Correlation between Al grain size, grain boundary grooves and local variations in oxide barrier thickness of Al/AlOx/Al tunnel junctions by transmission electron microscopy
Journal article, 2016

A thickness variation of only one Ångström makes a significant difference in the current through a tunnel junction due to the exponential thickness dependence of the current. It is thus important to achieve a uniform thickness along the barrier to enhance, for example, the sensitivity and speed of single electron transistors based on the tunnel junctions. Here, we have observed that grooves at Al grain boundaries are associated with a local increase of tunnel barrier thickness. The uniformity of the barrier thickness along the tunnel junction thus increases with increasing Al grain size. We have studied the effect of oxidation time, partial oxygen pressure and also temperature during film growth on the grain size. The implications are that the uniformity improves with higher temperature during film growth.

Grain size

TEM

Tunnel junction

Author

Samira Mousavi Nik

Chalmers, Physics, Eva Olsson Group

Philip Krantz

Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics

Lunjie Zeng

Chalmers, Physics, Eva Olsson Group

Tine Greibe

Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics

Henrik Pettersson

Chalmers, Physics, Materials Microstructure

Stefan Gustafsson

Chalmers, Physics, Eva Olsson Group

Per Delsing

Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics

Eva Olsson

Chalmers, Physics, Eva Olsson Group

SpringerPlus

2193-1801 (ISSN)

Vol. 5 1 1067- 1067

Areas of Advance

Nanoscience and Nanotechnology

Subject Categories

Nano Technology

Condensed Matter Physics

DOI

10.1186/s40064-016-2418-8

More information

Latest update

10/29/2018