Thesis defence
Ghizlane BOUSSATOUR
Friday 12 April 2019
Institute of Electronics, Microelectronics and Nanotechnology (IEMN)
Jury:
- Elodie RICHALOT (Université Paris-Est Marne-la-Vallée, Rapporteur)
- Geneviève MAZE-MERCEUR (CEA-CESTA Le Barp, Rapporteur)
- Tuami LASRI (University of Lille, thesis supervisor)
- Pierre-Yves CRESSON (University of Lille, co-supervisor)
Summary:
| Biopolymer materials are very popular, with a wide range of applications in many fields, where they are increasingly replacing petroleum-based polymers. Given their properties, which include biocompatibility, biodegradability, flexibility and lightness, they are attracting growing interest in the field of electronics. Nevertheless, their possible integration into high-frequency electronics requires the study of important properties such as thermal conductivity and complex dielectric permittivity. In this work we focus on two biopolymers in particular, poly lactic acid (PLA) and cellulose palmitate (CP). The properties of these materials are extracted using two methods. The 3ω method for determining thermal conductivity and the two-line method for determining complex dielectric permittivity. The latter is measured over a frequency range from 0.5 to 67 GHz. These two characterisation techniques require metal lines to be made on the surface of the biopolymer films, which by their very nature do not lend themselves well to photolithography processes. Alternative processes have therefore been developed to meet this technological challenge. This experimental work is accompanied by modelling studies on both aspects, i.e. estimates of the thermal conductivity and complex dielectric permittivity of the materials investigated. Comparison of the proposed analytical and numerical models with the experimental data shows a good understanding of the problem of characterising these biopolymers. |
Abstract:
Biopolymer materials attract significant attention in many fields where they tend to replace petrosourced polymers. Thanks to their properties, such as biocompatibility, biodegradability, flexibility and lightness, biopolmyers are also increasingly used in many electronic applications. Nevertheless, their possible integration into high-frequency electronics requires the study of important properties such as thermal conductivity and dielectric complex permittivity. In this work we are interested in two biopolymers in particular, poly lactic acid (PLA) and cellulose palmitate (CP). The extraction of the properties of these materials is carried out through the implementation of two methods. The means selected are the 3ω method for the thermal conductivity and the two-line method for the dielectric complex permittivity. This latter is measured in the frequency band 0.5 - 67 GHz.
These two characterization techniques require the realization of metal lines on the surface of the biopolymer films. Since biopolymers are not compatible with classical photolithography method, an alternative processes have been developed to meet this technological challenge. This experimental work is accompanied by modeling studies on both aspects, estimates of the thermal conductivity and the complex dielectric permittivity of the investigated materials. The comparison of the proposed analytical and numerical models with the experimental data shows a good understanding of the problem of characterization of these biopolymers.
