Life above 100-GHz: Terahertz device and system challenges and opportunities

• Organisers

  Guillermo Carpintero, Universidad Carlos III de Madrid, Spain
  Dmitry Lyubchenko, KTH Royal Institute of Technology, Sweden

• Subcommittee

  SC9 – Photonics for RF & Free-Space Optics Applications
  SC3 – Photonic Integrated Circuits, Assemblies & Packaging
  

• Day & Time

  18.09.2022, 09:00 – 12:30

• Location

  Room Rio

• Description

  RF Photonic systems handle photonic and electromagnetic waves, being the only technology today enabling continuous generation of Terahertz signals where vast amounts of bandwidth are available. However, as frequencies increase, also increases the complexity of the characterization and packaging of these systems. Current efforts are towards the development of standardized packaging solutions within Packaging Pilot Lines, providing fiber array access ports and multiple DC electrical connections. However, RF applications are still lagging behind, considering that Beyond 5G aiming to move at frequencies above 100 GHz. This is a major problem since there are few RF connector solutions at higher frequencies, with coaxial standards reaching up to 110 GHz (1-mm connector) and rectangular waveguides segmenting the spectrum into bands defined by flange size. In this workshop we will discuss state-of-the-art for characterization and packaging of photonic Terahertz systems.

  This workshop is organized around the TERAmeasure Pathfinder Open EU project (www.uc3m.es/research/terameasure), developing photonic-driven technologies for Terahertz instrumentation. The goal is to develop a photonic-based Vector Network Analyzer operating beyond 1 THz. The workshop provides an overview of why we need these systems, and the current challenges that are faced when developing devices and systems operating above 100 GHz, with key speakers addressing the different components (high-speed photodiodes, detectors), the integration of antennas and the assembly challenges.

• Programme

  Session 1 (90 min, 20 min per speaker)
   Outlook for Beyond 5G communications: Will 100-GHz systems be required?, Atsushi Kanno, National Institute of Information and Communications Technology, Japan
   Demonstrations of THz transmission technology based on photonics for future THz-band indoor network, Seung-Hyun Cho, ETRI, Korea
   Dielectric rod waveguides for ultra-broadband photonic phased array antennas and THz interconnects, Muhsin Ali, Universidad Carlos III de Madrid, Spain
   Broadband PIN-photodiodes and photomixing receivers for photonic THz links, Robert Kohlhaas, Fraunhofer HHI, Germany

  Coffee Break (30 min)

  Session 2 (90 min, 20 min per speaker + 50 min discussion)
   The advancement of THz Test and Measurement equipment for 5G, 6G and beyond, Jeffrey Hesler, Virginia Diodes, USA
   Challenges and demands for wafer-level probing of photonics devices, Dan Rishavy, Form Factor, USA
   Panel discussion

• Speakers

  Speaker 1: Atsushi Kanno, National Institute of Information and Communications Technology, Japan
  Title: Outlook for Beyond 5G communications: Will 100-GHz systems be required?
  Abstract: A broadband communication system in both optical and radio domains will play an important role in the realization of the cyber-physical system, such as the digital twin, in the Beyond 5G era. Terahertz radio access is a promising solution for a throughput higher than 100 Gbit/s for subscribers; however, required data can be transported from the data centers to the radio transceiver station via an optical fiber network. We discuss the overview of the Beyond 5G communication systems with seamless connectivity between photonics and terahertz radios. The required specifications and their applications are also discussed.
  Biography: Atsushi Kanno received B.Sci., M.Sci., and Ph.D. degree in science from the University of Tsukuba, Japan, in 1999, 2001, and 2005, respectively. In 2005, he was with the Venture Business Laboratory of the Institute of Science and Engineering, University of Tsukuba. In 2006, he joined the National Institute of Information and Communications Technology (NICT), Japan. He is a director of Optical Access Technology Laboratory, Photonic ICT Research Center, Network Research Institute, NICT. His research interests are microwave/millimeter-wave/terahertz photonics and optical and radio communication systems. He is a member of the IEICE, the SPIE, and the IEEE.

  Speaker 2: Seung-Hyun Cho, ETRI, Korea
  Title: Demonstrations of THz transmission technology based on photonics for future THz-band indoor network
  Abstract: Recently, research and development projects for 6G have been actively being in progress worldwide. The key services of 6G technology include ultra-realistic extended reality and high-precision mobile holograms, etc. In order to provide these services, it is necessary to transmit wireless data rates beyond 100 Gb/s. To achieve such wireless high-speed data transmission, it is unavoidable to utilize a sub-terahertz frequency band. In this presentation, we would like to introduce a few demonstration systems that transmits high-speed wireless data in sub-terahertz band based on photonics technologies reported by our group so far. In addition, some key factors for the commercialization of sub-terahertz transmission technology will be discussed.
  Biography: Seung-Hyun Cho received his Ph.D. degree in materials science and engineering from Hanyang University, Seoul, Korea, in 2010. From 1999 to 2000, he was with the Access Network Laboratory of Korea Telecom, Daejeon, South Korea. Since 2000, he has been with ETRI, Daejeon, where he is currently a project leader for THz short distance transmission technology based on photonics. His current research interests include next-generation wired and wireless converged networks, indoor network for 6G, and THz wireless delivery systems. He has served as a chair of IEC TC103 since 2019. He has been awarded the Korean Minister of Science and ICT's Citation twice so far. 

