@unpublished{SteglichRabusSadaetal.2021, author = {Steglich, Patrick and Rabus, Dominik G. and Sada, Cinzia and Paul, Martin and Weller, Michael G. and Mai, Christian and Mai, Andreas}, title = {Silicon Photonic Micro-Ring Resonators for Chemical and Biological Sensing: A Tutorial}, series = {TechRxiv}, journal = {TechRxiv}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-16840}, year = {2021}, abstract = {Silicon photonic micro-ring resonators (MRR) developed on the silicon-on-insulator (SOI) platform, owing to their high sensitivity and small footprint, show great potential for many chemical and biological sensing applications such as label-free detection in environmental monitoring, biomedical engineering, and food analysis. In this tutorial, we provide the theoretical background and give design guidelines for SOI-based MRR as well as examples of surface functionalization procedures for label-free detection of molecules. After introducing the advantages and perspectives of MRR, fundamentals of MRR are described in detail, followed by an introduction to the fabrication methods, which are based on a complementary metal-oxide semiconductor (CMOS) technology. Optimization of MRR for chemical and biological sensing is provided, with special emphasis on the optimization of waveguide geometry. At this point, the difference between chemical bulk sensing and label-free surface sensing is explained, and definitions like waveguide sensitivity, ring sensitivity, overall sensitivity as well as the limit of detection (LoD) of MRR are introduced. Further, we show and explain chemical bulk sensing of sodium chloride (NaCl) in water and provide a recipe for label-free surface sensing.}, language = {en} } @article{MaiMaiSteglich2022, author = {Mai, Andreas and Mai, Christian and Steglich, Patrick}, title = {From Lab-on-chip to Lab-in-App: Challenges towards silicon photonic biosensors product developments}, series = {Results in Optics}, volume = {9}, journal = {Results in Optics}, publisher = {Elsevier}, issn = {2666-9501}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-16687}, year = {2022}, abstract = {This work presents and evaluates different approaches of integrated optical sensors based on photonic integrated circuit (PIC) technologies for refractive index sensing. Bottlenecks in the fabrication flow towards an applicable system are discussed that hinder a cost-effective mass-production for disposable sensor chips. As sensor device, a waveguide coupled micro-ring based approach is chosen which is manufactured in an 8" wafer level process. We will show that the co-integration with a reproducible, scalable and low-cost microfluidic interface is the main challenge which needs to be overcome for future application of silicon technology based PIC sensor chips.}, language = {en} } @article{SteglichMaiVillringeretal.2020, author = {Steglich, Patrick and Mai, Christian and Villringer, Claus and Mai, Andreas}, title = {Direct observation and simultaneous use of linear and quadratic electro-optical effects}, series = {Journal of Physics D: Applied Physics}, volume = {53}, journal = {Journal of Physics D: Applied Physics}, number = {12}, issn = {1361-6463}, doi = {10.1088/1361-6463/ab6059}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-13032}, year = {2020}, abstract = {We report on the direct observation and simultaneous use of the linear and quadratic electro-optical effect and propose a method by which higher-order susceptibilities of electro-optical materials can be determined. The evaluation is based on the separation of the second- and third-order susceptibilities and the experimental technique uses a slot waveguide ring resonator fabricated in integrated photonic circuit technology, which is embedded by a guest-host polymer system consisting of the azobenzene dye Disperse Red 1 in a poly(methyl methacrylate) matrix as an active electro-optical material. The contribution of both effects on the electro-optical response under the influence of static and time-varying electrical fields is investigated. We show that the quadratic electro-optical effect has a significant influence on the overall electro-optical response even with acentric molecular orientated molecules. Our findings have important implications for developing electro-optical devices based on polymer-filled slot waveguides and give rise to advanced photonic circuits.}, language = {en} } @article{SteglichVillringerDietzeletal.2019, author = {Steglich, Patrick and Villringer, Claus and Dietzel, Birgit and Mai, Christian and Schrader, Sigurd and Casalboni, Mauro and Mai, Andreas}, title = {On-Chip Dispersion Measurement of the Quadratic Electro-Optic Effect in Nonlinear Optical Polymers Using a Photonic Integrated Circuit Technology}, series = {IEEE Photonics Journal}, volume = {11}, journal = {IEEE Photonics Journal}, number = {3}, issn = {1943-0655}, doi = {10.1109/JPHOT.2019.2917665}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-12307}, year = {2019}, abstract = {A novel method to determine the dispersion of the quadratic electro-optic effect in nonlinear optical materials by using a silicon-on-insulator microring resonator is presented. The microring consists of a silicon slot waveguide enabling large dc electric field strength at low applied voltages. The dispersion of third-order hyperpolarizability of a linear conjugated dye is approximated by using a two-level model for the off-resonant spectral region. As an example, the dispersion of the resonance wavelength of the resonator filled with a dye doped polymer was measured in dependence of the applied dc voltage. The polymer was poly (methylmethacrylate) doped with 5 wt\% disperse red 1 (DR1), and the measurements have been carried out at the telecommunication wavelength band around 1550 nm (optical C-band). The described measurements represent a new technique to determine the dispersion of the third-order susceptibility and molecular hyperpolarizability of the material filled into the slot of the ring-resonator.