Strain tailoring in 3C-SiC heteroepitaxial layers grown on Si(100)

Due to the large differences in lattice parameters and thermal expansion coefficients, the heteroepitaxial growth of 3C-SiC on Si mainly results in highly defective layers on strongly bent wafers. The defects may not be detrimental for very basic applications, but the bow is. In this article, we review several attempts to reduce the final curvature after epitaxial growth of 3C-SiC. One is the use of the checkerboard carbonization process which creates a macroscopic balance of the stress by the formation of a regular network of compressed and tensed areas. Another approach proposes to create, in situ, a random patchwork of tensed and compressed areas during the carbonization step. The other attempts use substrates other than standard Si, namely silicon on insulator and Si-Ge substrates for compliance effect and closer thermal expansion mismatch with SiC, respectively. All techniques provoke a significant reduction of the strain in the deposited 3C-SiC layers.