Deposition, evaluation and control of 4H and 6H SiC epitaxial layers for device applications

We report an experimental investigation of the deposition, optical characterization and electrical properties of 6H and 4H-SiC epitaxial layers grown by atmospheric pressure chemical vapor deposition in a home made ‘cold wall’ reactor. From a growth kinetic study performed using our deposition conditions (1 atm, 1700 K) we show that our results can be very well explained using a stagnant layer model. We also underline that the decrease of the growth efficiency for high molar fractions of silane comes from the occurrence of a gaseous phase nucleation. The electronic properties of the resulting layers have been studied by Hall effect measurements. The values of electrons mobility (900 cm2 Vs−1 for a low doped layer) compare well with those of other groups. Finally, Schottky diodes have been processed with good forward characteristics.