Master Thesis

FZJ-2021-01138

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png MBE growth and characterization of InAs based core-shell nanowire arrays

Wu, D. (Corresponding author)FZJ* ; Lepsa, M. I. (Thesis advisor)FZJ*

2021
Forschungszentrum Jülich Jülich

Please use a persistent id in citations: http://hdl.handle.net/2128/27273

Abstract: Among III-V compound semiconductor nanowires, InAs nanowires have high electronmobility which make them suitable for low power field-effect transistors. The Fermi levelpinning above its conduction band minimum results in easy fabrication of ohmic contacts.However, due to the large surface-to-volume ratio of nanowires, the surface states canhave impact on the electrical property of InAs nanowires and therefore the influence ofpassivation is interesting to be investigated. The first part of this report focuses on themolecular beam epitaxy (MBE) growth of InAs nanowire arrays on prepatterned Si(111)substrates. Using a new in-situ Ga droplet assisted substrate preparation, a highreproducibility of the growth results with high nanowire yield is achieved. Afterwards, thein-situ passivation of InAs nanowire by Al2O3 shell using atomic layer deposition (ALD) issuccessfully realized. In addition, the MBE growth of InAs-Al0.6Ga0.4Sb core-shellnanowire is studied and the growth rate of AlGaSb shell is estimated. The second part isrelated to the fabrication of InAs nanowire-array based device using HSQ as planarizationlayer. After the fabrication, each nanowire array as a whole is connected by top andbottom electrodes vertically. The third part contains the DC electrical characterization ofthe InAs nanowire-array based devices at room temperature. The comparison betweenthe resistivity of unpassivated and Al2O3 passivated InAs nanowire arrays shows that thelatter is lower demonstrating the benefit demonstrating the benefit of passivation.

Keyword(s): Materials Science (2nd)

Note: Masterarbeit, RWTH Aachen, 2020

---

Contributing Institute(s):

1. Halbleiter-Nanoelektronik (PGI-9)

Research Program(s):

1. 522 - Quantum Computing (POF4-522) (POF4-522)

Appears in the scientific report 2021

---

Database coverage:

---