Mixed Ge-Si Dimer Growth at the Ge/Si(001)-(2×1) Surface

Comment on “Germanium dots with highly uniform size distribution grown on Si(100) substrate by molecular beam epitaxy” [Appl. Phys. Lett. 71, 3543 (1997)]

“…6,7 Therefore, on the basis of previous literature and our present results, the attribution of the PL lines at 0.767 and 0.789 eV to confined states in the very uniform Ge dots, proposed by Wang et al, 1 can be ruled out. Instead, we suggest that the PL emissions under consideration could be related to Ge/Si intermixing, which occurs intrinsically at the Si interface, 8,9 as proposed by Casalboni et al 4 Such an intermixing process is consistent with the observation of the SiGe wetting layer reported by Wang et al 1 and with the growth conditions of all the samples reported above. We think, however, that further, specifically addressed investigations are required to definitely determine the origin of the narrow PL lines located at 0.767 and 0.789 eV.…”

Surfactant adsorption site and growth mechanism of Ge- on Ga-terminated Si(111)

“…The conclusion on interfacial intermixing is supported by recent studies using high-resolution photoemission spectroscopy that also show substantial Ge-Si intermixing for MBE and SME grown Ge films on Si͑001͒. 19 The incorporation of Si into the Ga-Ge surface bilayer or intermixing of Ge and Si in bilayers below the interface have not been accounted for in the calculation. Nevertheless, we regard these processes to be additionally possible.…”

Evolution of the strain relaxation in a Ge layer on Si(001) by reconstruction and intermixing

“…In several previous experiments indications for a Si/Ge intermixing in the 2D layer were obtained, but it was difficult to quantify the amount of intermixing. 13,14 For the total-energy calculations, all deposited Ge atoms are placed in the top layers. When a certain amount of intermixing is considered at a coverage of 2 Ml, the periodicity of the (2ϫN) reconstruction increases.…”