Dans le présent document, nous nous intéressons aux cellules photovoltaïques en présentant un tour d'horizon sur ces dispositifs électroniques depuis la couche active, constituant le milieu absorbeur, jusqu'à leur association dans des modules pour fournir l'énergie requise par une installation. En premier lieu, nous donnons un bref survol des aspects généraux et du vocabulaire de base utilisés dans ce domaine, puis nous abordons le volet concernant les matériaux et la conversion photovoltaïques ainsi que les technologies retenues pour réaliser ces cellules. En second lieu, nous présentons les techniques de caractérisation utilisées pour contrôler la qualité des cellules réalisées ainsi que leur association en modules pour pouvoir générer des tensions et des courants utilisables en pratique. Pour finir, nous donnons quelques résultats récents et les prévisions d'une feuille de route proposée dans ce domaine

Let E be a n-dimensional vector space over a field k and ω a trivector of Λ3E. We can associate to the trivector ω several invariants either algebraic, arithmetic or geometric. In this paper we consider the following three invariants, the commutant C(ω), the complexity c(ω) and the automorphisms group Aut(ω). We show that there exists a vector space E and a trivector ω of Λ3E for which C(ω) is not a Frobenius algebra. We also show that the complexity c(ω) and the length l(ω) are equal. Finally, we prove the existence of a trivector ω such that Aut(ω) is not a FC-group.

GRAPHICAL ABSTRACT

The Equilibrium Voltage Step (EVS) technique has been used for extraction of depth and energy concentration profile of traps situated in the oxide of a lightly stressed metal-oxide-semiconductor (MOS) structure. This has been achieved up to the very near Si-SiO₂ interface. The results are discussed and compared with those obtained using charge pumping (CP) technique. A good agreement is achieved between the trap densities extracted using the two methods even though differences in the shape of the profiles can be observed. The results also very well agree with those published previously using current deep level transient spectroscopy (C-DLTS).

The performances of two full differential operational amplifiers (Op-Amps) telescopic and folded-cascode are evaluated to satisfy the stringent requirements on the amplifier to be used in a Multiplying Digital-to-Analog Converter (MDAC) stage of a pipelined ADC (Analog-to-Digital Converter). The paper shows the solutions found to reach high gain, wide bandwidth and short settling time without degrading too much the output swing. The Op-Amp specifications are extracted according to the ADC requirements, then the two Op-Amp topologies are designed, tested and their performances are compared. Simulation results show that the Op-Amp folded-cascode topology is more suitable architecture for pipelined ADC than the telescopic one. Moreover, the use of this type of Op-Amp generates an Integral Non-Linearity (INL) error less than that of the telescopic one. The analyses and simulation results are obtained using 0.18 µm AMS (Austria Mikro System) CMOS process parameters with a power supply voltage of 1.8V. The predicted performance is verified by analysis and simulations using Cadence EDA simulator.