Multiple layer local oxidation for fabricating semiconductor nanostructures

Abstract

Coupled semiconductor nanostructures with a high degree of tunability are fabricated using local oxidation with a scanning force microscope. Direct oxidation of the GaAs surface of a Ga[Al]As heterostructure containing a shallow two-dimensional electron gas is combined with the local oxidation of a thin titanium film evaporated on top. A four-terminal quantum dot and a double quantum dot system with integrated charge readout are realized. The structures are tunable via in-plane gates formed by isolated regions in the electron gas and by mutually isolated regions of the Ti film acting as top gates. Coulomb blockade experiments demonstrate the high quality of this fabrication process.

3 pages, 3 figures

References in corpus (2)

• In-plane gate single-electron transistor in Ga[Al]As fabricated by scanning probe lithography
• Combined atomic force microscope and electron-beam lithography used for the fabrication of variable-coupling quantum dots

Cited by in corpus (6)

• Phase coherence in the inelastic cotunneling regime
• Fano effect in a ring-dot system with tunable coupling
• Coherent probing of excited quantum dot states in an interferometer
• Statistical electron excitation in a double quantum dot induced by two independent quantum point contacts
• Measurement of the Tip-Induced Potential in Scanning Gate Experiments
• In Situ Treatment of a Scanning Gate Microscopy Tip