Epitaxy

Silicon carbide has the well-established position as a key material for high power, high temperature, and harsh environment devices.

This position is not threatened by the industrial developments of the “ultimate” wide band-gap semiconductor – diamond – which are just beginning. The fact remains that the substrates for the deposition of homoepitaxial SiC layers are extremely expensive as compared to other semiconductor materials, and available diameters are limited to 100mm. For that reason the heteroepitaxial growth of cubic polytype of SiC (3C-SiC) on silicon could be considered as an interesting alternative to homoepitaxial deposition of hexagonal polytypes (4H- and 6H-SiC).

The developments made in the field of 3C-SiC technology by NOVASiC enable the use of cubic silicon carbide for MEMS sensors for harsh environment or as stress-reducing templates for ZnO or as the substrate for III-nitrides epitaxy.

The 3C-SiC layers provided by NOVASiC are grown using a classical two stage process in an original Chemical Vapor Deposition (CVD) system, developed within the framework of the long term cooperation between NOVASiC and CRHEA–CNRS.

Various technical and scientific aspects of these 3C-SiC processes and products were described by NOVASiC and CRHEA-CNRS in several publications and presented at international conferences (see publications). The subjects that were studied range from the role of nucleation layer and the mechanism of its formation, to in-situ doping of the layers, and strain control within the deposited layer. The latter was intensively studied in order to avoid excessive wafer bending that could make further processing steps (polishing, photo-lithography, regrowth...) difficult or impossible.