bridges and the heating efficianty in the temperature range 20-5OO0C. Unravelling of the heat loss mechanisms in terms of radiation, convection, conduction by air and solid materials during heat transfer on the dielectric membrane is reported for the first time as a mean to evaluate by 3-D simulation the contribution of technological processes and layout design to the total heat losses.

Nanopages, 2006

The deposition of nanowires for interconnects in nanoelectronic devices were studied morphologica... more The deposition of nanowires for interconnects in nanoelectronic devices were studied morphologically by scanning electron microscopy (SEM), atomic force microscopy (AFM) and by in-situ resistance measurements. The deposition and basic characterization of nanometer size tungsten wires by gas injection (GIS) and focused ion beams (FIB) was carried out in-situ in a LEO 1540 XB workstation. The I(V) measurement showed that the deposited W wires have ohmic characteristic. The variation of the resistance during an ex-situ heating was linear with a low thermal coefficient (4% of the pure metallic W).

Procedia Engineering, 2014

Micro-pellistors capable to detect hydrocarbons below 50 mW power consumption at 550 o C operatio... more Micro-pellistors capable to detect hydrocarbons below 50 mW power consumption at 550 o C operation temperature were developed by a novel processing technique. On the top of the full membrane type micro-heaters 1.4 μm thick porous alumina was formed by laterally selective electrochemical etching of the deposited aluminum layer. The porous alumina of the active element is selectively covered by finely dispersed Pt catalyst using alternative methods; such as dropping of H 2 [PtCl 6 ] and sputtering technique, all aiming at deposition of controlled volume and structure of the catalyst. Constant current method in a Wheatstone-bridge configuration was applied in functional tests.

Sensors and Actuators B: Chemical, 2015

The effect of WO 3 nano-crystal characteristic size and layer morphology on gas sensitive propert... more The effect of WO 3 nano-crystal characteristic size and layer morphology on gas sensitive properties was investigated in order to define the optimum preparation process. WO 3 layers were synthesized by hydrothermal acidic precipitation method using different chemicals and reactive sputtering as reference. Micro-hotplate based conductivity type devices were fabricated and the sensitivity on NH 3 up to 100 ppm was measured in the temperature range of 140-240 • C. The measurements revealed that the characteristic size of the WO 3 nano-crystal plays primary role, but layer morphology opens the way towards extended measuring range. The nano-rod structures operated at 220 • C exhibit the best sensing characteristics in terms of sensitivity and stability over wide range of relative humidity.

Procedia Engineering, 2014

In the past half century the IC technology could produce an unprecedented growth and penetration ... more In the past half century the IC technology could produce an unprecedented growth and penetration into all segments of our daily life due to the achieved extreme productivity and reliability by using well established and continuously refined processing platforms. This uninterrupted trend continued also with the advent of the More than Moore-type MEMS technology allowing the combination of the signal processing capability of the mature IC technology with the exploitation of mechanical, thermal, optical properties of the materials used in IC technology in different sensing and actuation purposes. Mass producibility by monolithic integration required here also the development of appropriate unified set of techniques for the various applications, i.e. sort of standardised platforms to explore. In this paper we focus on the development of bulk micromachined membrane platforms, being exploited in such applications. At the same time this summary also offers a "case study", a retrospective review of the development of

of the main scientific results obtained in the project Background As reported earlier, our indust... more of the main scientific results obtained in the project Background As reported earlier, our industrial partner, who played a fundamental role in the design, construction and servicing of the Solar Cell Technology Innovation Centre installed at MFA was BudaSolar Ltd.. Unfortunately, in 2011 the company went bankrupt. Thereby we lost our technical backup, in the existing apparatus the original co-evaporation concept for all four constituents became in this way obsolete. During the one year suspension of the project permitted by the OTKA Collegium we made efforts to find alternative solutions for the hardware deficiency-related issues.

