Fabrication of quantum nanostructures by selective area MOVPE and their device application

摘要

We report on the formation of quantum nanostructures and their arrays by selective area metalorganic vapor phase epitaxy (SA-MOVPE) on masked substrates and their application to quantum devices and circuits. With appropriately designed masked substrates, various kinds of nanostructures, such as quantum dot-quantum wire coupled structure arrays are realized. When SA-MOVPE is carried out on (111)B substrates, triangular lattice arrays of hexagonal air holes or pillars consisting of {110} facet sidewalls can be formed, which can be used for photonic crystals. For device application of such nanostructures, we fabricate single electron transistors in combination with lithographically defined dual gated structures, in which clear Coulomb oscillations and Coulomb diamonds are observed. Applications to logic circuits using single electron transistors are also described.