Design and Characterization of a Sharp GaAs/Zn(Mn)Se Heterovalent Interface: A Sub-Nanometer Scale View

• Published in: Nanomaterials (Basel, Switzerland) Vol. 10; no. 7; p. 1315
• Main Authors: Grossi, Davide F, Koelling, Sebastian, Yunin, Pavel A, Koenraad, Paul M, Klimko, Grigory V, Sorokin, Sergey V, Drozdov, Mikhail N, Ivanov, Sergey V, Toropov, Alexey A, Silov, Andrei Y
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 04-07-2020; MDPI
• Subjects: Defects; diffusion; diluted magnetic semiconductors; dopants; Growth conditions; Impurities; Magnetic semiconductors; Mass spectroscopy; Mn impurities; Optical properties; segregation; Selenium; Semiconductors; Zinc; ZnSe/GaAs interface; dopants; Mn impurities; diluted magnetic semiconductors; diffusion; segregation; ZnSe/GaAs interface
• ISSN: 2079-4991; 2079-4991
• DOI: 10.3390/nano10071315

The distribution of magnetic impurities (Mn) across a GaAs/Zn(Mn)Se heterovalent interface is investigated combining three experimental techniques: Cross-Section Scanning Tunnel Microscopy (X-STM), Atom Probe Tomography (APT), and Secondary Ions Mass Spectroscopy (SIMS). This unique combination allowed us to probe the Mn distribution with excellent sensitivity and sub-nanometer resolution. Our results show that the diffusion of Mn impurities in GaAs is strongly suppressed; conversely, Mn atoms are subject to a substantial redistribution in the ZnSe layer, which is affected by the growth conditions and the presence of an annealing step. These results show that it is possible to fabricate a sharp interface between a magnetic semiconductor (Zn(Mn)Se) and high quality GaAs, with low dopant concentration and good optical properties.