Computer modeling of morphological evolution and RHEED intensity oscillations of thin-film growth by laser molecular beam epitaxy

SURFACE SCIENCE

卷:380

Article

关键词: computer simulations;    growth;    reflection high-energy electron diffraction (RHEED);    super conducting film;   

DOI  :  10.1016/S0039-6028(97)00034-4

来源: Elsevier

【 摘 要 】

The morphological evolution of the unit cell by unit cell layer growth of thin films by laser molecular beam epitaxy (laser MBE) is simulated by the Monte Carlo (MC) method. As a more realistic simulation, the effect of the surface terrace on reflection high-energy electron diffraction (RHEED) intensity oscillations is considered in our model. The calculation shows that the surface terrace effect has an obvious influence on the intensity oscillation shapes. Moreover, we consider the growth units impinging on the surface batch by batch rather than one by one. It is found that the surface morphologies are different, with different numbers of units impinging by a laser pulse on the surface. Furthermore, the surface roughness increases with a decrease in substrate temperature and with an increase in the unit impinging rate (which is determined by the energy of each laser pulse). The validity of the growth model is demonstrated by comparing our MC-simulated RHEED intensity oscillations with those observed in laser MBE experiments. (C) 1997 Elsevier Science B.V.

【 授权许可】

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