Formation of Nanostructures in a Heterojunction with a Deeply Located 2D Electron Gas via the Method of High-Voltage Anodic-Oxidation Lithography Using an Atomic-Force Microscope

摘要

A technique of high-voltage local anodic oxidation of the surfaces of Ga[Al] As-based heterostruc-tures with the use of an atomic-force microscope is described. The application of a pulsed voltage and use of semicontact operating regime of the atomic-force microscope allowed obtainment of a locally depleted 2D electron gas (2DEG) at an unusually large depth of 80 nm from the surface. This circumstance makes it possible to create 2DEG-based ballistic nanostructures characterized by a high mobility of carriers. The technique of preparing an open quantum dot in the 2DEG with a mobility of μ ≈ 3 × 10{sup}6 enr/(V s) at 4.2 K is described and the results of low-temperature test measurements of its conductivity are presented.