The structure and composition of multilayered SiN x structures prepared by low pressure chemical ... more The structure and composition of multilayered SiN x structures prepared by low pressure chemical vapour deposition were studied by cross-sectional transmission electron microscopy and spectroscopic ellipsometry. Using appropriate deposition parameters and post deposition annealing, well separated Si nanocrystals were obtained with avarage grain size of 8-10 nm.

Procedia Engineering, 2014

Tungsten oxide nano-powders were prepared by acidic precipitation from sodium tungstate solution.... more Tungsten oxide nano-powders were prepared by acidic precipitation from sodium tungstate solution. The alternative processes of the applied hydrothermal method resulted in different structure and morphology of hexagonal WO 3 nano-crystals. Micro-hotplates with gold electrodes on top to measure sensing layer conductivity were fabricated. WO 3 layers of the two morphologies were deposited using capillary dropping technique. Sensor responses were measured up to 220 °C operation temperature for NH 3 diluted in synthetic air in the 10-100 ppm range. Test results are compared in terms of conductivity, sensitivity and response time.

HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific re... more HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

Microsystem Technologies-micro-and Nanosystems-information Storage and Processing Systems, Oct 3, 2022

Due to their complex electro-thermal characteristics microhotplates used in environmental gas sen... more Due to their complex electro-thermal characteristics microhotplates used in environmental gas sensors require careful design to exhibit uniform temperature and low power dissipation during the expected long time operation. The layout design becomes more complex if the multiple operational parameters required by the battery operation and the driver and readout logic are considered. In this paper, we describe a simple analytical filament design procedure to determine the dimensions of the annular metal filament exhibiting uniform surface temperature without additional heat distribution layer. The presented method operates with the cumulative thermal losses towards the ambient and heat conduction via the membrane. Moreover, it handles the operation requirements like the targeted temperature in the atmospheric environment, supply voltage range, current density, filament layer thickness and its coverage ratio. The efficacy of the method is demonstrated by electrical and thermal characterisation of the manufactured devices having 150 lm diameter active area. The microheater achieves the targeted 500°C operation temperature with 1.4-1.55 V supply. The temperature nonuniformity along the filament was measured by Spectral pyrometry and was found to decrease from ± 3.5% to ± 1% when the temperature was raised from 530 to 830°C.

Chemosensors

A reduced size thermocatalytic gas sensor was developed for the detection of methane over the 20%... more A reduced size thermocatalytic gas sensor was developed for the detection of methane over the 20% of the explosive concentration. The sensor chip is formed from two membranes with a 150 µm diameter heated area in their centers and covered with highly dispersed nano-sized catalyst and inert reference, respectively. The power dissipation of the chip is well below 70 mW at the 530 °C maximum operation temperature. The chip is mounted in a novel surface mounted metal-ceramic sensor package in the form-factor of SOT-89. The sensitivity of the device is 10 mV/v%, whereas the response and recovery times without the additional carbon filter over the chip are <500 ms and <2 s, respectively. The tests have shown the reliability of the new design concerning the hotplate stability and massive encapsulation, but the high degradation rate of the catalyst coupled with its modest chemical power limits the use of the sensor only in pulsed mode of operation. The optimized pulsed mode reduces th...

Microsystem Technologies

Due to their complex electro-thermal characteristics microhotplates used in environmental gas sen... more Due to their complex electro-thermal characteristics microhotplates used in environmental gas sensors require careful design to exhibit uniform temperature and low power dissipation during the expected long time operation. The layout design becomes more complex if the multiple operational parameters required by the battery operation and the driver and readout logic are considered. In this paper, we describe a simple analytical filament design procedure to determine the dimensions of the annular metal filament exhibiting uniform surface temperature without additional heat distribution layer. The presented method operates with the cumulative thermal losses towards the ambient and heat conduction via the membrane. Moreover, it handles the operation requirements like the targeted temperature in the atmospheric environment, supply voltage range, current density, filament layer thickness and its coverage ratio. The efficacy of the method is demonstrated by electrical and thermal character...

