@article{WernerMiyamotoWagneretal.2017, author = {Werner, Frederik and Miyamoto, Ko-ichiro and Wagner, Torsten and Sch{\"o}ning, Michael Josef and Yoshinobu, Tatsuo}, title = {Lateral resolution enhancement of pulse-driven light-addressable potentiometric sensor}, series = {Sensor and Actuators B: Chemical}, volume = {248}, journal = {Sensor and Actuators B: Chemical}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0925-4005}, doi = {10.1016/j.snb.2017.02.057}, pages = {961 -- 965}, year = {2017}, abstract = {To study chemical and biological processes, spatially resolved determination of the concentrations of one or more analyte species is of distinct interest. With a light-addressable potentiometric sensor (LAPS), chemical images can be created, which visualize the concentration distribution above the sensor plate. One important challenge is to achieve a good lateral resolution in order to detect events that take place in a small and limited region. LAPS utilizes a focused light spot to address the measurement region. By moving this light spot along the semiconductor sensor plate, the concentration distribution can be observed. In this study, we show that utilizing a pulse as light excitation instead of a traditionally used continuously modulated light excitation, the lateral resolution can be improved by a factor of 6 or more.}, language = {en} } @inproceedings{MiyamotoSutoWerneretal.2017, author = {Miyamoto, Ko-ichiro and Suto, Takeyuki and Werner, Frederik and Wagner, Torsten and Sch{\"o}ning, Michael Josef and Yoshinobu, Tatsuo}, title = {Restraining the Diffusion of Photocarriers to Improve the Spatial Resolution of the Chemical Imaging Sensor}, series = {MDPI Proceedings}, volume = {1}, booktitle = {MDPI Proceedings}, number = {4}, doi = {10.3390/proceedings1040477}, pages = {4 Seiten}, year = {2017}, language = {en} } @article{MiyamotoSekiSutoetal.2018, author = {Miyamoto, Koichiro and Seki, Kosuke and Suto, Takeyuki and Werner, Frederik and Wagner, Torsten and Sch{\"o}ning, Michael Josef and Yoshinobu, Tatsuo}, title = {Improved spatial resolution of the chemical imaging sensor with a hybrid illumination that suppresses lateral diffusion of photocarriers}, series = {Sensor and Actuators B: Chemical}, volume = {273}, journal = {Sensor and Actuators B: Chemical}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0925-4005}, doi = {10.1016/j.snb.2018.07.016}, pages = {1328 -- 1333}, year = {2018}, abstract = {The chemical imaging sensor is a semiconductor-based chemical sensor capable of visualizing pH and ion distributions. The spatial resolution depends on the lateral diffusion of photocarriers generated by illumination of the semiconductor substrate. In this study, two types of optical setups, one based on a bundle of optical fibers and the other based on a binocular tube head, were developed to project a hybrid illumination of a modulated light beam and a ring-shaped constant illumination onto the sensor plate. An improved spatial resolution was realized by the ring-shaped constant illumination, which suppressed lateral diffusion of photocarriers by enhanced recombination due to the increased carrier concentration.}, language = {en} } @article{YoshinobuSchoening2021, author = {Yoshinobu, Tatsuo and Sch{\"o}ning, Michael Josef}, title = {Light-addressable potentiometric sensors (LAPS) for cell monitoring and biosensing}, series = {Current Opinion in Electrochemistry}, journal = {Current Opinion in Electrochemistry}, number = {In Press, Journal Pre-proof}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2451-9103}, doi = {10.1016/j.coelec.2021.100727}, year = {2021}, language = {en} } @inproceedings{SchoeningAbouzarWagneretal.2006, author = {Sch{\"o}ning, Michael Josef and Abouzar, Maryam H. and Wagner, Torsten and N{\"a}ther, Niko and Rolka, David and Yoshinobu, Tatsuo and Kloock, Joachim P. and Turek, Monika and Ingebrandt, Sven and Poghossian, Arshak}, title = {A semiconductor-based field-effect platform for (bio-)chemical and physical sensors: From capacitive EIS sensors and LAPS over ISFETs to nano-scale devices}, series = {MRS Proceedings}, booktitle = {MRS Proceedings}, doi = {10.1557/PROC-0952-F08-02}, pages = {1 -- 9}, year = {2006}, language = {en} } @article{PoghossianYoshinobuSimonisetal.2001, author = {Poghossian, Arshak and Yoshinobu, Tatsuo and Simonis, A. and Ecken, H. and L{\"u}th, Hans and Sch{\"o}ning, Michael Josef}, title = {Penicillin detection by means of field-effect based sensors: EnFET, capacitive EIS sensor or LAPS?