  Speaker 3: Jeffrey Hesler, Virginia Diodes, USA
  Title: The advancement of THz Test and Measurement equipment for 5G, 6G and beyond
  Abstract: Measurements of THz devices from single transistors to systems-on-a-chip are crucial to enable rapidly emerging THz applications ranging from imaging to THz communications. This talk will discuss the development of THz test and measurement equipment, with an emphasis on on-wafer testing of THz devices, and the associated challenges. The talk will focus on the generation and detection of broadband signals for use in THz communications (5G/6G), which is needed for channel sounding, the evaluation of 6G waveforms, evaluation of EMV performance, amongst other requirements.
  Biography: Jeffrey Hesler is the Chief Technology Officer of Virginia Diodes, and for more than 25 years he has been working on creating new technologies that utilize the Terahertz frequency band for scientific and commercial applications. He has published over 200 technical papers in journals and international conferences proceedings, is an IEEE Fellow, a member and chair of IEEE Technical Committee MTT-21 (THz Technology and Applications) and a co-Editor of the IEEE Transactions on Terahertz Science and Technology. Terahertz systems based on his designs are used in research laboratories throughout the world.

  Speaker 4: Robert Kohlhaas, Fraunhofer HHI, Germany
  Title: Broadband PIN-photodiodes and photomixing receivers for photonic THz links
  Abstract: Optoelectronic THz systems have the potential to enable wireless, Tbit/s-data rate communication links at carrier frequencies above 100 GHz, possibly even above 1 THz. In addition, the optoelectronic approach allows for direct compatibility with fiber-optical communication systems. This talk will present an overview of the state-of-the-art of optoelectronic THz devices for wireless communication, such as broadband PIN-photodiodes and photomixing receivers, and will give an outlook on current research topics.
  Biography: Robert Kohlhaas received the M.Sc. degree in physics from the Technische Universität Berlin (TUB), Germany, in 2016. Thereafter, he joined the Fraunhofer Institute for Telecommunications, Heinrich Hertz Institute (HHI), as a research associate and project manager. In 2021, he completed his Ph.D. at TUB focusing on photoconductive antennas for terahertz (THz) generation and detection. From July 2022 on, he will head the Terahertz Sensors and Systems Group at Fraunhofer HHI. Active research topics of the group include optoelectronic THz sources and receivers, THz communication links, photonically integrated THz systems, as well as ultrafast photoconductive materials grown by molecular beam epitaxy.

  Speaker 5: Muhsin Ali, Universidad Carlos III de Madrid, Spain
  Title: Dielectric rod waveguides for ultra-broadband photonic phased array antennas and THz interconnects
  Abstract: Continued rise in the data traffic has made millimetre-wave (mmW) and terahertz (THz) a target for developing future communication systems. While significant progress has been made in increasing the cut-off frequency and output power of the photonic/electronic chips, the traditional interconnection and antenna technologies have reached their limits in terms of loss and bandwidth performance. This talk will focus on the dielectric rod waveguide (DRW) technology as a potential emerging solution to these problems. A low-dispersion silicon DRW allows realisation of ultra-broadband and low-loss interconnects and antennas with operational bandwidth of 100s of GHz. Its application to phased arrays and non-contact THz probing will be presented.
  Biography: Muhsin Ali joined Universidad Carlos III de Madrid (UC3M), Spain as a PhD student under the MSCA-ITN project FiWiN5G and earned doctorate in 2020. His research covers the design, fabrication and integration aspects of mm-Wave and THz photonic emitters and electronic detectors for high-speed wireless links with beam-steering capabilities aimed at beyond 5G systems. He worked as a Visiting Researcher at Fraunhofer Heinrich Hertz Institute (HHI) Berlin in 2019 and University of Duisburg-Essen in 2021. Since 2020, he has been a postdoc where he focuses on designing THz dielectric waveguides and phased array antennas for the applications in instrumentation, sensing and wireless systems.

  Speaker 6: Dan Rishavy, Form Factor, USA
  Title: Challenges and demands for wafer-level probing of photonics devices
  Abstract: The integration of optical components on a chip creates a host of new challenges and demands for wafer-level probing of photonics devices, where huge volumes of device-performance data are required to carry a design from concept to qualification and into production. While working in a lab on an initial prototype, it may suffice to spend minutes or in some cases hours to setup and align a single device for measurements. However, such time- and effort-intensive methods are unsuitable for the cycle-time demands of volume SiPh manufacturing.
  Due to the industry demand for a wide range of applications, a flexible probing platform is needed that can be quickly optimized for the needs of the application.
  Numerous parameters can be configured on FormFactor’s wafer probers to enable optical, RF, DC, wafer level, die level, surface coupling, edge coupling, and probe cards. In the talk we will discus how these various test approaches are carried out and how the necessary calibrations are achieved while maintaining the required alignment performance requirements in terms of accuracy, throughput, and power coupling repeatability.
  Come to this session to learn more about FormFactor’s exciting technology enabling the Silicon Photonics market expansion.
  Biography: Dan Rishavy is a Director of Market Development for FormFactor’s systems business unit. Dan holds a degree in Electrical Engineering from the University of South Florida and an MBA from West Texas A&M University. He has been working in various aspects of the Semiconductor Test and wafer probing industry for over 20 years. Dan has held variety of roles in applications, product management and marketing throughout his career at Hewlett Packard, Agilent, Verigy, Tokyo Electron, Cascade Microtech, and Form Factor.