<p dir="ltr">The rapid evolution of semiconductor technology, driven by the limitations of Moore's Law, necessitates innovative approaches to enhance device performance and miniaturization. This thesis explores the advancement of three-dimensional integrated circuits (3D-ICs) using flexible glass-based substrates, focusing on their application in extreme environments. Flexible glass emerges as a promising material for 3D-IC packaging due to its superior electrical insulation, thermal stability, chemical resistance, and mechanical strength. These properties are critical for maintaining device reliability and functionality under harsh conditions such as high temperatures, humidity, and radiation. Their unique properties make them particularly suited for applications in aerospace, military, and automotive industries, where electronics must endure severe operational environments. The research presented in this thesis provides a comprehensive examination of the processes involved in fabricating flexible glass-based 3D-ICs, detailing methodologies for integrating semiconductor components onto a flexible glass substrate using common platform technology (CPT). This approach ensures compatibility across diverse systems and enhances the scalability and cost-effectiveness of 3D-IC solutions. Experimental results indicate that 3D-ICs incorporating flexible glass substrates exhibit enhanced functionality and durability. This study underscores the transformative potential of flexible glass in revolutionizing the design and performance of future electronic systems, ensuring their operability and longevity in demanding settings. By addressing the challenges of traditional packaging materials, flexible glass represents a significant advancement in 3D-IC technology, promising to broaden the operational landscape of electronic devices and change how they are deployed across various high-stakes fields.</p>

<p dir="ltr">Following the development of laser technology in the 1960s, radiation pressure was soon employed to manipulate particles by Arthur Ashkin in the 1970s. Since then, levitated optomechanics has been widely studied across physics, engineering, chemistry, and biology. In this dissertation, we first experimentally demonstrate GHz rotation and sensing with an optically levitated nanodumbbell near a surface. Then, we propose achieving optical refrigeration below liquid nitrogen temperature using near-field Purcell enhancement.</p><p dir="ltr">The first part of this dissertation focuses on fast rotation and sensing with a non-spherical silica nanoparticle levitated near a surface. Specifically, we optically levitate a nanodumbbell at 430 nm away from a surface in high vacuum and drive it to rotate at 1.6 GHz. This corresponds to a relative linear velocity of 1.4 km/s between the tip of the nanodumbbell and the surface at sub-micrometer separation. The near-surface rotating nanodumbbell demonstrates a superior torque sensitivity of (5.0 +/- 1.1 ) x 10^-26 Nm at room temperature. Our numerical simulation shows that such an ultra-sensitive nanodumbbell levitated near nanostructures can be used to detect fundamental physics, such as Casimir torque and non-Newtonian gravity. </p><p dir="ltr">In the latter part of this dissertation, we propose that optical refrigeration of solid with anti-Stokes fluorescence can be enhanced by Purcell effect. The spontaneous emission rate of high-energy photons is Purcell enhanced by coupling with a near-field cavity. The enhanced emission shifts the mean emission wavelength and enables optical refrigeration with high-absorption cooling laser. We estimate a minimum achievable temperature of 38 K with a Yb³⁺:YLiF₄ nanocrystal near a cavity using our proposed Purcell enhanced optical refrigeration method. This method can be applied to other rare-earth ion doped materials and enable applications that require solid-state cooling below liquid nitrogen temperature.</p>

