Influence of surface roughness and interfacial layer on the infrared spectra of V-CVD grown 3C-SiC/Si (100) epilayers
Journal
Semiconductor Science and Technology
Journal Volume
27
Journal Issue
11
Date Issued
2012
Author(s)
Abstract
We have reported room temperature infrared reflectance and transmission measurements at near normal incidence in the frequency range of 200–6500 cm−1 to characterize 3C-SiC epitaxial layers grown on (1 0 0) Si by CVD in a vertical reactor configuration by using different Si/C ratios and growth time ranging from 2 min to 4 h. The effects of surface roughness and 'conducting interfacial' transition layer are meticulously included in the effective medium theory for simulating the infrared spectra to explicate observed damping of interference fringe contrasts with increasing frequencies. In a few epitaxially grown samples we have adopted Bruggeman's two-component model to elucidate atypical divots seen within the reststrahlen band by assuming the coexistence of crystalline and intergranular grains forming heterogeneous 3C-SiC. The estimated values of surface roughness and conducting transition layer are correlated very well with the existing data from optical interference and scanning probe microscopy.
Type
journal article