WP2: Ion implantation and silicidation

Understanding the formation of silicide alloys through a combination of DFT calculations and advanced experimental characterisations
SiGe/Si interface after laser annealing observed by Transmission Electron Microscopy

Work package 2 focuses on fabrication technology processes related to dopant implantation and activation, solid phase epitaxial regrowth and silicidation of metal contacts. Through a better understanding of these processes at the atomic scale, we aim to improve the predictivity of classical models and also to develop new state-of-the-art modelling tools more appropriate regarding the constraints imposed by the nanosized SiGe based devices and very low temperature processes.

The scope of WP2 will therefore be to achieve advanced models according to two actions:

Advanced calibration of lattice kinetic Monte Carlo (LKMC) models. In particular, the aim will be to review the set of calibration parameters with an accurate atomistic description in SiGe. During implantation, the model in which the thermal vibrations in the lattice will be introduced, will be able to capture both the effects of deformation generated by damage accumulation, the amorphization depths and the remaining damage. In the case of SPER in particular for heavily doped SiGe, several dependencies exist: the enhancement and retardation of recrystallisation by dopants, as well as the snow-plowing and clustering of dopants at the amorphous/crystalline interface, the influence of crystal orientation and strain dependence, but also the regrowth of defects need to be addressed together.

Develop a new formalism for LKMC models to accurately and efficiently handle the silicidation process. The simulation of silicidation is one of the most challenging tasks of the project as we have to describe multiple structural transitions due to the sequence of several alloys formed as the deposition occurs. The new model capable of simulating both intermixing reactions and diffusion reactions at the different interfaces allows us to understand the interface effects and phase transformation at the interface.

These achievements will be possible through a close discussion between simulations and experimental results.

WP2 coordinator: Anne Hemeryck, LAAS-CNRS