Te incorporation and activation as n-type dopant in self-catalyzed GaAs nanowires

Author(s):Show less -

Hakkarainen, Teemu ^[1] ; Piton, Marcelo Rizzo ^{[2, 1]} ; Fiordaliso, Elisabetta Maria ^[3] ; Leshchenko, Egor D. ^[4] ; Koelling, Sebastian ^[5] ; Bettini, Jefferson ^[6] ; Avanco Galeti, Helder Vinicius ^[7] ; Koivusalo, Eero ^[1] ; Gobato, Yara Galva ^{[2, 8]} ; Rodrigues, Ariano de Giovanni ^[2] ; Lupo, Donald ^[9] ; Koenraad, Paul M. ^[5] ; Leite, Edson Roberto ^[6] ; Dubrovskii, Vladimir G. ^[10] ; Guina, Mircea ^[1]

Affiliation

^[1] Tampere Univ, Optoelect Res Ctr, Phys Unit, Korkeakoulunkatu 3, Tampere 33720 - Finland

^[2] Univ Fed Sao Carlos, Phys Dept, BR-13565905 Sao Carlos, SP - Brazil

^[3] Tech Univ Denmark, Natl Ctr Nano Fabricat & Characterizat, Nanolab, DK-2800 Lyngby - Denmark

^[4] Lund Univ, Solid State Phys & NanoLund, Box 118, S-22100 Lund - Sweden

^[5] Eindhoven Univ Technol, Photon & Semicond Nanophys, Dept Appl Phys, NL-5600 MB Eindhoven - Netherlands

^[6] CNPEM, Brazilian Nanotechnol Natl Lab LNNano, R Giuseppe Maximo Scolfaro 10000, Campinas, SP - Brazil

^[7] Univ Fed Sao Carlos, Elect Engn Dept, BR-13565905 Sao Carlos, SP - Brazil

^[8] Radboud Univ Nijmegen, High Field Magnet Lab, NL-6525 ED Nijmegen - Netherlands

^[9] Tampere Univ, Lab Elect & Commun Engn, Korkeakoulunkatu 3, FI-33720 Tampere - Finland

^[10] ITMO Univ, Kronverkskiy Pr 49, St Petersburg 197101 - Russia

• Document type: Journal article
• Source: PHYSICAL REVIEW MATERIALS; v. 3, n. 8 AUG 5 2019.
• Web of Science Citations: 0

Abstract

Dopant atoms can be incorporated into nanowires either via the vapor-liquid-solid mechanism through the catalyst droplet or by the vapor-solid growth on the sidewalls. Si is a typical n-type dopant for GaAs, but in nanowires it often suffers from a strongly amphoteric nature in the vapor-liquid-solid process. This issue can be avoided by using Te, which is a promising but less common alternative for n-type doping of GaAs nanowires. Here, we present a detailed investigation of Te-doped self-catalyzed GaAs nanowires. We use several complementary experimental techniques, such as atom probe tomography, off-axis electron holography, micro-Raman spectroscopy, and single-nanowire transport characterization, to assess the Te concentration, the free-electron concentration, and the built-in potential in Te-doped GaAs nanowires. By combing the experimental results with a theoretical model, we show that Te atoms are mainly incorporated by the vapor-liquid-solid process through the Ga droplet, which leads to both axial and radial dopant gradients due to Te diffusion inside the nanowires and competition between axial elongation and radial growth of nanowires. Furthermore, by comparing the free-electron concentration from Raman spectroscopy and the Te-atom concentrations from atom probe tomography, we show that the activation of Te donor atoms is 100% at a doping level of 4 x 10(18) cm(-3), which is a significant result in terms of future device applications. (AU)

• FAPESP's process: 18/01808-5 - Optical and Transport Properties in High Magnetic Fields of Semiconductor Heterostructures and Devices based on Two Dimensional Materials
• Grantee: Yara Galvão Gobato
• Support Opportunities: Scholarships abroad - Research
• FAPESP's process: 14/50513-7 - Tailoring the transport and optical properties if III-Bi-V nanostructures for advanced photonic devices
• Grantee: Helder Vinícius Avanço Galeti
• Support Opportunities: Regular Research Grants
• FAPESP's process: 16/10668-7 - Optical and Transport Properties of two-dimensional semicondutors based on transition metal dichalcogenides
• Grantee: Yara Galvão Gobato
• Support Opportunities: Regular Research Grants