RESEARCH

Motivation

My research activities aim at structuring metallic and semiconducting thin films at the micro and nanometric scales. The main objective is to study and understand the physical properties, especially the transport mechanisms of charge carriers in films and to correlate its with structural characteristics.

Strategy

It is based on the growth of films by sputtering using pulsed gas techniques (RGPP - Reactive Gas Pulsing Process) and GLancing Angle Deposition (GLAD). The goal is to establish some correlations between the films behaviors, their anisotropic character, their structure and the produced architectures. Oxides and oxynitrides (TiO_x, WO_x, VO_x, TiO_xN_y, SiO_xN_y) are the main studied materials. Homogeneous films or nanometric periodic multilayers based-on metal/oxide type (Ti/TiO_x, W/WOx, Ta/TaO_x) can be produced by adequate control of RGPP parameters during the film growth. The role of oxygen concentration in the films or the dimensions of periodic 1D structures (thickness and number of metal/oxide periods) on the conduction properties are analyzed among others. In parallel with this pulsed gas approach, metallic thin films (Ti, W, Cr) or oxides (WO_x, VO_x, TiO_x, TaO_x) with inclined, zigzag or spiral columnar architectures are fabricated by the GLAD technique. The angle of inclination of the columns, the period of the zigzags or helical pitch can be adjusted with dimensions between a few tens and a few hundreds of nanometers through the films thickness. The simultaneous implementation of RGPP and GLAD techniques leads to the creation of original architectures.