Optimization of surface pretreatment for single GaN nanowire devices

The correlation of residual contamination with void formation at the contact/SiO2 interface for single GaN nanowire (NW) devices was investigated. The morphology of the metal/SiO2 interface was studied by removing annealed Ni/Au films from the SiO2 surface with carbon tape, mounting the films for sc...

Ausführliche Beschreibung

Gespeichert in:
Bibliographische Detailangaben
Veröffentlicht in:Journal of Vacuum Science & Technology B: Microelectronics and Nanometer Structures 2012-11, Vol.30 (6)
Hauptverfasser: Herrero, Andrew M., Bertness, Kris A.
Format: Artikel
Sprache:eng
Online-Zugang:Volltext
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
Beschreibung
Zusammenfassung:The correlation of residual contamination with void formation at the contact/SiO2 interface for single GaN nanowire (NW) devices was investigated. The morphology of the metal/SiO2 interface was studied by removing annealed Ni/Au films from the SiO2 surface with carbon tape, mounting the films for scanning electron microscopy and imaging. Formation of voids at the metal/SiO2 interface, which can negatively affect device performance, was shown to occur during annealing of Ni/Au contacts to NWs on SiO2. It was discovered that residual contamination, both from the NW solution and from photolithographic processes on the NW-SiO2 surface prior to metal deposition, can cause significant increases in the number of voids observed at the metal/SiO2 interface. Various predeposition cleaning methods were investigated in order to minimize the amount of void formation associated with residual contamination. The degree of void formation at the metal/SiO2 interface is used to evaluate the effectiveness of each cleaning method. It was determined that the most effective cleaning method for removing residual contamination from the NW-SiO2 surface was an ultraviolet ozone treatment followed by a dilute HCl bath, immediately preceding contact deposition.
ISSN:2166-2746
1520-8567
2166-2754
DOI:10.1116/1.4754701