Project details

Objectives

Our studies aim at understanding the mechanisms of the phase transformation of Si and Ge from the cubic 3C structure toward the hexagonal 2H and especially the involved size effects in nanowires. The transformed 2H domains may potentially become seeds for further epitaxial regrowth and integration at larger scale.

Remarkably changing the crystal phase may change the physical properties of the material especially the electronic band structure and the phonon diffusion dispersion. Thus, the unprecedented nanostructure 2H/3C nanowires may open new opportunities and functionalities that we aim to explore. In particular we investigate the potential light emission and the reduced thermal conductivity.

Project description

Below, the diagram show the objectives of the 3 workpackages and the means implemented for the project.

Side project and future

In the framework of HEXSIGE, alternative approaches were explored for the synthesis and integration of SiGe-2H (see results). The various routes may provide different applications and are now fully investigated in the following projects :