Negative differential resistance in isolated GaN nanowires with focused electron beam deposited platinum contacts

Author

Dhabal, A. ; Chander, D.S. ; Ramkumar, J. ; Dhamodaran, S.

Author_Institution

Dept. of Phys., Indian Inst. of Technol. Kanpur, Kanpur, India

Volume

6

Issue

4

fYear

2011

fDate

4/1/2011 12:00:00 AM

Firstpage

280

Lastpage

283

Abstract

Straight and zig-zag isolated GaN nanowires were investigated for their electrical properties using focused ion/electron beam (FIB/FEB) deposited platinum contacts. The straight and smooth nanowire with FIB contacts was non-ohmic and relatively high leakage current was observed under reverse bias. The straight and smooth nanowire with FEB contact shows ohmic behaviour whereas the zig-zag nanowire shows non-ohmic with negative differential resistance (NDR). The peak-to-valley current ratio was about 4.5 at room temperature under forward bias. The NDR observed in the zig-zag nanowires has been explained based on inelastic tunnelling through electrically active acceptor-like defect states present within the bandgap.

Keywords

III-V semiconductors; contact resistance; defect states; energy gap; gallium compounds; leakage currents; nanowires; negative resistance; ohmic contacts; platinum; semiconductor-metal boundaries; tunnelling; wide band gap semiconductors; GaN-Pt; bandgap; electrical properties; electrically active acceptor-like defect states; focused electron beam deposition; focused ion beam deposition; forward bias; inelastic tunnelling; leakage current; negative differential resistance; nonohmic contacts; ohmic contact; peak-to-valley current ratio; reverse bias; straight isolated nanowires; temperature 293 K to 298 K; zigzag isolated nanowires;

fLanguage

English

Journal_Title

Micro & Nano Letters, IET

Publisher

iet

ISSN

1750-0443

Type

jour

DOI

10.1049/mnl.2011.0043

Filename

5771643