Papers by Author: Francisco M. Morales

Abstract: The influence of the growth conditions on the 3C-SiC layer quality in terms of crystallinity, morphology and residual strain was investigated. In dependence on the chosen growth conditions the stress state can be varied between inhomogeneous and homogeneous strain. For the reduction of the residual strain an alternative route for the improvement of the epitaxial growth of 3CSiC( 100) on Si(100) was developed. It consists in covering the silicon wafers with germanium prior to the carbonization step. The achieved improvement in the residual strain and crystalline quality of the grown 3C-SiC layers is comparable to SOI substrates. These beneficial effects were reached by using a Ge coverage in the range of 0.5 to 1 monolayer with respect to the silicon surface.

Abstract: Flash lamp annealing of multilayer stack of the type SiC/Silicon overlayer(SOL)/SiC reduces the defect densities in the 3C-SiC/Si heteroepitaxial structure. Ge and C additions to the SOL lead to a substantial increase of the mass transfer from the upper layer to the lower SiC layer. If the Ge content of the SOL and the flash lamp annealing conditions are properly chosen a homogeneous layer with a 3C-SiC thickness between 150 and 200 nm can be achieved corresponding to a growth rate between 7.5 and 10.0 +m/s. The thickening of the lower layer depends on the SOL composition. Ge and/or C incorporation into the SOL and therefore into the Si melt enhances the mass transport from the upper SiC layer to the lower one.