The special features of adsorption and the kinetics of decomposition of monosilane molecules on the epitaxial surface of silicon |
| |
Authors: | L K Orlov S V Ivin and T N Smyslova |
| |
Abstract: | Analytic equations relating the rate of the incorporation of silicon atoms into a growing crystal to the characteristic frequency
of the pyrolysis of silane molecules on the surface of silicon were obtained over the temperature range corresponding to the
epitaxial growth of silicon films. As distinct from the earlier works, it was assumed that adsorbed silicon atoms and monosilane
molecules formed double bonds with the surface. The data of technological experiments for the most extensively used pyrolysis
models obtained thus far were used to determine the region of the characteristic frequencies of the decomposition of hydride
molecule radicals adsorbed on the surface of a silicon plate over the temperature range 450–700°C. The temperature dependence
of the frequency of monosilane molecule decomposition was shown to be to a great extent determined by the form of the temperature
dependence of the $
\tilde v_{SiH_2 }^0
$
\tilde v_{SiH_2 }^0
preexponential factor. It was also found that the characteristic frequency of the decomposition of silane molecules was sensitive
to the stage of pyrolysis at which hydrogen atoms released from silane molecules were captured by the surface. Decomposition
occurred at the highest rate if hydrogen molecules were adsorbed at the stage of the adsorption of monosilane. The lowest
rate of decomposition was observed if hydrogen molecules were adsorbed at the stage of the decomposition of radicals already
captured by the surface. The temperature dependence of the coefficient of adsorption of monosilane molecules was characterized
by a negative activation energy of the process for almost all the most important system models over the temperature range
of growth. At elevated growth temperatures, the adsorption of monosilane molecules by the surface of silicon proceeded via
an intermediate state characterized by the difference of desorption and chemisorption energies on the order of 0.28 eV. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |