This paper presents a novel way to switch dual-behavior resonator (DBR) filters without any additional active surface-mount components. By using a semiconductor substrate, we were able to ...simultaneously co-design the filters and semiconductor distributed doped areas (ScDDAs) with integrated N+PP+ junctions as active elements. These ScDDAs act as electrical vias in the substrate, which makes it possible to have an open-circuited resonator in the OFF state and a short-circuited resonator in the ON state, and, consequently, to control the transmission zeroes of the filters. This method offers degrees of freedom as the dimensions and positions of these doped areas can be chosen to obtain the best performances. In this study, four filters were simulated and fabricated to spotlight different possibilities for the dimensions and positions of the ScDDA to control the low- or high-frequency transmission zero of the filters. The simulations were in very good agreement with the measured results. All the filters present insertion losses lower than 2 dB in the OFF and ON states, a great flexibility in the frequency choice, and good agility compared with the state of the art.
This paper presents two novel on-chip bandstop to bandpass reconfigurable filters in C and X bands. Designed on a silicon substrate, filter reconfigurability is achieved using ...semiconductor-distributed doped areas (ScDDAs), such as an N+PP+ junction integrated into the substrate. The active element is therefore co-designed with the passive parts, allowing flexibility in ScDDA size and position. This flexibility offers advantages in terms of integration, ease of manufacture, and performance. The synthesis was developed in the OFF-state in order to match with the well-known one in the ON-state. As proof of concept, 5 GHz and 10 GHz filters were built. The simulated and measured results showed good agreement in both bandpass and bandstop configurations.
Al–Si thermomigration is an attractive means to produce through-wafer isolation walls for power devices. The unintentional layers of Al2O3 formed due to the necessary oxygen-containing ambient, after ...the thermomigration process, must be removed from the surfaces of Si wafer. In this regard, both dry and wet etching recipes are investigated in this article. Residues of Al2O3 and Al–Si alloy are eliminated without additional mask by a two-step etching process. BCl3 plasma treatment is proved to be effective to strip off the aluminum oxide layer with acceptable loss of silicon and silicon dioxide. Subsequent wet etching using commercial wet solution enables to remove the rest of Al-containing residues.
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•Al2O3 is etched by inductively coupled plasma without additional mask.•BCl3 is proved to be more effective than CHF3/Ar to remove aluminum oxide.•Acceptable selectivity of Al2O3 over both Si and SiO2 is achieved with BCl3.•All residues are selectively removed by combinsing both wet and dry etches.
This paper presents two polarization reconfigurable patch antennas using semiconductor distributed doped areas (ScDDAs) as active components. One proposed antenna has a switching polarization between ...two linear ones, while the other one has a polarization able to commute from a linear to a circular one. The antennas are designed on a silicon substrate in order to have the ScDDAs integrated in the substrate, overcoming the needs of classical PIN diodes. Therefore, the proposed co-design method between the antenna and the ScDDAs permits us to optimize the global reconfigurable function, designing both parts in the same process flow. Both demonstrators have a resonant frequency of around 5 GHz. The simulated results fit well with the measured ones.
We present in this paper a novel application of porous silicon (PS) for low-power alternating current (AC) switches such as triode alternating current devices (TRIACs) frequently used to control ...small appliances (fridge, vacuum cleaner, washing machine, coffee makers, etc.). More precisely, it seems possible to benefit from the PS electrical insulation properties to ensure the OFF state of the device. Based on the technological aspects of the most commonly used AC switch peripheries physically responsible of the TRIAC blocking performances (leakage current and breakdown voltage), we suggest to isolate upper and lower junctions through the addition of a PS layer anodically etched from existing AC switch diffusion profiles. Then, we comment the voltage capability of practical samples emanating from the proposed architecture. Thanks to the characterization results of simple Al-PS-Si(P) structures, the experimental observations are interpreted, thus opening new outlooks in the field of AC switch peripheries.
