Epitaxial p-type thermoelectric perovskite oxides for integrated thermal energy harvesting

Domaine et contexte scientifique / Scientific domaine and context

Thermal management has become of major importance on microelectronic platforms. Either device temperature has to be reduced or waste thermal energy could be harvested and converted into electricity to build autonomous devices. Thermoelectric (TE) materials allow reaching both objectives, by Peltier effect or by Seebeck effect, respectively [1]. TE materials are heavily doped semiconductors, and standard TE materials are based on Te (e.g. Bi₂Te₃) [2], which are toxic, chemically unstable and expensive because of scarcity [3-4]. Oxides of perovskite structure (ABO₃) are good alternative TE materials overcoming these issues since its chemical flexibility allows a wide range of doping and thus TE property optimization by cationic substitution [3-6]. Furthermore, they can contain low toxic and abundant elements [3,7], and allow proper advanced integration on Si-based microelectronic platforms by molecular beam epitaxy (MBE) for which the leading team has a long-term international recognized expertise [8].

Objectifs de la thèse / Job description

In order to overcome the current issues of this thematic, we propose to:

1. Develop promising p-type TE oxides of perovskite-structured solid-solutions by MBE at INL (partly based on ab-initio calculations from a collaboration with C. Adessi, ILM)
2. Study and optimize the global TE properties by doping, strain, defects, couplings, and interface strategies (physical properties partly measured in collaboration with S. Pailhès and V. Giordano, ILM)
3. Develop a sustainable technological process for the fabrication of a functional integrated TE micromodule (at INL, with the support of the Nanolyon technological platform).

Funding category: Contrat doctoral



PHD title: Electronique, micro et nano-électronique, optique et laser

PHD Country: France