Ge incorporation inside 4H-SiC during Homoepitaxial growth by chemical vapor deposition

摘要

In this work, we report on the addition of GeH4 gas during homoepitaxialgrowth of 4H-SiC by chemical vapour deposition. Ge introduction does not affectdramatically the surface morphology and defect density though it is accompaniedwith Ge droplets accumulation at the surface. The Ge incorporation level insidethe 4H-SiC matrix, ranging from few 1017 to few 1018 at.cm-3, was found to bemainly affected by the growth temperature and GeH4 flux. Other growthparameters like C/Si ratio, polarity, or off-orientation did not show anysignificant influence. On the other hand, adding GeH4 led to the increase ofthe intentional n type doping level by a factor of 2 to 5 depending on the C/Siratio in the gas phase.