Encapsulation and dielectric interfaces
This workshop, hosted by the Graphene Flagship's 2D-EPL, will take place on 19 May 2022, 15:00-17:00 CEST. We will examine encapsulation and dielectric interfaces in the integration of 2D materials for the semiconductor industry. Registration is free and now OPEN!
Prof. Tibor Grasser is an IEEE Fellow and head of the Institute for Microelectronics at TU Wien. He has edited various books, e.g. on the bias temperature instability, hot carrier degradation, and low-frequency noise (all with Springer), is a distinguished lecturer of the IEEE EDS, has been involved in outstanding conferences such as IEDM (General Chair 2021), IRPS, SISPAD, ESSDERC, and IIRW, is a recipient of the Best and Outstanding Paper Awards at IRPS (2008, 2010, 2012, and 2014), IPFA (2013 and 2014), ESREF (2008) and the IEEE EDS Paul Rappaport Award (2011). He currently serves as an Associate Editor for IEEE T-ED, following his assignment with Microelectronics Reliability (Elsevier).
Dr. Gordon Rinke obtained his PhD in Materials Science from the EPFL Lausanne, Switzerland in 2013. After spending over 6 years in industry for a semiconductor tool manufacturer as lead process engineer, he joined AMO GmbH in Aachen, Germany in 2021 as Project Manager for the European 2D Experimental Pilot Line Project and became deputy of the graphene electronics group. His background covers the nanostructure growth and fabrication of organic and inorganic materials as well as process development and optimization.
Dr Harm Knoops is the Atomic Scale Segment Specialist at Oxford Instruments Plasma Technology and holds a part-time assistant professorship position at the Eindhoven University of Technology. His work covers the fields of (plasma-based) synthesis of thin films, advanced diagnostics and understanding and developing plasma ALD, plasma ALE and growth of 2D materials. His main goals are to improve and advance atomic scale processes and applications for Oxford Instruments and its customers.
Ageeth Bol is Professor of Chemistry and Applied Physics at the University of Michigan - Ann Arbor, MI. She received her MSc and PhD in Chemistry from Utrecht University. After obtaining her PhD in 2001 she worked for Philips Electronics and at the IBM TJ Watson Research Center in the USA. From 2011 to 2021 she was Professor of Applied Physics at Eindhoven University of Technology, the Netherlands. Ageeth received in 2014 a prestigious Consolidator Grant by the European Research Council. In 2019 she was a awarded a VICI grant from the NWO (Netherlands Organization for Scientific Research). She published over 100 papers and holds 19 patents. Her current research interests include the fabrication, modification and integration of 1-D and 2-D nanomaterials for (opto)electronics and sustainable energy technology using atomic layer deposition and chemical vapor deposition.
Dr Ravi Sundaram is the Head of strategic R&D Markets at Oxford Instruments Plasma Technology responsible for leading the market strategy and collaborative R&D activity globally. He has been involved in materials research in several institutions such as EPFL, Switzerland, Max Planck Institute Stuttgart, Germany, IBM T.J Watson Research Labs, NY and Cambridge University where he worked on several aspects of 1D and 2D materials-based research from synthesis, fundamental science to prototype applications in sensors, optoelectronics and electronics. He joined Oxford Instruments to lead and coordinate R&D efforts towards 2D materials products. Currently, he is responsible for strategy and business development in key R&D markets such as Quantum Technologies, 2D materials, biomedical devices, integrated photonics among others.
15:00 - 15:15 | Gordon Rinke, AMO
2D Experimental Pilot Line update. Announcing the call for applications to participate in the 2D-Experimental Pilot Line's first Multi-Project Wafer (MPW) run.
15:15 - 16:00 | Tibor Grasser, TU Wien
The Quest for the Perfect Insulator for 2D Materials
Despite the breathtaking progress already achieved for 2D electronic devices, they are still far from exploiting their predicted performance potential. This is in part due to the lack of scalable insulators, which would go along with 2D materials as nicely as SiO2 goes with silicon. As a result, there is still no commercially competitive 2D transistor technology available today.
The selection of suitable insulators for 2D nanoelectronics represents an enormous challenge. However, this problem is of key importance, since scaling of 2D semiconductors towards sub-10nm channel lengths is only possible with gate insulators scalable down to sub-1nm equivalent oxide thicknesses (EOT). In order to achieve competitive device performance, these insulators need to meet stringent requirements regarding (i) low gate leakage currents, (ii) low density of interface traps, (iii) low density of border insulator traps and (iv) high dielectric strength.
The insulators typically used for 2D electronic devices are amorphous 3D oxides known from Si technologies (SiO2, HfO2, Al2O3), while native 2D oxides (MO3, WO3 and Bi2SeO5), layered 2D crystals (hBN, mica) and ionic 3D crystals (CaF2 and other fluorides like SrF2, MgF2) have received increasing attention. 3D oxides form poor quality interfaces with 2D semiconductors and contain border traps which severely perturb stable device operation. Native oxides, on the other hand, are often non-stoichiometric due to the lack of well-adjusted oxidation methods and thus have a limited dielectric stability and inherently narrow bandgaps. As the most popular candidate, the layered 2D insulator hBN forms excellent van der Waals interfaces with 2D semiconductors, but has mediocre dielectric properties resulting in excessive leakage currents for sub-1nm EOT. The potential of other 2D insulators (e.g. mica) is currently unclear, in part due to the absence of scalable growth techniques. Finally, very promising insulators for 2D electronics are 3D ionic crystals like CaF2 which form well-defined interfaces to 2D channel materials. In contrast to hBN, fluorides have good dielectric properties and thus exhibit low gate leakage currents. This talk will address the current state of the art and summarize the main problems together with potential solutions.
16:00 - 16:30 | Harm Knoops, Oxford Instruments
Damage-free plasma ALD on graphene: enabled by in-situ-prepared protective seed layer
A key challenge to realising graphene’s potential in emerging electronics and optoelectronics is the development of scalable, high-quality integration of dielectric materials as functional layers and encapsulation. We describe a novel method to deposit high-κ dielectrics on graphene through an in-situ-prepared protective seed-layer using the Oxford Instruments Atomfab system. For the development of graphene-based devices, such as transistors, photodetectors, or optical modulators, a deposition of a high-quality dielectric film on graphene is required. However, this deposition is challenging because nucleation on pristine graphene is difficult. While defect induced nucleation, for example through plasma exposure, improves nucleation, it also decreases the quality of the graphene layer. Recently we reported dielectric deposition using remote plasma ALD, without observable damage, by protecting the graphene by hexagonal boron nitride (hBN). However, using hBN involves additional transfer processes, which may complicate the fabrication and introduce contamination, defects, and wrinkles. Inspired by this process, we developed a new process using an in-situ deposited seed-layer to protect the graphene effectively, enabling plasma assisted deposition of Al2O3 without damaging the graphene.
16:25 - 16:55 | Panel Discussion
Our speakers will continue the discussion encapsulation and dielectric interfaces in the integration of 2D materials for the semiconductor indus. The panel will be open to your questions relating to the previous presentations or other related topics.
Moderator: Ravi Sundaram, Oxford Instruments
16:55 - 17:00 | Closing thoughts