Ce travail consiste en l'étude de phénomènes optomécaniques en d'interaction spin-orbite de la lumière, en utilisant des milieux inhomogènes et anisotropes comme systèmes modèles, différents types de systèmes matériels étant considérés en pratique. En particulier,nous avons utilisé des défauts de cristaux liquides nématiques pour lesquels nous avons identifié expérimentalement d'un couple optique de nature spin-orbite conduisant à des modifications de champ d'orientation moléculaire du cristal liquide. Aussi, grâce à l'utilisation de verres nanostructurés artificiellement permettant un contrôle de l'interaction spin-orbite à la demande,nous mettons en évidence un phénomène de couple optique inverse qui est l'analogue angulaire des forces optiques dites négatives. Cet effet optomécanique contre-intuitif est démontré expérimentalement, d'une manière indirecte, grâce à la mise en place de diverses expériences de décalage en fréquence Doppler associées aux degrés de liberté de rotation. Enfin, nous présentons nos tentatives en vue de réaliser expérimentalement l'observation directe d'un couple optique inverse. Plusieurs options sont envisagées, qui comprennent à la fois des approches à base de matériaux métalliques ou diélectriques. De manière générale, cela implique la miniaturisation des systèmes considérés, ce qui est effectué à la fois à l'échelle millimétrique et micrométrique. / This work focuses on angular optomechanics driven by the spin-orbit interaction of light, using inhomogeneous and anisotropic media as model systems and different kinds of such material systems are considered in practice. In particular, we use nematic liquid crystal defects and report on the direct experimental observation of spin-orbit optical radiation torque that leads to distortion of molecular orientation pattern of the defects. Then, by using solid-state spin-orbit couplers of arbitrary order made of artificially nanostructured glasses, we unveil an optical torque reversal phenomenon that is the angular counterpart of so-called optical negative forces. This counterintuitive optomechanical effect is experimentally retrieved, in an indirect manner, via rotational Doppler frequency shift experiments. Finally, we report on our attempts to build up an experimental framework allowing the direct observation of optical torque reversal. Several options are considered, which include both metallic and dielectric approaches and involve sample miniaturization that has been explored at the millimeter and micrometer scale.

<p dir="ltr">This thesis is about the exciting discovery of a new kind of single photon emitter that<br>is suspected to occur at the interface of silicon nitride SixNy and silicon dioxide SiO2 after<br>being rapidly annealed. Since SixNy is one of the most developed platforms for integrated<br>photonics the discovery of a native emitter in this platform opened up the possibility for<br>seamless integration of these single photon emitters with photonic circuitry for the first<br>time. This seamless integration was demonstrated as is shown in Chapter 3 by creating the<br>emitters and then patterning the SixNy layer into a waveguide. This work demonstrated for<br>the first time the coupling of such single photon emitters with on-chip integrated photonics.<br>However, the integration approach demonstrated was based on the stochastic integration of<br>emitters which limits the efficiency of the devices and the possible types of devices that can<br>be designed. This is why the next stage of research focused on the development of a site-<br>controlled process for creating these single photon emitters. Remarkably, it was found that<br>if the SixNy and SiO2 are nanostructured into nanopillars and then annealed then a single<br>photon emitter forms over 65% of the time within the nanopillar! Due to the lithography<br>defined nature of this process for creating the single photon emitters the first multi-mask<br>integration process was also developed and demonstrated. This fabrication process was used<br>to demonstrate the integration of several thousand single photon emitters with complex<br>integrated photonic structures such as topology optimized couplers. These developments<br>has generated a great deal of excitement due to the inherent scalability of the approach and<br>it’s obvious applications for the development of very large scale integrated (VLSI) on-chip<br>quantum photonic systems.</p>

