Principal Investigator :

Gérard Ben Assayag ()
CEMES (NMAT)

Type of project : Collaborative Project

Partner team(s) :

LPCNO (Nanotech)

Date (start/end) : 2012 - 2015

Résumé

Ion implantation is a major technique used in semiconductor technology to dope and to fabricate junctions in modern micro and nano-electronics. It is also used for material surface treatment for biocompatibility, and the Ion Beam Synthesis (IBS) of new nanomaterials. The principle is to introduce impurities in a bulk material with a concentration which is not negligible with respect to the matrix to modify its local stoechiometry. When the concentration is larger than the solubility limits a phase separation assisted or not by a thermal treatment occurs. Compared to other growth techniques, this non-equilibrium thermodynamic method leads to unique new material fabrication capabilities.

Since 15 years the ultra low energy (ULE) 200A2 Varian implanter of CEMES is devoted to the synthesis of nanoparticles and nanocrystals in dielectric or crystalline matrix. This machine has been modified in 1995 by adding a homemade electrostatic decelerator to provide a high quality ion beam in the extended ultralow energy range (from 0.5 to 200keV). Depending on the implantation conditions (dose/energy), a 2D-layer (ULE-IBS) or a band of Ncx (medium energy-IBS) embedded in the matrix can be created. For more complex structures, masked implantation is a straightforward method to create and organize in-plane submicron patterns of Ncx features. We developed this method in collaboration with the LPCNO and we demonstrated that 3D structures can be directly obtained for nano-electronic, magnetic or plasmonic devices.

The IBYS project aims to update our very original capabilities of ion beam synthesis in the ultralow energy range (ULE-IBS). Available ion implanters, especially those dedicated to the microelectronic industry, are not adapted to a research environment (cost / maintenance / flexibility). The Toulouse equipment is unique among the “open platforms” in Europe thanks to its low energy range. The refurbishing of our system to get a more reliable electronic and physical environment is thus imperative to ensure the development of new research and educational projects. In particular, a higher efficiency in nanomaterial synthesis will be achieved by adding a variable temperature sample holder for a better control on the diffusion of implanted species and on the growth kinetics of nanocrystals (NCs). The scientific objectives are supported through several ANR and European projects described below. This project will strengthen the long time and fruitful collaboration between CEMES, LPCNO and INSA (AIME) as local actor and IMEL Institute “Demokritos” (Greece) in the development of ULE-IBS of NCs and 3D patterning for memories, electronic/plasmonic devices, and in advanced formation on nanoelectronics.