Critical conditions for SiGe island formation during Ge deposition on Si(100) at high temperatures

详细信息    查看全文

• 作者：A.A. Shklyaev^a ; ^b ; ^{shklyaev@isp.nsc.ru" class="auth_mail" title="E-mail the corresponding author} ; A.E. Budazhapova^c
• 关键词：Ge MBE on Si(100) ; High-temperature growth ; Self-organization ; Strain relaxation ; Dynamic equilibrium
• 刊名：Materials Science in Semiconductor Processing
• 出版年：2017
• 出版时间：January 2017
• 年：2017
• 卷：57
• 期：Complete
• 页码：18-23
• 全文大小：1018 K

文摘

The strain relaxation during the Ge growth on Si(100) occurs vikia surface diffusion and Si-Ge intermixing at temperatures below 800 °C. The Ge diffusion into the Si substrate is an additional process at higher temperatures. We found that, if its rate is higher than the Ge deposition rate, the island formation is not realized. We determined the critical Ge deposition rate as a function of the temperature in the range of 840–960 °C, at which the dynamic equilibrium between the growth of islands and their decay through the diffusion takes place. The islands grown in the conditions close to the dynamic equilibrium are ordered with a distance between them of about 1 µm and they form a smoothed surface morphology. These are indicative of the surface layer strain uniformity. The islands have a SiGe composition which, in the direction parallel to the sample surface, is more uniform in comparison with the islands grown at lower temperatures. The results show that the use of high temperatures essentially improves the conditions for the heterostructure self-organization.