On December 14, 2023, a distinguished lecture titled “The Basics and Evolution of Organic Devices” was delivered by Prof. Benjamin Iniguez, an IEEE Fellow from URV. The event, organized by Prof. Alexander Kloes and Prof. Mike Schwarz of the Competence Center for Nanotechnology and Photonics (NanoP) at THM – University of Applied Sciences, Germany, drew the participation of 25 attendees.

During the lecture, Prof. Iniguez provided an overview of the historical development of the first Thin-Film Transistor (TFT) devices leading up to the present day. He delved into the details of their properties, benefits, and applications. Subsequently, Prof. Iniguez shifted the focus to Organic Light-Emitting Diode (OLED) devices, offering a historical perspective and discussing the applications and future trends of these devices. The lecture concluded with an overview of Organic Photovoltaic (OPV) devices, covering their current efficiencies in laboratory settings and industrial applications.

Prof. Benjamin Iniguez celebrating the 75 anniversary of the transistor in front of the audience.

This distinguished lecture was part of the celebration of the 75th anniversary of the transistor and showcased one of the many use cases that have emerged over the last few decades. Participants were intrigued by the revelation that the invention of the transistor ultimately paved the way for the development of technologies found in today’s applications.

The EDS Germany Chapter and NanoP proudly presents Benjamin Iniguez from URV, Spain for a Distinguished Lecture on “The Basics and Evolution of Organic Devices”. The lecture will be held on 14th December 2023 at 4pm Berlin time. Interest participants please register via IEEE vTools by the following link: https://events.vtools.ieee.org/m/383286

Benjamin Iniguez Biography: Benjamin Iniguez obtained the Ph D in Physics in 1992 and 1996, respectively, from the Universitat de les Illes Balears (UIB). From February 1997 to September 1998 he was working as a Postdoctoral Researcher at the Rensselaer Polytecnhnic Institute in Troy (NY, USA). From September 1998 to January 2001 he was working as a Postdoctoral Scientist in the Université catholique de Louvain (Louvain-la-Neuve, Belgium), supported by two Marie Curie Fellowships from the European Commission. In February 2001 he joined the Department of Electronic, Electrical and Automatic Control Engineering (DEEEiA) of the Universitat Rovira i Virgili (URV), in Tarragona, Catalonia, Spain) as Titular Professor. In February 2010 he became Full Professor at URV. He obtained the Distinction from the Generalitat for the Promotion of University Research in 2004 and the ICREA Academia Award (the highest award for university professors in Catalonia, from ICREA Institute) in 2009 and 2014, for a period of 5 years each. He led one EU-funded project (“COMON”, 2008-12) devoted to the compact modeling of nanoscale semiconductor devices and he is currently leading one new EU-funded project (DOMINO, 2014-18) targeting the compact modeling of organic and oxide TFTs. His main research interests are the characterization, parameter extraction and compact modelling of emerging semiconductor devices, in particularorganic and oxide Thin-Film Transistors, nanoscale Multi-Gate MOSFETs and GaN HEMTs. He has published more than 150 research papers in international journals and more than 130 abstracts in proceedings of conferences.

The 7th Symposium on Schottky Barrier MOS (SB-MOS) devices was held on September 28/29, 2023 at the Ecole Polytechnique in Palaiseau. It was a joint chapter event organized by the EDS France and Germany Chapter and co-sponsored by Ecole Polytechnique and CNRS. It was attended by approx. 30 participants in presence and hybrid format.

After a short welcome of Dr. Laurie Calvet from CNRS-Ecole Polytechnique (FR) with a detailed schedule, the presentations were started by the chair Kham Niang with an inspiring talk of Dr. Calvet on the topic of “The Schottky barrier transistor in emerging electronic devices”. She reviewed the variety of applications and material systems for over 60 years and introduced the SB transistor. She started with an overview of the device modeling and presented the two large classes of SB devices: 1) those that aim to reduce the Schottky barrier and 2) those that aim to take advantage of it. The talk concluded with a series of questions meant to serve as the starting point for the panel discussion later in the afternoon.

The next talk entitled “Silicon-Germanium Nanosheet Schottky FETs, from Contact Properties to Runtime Reconfigurable Circuit Demonstrators” was given by Prof. Walter Weber, TU Vienna (AT). Prof. Weber offered new insights of Silicon germanium (SixGe1-x). While the Silicon germanium (SixGe1-x) active regions have been intensively investigated for the realization of both bipolar and field effect devices over the past decades, the realization of ultrathin-body SixGe1-x transistors, in particular Schottky contact transistors, with high germanium channel content has been hampered by instabilities of the semiconductor interfaces towards metals and insulators. Prof. Weber discussed the combination of advances in ultra-low-temperature epitaxy, contact- and interface- solid state Al diffusion processes as well as reliable surface passivation measures that allow for the realization of ultrathin SixGe1-xnanosheet Schottky contact FETs being integrated on commercially available silicon-on-insulator substrates. He offered high resolution images of the obtained Schottky SixGe1-x devices with abrupt Al contacts which form a base technology for the realization of future contenders of electronic devices beyond the scope of the industrial roadmaps that profit from the abrupt Schottky junctions and high germanium content. Finally, Prof. Weber showed the possibilities to runtime reconfigurable transistors, neuromorphic devices and cryogenic quantum devices can be realized from the same technological platform.

