Highly ordered Ga nanodroplets on a GaAs surface formed by a focused ion beam.

Ion-Beam-Directed Self-Ordering of Ga Nanodroplets on GaAs Surfaces

Ordered nanodroplet arrays and aligned nanodroplet chains are fabricated using ion-beam-directed self-organization. The morphological evolution of nanodroplets formed on GaAs (100) substrates under ion beam bombardment is characterized by scanning electron microscopy and atomic force microscopy. Ordered Ga nanodroplets are self-assembled under ion beam bombardment at off-normal incidence angles...

Photoelectrochemical passivation of GaAs surfaces

A wet. chemical techniq~e is ~escribed for passivating air-exposed GaAs surfaces. The passivating ~ayer IS elemental arsemc WhICh forms as a result of illuminating an n-type GaAs wafer immersed ~n a ~i~ture of Hel acid and d~ionized 18 Mil water with light from a mercury vapor lamp at mtenSltles of 0.01-0.05 yY-cm. Studies using XPS, LEBD, and UPS show that the passivated surfaces have the foll...

Lithography-free positioned GaAs nanowire growth with focused ion beam implantation of Ga

Lateral patterning of multilayer InAs/GaAs(001) quantum dot structures by in vacuo focused ion beam.

We report on the effects of patterning and layering on multilayer InAs/GaAs(001) quantum dot structures laterally ordered using an in vacuo focused ion beam. The patterned hole size and lateral pattern spacing affected the quantum dot size and the fidelity of the quantum dots with respect to the lateral patterns. 100% pattern fidelity was retained after six layers of dots for a 9.0 ms focused i...

High temperature ballistic transport observed in AIGaAs/lnGaAs/GaAs small four-terminal structures

Four-terminal structures are fabricated by focused-ion-beam (FIB) scanning on an AlGaAs/ InGaAs/GaAs modulation doped structure. The large carrier density of this system results in small depletion spreading and a 260-nm-square four-terminal structure is successfully formed. The bend resistance of this structure indicates that ballistic coupling between two facing terminals remains up to room te...