Ultra-doped semiconductors made by non-equilibrium processing for electronic, photonic and spintronic applications II

Doping is the key to making semiconductors functional. Ultra-doping or Hyperdoping refers to introducing dopant concentrations far above the solid solubility limits. This leads to the broadening of dopant energy level into a separated or merged impurity band with interesting consequences in terms of (opto)electronic, magnetic or superconducting properties.

Scope:

In 1931, Wolfgang Pauli said “One shouldn’t work on semiconductors, that is a filthy mess; who knows whether any semiconductors exist”. We know it is doping that makes semiconductor exist and functional. Doping is the intentional introduction of impurities into an intrinsic semiconductor for the purpose of modulating its electrical, optical and structural properties. It is the indispensable step in the integrated-circuit industry production line. The ultra-doping or hyperdoping of semiconductors refers to introducing dopant concentrations far above the solid solubility limits. This leads to the broadening of dopant energy level into a separated or merged impurity band with interesting consequences in terms of optoelectronic, magnetic or superconducting properties. Here, the dopants also include those elements that are far away from the host semiconductor in the element table and have large ionization energies. By hyperdoping, semiconductors can be turned to metals, superconductors (such as boron doped diamond/Si/Ge), or ferromagnets (such as Mn doped III-V compounds). The applications spread from electronics, spintronics, quantum technology to optoelectronics, with the first practical devices appearing recently. To overcome the solid solubility limit, methods far away from thermal equilibrium, such as ion implantation and low-temperature molecular beam epitaxy, are used. Minimized post-doping thermal process is also necessary to reduce the diffusion. Even so, it is still a question if the introduced dopants are randomly distributed in the substitutional lattice positions. Therefore, proper atomic-scale characterization is also needed to verify the dopant distribution and chemical states. This symposium will be highly interdisciplinary, attracting participants from semiconductor, nanoelectronics, optoelectronics, plasmonics, superconductor and magnetism communities. According to information collected by four proposers, there are >20 groups in Europe, >10 groups in the US, >15 groups in China, >20 groups in Japan and Korea, >10 groups in India and other Asia area, >10 groups in Australia and the rest of the world. There has not been any similar symposium in the last years and it would fit to “Electronics, Magnetics and Photonics”.

Hot topics to be covered by the symposium:

• Optoelectronic devices based on hyperdoped Si, Ge, III-V and GeSn including photodetectors at infrared wavelength
• Hyperdoped semiconductors (Si, Ge and III-V) for plasmonics: tunable plasmonic frequency by doping concentration, plasmonic structural design
• Hyperdoped semiconductors (Si, Ge, SiGe and GeSn) for future field-effect transistors
• Highly mismatched alloys, such as GeSn, SiGeSn, GaAsN, GaPN …
• Ferromagnetic semiconductors, including transition metal doped III-V and IV semiconductors and their structural characterization
• Diamond, Si, Ge and SiC based superconductors: Boron doping, superconducting properties, applications for quantum technology
• Manufacturing hyperdoped and mismatched materials – Out of the equilibrium techniques, including ion implantation, low-temperature molecular beam epitaxy, lowtemperature chemical vapor deposition, pulsed laser melting and flash lamp annealing
• Advanced characterization technologies for impurities and defects at atomic scale: including Atom probe tomography (APT), High resolution transmission electron microscopy, Rutherford backscattering/channeling, Emission channeling, X-ray spectroscopies
• First-principle calculation regarding the impurity and defect configuration
• Challenges for doping emerging materials, such as 2D semiconductors, ultra-wide bandgap semiconductors and topological insulators
• New concepts for doping, such as polarization-induced hole doping in widebandgap semiconductors

List of invited speakers:

• Qing-Tai Zhao, Forschungszentrum Jülich GmbH, Semiconductor Nanoelectronics, Germany, Topic, Ge and GeSn based nanowire transistor.
• Patrick J. Strohbeen, Center for Quantum Information Physics, Department of Physics, New York University, New York, NY 10003 USA, Topic: Non-equilibrium MBE growth of ultra-doped group IV superconductors for quantum information.
• Sören Schäfer, Hochschule RheinMain University of Applied Sciences, AG Photonik, Germany, Topic: Sulfur-hyperdoped Si by femtosecond laser processing.
• Yaping Dan, University of Michigan–Shanghai Jiao Tong University Joint Institute Shanghai Jiao Tong University Shanghai, China, Topic: Single atom lithography by ion implantation and pulsed laser annealing.
• Eric García Hemme, Thin Films and Microelectronics Group, Universidad Complutense de Madrid (UCM), Plaza de Ciencias 1, Madrid 28040, Spain, Topic: Hyperdoped Si and Ge photodetectors.
• Magdalena Birowska, Faculty of Physics University of Warsaw, Poland, Topic: optoelectronic properties of van der Waals crystals from first principles.
• Oskar Maciej Liedke, Helmholtz-Zentrum Dresden-Rossendorf, Dresde, Germany, Topic: Defects in hyperdoped semiconductors visualised by positron annihilation lifetime spectroscopy.
• Raul Gago, Instituto de Ciencia de Materiales de Madrid (CSIC), Cantoblanco, 28049 Madrid, Spain, Topic: Bonding structure of doped metal oxides by means of X-ray absorption.
• Antoine Moreau, Université Clermont Auvergne, CNRS, Sigma Clermont, Institut Pascal, 63000, Clermont-Ferrand, France, Topic: Ultra-doped semiconductors for surface plasmons.
• Michele Amato, Laboratoire de Physique des Solides, Université Paris-Saclay, Orsay, France. Topic: Physical properties of Silicon-Germanium nanostructures: Theory and simulations.
• Steven Shofield, University College London (UK) – Topic; Characterisation of delta-doped Si by soft XR ARPES.
• Hung-Hsiang Cheng, Center for Condensed Matter Sciences, National Taiwan University, Taiwan. Topic: MBE growth of ultra-doped SiGeSn alloys.
• Che-Hao Liao, Department of Electronic Engineering, National Yunlin University of Science and Technology, Taiwan. Topic: Si-doped AlN on Sapphire for high speed devices.
• Hung-Wei Yen, Department of Materials Science & Engineering, National Taiwan University, National Taiwan University, Taiwan. Topic: Atom Probe Tomography, APT.