An atomic force microscopy and optical microscopy study of various shaped void formation and reduction in 3C-SiC films grown on Si using chemical vapor deposition

TL;DR

This study investigates the formation and reduction of various shaped voids in 3C-SiC films grown on silicon substrates using chemical vapor deposition, highlighting the influence of substrate orientation and growth conditions.

Contribution

It provides new insights into how substrate orientation, growth temperature, and time affect void shape, size, and density in 3C-SiC films, and demonstrates methods to reduce voids.

Findings

Void shapes depend on substrate orientation and growth conditions.

Void size and density can be significantly reduced with optimized growth techniques.

Void faceting occurs along {111} planes and other high-energy facets.

Abstract

The formation of various uncommon shaped voids along with regular triangular and square voids in the epitaxial 3C-SiC films on Si has been investigated by optical microscopy and atomic force microscopy. Heteroepitaxial growth of 3C-SiC films on Si (001) and (111) substrates has been performed using hexamethyldisilane in a resistance-heated chemical vapor deposition reactor. The influence of the orientation of the Si substrate in determining the shape of the voids has clearly been observed. In addition, the growth period and the growth-temperature have been considered as the major parameters to control the size, density and shape of the voids. Generally, voids are faceted along {111} planes, but depending upon growth conditions, other facets with higher surface energy have also been observed. Finally the size and density of the voids are remarkably reduced, by suitable growth technique.