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The investigation of epitaxial molecular beam epitaxy growth of nanometric Germanium layers on silicon (001) 2 by 1, in situ, by X-ray silicon 2p photoelectron diffraction and Auger Ge LMM electron diffraction which consists primarily of preferential scattering of electrons in the direction of interatomic axes. The crystalline material quality and epitaxial perfection are affected by the residual pressure below a certain range, a decrease in the substrate temperature to room temperature, the deposition rate and the Ge overlayer thickness.

The Si capping of small Ge dots nucleated on a C-precovered Si (001) surface has been investigated by means of reflection high-energy electron diffraction and atomic force microscopy. The growth at 500° C of three Ge monolayers on the C-induced c (4× 4) reconstruction leads to the nucleation of isolated dots, without any wetting layer. Up to a nominal thickness of 5 nm, the surface evolution during the Si cap layer deposition reveals island preservation. Contrary to the Si capping situation of Ge islands on bare Si surfaces (without C seeding), where a surface smoothing is observed after few monolayers, the modified C-induced surface strain promotes a final Si adatom adsorption on the top of the Ge islands. A rough morphology is therefore maintained during the cap layer growth by this selective Si coverage. The general surface smoothing and the in-plane lattice parameter recovery toward Si bulk values are also strongly delayed. [ABSTRACT FROM AUTHOR]

Si surfaces manipulated by a carbon (C) pre-deposition have been used to modify the growth morphology of Ge islands. In situ reflection high-energy electron diffraction and x-ray photoelectron diffraction and ex situ atomic force microscopy studies have been conducted for constant C seeding and varying growth temperatures and Ge coverages, with the aim of deepening the understanding of the relevant Ge quantum dot formation. With temperatures ranging from 400 to 600 °C, well structured Ge islands grow in a Volmer–Weber mode as soon as 0.4 ML of C and 1 ML of Ge are deposited. Strongly modified behaviors are nevertheless observed by changing the Ge growth temperature from 500 to 600 °C. By increasing the Ge coverage from 1 to 6 ML at 500 °C, the island height increases at constant density, whereas, at 600 °C, a strong reduction of the density is observed, with a three-dimensional-two-dimensional transition probably due to a partial Ge intermixing in the Si matrix. These different nucleation schemes are connected with varying evolutions of the initial C-related c(4×4) reconstruction. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The growth of Ge monolayer on C-induced c (4*4) reconstruction leading to nucleation of isolated dots without any wetting layer is described. With the use of atomic force microscope (AFM) and reflection high energy electron diffraction (RHEED) the Si overgrowth processes on C-induced Ge dots is investigated.

Investigates the epitaxial molecular beam epitaxy growth of nanometric germanium layers on silicon (001) 2 X 1. Characterization methods used to control the growth of available germanium molecular beam epitaxy deposits; Details on the experiment; Results of the study.