title: The effect of nitrogen pressure during molecular beam epitaxy growth of InAsN quantum dots.
abstract: The influence of N flux during molecular beam epitaxy growth of InAsN quantum dots was studied. Growth of InAsN dots under high N flux was shown to give rise to an abnormal growth behaviour compared to InAs dots and InAsN dots with lower nitrogen content. Cubic In(x)Ga(1-x)N (x = 0.21 ± 0.01) crystallites were found in samples grown with an excessive N flux. The crystallites are likely to form ∼0.6 monolayers (MLs) after the quantum dots have nucleated, when the quantum dot changes growth mode. In addition, it is shown that a bimodal size distribution of InAsN quantum dots was generated in the wetting layer during the dot growth, as opposed to nucleation at N-induced dislocations at the substrate surface. The bimodal distribution may be explained by an increased energy barrier, in the presence of nitrogen, for atomic incorporation into the dots.
authors.affiliation: School of Electrical and Electronic Engineering, Nanyang Technological University, Nanyang Avenue, Singapore. Singapore-MIT Alliance, Nanyang Avenue, 639798, Singapore.
authors.forename: J F
authors.initials: JF
authors.lastname: Fälth
authors.forename: S F
authors.initials: SF
authors.lastname: Yoon
authors.forename: K H
authors.initials: KH
authors.lastname: Tan
authors.forename: E A
authors.initials: EA
authors.lastname: Fitzgerald