The symposium continued with “DC Compact Modeling of Schottky Barrier Field-Effect Transistors at Deep Cryogenic Temperatures”. The PhD candidate Christian Römer from THM (DE) discussed Schottky barrier field-effect transistors as candidates for applications at cryogenic temperatures, since its characteristics improve with decreasing temperatures. He presented a physics-based DC compact model to calculate the injection tunneling current through a device’s Schottky barrier. A verification of the compact model was performed by measurements at temperatures around 5 K.

The final part of the first workshop day was the panel discussion on the question “What is the future of Schottky barrier devices?”. At the panel Dr. Calvet, Prof. Weber and PhD candidate Römer offered their opinion and various questions we discussed from different aspects.

Participants of the 7th Symposium on Schottky Barrier MOS (SB-MOS) devices.

The second workshop day was chaired by Prof. Weber and started with the talk entitled “Ferroelectric Schottky barrier transistor for neuromorphic computing” by Prof. Qing-Tai Zhao from the Forschungszentrum Jülich (DE). Prof. Zhao offered the challenges of the slow and ambipolar switching behavior of Schottky barrier MOSFETs which poses certain challenges for logic applications. Nevertheless, during his presentation he explored its potential application in neuromorphic computing when combined with a ferroelectric gate oxide. Prof. Zhao discussed the implementation of artificial synapses and capacitorless neurons using ferroelectric Schottky barrier transistors. By this novel approach he offered advantages for advancing the field of neuromorphic computing.

The next talk was given by Prof. Radu Sporea from University of Surrey (UK). Before he started with the talk of “Recent implementations of source-gated transistors and circuits with high gain”, Prof. Sporea shortly introduced the campus of Surrey where the next Symposium of Schottky Barrier MOS devices will take place. Then he continued with the source-gated transistor (SGT), which one is celebrating 20 years since its invention and presented that some of the more fundamental limitations of these devices have been explored and gradually overcome. The latest advances in exploiting the SGT’s high intrinsic gain, along with a roundup of essential design rules of thumb were offered.

Afterwards, Prof. Alexander Kloes from THM (DE) presented “Evaluation of approaches for analytical calculation of tunneling currents in Schottky barrier transistors”. He explained the different methods to calculate the transmission coefficient in the tunneling equation, explaining why compact modeling of tunneling currents is so challenging. Prof. Kloes reviewed the analytical calculation of a quantum wave based current transport through Schottky barriers that are suitable for compact modeling. He focused on a new promising approach based on the wavelet transform.

“Indium Gallium Zinc Oxide Source-Gated Transistors” by PhD candidate Kham Niang of University of Cambridge (UK) was the next talk. She discussed the use of amorphous oxide semiconductor (AOS) thin film transistors (TFTs)as SGTs. She presented the fabrication and performance of recent IGZO SGTs and discussed in particular the challenges in realizing a Schottky contact between AOS and high work function metal, and presented various methods adopted to mitigate this problem.

The presentations continued with “TCAD simulation studies of source-gated p-type CuO TFTs” by PhD candidate Qi Chen from the Université catholique de Louvain (UCLouvain) (BE). Source-gated p-type CuO TFTs with HfO2 gate dielectric were studied using TCAD tools. Based on parameters extracted from experiments, the gate modulation of the source barrier was investigated varying the thicknesses of CuO and HfO2 and the Schottky barrier height at the source contact. The optimal structure design was further explored to obtain good transconductance and output conductance parameters for circuit design.

Afterwards Prof. Benjamin Iniguez from URV (ES) gave a talk entitled “Compact modeling of the nonlinear contact effects in Organic Thin Film Transistors”. He presented the nonlinear contact effects due to the presence of Schottky barrier at the source-channel interface which may significantly affect the I-V characteristics in Organic Thin Film Transistors. He reviewed four different models that can be used for compact modeling.

The final talk was given by PhD candidate Patryk Golec from University of Surrey (UK). His talk on “A Source-Gated Transistor Compact Model Designed Using TCAD Simulations” offered a compact model developed for a source gated transistor (SGT) using the data obtained from TCAD simulation. He made some fundamental simulation to explain the fundamental different current injection mechanism occurring at the source region. This causes the contact effects to be dominant in the SGT, as opposed to the TFT. With this the resulting compact model of an a-Si SGT describes the changes in device parameters within the source region.

