title: Low Temperature Deposition of High-k/Metal Gate Stacks on High-Sn Content (Si)GeSn-Alloys.
abstract: (Si)GeSn is an emerging group IV alloy system offering new exciting properties, with great potential for low power electronics due to the fundamental direct band gap and prospects as high mobility material. In this Article, we present a systematic study of HfO2/TaN high-k/metal gate stacks on (Si)GeSn ternary alloys and low temperature processes for large scale integration of Sn based alloys. Our investigations indicate that SiGeSn ternaries show enhanced thermal stability compared to GeSn binaries, allowing the use of the existing Si technology. Despite the multielemental interface and large Sn content of up to 14 atom %, the HfO2/(Si)GeSn capacitors show small frequency dispersion and stretch-out. The formed TaN/HfO2/(Si)GeSn capacitors present a low leakage current of 2 × 10(-8) A/cm(2) at -1 V and a high breakdown field of ∼8 MV/cm. For large Sn content SiGeSn/GeSn direct band gap heterostructures, process temperatures below 350 °C are required for integration. We developed an atomic vapor deposition process for TaN metal gate on HfO2 high-k dielectric and validated it by resistivity as well as temperature and frequency dependent capacitance-voltage measurements of capacitors on SiGeSn and GeSn. The densities of interface traps are deduced to be in the low 10(12) cm(-2) eV(-1) range and do not depend on the Sn-concentration. The new processes developed here are compatible with (Si)GeSn integration in large scale applications.
authors.affiliation: Peter Gruenberg Institute 9 (PGI 9) and JARA-FIT, Forschungszentrum Juelich GmbH, 52425 Juelich, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Schulte-Braucks
authors.affiliation: Peter Gruenberg Institute 9 (PGI 9) and JARA-FIT, Forschungszentrum Juelich GmbH, 52425 Juelich, Germany.
authors.forename: N
authors.initials: N
authors.lastname: von den Driesch
authors.affiliation: Peter Gruenberg Institute 9 (PGI 9) and JARA-FIT, Forschungszentrum Juelich GmbH, 52425 Juelich, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Glass
authors.affiliation: Peter Gruenberg Institute 9 (PGI 9) and JARA-FIT, Forschungszentrum Juelich GmbH, 52425 Juelich, Germany.
authors.forename: A T
authors.initials: AT
authors.lastname: Tiedemann
authors.affiliation: Zentralinstitut für Engineering, Elektronik und Analytik (ZEA-3), Forschungszentrum Juelich GmbH, 52425 Juelich, Germany.
authors.forename: U
authors.initials: U
authors.lastname: Breuer
authors.affiliation: Zentralinstitut für Engineering, Elektronik und Analytik (ZEA-3), Forschungszentrum Juelich GmbH, 52425 Juelich, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Besmehn
authors.affiliation: Univ. Grenoble Alpes, 38000 Grenoble, France and CEA, LETI, Minatec Campus, 38054 Grenoble, France.
authors.forename: J-M
authors.initials: JM
authors.lastname: Hartmann
authors.affiliation: Institute of Microwaves and Photonics, School of Electronic and Electrical Engineering, University of Leeds , Leeds LS2 9JT, United Kingdom.
authors.forename: Z
authors.initials: Z
authors.lastname: Ikonic
authors.affiliation: Peter Gruenberg Institute 9 (PGI 9) and JARA-FIT, Forschungszentrum Juelich GmbH, 52425 Juelich, Germany.
authors.forename: Q T
authors.initials: QT
authors.lastname: Zhao
authors.affiliation: Peter Gruenberg Institute 9 (PGI 9) and JARA-FIT, Forschungszentrum Juelich GmbH, 52425 Juelich, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Mantl
authors.affiliation: Peter Gruenberg Institute 9 (PGI 9) and JARA-FIT, Forschungszentrum Juelich GmbH, 52425 Juelich, Germany.
authors.forename: D
authors.initials: D
authors.lastname: Buca
keywords: GeSn; atomic vapor deposition; high-k/metal gate; high-mobility; low energy direct band gap