Magnetoresistance fluctuations in InAs nanoscale open-dot structures produced using AFM oxidation process

摘要

InAs nanoscale open-dot structures with the feature size less than 100 nm were fabricated by using a newly developed AFM oxidation process. A greatly improved writing speed of 100 nm/s was obtained by using a Si tip together with higher ambient humidity of 60%. Open-dot structures with 100×100, 200×200, 300×300, μm{sup}2 were successfully fabricated in a 15-nm-thick lnAs surface inversion layer. The pronounced magneto-resistance fluctuations with a periodicity depending on the dot size were observed. The decrease in the oscillation period and the reduction in the fluctuation amplitude can be explained by the Aharonov-Bohm oscillations and the dephasing in the dot. The deduced phase-breaking time is about 1 ps in spite of the low mobility in the lnAs.