Développement de l'imagerie à un pixel aux fréquences électromagnétiques térahertz (THz) avec l'utilisation d'un modulateur de type microsystème électromécaniques (MEMS)

Abstract

The Terahertz (THZ) domain is a technology in which performances and applications have multiplied over the last two decades. The enormous progress made has opened the door to many scientific advances and, in certain cases, to the first industrial THz applications. In this context, THz modulation is increasingly explored for many applications, such as imaging, communication, spectroscopy, etc. This work aims to contribute to the advancement of existing THz modulation methods by presenting new applications of THz modulation using a piezoelectric micromachined ultrasonic transducers (PMUT) as well as by demonstrating a new method of THz communication using a digital micro-mirror device (DMD) and an echelon mirror. The final goal of the research presented was to enable THz imaging using a PMUT modulator. The text begins with a literature review covering different methods of THz emission and detection. The literature review then details the THz spectroscopy, the different existing THz modulation methods and concludes with the possibility to use these modulations in a THz imaging context. Following the literature review, the fabrication of the PMUT devices used, the hypotheses and experimental configurations as well as the design of the circuit and the control program of the PMUT array are presented in the methodology section of the thesis. The results of the various experiments performed are then also presented in the results section. Since the application of imaging by acquisition to a compressed pixel could not be performed for technical reasons, this chapter ends with the results of the characterization of the PMUT array and its controller, followed by a conclusion on its functionality. Finally, this thesis concludes with a summary of the various research achievements presented in this thesis, followed by recommendations on possible improvements to the various systems designed to obtain better results, to correct certain defects or to explain the future applications allowed by the technology demonstrated in this text.

Date	12 Sept 2022
Original language	French
Awarding Institution	École de technologie supérieure
Supervisor	François Blanchard (Supervisor)