}, series = {Sensors and Actuators B. 78 (2001), H. 1-3}, journal = {Sensors and Actuators B. 78 (2001), H. 1-3}, isbn = {0925-4005}, pages = {237 -- 242}, year = {2001}, language = {en} } @article{PoghossianYoshinobuSchoening2003, author = {Poghossian, Arshak and Yoshinobu, Tatsuo and Sch{\"o}ning, Michael Josef}, title = {Flow-velocity microsensors based on semiconductor field-effect structures}, series = {Sensors. 3 (2003), H. 7}, journal = {Sensors. 3 (2003), H. 7}, isbn = {1424-8220}, pages = {202 -- 212}, year = {2003}, language = {en} } @incollection{YoshinobuKrauseMiyamotoetal.2018, author = {Yoshinobu, Tatsuo and Krause, Steffi and Miyamoto, Ko-ichiro and Werner, Frederik and Poghossian, Arshak and Wagner, Torsten and Sch{\"o}ning, Michael Josef}, title = {(Bio-)chemical Sensing and Imaging by LAPS and SPIM}, series = {Label-free biosensing: advanced materials, devices and applications}, booktitle = {Label-free biosensing: advanced materials, devices and applications}, publisher = {Springer}, address = {Cham}, isbn = {978-3-319-75219-8}, pages = {103 -- 132}, year = {2018}, abstract = {The light-addressable potentiometric sensor (LAPS) and scanning photo-induced impedance microscopy (SPIM) are two closely related methods to visualise the distributions of chemical species and impedance, respectively, at the interface between the sensing surface and the sample solution. They both have the same field-effect structure based on a semiconductor, which allows spatially resolved and label-free measurement of chemical species and impedance in the form of a photocurrent signal generated by a scanning light beam. In this article, the principles and various operation modes of LAPS and SPIM, functionalisation of the sensing surface for measuring various species, LAPS-based chemical imaging and high-resolution sensors based on silicon-on-sapphire substrates are described and discussed, focusing on their technical details and prospective applications.}, language = {en} } @article{SchoeningPoghossianYoshinobuetal.2001, author = {Sch{\"o}ning, Michael Josef and Poghossian, Arshak and Yoshinobu, Tatsuo and L{\"u}th, Hans}, title = {Semiconductor-based field-effect structures for chemical sensing}, pages = {188 -- 198}, year = {2001}, language = {en} } @inproceedings{WernerSpelthahnSchoeningetal.2010, author = {Werner, Frederik and Spelthahn, Heiko and Sch{\"o}ning, Michael Josef and Krumbe, Christoph and Wagner, Torsten and Yoshinobu, Tatsuo and Keusgen, Michael}, title = {Neue Ansteuerungselektronik f{\"u}r LAPS-basierte Biosensoren zur gleichzeitig ortsaufgel{\"o}sten Messung der pH-Konzentration}, series = {Tagungsband: Sensoren und Messsysteme 2010}, booktitle = {Tagungsband: Sensoren und Messsysteme 2010}, publisher = {VDE Verlag}, address = {Berlin}, isbn = {978-3-8007-3260-9}, pages = {109 -- 114}, year = {2010}, abstract = {Ein lichtadressierbarer potentiometrischer Sensor (LAPS) kann die Konzentration eines oder mehrerer Analyten ortsaufgel{\"o}st auf der Sensoroberfl{\"a}che nachweisen. Dazu wird mit einer modulierten Lichtquelle die Halbleiterstruktur des zu untersuchenden Bereiches angeregt und ein entsprechender Photostrom ausgelesen. Durch gleichzeitige Anregung mehrere Bereiche durch Lichtquellen mit unterschiedlichen Modulationsfrequenzen k{\"o}nnen diese auch zeitgleich ausgelesen werden. Mit der neuen, hier vorgestellten Ansteuerungselektronik integriert in einem "Field Programmable Gate Array" (FPGA) ist es m{\"o}glich, mehrere Leuchtquellen gleichzeitig mit unterschiedlichen, w{\"a}hrend der Laufzeit festlegbaren Frequenzen, Phasen und Lichtintensit{\"a}ten zu betreiben. Somit kann das Frequenzverhalten des Sensors untersucht und die Konzentration des Analyten {\"u}ber das Oberfl{\"a}chenpotential mit Hilfe von Strom/Spannungs-Kurven und Phase/Spannungs-Kurven bestimmt werden.}, language = {de} }