Dr. Laurie Calvet closed the Symposium with some finally remarks, that Schottky barrier junctions offer a wide spectrum of applications and thanked all participants and organizers for realizing this SSBMOS.

On July 3, 2023 Prof. Mike Schwarz from the EDS Germany Chapter and Prof. Ulrich Birkel organized a lecture entitled “Fundamentals of Security Practical Case: Secure Boot of processors”. 33 participants attended the lecture, which was given by Rodrigue Simonneaui, MX FAE from NXP Semiconductors.

Mr. Simonneau started with an introduction and explained the pillars of security. Afterwards, he went through “Building blocks for HW backed security” and offered boundaries with focus on how to compare all hardware enabling depth security components before he target the topic of “Security Architecture across i.MX Processors Family”. In here he gave insights in the i.MX series 6, 7, and 8 and the architecture and devices and how security is enabled at different levels. Afterwards, he move forward to the latest i.MX 93 architecture including RISC-V topology and referred to security enclave aspects.

The secure boot example enabled the students to acquire some processor security fundamentals, illustrated at the end by a live demo. The i.MX93 could first boot a simple signed image, which was in a second step manipulated at the binary level by Mr. Simonneau. The device protected here by mean of ECC signing was able to detect that the imagehas been tampered and thus declined to boot.

Afterwards, the students had the opportunity to ask detailed questions and there were a lot, emphasized by the great demo. The lecture ended after approx. 90 minutes with some conclusions and thanks for the chance to have an experienced engineer of NXP at THM.

Mr. Rodrigue Simonneau explaining the pillars of security.

Prof. Francesca Iacopi, IEEE DL, from the University of Technology Sydney, and Prof. Paul Berger, IEEE DL, from Ohio State University, presented their research with the lectures “Graphene on cubic silicon carbide: integrated functionalities on silicon” and “Si-based Resonant Interband Tunnel Diodes for Quantum Functional and Multi-level Circuitry (Mixed-Signal, Logic, and Low Power Embedded Memory) to Extend CMOS” to the interested audience.

From the beginning, it became clear that the EDS vision, ‘Providing excellence in the field of electron devices for the benefit of humanity’ connects the researchers with the same motivation for their application-oriented research on novel electronic devices.

Starting with a tour at the Institute for Semiconductor and Microsystems Technology, Dr. André Heinzig and Prof. Thomas Mikolajick presented the research on reconfigurable devices and their 2Ddevice activities at the TUD Chair for Nanoelectronics. The research on organic electronic devices was presented in a tour by Dr. Hans Kleemann and Prof. Karl Leo at the Institute of Applied Physics (IAP). The event organization was supported by Sandra Bley from the Center for Advancing Electronics Dresden (cfaed).

Professor Iocapi introduced her distinguished lecture with a look at the fascinating properties of graphene. She pointed out that the consideration has to be differentiated to the application fields of electronics, chemistry, or physics and that in almost all cases, graphene is combined with other materials, which significantly influences its properties. As one of the essential steps for the industrial implementation of graphene, the challenge is providing uniform wafer-scale growth methods. Francesca Iacopis’s achievements in epitaxial graphene growth on SiC demonstrated an impressive result of uniform wafer-scale processing. She continued the topic by presenting charge transfer doping and the characterization of fabricated devices. The formation of buffer layers depending on the crystallization of the SiC exhibited different electrical properties. Impressive achievements in providing patterning techniques with solid sources and catalytic alloys demonstrated additional device design flexibility. The lecture was finalized with a video on applying brain-computer interfaces, e.g., to control robots using the biocompatibility and robustness of epitaxially fabricated Si/SiC/graphene sensors.

Professor Berger began his presentation by introducing Ohio State University and the outstanding individuals and historical developments in electronic devices at this place. After the theoretical background on interband tunnel diodes, he demonstrated ways to reduce circuit complexity, e.g., for oscillators and multivalued logic, using negative differential resistance (NDR) devices instead of conventional transistors. His group’s developments in the field showed impressive results with record peak-to-valley ratios using both epitaxially grown and CVD-grown devices. In particular, the developed delta doping techniques in Si / SiGe structures allow high band bending, enabling efficient band-to-band tunneling of charge carriers resulting in high tunnel currents.

In the subsequent discussion sessions, the interest of the audience in the device topics as well as the expanding potential for the IEEE community became apparent. The guests’ and host groups’ complementary research fields lead to expect a close exchange and cooperation in the development of future electronic devices.

After the lectures, Prof. Berger and Iacopi were hosted by Dr. Kleemann and Prof. Leo at Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP), where they saw recent developments on flexible organic solar cells, printed human-machine interfaces, and polymer-based neuromorphic circuits. Unfortunately, Prof. Iacopi had to head back to the airport in the late afternoon. However, Prof. Berger and Dr. Kleemann used the occasion to continue the discussion and shared anecdotes with a glass of beer in front of the famous Frauenkirche in the scenic heart of Dresden.