It is of paramount importance to our society that the environment, life style, science and amusement flourish together in a balanced way. Some trends in this direction are the increased utilization of renewable energy, like solar photovoltaics; better health care products, for example advanced biosensors; high definition TV or high resolution cameras; and novel scientific tools for better understanding of scientific observations. Advancement of micro and nanotechnologies has directly and positively impacted our stance in these application domains; one example is that of vertical periodic or aperiodic nano or micro pillar assemblies which have attracted significant research and industrial interest in recent years. In particular, Si pillars are very attractive due to the versatility of silicon. There are many potential applications of Si nanopillar/nanowire assemblies ranging from light emission, solar cells, antireflection, sensing and nonlinear optical effects. Compared to bulk, Si pillars or their assemblies have several unique properties, such as high surface to volume ratios, light localization, efficient light guiding, better light absorption, selective band of light propagation etc.      The focus of the thesis is on the fabrication of Si pillar assemblies and hierarchical ZnO nanowires on Si micro structures in top-down and bottom-up approaches and their optical properties and different applications. Here, we have investigated periodic and aperiodic Si nano and micro structure assemblies and their properties, such as light propagation, localization, and selective guiding and light-matter interaction. These properties are exploited in a few important optoelectronic/photonic applications, such as optical biosensors, broad-band anti-reflection, radial-junction solar cells, second harmonic generation and color filters.         We achieved a low average reflectivity of ~ 2.5 % with the periodic Si micropyramid-ZnO NWs hierarchical arrays. Tenfold enhancement in Raman intensity is also observed in these structures compared to planar Si. These Si microstructure-ZnO NW hierarchical structures can enhance the performance and versatility of photovoltaic devices and optical sensors. A convenient top-down fabrication of radial junction nanopillar solar cell using spin-on doping and rapid thermal annealing process is presented. Broad band suppressed reflection, on average 5%, in 300- 850 nm wavelength range and an un-optimized cell efficiency of 6.2 % are achieved. Our method can lead to a simple and low cost process for high efficiency radial junction nanopillar solar cell fabrication.            Silicon dioxide (SiO2) coated silicon nanopillar (NP) arrays are demonstrated for surface sensitive optical biosensing. Bovine serum albumin (BSA)/anti-BSA model system is used for biosensing trials by photo-spectrometry in reflection mode. Best sensitivity in terms of limit of detection of 5.2 ng/ml is determined for our nanopillar biosensor. These results are promising for surface sensitive biosensors and the technology allows integration in the CMOS platform.         Si pillar arrays used for surface second harmonic generation (SHG) experiments are shown to have a strong dependence of the SHG intensity on the pillar geometry. The surface SHG can be suitable for nonlinear silicon photonics, surface/interface studies and optical sensing.         Aperiodic Si nanopillar assemblies in PDMS matrix are demonstrated for efficient color filtering in transmission mode. These assemblies are designed using the ‘‘molecular dynamics-collision between hard sphere’’ algorithm. The designed structure is modeled in a 3D finite difference time domain (FDTD) simulation tool for optimization of color filtering properties. Transverse localization effect of light in our nanopillar color filter structures is investigated theoretically and the results are very promising to achieve image sensors with high pixel densities (~1 µm) and low crosstalk. The developed color filter is applicable as a stand-alone filter for visible color in its present form and can be adapted for displays, imaging, smart windows and aesthetic applications. / <p>QC 20160407</p>

La photonique sur silicium a le potentiel de rendre des technologies de télécommunication optiques accessibles au grand public. Alors que l’indice de réfraction élevé du silicium permet de fabriquer des circuits photoniques intégrés (CPI) compacts, il rend difficile l’injection de lumière sur les puces de silicium. Pour faciliter le transfert de lumière d’une fibre optique vers un guide d’onde en silicium, une plateforme technologique nommée coupleur évanescent optimisé pour les différences d’indice de réfraction élevées (CEIRE) a été développée à l’Université de Sherbrooke. Afin d’appuyer cette méthode d’injection, des technologies complémentaires ont également été étudiées.

Nous avons étudié la formation de nanogaps par électromigration dans des nanofils d'or. Cette technique consiste à provoquer la rupture d'un nanofil en lui appliquant de fortes densités de courant et peut être utilisée pour la caractérisation électrique de nano-objets. L'étude en temps réel du processus d'électromigration par microscopie à force atomique a permis d'apporter un éclairage nouveau de la dynamique du processus. En effet, il apparaît que la structure globale du dispositif est définie dans les premiers temps de l'électromigration et nous avons montré que cette structure est directement liée à la microstructure du film métallique. Pour la première fois, des nanogaps ont été élaborés par électromigration dans des films monocristallins. Malgré l'absence de joints de grain, il est possible de former des nanogaps dans un matériau épitaxié. L'utilisation de ces matériaux permet d'obtenir des nanogaps avec une morphologie plus reproductible. Les propriétés de transports des nanogaps obtenus à partir de films polycristallins ont été caractérisées. Les caractéristiques obtenues présentent toutes des signatures particulières, attribuées à la présence d'agrégats d'or provenant de la procédure d'électromigration et/ou de polymères issus du procédé de nanofabrication. Ces résultats montrent la difficulté à réaliser des mesures à l'échelle de la molécule unique.

