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arXiv · 1202.6224

Application of hydrogenation to low-temperature cleaning of the Si(001) surface in the processes of molecular-beam epitaxy: Investigation by STM, RHEED and HRTEM

L. V. Arapkina·L. A. Krylova·K. V. Chizh·V. A. Chapnin·O. V. Uvarov·V. A. Yuryev
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Abstract

Structural properties of the clean Si(001) surface obtained as a result of low-temperature (470--650C) pre-growth annealings of silicon wafers in a molecular-beam epitaxy chamber have been investigated. To decrease the cleaning temperature, a silicon surface was hydrogenated in the process of a preliminary chemical treatment in HF and NH_4F aqueous solutions. It has been shown that smooth surfaces composed by wide terraces separated by monoatomic steps can be obtained by dehydrogenation at the temperatures > 600C, whereas clean surfaces obtained at the temperatures < 600C are rough. It has been found that there exists a dependence of structural properties of clean surfaces on the temperature of hydrogen thermal desorption and the process of the preliminary chemical treatment. The frequency of detachment/attachment of Si dimers from/to the steps and effect of the Ehrlich-Schwoebel barrier on ad-dimer migration across steps have been found to be the most probable factors determining a degree of the resultant surface roughness.

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L. V. Arapkina, L. A. Krylova, K. V. Chizh, V. A. Chapnin, O. V. Uvarov, V. A. Yuryev. 2012-06-08. Application of hydrogenation to low-temperature cleaning of the Si(001) surface in the processes of molecular-beam epitaxy: Investigation by STM, RHEED and HRTEM. https://doi.org/10.1063/1.4732073

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