Structural characterization of thin 3C-SiC films annealed by flash lamp process

The formation of 3C-SiC epitaxially grown on Si wafers is still a considerable problem. Due to the 20% misfit between Si and 3C-SiC the defect density in the film is very high. the partial melting and subsequent recrystallization of the film by the flash lamp process can improve the quality of the thin 3C-SiC films. In this paper the microstructure of the annealed and partially recrystallized 35 nm thick films is studied by transmission electron microscopy. The films were grown by APCVD using Silane and Propane. The flash lamp annealing system consists of Xe lamps powered by discharging capacitors producing pulses of 20 ms. After irradiation almost free of defects 3C-SiC trapezoidal protrusions (TPs) are formed at the lower part of the film. In the uppermost part of the film the defect density was also reduced. The good quality of the TPs is shown by high resolution cross-section TEM observations. The good quality of the films was also confirmed by Plane View TEM observations of the moiré patterns in the as grown and annealed films. Moiré patterns are formed when the electron beam penetrates both the Si and the SiC lattices and are very sensitive to any lattice distortion or defects.