}, language = {en} } @article{SteglichMaiVillringeretal.2018, author = {Steglich, Patrick and Mai, Christian and Villringer, Claus and Pulwer, Silvio and Casalboni, Mauro and Schrader, Sigurd and Mai, Andreas}, title = {Quadratic electro-optic effect in silicon-organic hybrid slot-waveguides}, series = {Optics Letters}, volume = {43}, journal = {Optics Letters}, number = {15}, issn = {1539-4794}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-12148}, year = {2018}, abstract = {This Letter reports on the quadratic electro-optic effect of polymers, observed in a silicon slot-waveguide at low voltages. We demonstrate that in narrow slots, the electro-optic response with respect to refractive index change is strong enough for on-chip wavelength tuning and intensity modulation using voltages as low as 1 V. A silicon slot-waveguide embedded by a nonlinear optical polymer, consisting of the dye Disperse Red 1 in poly(methyl methacrylate), serves as the phase shifter in a racetrack ring resonator. As deduced from the experimental data, the third-order susceptibility of the utilized electro-optic polymer is about 2·10-19 m2/V2. The demonstrated low-voltage operation and inherently thermal stability show the potential for silicon-organic hybrid devices using the quadratic electro-optic effect.}, language = {en} } @article{SteglichMaiVillringeretal.2021, author = {Steglich, Patrick and Mai, Christian and Villringer, Claus and Dietzel, Birgit and Bondarenko, Siegfried and Ksianzou, Viachaslau and Villasmunta, Francesco and Zesch, Christoph and Pulwer, Silvio and Burger, Martin and Bauer, Joachim and Heinrich, Friedhelm and Schrader, Sigurd and Vitale, Francesco and De Matteis, Fabio and Prosposito, Paolo and Casalboni, Mauro and Mai, Andreas}, title = {Silicon-organic hybrid photonics: an overview of recent advances, electro-optical effects and CMOS integration concepts}, series = {Journal of Physics: Photonics}, volume = {3}, journal = {Journal of Physics: Photonics}, number = {2}, issn = {2515-7647}, doi = {10.1088/2515-7647/abd7cf}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-13882}, year = {2021}, abstract = {In recent decades, much research effort has been invested in the development of photonic integrated circuits, and silicon-on-insulator technology has been established as a reliable platform for highly scalable silicon-based electro-optical modulators. However, the performance of such devices is restricted by the inherent material properties of silicon. An approach to overcoming these deficiencies is to integrate organic materials with exceptionally high optical nonlinearities into a silicon-on-insulator photonic platform. Silicon-organic hybrid photonics has been shown to overcome the drawbacks of silicon-based modulators in terms of operating speed, bandwidth, and energy consumption. This work reviews recent advances in silicon-organic hybrid photonics and covers the latest improvements to single components and device concepts. Special emphasis is given to the in-device performance of novel electro-optical polymers and the use of different electro-optical effects, such as the linear and quadratic electro-optical effect, as well as the electric-field-induced linear electro-optical effect. Finally, the inherent challenges of implementing non-linear optical polymers on a silicon photonic platform are discussed and a perspective for future directions is given.}, language = {en} } @inproceedings{SteglichPaulMaietal.2021, author = {Steglich, Patrick and Paul, Martin and Mai, Christian and B{\"o}hme, Andrea and Bondarenko, Siegfried and Weller, Michael G. and Mai, Andreas}, title = {A monolithically integrated micro fluidic channel in a silicon-based photonic-integrated-circuit technology for biochemical sensing}, series = {Proc. SPIE 11772, Optical Sensors 2021}, booktitle = {Proc. SPIE 11772, Optical Sensors 2021}, doi = {10.1117/12.2588791}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-13925}, year = {2021}, abstract = {In this work, a cost-effective optofluidic system is propossed and preliminary experimental results are presented. A microfluidic channel monolithically integrated into a photonic integrated circuit technology is used in conjunc- tion with a cyclo-olefin copolymer (COC) substrate to provide fluidic in- and output ports. We report on initial experimental results as well as on the simple and cost-effective fabrication of this optofluidic system by means of micro-milling.