Atomically Controlled Processing in Silicon-Based CVD Epitaxial Growth

作者：Murota Junichi^*; Sakuraba Masao; Tillack Bernd

来源：Journal of Nanoscience and Nanotechnology, 2011, 11(9): 8348-8353.

DOI：10.1166/jnn.2011.5052

• Atomically Controlled Processing
• Atomic Layer Doping
• Chemical Vapor Deposition
• Group IV Semiconductor
• Si
• Ge
• N
• P
• C

One of the main requirements for Si-based ultrasmall device is atomic-order control of process technology. Here, we show the concept of atomically controlled processing for group IV semiconductors based on atomic-order surface reaction control in Si-based CVD epitaxial growth. Self-limiting formation of 1-3 atomic layers of group IV or related atoms after thermal adsorption and reaction of hydride gases on Si(1-x)Ge(x),(100) (x = 0-1) surface are generalized based on the Langmuir-type model. Moreover, Si-based epitaxial growth on N, P or C atomic layer formed on Si(1-x)Ge(x)(100) surface is achieved at temperatures below 500 degrees C. N atoms of about 4 x 10(14) cm(-2) are buried in the Si epitaxial layer within about 1 nm thick region. In the Si(0.6)Ge(0.5) epitaxial layer, N atoms of about 6 x 10(14) cm(-2) are confined within about 1.5 nm thick region. The confined N atoms in Si(1-x)Ge(x) preferentially form Si-N bonds. For unstrained Si cap layer grown on top of the P atomic layer formed on Si(1-x)Ge(x)(100) with P atomic amount of below about 4 x 10(14) cm(-2) using Si(2)H(6) instead of SiH(4), the incorporated P atoms are almost confined within 1 nm around the heterointerface. It is found that tensile-strain in the Si cap layer growth enhances P surface segregation and reduces the incorporated P atomic amount around the heterointerface. Heavy C atomic-layer doping suppresses strain relaxation as well as intermixing between Si and Ge at the nm-order thick Si(1-x)Ge(x)/Si heterointerface. These results open the way to atomically controlled technology for ULSIs.

• 出版日期2011-9