This study reports on an original and efficient way to synthesize iron nanowires and cubic-shaped nanoparticles by electrochemical deposition on a mesoporous silicon host and its impact on magnetic ...properties. The selective growth of iron nanostructures inside the pores can be achieved, thanks to the presence of a native oxide layer on the pore walls, suggesting a surface-state assisted electrochemical process. Because of hydrogen coevolution, the pH of the solution controls the shape of the iron nanostructures (particles or wires) while the electrodeposition current density can be adjusted to suppress the parasitic deposition on top of the structure. Under optimal conditions, nanowires with lengths up to 2 μm are synthesized after 15 seconds of deposition. Magnetic characterization of the ferromagnetic nanowire composite exhibits an easy axis of magnetization in the pore direction due to shape anisotropy with a remanence ratio of 0.6. The shape anisotropy of the nanoparticle composite is weaker than for the nanowire composite because of the homogeneous dispersion of the particles. The versatility of the mesoporous silicon framework is thus a considerable asset to tune the nanocomposite’s magnetic properties.
Ces travaux de thèse accompagnent le développement de nouvelles architectures d’interrupteurs monolithiques bidirectionnels en courant et en tension. L’une des voies technologiques proposées consiste ...à contrôler les propriétés électriques de l’interface de soudure Si-Si. Nous avons mis en évidence la nature complexe de l’activité électrique de l’interface avec l’existence d’un continuum d’états d’énergie au caractère recombinant. L’intégration d’une telle brique technologique nécessite alors la maîtrise de la passivation/décoration de l’interface par diffusion d’impuretés. La passivation des états d’interfaces par hydrogénation a montré une amélioration des propriétés électriques globales de l’interface de soudure avec une réduction de la dispersion des paramètres électriques. Une contamination contrôlée par diffusion de platine, nous a permis d’obtenir une désactivation, voire une compensation, du phosphore à l’interface, accompagnée d’une disparition des niveaux profonds.
1-lydrophobic silicon direct wafer bonding is an interesting way to realize new devices, espccia1lhen it could substitutc for double-side lithography or give access tu buried layers during process. This study goes with the design of a monolithic switch bidirectional in current and voltage for household appliances. We investigate the electrical properties of hydrophobic silicon wafer bonded interface. We have shown the interface is composed of several electronic defects, due to lattice deformations and residual contaminations, generating deep levels with recombinant properties. Finally, this study is focused on its electrical characterization and how to control its electrical activity. Hydrogenation and platinum diffusion are performed at Iow temperature and underline the possibility to restore the phosphorus biilk doping level. Therefore, an appropriate thermal treatment could be used to passivate a bonded interface without any bulk contamination.
This article addresses a discrete tunable resonator with three different states controlled by a single DC source. The passive components are designed together with the active elements, and both are ...integrated on a silicon substrate. This method of co-design offers great flexibility in doped area sizing and positioning, allowing for easy management of novel three-state resonators based on two different doped areas (or two different surfaces of semiconductor junctions). The largest area switches from the reverse state (OFF-state) to the forward state (ON1-state), with a lower bias voltage than the smallest area (ON2-state). This concept offers some new degrees of freedom in the design of tunable microwave devices, showcased in this study by a demonstrator that can operate at three different resonant frequencies. Good agreement was obtained between simulations and measurements in the three states. Insertion losses are lower than 1.6 dB and the same for the different states.
This paper presents a novel reconfigurable polarization patch antenna designed on a silicon substrate and using integrated semiconductor distributed doped areas (ScDDAs) as active elements. The ...antenna is able to commute from a circular to a linear polarization. The co-design between the antenna and the ScDDAs results in a monolithic integration of the active elements in the substrate. This method allows to optimize the global performances in the circular and linear polarizations thanks to the flexibility of the doped area shape and position. A demonstrator is proposed from the simulations to the measurements and validates the proof of concept.
This paper deals with a patch antenna presenting a reconfigurable polarization using semiconductor distributed doped areas (ScDDAs). This on-chip antenna offers a switch able polarization between two ...linear ones. The monolithic integration of the ScDDAs as active elements directly in the substrate avoids additional components and gives design flexibility. The antenna and the ScDDAs are co-designed and manufactured in a same process flow. The commutation is achieved with a DC bias of − 2.2 V. The measured results fit well with the simulated ones.
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