Przedmiotem niniejszej pracy jest badanie systemów sterowania robota Robin Heart PVA (ang. Port V... more Przedmiotem niniejszej pracy jest badanie systemów sterowania robota Robin Heart PVA (ang. Port Vision Able) z zastosowaniem specjalnych mikroczujników siły 3D MEMS. Postawiono trzy różne sposoby wykorzystania opracowywanych czujników: (1) jako czujnik siły wykorzystany jako mikrodżojstik zintegrowany w rękojeścią narzędzia endoskopowego, aby łatwo kontrolować ruch robota wizyjnego podczas pracy chirurga; (2) jako czujnik siły wewnątrz szczęki narzędzia endoskopowego dla dostarczenia informacji zwrotnej do operatora-chirurga, mierząc siłę chwytu; (3) jako czujnik wielowymiarowy dotyku na końcu narzędzia chirurgicznego, co ułatwia badanie palpacyjne do diagnostyki tkanek podczas pracy. Artykuł ten jest studium wykonalności w zakresie proponowanych zastosowań. Model sterowania robota przy użyciu prototypowego czujnika siły 3D został pomyślnie przetestowany w badaniach funkcjonalnych robota. Wstępne badania sensorów wykazały ich przydatność dla sterowania robotem ze sprzężeniem siłowym, aby ocenić stan tkanek oraz do oceny siły docisku chirurgicznego chwytaka.

The subject aim of the this work is the inves ga on studying of applicability of 3D MEMS based fo... more The subject aim of the this work is the inves ga on studying of applicability of 3D MEMS based force micro-sensors made by 3D MEMSmicromachining technology and use it as micro-joys ck to control the posi on of robot Robin Heart PVA. Since the robot moves with 5 degrees of freedom to run u lise all the possibili es of movement is done available by the use of the switching clutch control object. By pressing the in appropriate mode (way) the sensor provides the ability to control the func ons of the spherical robot (at diff erent speeds): to lean forward or sideways or alterna vely to penetrate or withdrow withdraw and to rotate of the tool axis is possible. The sensor was fastened in its special of the surgical tool. AnApplicability of appropriate control system equipped with a newthis novel sensor was inves gated in and a comparison with to the control using the classic remote control methodswas invesgated. Preliminary tests of laparoscope integrated force sensors were also inves gat...

Proceedings, 2018

Smart laparoscope device was developed and integrated into the ROBIN HEART surgery robot system. ... more Smart laparoscope device was developed and integrated into the ROBIN HEART surgery robot system. Miniaturised silicon based force sensors were developed and integrated into laparoscope tweezers for the special applications. Different sensors were applied to detect tactile information at the tip of the laparoscope and to measure the clamping force between the tweezers. Preliminary tests were accomplished to evaluate the force and tactile signals of the integrated sensors during interventions. Tactile measurements were implemented on artificial and real animal tissues to prove the applicability of the device for biomechanical screening during Minimal Invasive Surgery.

Microelectronics Reliability, 2017

This work established the correlation between the location of temperature gradients and the posit... more This work established the correlation between the location of temperature gradients and the positions where breakdown is observed on different Pt filament layouts in cantilever and full membrane type micro-hotplates. Focusing on practical aspects like in real operation, self-heating was applied to investigate the limitations of high temperature application and to reveal the fatal failure mechanisms. Besides electromigration, another phenomenon playing dominant role in the breakdown of the filaments, the temperature gradient driven thermomigration of Pt was identified. This limits the local allowable temperature gradient to b0.4°C/μm for operation temperature above 700°C.

