Thèse de doctorat en Physique
Sous la direction de André Vapaille.
Soutenue en 1988
à Paris 11 , en partenariat avec Université de Paris-Sud. Faculté des sciences d'Orsay (Essonne) (autre partenaire) .
Pas de résumé disponible.
NINI doping superlattices : feasibility by silicon epitaxy in ultrahigh vacuum, expected transport properties
Doping superlattices are likely to cause an enhancement of carriers mobility especially at low temperature provided that superlattice period is about a few nanometers. In the first part of our study, we show that the epitaxy in ultrahigh vacuum with doping implantation at very low energy allows achieving the envisaged structures. For that purpose we have modelised doping profiles obtained with Arsenic ions implanted under 500 ev and 1 Kev during the growth of the layer considering: the depth distribution of doping ions, their segragation tendancy towards surface and their diffusion assisted by intrinsic vacancies and implant generated vacancies. In the second part of our study we have simulated transport properties of doping superlattices NINI by means of particulary Model. The results show an enhancement of mobility wich reaches 5, 5 times of uniformly doped structure mobility. This gain of mobility decreases when layer thickness increases due to importance of perpendicular electric field