Kinetics of surface reactions in very lowhyphen;pressure chemical vapor deposition of Si from SiH4

摘要

A steadyhyphen;state kinetic model for the chemical vapor deposition (CVD) growth of Si films from SiH4on Si(100) is presented. The only adsorbing species is SiH4(absence of homogeneous SiH4dissociation is presumed). Model predictions of surface hydrogen coverage and Si film growth rate as a function of growth temperature (thinsp;Tthinsp;) are compared with literature values for these quantities. The rate ofeachreaction step is calculated at selectedT. Adsorption of SiH4and decomposition of SiH3control the growth rate in the highTlimit. In the lowTlimit, SiH4adsorption is slowest but is not a simple rate determining step. The SiH4adsorption rate is controlled by the rate of H2desorption from two surface SiH species, producing dangling bonds.