Journal of Crystal Growth, 2017

Broad spectrum InGaAsP/InP light emitting heterostructures were grown by low temperature liquid p... more Broad spectrum InGaAsP/InP light emitting heterostructures were grown by low temperature liquid phase epitaxy (LPE). The structure of the LED wafers was investigated by optical transmission measurements, and the layer thicknesses were also measured by electron microscopy. Two quaternary light emitting layers of different composition were built in one device structure in order to broaden the usable wavelength range of the emission spectrum. One of the layers is electrically, whereas the other is optically excited as a result of internal absorption and re-emission of the LED light. As a result of this absorption and re-emission process the modified LED chips have substantially broader emission spectra and higher radiance than the conventional surface emitting multi-wavelength NIR LED structures. The two emission peaks of the spectrum were designed for matching the first and second harmonic wavelength of the fundamental absorption band of C-H bonds. The internal quantum efficiency of the wavelength conversion in this type of LEDs is nearly 100%. Keywords  A1. Optical characterization;  A3. Liquid phase epitaxy;  B1. GaInAsP  B2. Semiconducting III-V materials;  B3. Infrared devices Highlights • New broad spectrum single chip GaInAsP/InP LEDs are prepared. • The broad spectrum LEDs have at least two GaInAs(P) infrared light emitting layers. • Low temperature LPE growth is used for production of the device structures. • Devices are optimized for application in near infrared spectroscopy.

Procedia Engineering, 2016

Various deposition techniques were tested to form Pt catalyst on nano-structured materials charac... more Various deposition techniques were tested to form Pt catalyst on nano-structured materials characterized by 50-200 nm dimensions. Different layer structures applied in gas sensing were sensitized by Pt sputtering and droplet deposition of Pt nanoparticles formed from H2[PtCl6] solutions. Besides, atomic layer deposition (ALD) of Pt was also investigated. The layers to be coated were disordered piles of WO3 nano-rods and sol-gel deposited WO3 nano-crystals as well as electrochemically formed alumina with high aspect ratio perpendicular pores. Distribution of Pt particles inside these layers was analyzed by scanning (SEM) and transmission electron microscopy (TEM). Demonstration of functionality is also provided.

Procedia Engineering, 2016

3D contact force sensors were developed and integrated in a demonstration system for testing the ... more 3D contact force sensors were developed and integrated in a demonstration system for testing the feasibility of their application in minimal invasive surgery (MIS). Piezoresistive MEMS based vectorial force sensors were designed and fabricated by 3D silicon micromachining technology and packaged according to their proposed transducer and sensor applications. In this work we demonstrated the integrability and functional applicability of the 3D force sensors in MIS robotic systems to improve their flexibility and reliability by providing real-time force and tactile information during the operation. The final goal is to integrate the new subsystems in the Robin Heart surgery robot of FRK. [1] Three different functions are targeted: 1. Micro-joystick actuator to be integrated in the hilt of the laparoscope to easily control robotic movement during operation. 2. Force sensor inside the laparoscopic jaw to provide feedback to the surgeon by measuring the grasping strength and 3. 3D force/tactile sensor which facilitates palpation for tissue diagnostics during operation. In this paper we demonstrate a feasibility study regarding these proposed applications.

2016 Symposium on Design, Test, Integration and Packaging of MEMS/MOEMS (DTIP), 2016

1997 International Semiconductor Conference 20th Edition. CAS '97 Proceedings

The application of commercial 3-D software "COSMOS" for the design and thermal analysis of the lo... more The application of commercial 3-D software "COSMOS" for the design and thermal analysis of the low power consumption test structures with dielectric membrane for gas microsensors is presented. Within this work, the simulation provides the estimation of the temperature profile on the active area and thg whole membrane including the four bridges and the heating efficianty in the temperature range 20-5OO0C. Unravelling of the heat loss mechanisms in terms of radiation, convection, conduction by air and solid materials during heat transfer on the dielectric membrane is reported for the first time as a mean to evaluate by 3-D simulation the contribution of technological processes and layout design to the total heat losses.

Nanopages, 2006

The deposition of nanowires for interconnects in nanoelectronic devices were studied morphologica... more The deposition of nanowires for interconnects in nanoelectronic devices were studied morphologically by scanning electron microscopy (SEM), atomic force microscopy (AFM) and by in-situ resistance measurements. The deposition and basic characterization of nanometer size tungsten wires by gas injection (GIS) and focused ion beams (FIB) was carried out in-situ in a LEO 1540 XB workstation. The I(V) measurement showed that the deposited W wires have ohmic characteristic. The variation of the resistance during an ex-situ heating was linear with a low thermal coefficient (4% of the pure metallic W).

