Optimizing ToF-SIMS Depth Profiles of Semiconductor Heterostructures

arXiv (Cornell University)

Abstract

The continuous technological development of electronic devices and the introduction of new materials leads to ever greater demands on the fabrication of semiconductor heterostructures and their characterization. This work focuses on optimizing Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) depth profiles of semiconductor heterostructures aiming at a minimization of measurement-induced profile broadening. As model system, a state-of-the-art Molecular Beam Epitaxy (MBE) grown multilayer homostructure consisting of $^{\textit{nat}}$Si/$^{28}$Si bilayers with only 2 nm in thickness is investigated while varying the most relevant sputter parameters. Atomic concentration-depth profiles are determined and an error function based description model is used to quantify layer thicknesses as well as profile broadening. The optimization process leads to an excellent resolution of the multilayer homostructure. The results of this optimization guide to a ToF-SIMS analysis of another MBE grown heterostructure consisting of a strained and highly purified $^{28}$Si layer sandwiched between two Si$_{0.7}$Ge$_{0.3}$ layers. The sandwiched $^{28}$Si layer represents a quantum well that has proven to be an excellent host for the implementation of electron-spin qubits.

Authors 8

1. Jan Tröger
2. Reinhard Kersting
   Affiliation as printed

   Tascon GmbH , 48149 Münster , Germany

3. Birgit Hagenhoff
   Affiliation as printed

   Tascon GmbH , 48149 Münster , Germany

4. Dominique Bougeard

   University of Regensburg

   Affiliation as printed

   Institut für Experimentelle und Angewandte Physik , Universität Regensburg , 93040 Regensburg , Germany

5. Nikolay V. Abrosimov

   Leibniz Institute for Crystal Growth

   Affiliation as printed

   Leibniz-Institut für Kristallzüchtung (IKZ) , 12489 Berlin , Germany

6. Jan Klos Aachen JARA-FIT Institute for Quantum Information

   Forschungszentrum Jülich · Jülich Aachen Research Alliance · RWTH Aachen University

   Affiliation as printed

   JARA-FIT Institute for Quantum Information , Forschungszentrum Jülich GmbH and RWTH Aachen University , 52056 Aachen , Germany

7. Lars R. Schreiber Aachen JARA-FIT Institute for Quantum Information

   Forschungszentrum Jülich · Jülich Aachen Research Alliance · RWTH Aachen University

   Affiliation as printed

   ARQUE Systems GmbH , 52074 Aachen , Germany

   JARA-FIT Institute for Quantum Information , Forschungszentrum Jülich GmbH and RWTH Aachen University , 52056 Aachen , Germany

8. Hartmut A. Bracht

   University of Münster

   Affiliation as printed

   Institute of Materials Physics , University of Münster , 48149 Münster , Germany