화학공학소재연구정보센터
Journal of Crystal Growth, Vol.334, No.1, 138-145, 2011
Anisotropy effects during non-selective epitaxial growth of Si and SiGe materials
Recently, great improvements have been obtained on Chemical Vapor Deposition (CVD) processes and their integration in advanced MOS technologies. Actually. Si and SiGe materials realized by CVD processes are excellent candidates to provide technical solutions what ensure the continuing device performance enhancement. This work reports an extensive investigation regarding the anisotropic effects observed when Si and SiGe films are grown by CVD processes on various Si surface orientations. To focus as possible, our study on intrinsic and fundamental growth parameters, simple hydride chemistry was used for the different depositions. In this case, we have first observed that the film morphology and the film thickness strongly depend on the surface orientation. Then, we have characterized the anisotropy of the growth kinetics and proposed a model explaining its origin in our experimental conditions. This model is based on surface structure and dangling bond density considerations and, for a simple deposition illustrated by the Si epitaxy this model seems to explain the root cause of faceting appearance. Finally, compared to Si material, the SiGe hetero-epitaxy is found to be more sensitive to the anisotropic effects. Therefore, we supposed in this latter case, the influence of others mechanisms, such as mixing or growth modes. (C) 2011 Elsevier B.V. All rights reserved.