Procedia Engineering, 2014

Micro-pellistors capable to detect hydrocarbons below 50 mW power consumption at 550 o C operatio... more Micro-pellistors capable to detect hydrocarbons below 50 mW power consumption at 550 o C operation temperature were developed by a novel processing technique. On the top of the full membrane type micro-heaters 1.4 μm thick porous alumina was formed by laterally selective electrochemical etching of the deposited aluminum layer. The porous alumina of the active element is selectively covered by finely dispersed Pt catalyst using alternative methods; such as dropping of H 2 [PtCl 6 ] and sputtering technique, all aiming at deposition of controlled volume and structure of the catalyst. Constant current method in a Wheatstone-bridge configuration was applied in functional tests.

Sensors and Actuators B: Chemical, 2015

The effect of WO 3 nano-crystal characteristic size and layer morphology on gas sensitive propert... more The effect of WO 3 nano-crystal characteristic size and layer morphology on gas sensitive properties was investigated in order to define the optimum preparation process. WO 3 layers were synthesized by hydrothermal acidic precipitation method using different chemicals and reactive sputtering as reference. Micro-hotplate based conductivity type devices were fabricated and the sensitivity on NH 3 up to 100 ppm was measured in the temperature range of 140-240 • C. The measurements revealed that the characteristic size of the WO 3 nano-crystal plays primary role, but layer morphology opens the way towards extended measuring range. The nano-rod structures operated at 220 • C exhibit the best sensing characteristics in terms of sensitivity and stability over wide range of relative humidity.

Procedia Engineering, 2014

In the past half century the IC technology could produce an unprecedented growth and penetration ... more In the past half century the IC technology could produce an unprecedented growth and penetration into all segments of our daily life due to the achieved extreme productivity and reliability by using well established and continuously refined processing platforms. This uninterrupted trend continued also with the advent of the More than Moore-type MEMS technology allowing the combination of the signal processing capability of the mature IC technology with the exploitation of mechanical, thermal, optical properties of the materials used in IC technology in different sensing and actuation purposes. Mass producibility by monolithic integration required here also the development of appropriate unified set of techniques for the various applications, i.e. sort of standardised platforms to explore. In this paper we focus on the development of bulk micromachined membrane platforms, being exploited in such applications. At the same time this summary also offers a "case study", a retrospective review of the development of

of the main scientific results obtained in the project Background As reported earlier, our indust... more of the main scientific results obtained in the project Background As reported earlier, our industrial partner, who played a fundamental role in the design, construction and servicing of the Solar Cell Technology Innovation Centre installed at MFA was BudaSolar Ltd.. Unfortunately, in 2011 the company went bankrupt. Thereby we lost our technical backup, in the existing apparatus the original co-evaporation concept for all four constituents became in this way obsolete. During the one year suspension of the project permitted by the OTKA Collegium we made efforts to find alternative solutions for the hardware deficiency-related issues.

The structure and composition of multilayered SiN x structures prepared by low pressure chemical ... more The structure and composition of multilayered SiN x structures prepared by low pressure chemical vapour deposition were studied by cross-sectional transmission electron microscopy and spectroscopic ellipsometry. Using appropriate deposition parameters and post deposition annealing, well separated Si nanocrystals were obtained with avarage grain size of 8-10 nm.

Procedia Engineering, 2014

Tungsten oxide nano-powders were prepared by acidic precipitation from sodium tungstate solution.... more Tungsten oxide nano-powders were prepared by acidic precipitation from sodium tungstate solution. The alternative processes of the applied hydrothermal method resulted in different structure and morphology of hexagonal WO 3 nano-crystals. Micro-hotplates with gold electrodes on top to measure sensing layer conductivity were fabricated. WO 3 layers of the two morphologies were deposited using capillary dropping technique. Sensor responses were measured up to 220 °C operation temperature for NH 3 diluted in synthetic air in the 10-100 ppm range. Test results are compared in terms of conductivity, sensitivity and response time.