}, language = {en} } @article{SteglichBondarenkoMaietal.2020, author = {Steglich, Patrick and Bondarenko, Siegfried and Mai, Christian and Paul, Martin and Weller, Michael G. and Mai, Andreas}, title = {CMOS-Compatible Silicon Photonic Sensor for Refractive Index Sensing Using Local Back-Side Release}, series = {IEEE Photonics Technology Letters}, volume = {32}, journal = {IEEE Photonics Technology Letters}, number = {19}, issn = {1941-0174}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-13649}, pages = {1241 -- 1244}, year = {2020}, abstract = {Silicon photonic sensors are promising candidates for lab-on-a-chip solutions with versatile applications and scalable production prospects using complementary metal-oxide semiconductor (CMOS) fabrication methods. However, the widespread use has been hindered because the sensing area adjoins optical and electrical components making packaging and sensor handling challenging. In this work, a local back-side release of the photonic sensor is employed, enabling a separation of the sensing area from the rest of the chip. This approach allows preserving the compatibility of photonic integrated circuits in the front-end of line and metal interconnects in the back-end of line. The sensor is based on a micro-ring resonator and is fabricated on wafer-level using a CMOS technology. We revealed a ring resonator sensitivity for homogeneous sensing of 106 nm/RIU.}, language = {en} } @article{KalishettyhalliMahadevaiahPerezLiskeretal.2022, author = {Kalishettyhalli Mahadevaiah, Mamathamba and Perez, Eduardo and Lisker, Marco and Schubert, Markus Andreas and Perez-Bosch Quesada, Emilio and Wenger, Christian and Mai, Andreas}, title = {Modulating the Filamentary-Based Resistive Switching Properties of HfO₂ Memristive Devices by Adding Al₂O₃ Layers}, series = {Electronics}, volume = {11}, journal = {Electronics}, number = {10}, address = {MDPI}, issn = {2079-9292}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-16172}, year = {2022}, abstract = {The resistive switching properties of HfO₂ based 1T-1R memristive devices are electrically modified by adding ultra-thin layers of Al₂O₃ into the memristive device. Three different types of memristive stacks are fabricated in the 130 nm CMOS technology of IHP. The switching properties of the memristive devices are discussed with respect to forming voltages, low resistance state and high resistance state characteristics and their variabilities. The experimental I-V characteristics of set and reset operations are evaluated by using the quantum point contact model. The properties of the conduction filament in the on and off states of the memristive devices are discussed with respect to the model parameters obtained from the QPC fit.}, language = {en} } @incollection{KalishettyhalliMahadevaiahLiskerFraschkeetal.2024, author = {Kalishettyhalli Mahadevaiah, Mamathamba and Lisker, Marco and Fraschke, Mirko and Marschmeyer, Steffen and Perez, Eduardo and Perez-Bosch Quesada, Emilio and Wenger, Christian and Mai, Andreas}, title = {Integration of Memristive Devices into a 130 nm CMOS Baseline Technology}, series = {Bio-Inspired Information Pathways: From Neuroscience to Neurotronics}, booktitle = {Bio-Inspired Information Pathways: From Neuroscience to Neurotronics}, editor = {Ziegler, Martin and Mussenbrock, Thomas and Kohlstedt, Hermann}, publisher = {Springer International Publishing}, address = {Cham}, isbn = {978-3-031-36705-2}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-18029}, publisher = {Technische Hochschule Wildau}, pages = {177 -- 190}, year = {2024}, abstract = {The two main features of the memristive devices which makes them the promising candidates for neuromorphic applications are low power consumption and CMOS compatibility. The monolithic integration of memristive devices with CMOS circuitry paves the way for in-memory computing. This chapter focuses on the factors governing the CMOS integration process. Firstly, the influence of CMOS baseline technology selection on the memristor module is briefly discussed. Secondly, the selection of metal level interconnects and their effect on the memristive device performance is explained. Further, the widely used deposition technique for the CMOS compatible memristive switching layers is presented. Finally, the implementation of the optimized process for the fabrication of the memristive module and its influence on the device performance is presented in terms of electrical characterization results.}, language = {en} } @inproceedings{SteglichMaiStolareketal.2016, author = {Steglich, Patrick and Mai, Christian and Stolarek, David and Lischke, Stefan and Kupijai, Sebastian and Villringer, Claus and Pulwer, Silvio and Heinrich, Friedhelm and Bauer, Joachim and Meister, Stefan and Knoll, Dieter and Casalboni, Mauro and Schrader, Sigurd}, title = {Partially slotted silicon ring resonator covered with electro-optical polymer}, series = {Proceedings of SPIE}, booktitle = {Proceedings of SPIE}, issn = {1996-756X}, doi = {10.1117/12.2217725}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-13771}, year = {2016}, abstract = {In this work, we present for the first time a partially slotted silicon ring resonator (PSRR) covered with an electro-optical polymer (Poly[(methyl methacrylate)-co-(Disperse Red 1 acrylate)]). The PSRR takes advantage of both a highly efficient vertical slot waveguide based phase shifter and a low loss strip waveguide in a single ring. The device is realized on 200 mm silicon-on-insulator wafers using 248 nm DUV lithography and covered with the electro-optic polymer in a post process. This silicon-organic hybrid ring resonator has a small footprint, high optical quality factor, and high DC device tunability. A quality factor of up to 105 and a DC device tunability of about 700 pm/V is experimentally demonstrated in the wavelength range of 1540 nm to 1590 nm. Further, we compare our results with state-of-the-art silicon-organic hybrid devices by determining the poling efficiency. It is demonstrated that the active PSRR is a promising candidate for efficient optical switches and tunable filters.}, language = {en} }