Dans les années à venir, l’industrie de la microélectronique doit développer de nouvelles filières technologiques qui pourront devenir des successeurs ou des compléments de la technologie CMOS ultime. Parmi ces technologies émergentes relevant du domaine ‘‘Beyond CMOS’’, ce travail de recherche porte sur les transistors mono-électroniques (SET) dont le fonctionnement est basé sur la quantification de la charge électrique, le transport quantique et la répulsion Coulombienne. Les SETs doivent être étudiés à trois niveaux : composants, circuits et système. Ces nouveaux composants, utilisent à leur profit le phénomène dit de blocage de Coulomb permettant le transit des électrons de manière séquentielle, afin de contrôler très précisément le courant véhiculé. Ainsi, le caractère granulaire de la charge électrique dans le transport des électrons par effet tunnel, permet d’envisager la réalisation de transistors et de cellules mémoires à haute densité d’intégration, basse consommation. L’objectif principal de ce travail de thèse est d’explorer et d’évaluer le potentiel des transistors mono-électroniques double-grille métalliques (DG-SETs) pour les circuits logiques numériques. De ce fait, les travaux de recherches proposés sont divisés en trois parties : i) le développement des outils de simulation et tout particulièrement un modèle analytique de DG-SET ; ii) la conception de circuits numériques à base de DGSETs dans une approche ‘‘cellules standards’’ ; et iii) l’exploration d’architectures logiques versatiles à base de DG-SETs en exploitant la double-grille du dispositif. Un modèle analytique pour les DG-SETs métalliques fonctionnant à température ambiante et au-delà est présenté. Ce modèle est basé sur des paramètres physiques et géométriques et implémenté en langage Verilog-A. Il est utilisable pour la conception de circuits analogiques ou numériques hybrides SET-CMOS. A l’aide de cet outil, nous avons conçu, simulé et évalué les performances de circuits logiques à base de DG-SETs afin de mettre en avant leur utilisation dans les futurs circuits ULSI. Une bibliothèque de cellules logiques, à base de DG-SETs, fonctionnant à haute température est présentée. Des résultats remarquables ont été atteints notamment en terme de consommation d’énergie. De plus, des architectures logiques telles que les blocs élémentaires pour le calcul (ALU, SRAM, etc.) ont été conçues entièrement à base de DG-SETs. La flexibilité offerte par la seconde grille du DG-SET a permis de concevoir une nouvelle famille de circuits logiques flexibles à base de portes de transmission. Une réduction du nombre de transistors par fonction et de consommation a été atteinte. Enfin, des analyses Monte-Carlo sont abordées afin de déterminer la robustesse des circuits logiques conçus à l'égard des dispersions technologiques. / In this work, we have presented a physics-based analytical SET model for hybrid SET-CMOS circuit simulations. A realistic SET modeling approach has been used to provide a compact SET model that takes several conduction mechanisms into account and closely matches experimental SET characteristics. The model is implemented in Verilog-A language, and can provide suitable environment to simulate hybrid SET-CMOS architectures. We have presented logic circuit design technique based on double gate metallic SET at room temperature. We have also shown the flexibility that the second gate can bring in order to configure the SET into P-type and N-type. Given that the same device is utilized, the circuit design approach exhibits regularity of the logic gate that simplifies the design process and leads to reduce the increasing process variations. Afterwards, we have addressed a new Boolean logic family based on DG-SET. An evaluation of the performance metrics have been carried out to quantify SET technology at the circuit level and compared to advanced CMOS technology nodes. SET-based static memory was achieved and performances metrics have been discussed. At the architectural level, we have investigated both full DG-SET based arithmetic logic blocks (FA and ALU) and programmable logic circuits to emphasize the low power aspect of the technology. The extra power reduction of SETs based logic gates compared to the CMOS makes this technology much attractive for ultra-low power embedded applications. In this way, architectures based on SETs may offer a new computational paradigm with low power consumption and low voltage operation. We have also addressed a flexible logic design methodology based on DG-SET transmission gates. Unlike conventional design approach, the XOR / XNOR behavior can be efficiently implemented with only 4 transistors. Moreover, this approach allows obtaining reconfigurable XOR / XNOR gates by swapping the cell biasing. Given that the same device is utilized, the structure can be physically implemented and established in a regular manner. Finally, complex logic gates based on DG-SET transmission gates offer an improvement in terms of transistor device count and power consumption compared to standard complementary SETs implementations.Process variations are introduced through our model enabling then a statistical study to better estimate the SET-based circuit performances and robustness. SET features low power but limited operating frequency, i.e. the parasitics linked to the interconnects reduce the circuit operating frequency as the SET Ion current is limited to the nA range. In term of perspectives: i) detailed studying the impact on SET-based logic cells of process variation and random back ground charge ii) considering multi-level computational model and their associate architectures iii) investigating new computation paradigms (neuro-inspired architectures, quantum cellular automata) should be considered for future works.

Finding an optimal solution for the logic circuit design problem is challenging and time-consuming especially for complex logic circuits. As the number of logic gates increases the task of designing optimal logic circuits extends beyond human capability. A number of evolutionary algorithms have been invented to tackle a range of optimisation problems, including logic circuit design. This dissertation explores two of these evolutionary algorithms i.e. Gene Expression Programming (GEP) and Multi Expression Programming (MEP) with the aim of integrating their strengths into a new Genetic Programming (GP) algorithm. GEP was invented by Candida Ferreira in 1999 and published in 2001 [8]. The GEP algorithm inherits the advantages of the Genetic Algorithm (GA) and GP, and it uses a simple encoding method to solve complex problems [6, 32]. While GEP emerged as powerful due to its simplicity in implementation and exibility in genetic operations, it is not without weaknesses. Some of these inherent weaknesses are discussed in [1, 6, 21]. Like GEP, MEP is a GP-variant that uses linear chromosomes of xed length [23]. A unique feature of MEP is its ability to store multiple solutions of a problem in a single chromosome. MEP also has an ability to implement code-reuse which is achieved through its representation which allow multiple references to a single sub-structure. This dissertation proposes a new GP algorithm, Improved Gene Expression Programming (IGEP) which im- proves the performance of the traditional GEP by combining the code-reuse capability and simplicity of gene encoding method from MEP and GEP, respectively. The results obtained using the IGEP and the traditional GEP show that the two algorithms are comparable in terms of the success rate when applied on simple problems such as basic logic functions. However, for complex problems such as one-bit Full Adder (FA) and AND-OR Arithmetic Logic Unit (ALU) the IGEP performs better than the traditional GEP due to the code-reuse in IGEP / Mathematical Sciences / M. Sc. (Applied Mathematics)