Le but principal de ce travail de thèse est de proposer un matériau précurseur d'oxydes métalliques (ZrO2, TiO2, HfO2) compatible avec la technique de photolithographie interférentielle DUV. Des oxoclusters de métaux (MOC) de transitions obtenus par complexation d'un ligand organique et hydrolysé partiellement ont été proposé comme briques élémentaires pour construire ces nanostructures. Le recours à des longueurs d'onde DUV (193 nm) permet d'exciter directement les MOC, ce qui conduit à une réticulation photoinduite, et confère à la résine un caractère de photoresist négatif. Une étude spectroscopique détaillée a permis de proposer un mécanisme de photoréticulation. Cette étude s'est appuyée essentiellement sur des techniques de suivi in situ de la réaction photochimique, par ellipsométrie spectroscopique et RT-FTIR. La nanostructuration a été effectuée essentiellement par lithographie interférométrique DUV (DUV-IL) à 193 nm et étendue à la stéréolithographie biphotonique. La DUV-IL a été choisie pour son potentiel d'écriture de nanostructures sur des surfaces relativement importantes, dans des conditions standard d'atmosphère et température. De plus, dans le cas des TiOC, les nanostructures peuvent être rendues inorganiques à température ambiante par un traitement photochimique supplémentaire. Dans le cas de ZrOC et HfOC, une étape supplémentaire de recuit thermique permet d'obtenir une structure de type MO2 cristallisée.

Spintronics or electronics that utilizes the spin degree of freedom of a single charge carrier (or an ensemble of charge carriers) to store, process, sense or communicate data and information is a rapidly burgeoning field in electronics. In spintronic devices, information is encoded in the spin polarization of a single carrier (or multiple carriers) and the spin(s) of these carrier(s) are manipulated for device operation. This strategy could lead to devices with low power consumption. This dissertation investigates spin transport in one dimensional and two dimensional semiconductors, with a view to applications in spintronic devices.

The fast progress in the exploration of 2D materials such as graphene became possible due to development of fabrication techniques that allowed these materials to be protected from e.g. undesirable doping and gave rise to new functionalities realized within van der Waals heterostructures. Attracted by van der Waals interaction the constituent layers of such heterostructures preserve their exceptional electronic quality and for example in graphene allow for high electron mobility to be achieved. However, the studies of atomically thin layers such as NbSe2 that exhibit metallic behavior have been impeded by their reactivity and hence oxidation during exposure to ambient or oxidizing agents such as solvents. In this thesis, the existing heterostructure assembly technique was improved by the introduction of exfoliation and re-stacking by a fully motorized system placed in an inert atmosphere. This approach allowed us to overcome the problem of environmental degradation and create Hall bars and planar tunnel junctions from atomically thin superconducting NbSe2. Furthermore, this versatile approach allowed us to study the thickness dependence of the normal and superconducting state transport properties of NbSe2, uncovering the reduction of the superconducting energy gap and transition temperature in the thinnest samples. On the other hand, 2D materials being just 1-3 atoms thick represent an ultimate example of a membrane - thin but laterally extended object. Consisting of such atomically thin membranes the van der Waals heterostructures can be used for purposes other than the studies of electronic transport. In this work, ubiquitous bubbles occurring during van der Waals heterostructure assembly are employed as a tool to explore 2D materials' mechanical properties and mutual adhesion. This allowed us to measure Young's modulus of graphene and other 2D materials under 1-2% strain and deduce the internal pressure that can reach up to 1 GPa in sub-nanometer size bubbles.