A Comparison Between the Calculated and Experimental Effects of Enhanced Precursor Translational Kinetic Energy on SiC Growth on Si(100) and Si(L11) from Hexamethyldisilane

Abstract

Silicon Carbide thin films were grown on Si(100) and (111) substrates at 1050EC using a pulsed supersonic beam of hexamethyldisilane (HMDS) in hydrogen. X-ray diffraction analysis shows that these films contain only the 3C cubic polytype, determined mainly by the SiC(111) diffraction peak at 22 = 35.6E, the SiC(200) peak at 22 = 41.4E and the SiC(220) peak at 22 = 60.OE.

The angle of incidence of the HMDS/hydrogen beam could be varied through an angle of 0 to 90E without displacing the specimen from the focal point of the beam. On the Si(100) surface, the film growth texture was monitored by measuring the ratio of the SiC(111) to (200) diffraction peak intensity for beam incidence angles of 0, 30, 45 and 60E. On Si(111). The SiC(111)/(220) ratio was monitored. An 8-fold increase in the incident translational kinetic energy of the precursor molecules can be achieved at the highest glancing angle. In general, the effects of enhanced translational kinetic energy on SiC film growth were insignificant, in agreement with calculations of the sticking probability for SiC homoepitaxial growth with seeded beams on SiC [1]. Further examination of the films with SEM and AFM revealed the growth of epitaxial islands at low coverages, and the process of island coalescence.