SiGe HBTs Optimization for Wireless Power Amplifier Applications

This paper deals with SiGe HBTs optimization for power amplifier applications dedicated to wireless communications. In this work, we investigate the fT-BVCEO tradeoff by various collector optimization schemes such as epilayer thickness and dopant concentration, and SIC and CAP characteristics. Furthermore, a new trapezoidal base Germanium (Ge) profile is proposed. Thanks to this profile, precise control of Ge content at the metallurgical emitter-base junction is obtained. Gain stability is obtained for a wide range of temperatures through tuning the emitter-base junction Ge percent. Finally, a comprehensive investigation of Ge introduction into the collector (backside Ge profile) is conducted in order to improve the fT values at high injection levels

Formation de couches minces de semi-conducteurs et contrôle intégré dans une machine mono-plaque, multi-chambres 300 mm

Les travaux présentés s'inscrivent dans le cadre du développement et de la caractérisation des procédés de début de fabrication des dispositifs électroniques et optoélectroniques sur des plaques de silicium de 300 mm de diamètre. Ces travaux ont été réalisés dans un système mono-plaque équipé d'une chambre de traitements thermiques rapides, d'une chambre de dépôts chimiques en phase vapeur et d'une chambre de refroidissement qui accueille également un ellipsomètre spectroscopique. Outre la détection des procédés défectueux, ce qui devient essentiel avec le coût des plaques 300 mm, l'intégration d'un outil de métrologie dans un système thermique permet de caractériser les couches avant leur exposition à l'air et donc de suivre la croissance des films très minces (inférieur à 1 nm). La formation de modules critiques des transistors MOS a été étudiée : assemblage du module de canal (épitaxie Si et hétéro-épitaxie SiGe à basse température), du module de grille (croissance d'un oxyde mince nitruré et dépôt de poly-Si) et du module de jonctions p+/n ultra-fines pour la source et le drain (épitaxie en phase solide). Des études prospectives ont été menées sur la croissance auto-organisée des îlots quantiques de Si sur SiO2 pour améliorer les performances des mémoires de type Flash. Puis la croissance auto-organisée des îlots de Ge sur Si pour la réalisation de dispositifs optoélectroniques sur si avec une technologie compatible avec la microélectronique a été étudiée. L'ellipsométrie spectroscopique, associée à des techniques de microscopie, a permis de décrire les mécanismes intervenant lors de la croissance de ces îlots (mode Stranski-Krastanov) lors de leur encapsulation par du Si et lors de l'empilement de plusieurs plan d'îlots.Studies presented are driven by the development and the characterization on 300 mm silicon wafers of new front-end processes in electronic and optoelectronic devices. The system used is a 300 mm single wafer cluster tool equipped with a rapid thermal processor, a chemical vapor deposition chamber and a cool-clown chamber. A Spectroscopy Ellipsometer is integrated in the cool-clown chamber in order to monitor grown or deposited thin films. In addition to process control, which is mandatory given the high cost of 300 mm wafers, the integration of an optical metrology tool in the cluster tool allows characterization of films without air exposure, and hence the study of ultra-thin films (< 1 nm). The formation of some critical modules of MOS transistors has been studied: the channel module (low temperature Si epitaxy and SiGe alloys hetero-epitaxy), the gate stack module (ultra-thin nitride oxide growth and polysilicon deposition) and Source/Drain module with shallow p+/n junctions (solid phase epitaxy). More advanced studies have been dedicated to silicon-based quantum dots growth. The objective is to create small and self-organized structures without any photolithography processes. Si dots on Si0 , obtained by optimizing nucleation processes, were first studied. Then self-organized growth of Ge dots on Si for optoelectronic devices using a technology compatible with microelectronics has been assessed. Spectroscopie Ellipsometry, correlated to physical characterization, has been used to describe mechanisms occurring during Ge dots growth (Stranski-Krastanov mode), during dots capping with Si, and during stacking of dots layers.VILLEURBANNE-DOC'INSA LYON (692662301) / SudocSudocFranceF

SiGe HBT design for CMOS compatible SOI

International audienc

The endopolygalacturonase 1 from botrytis cinerea activates grapevine defense reactions unrelated to its enzyumatic activity

International audienc

The endopolygalacturonase 1 from botrytis cinerea activates grapevine defense reactions unrelated to its enzyumatic activity

International audienc

The endopolygalacturonase 1 from botrytis cinerea activates grapevine defense reactions unrelated to its enzyumatic activity

International audienc

Characterization of a new, nonpathogenic mutant of Botrytis cinerea with impaired plant colonization capacity

International audienceBotrytis cinerea is a necrotrophic pathogen that attacks more than 200 plant species.Here, the nonpathogenic mutant A336, obtained via insertional mutagenesis, was characterized.Mutant A336 was nonpathogenic on leaves and fruits, on intact and wounded tissue, while still able to penetrate the host plant. It grew normally in vitro on rich media but its conidiation pattern was altered. The mutant did not produce oxalic acid and exhibited a modified regulation of the production of some secreted proteins (acid protease 1 and endopolygalacturonase 1). Culture filtrates of the mutant triggered an important oxidative burst in grapevine ( Vitis vinifera ) suspension cells, and the mutant–plant interaction resulted in the formation of hypersensitive response-like necrosis. Genetic segregation analyses revealed that the pathogenicity phenotype was linked to a single locus, but showed that the mutated gene was not tagged by the plasmid pAN7-1.Mutant A336 is the first oxalate-deficient mutant to be described in B. cinerea and it differs from all the nonpathogenic B. cinerea mutants described to date

The grapevine flagellin receptor VvFLS2 differentially recognizes flagellin-derived epitopes from the endophytic growth-promoting bacterium Burkholderia phytofirmans and plant pathogenic bacteria

The role of flagellin perception in the context of plant beneficial bacteria still remains unclear. Here, we characterized the flagellin sensing system flg22-FLAGELLIN SENSING 2 (FLS2) in grapevine, and analyzed the flagellin perception in the interaction with the endophytic plant growth-promoting rhizobacterium (PGPR) Burkholderia phytofirmans. • The functionality of the grapevine FLS2 receptor, VvFLS2, was demonstrated by complementation assays in the Arabidopsis thaliana fls2 mutant, which restored flg22-induced H₂O₂ production and growth inhibition. Using synthetic flg22 peptides from different bacterial origins, we compared recognition specificities between VvFLS2 and AtFLS2. • In grapevine, flg22-triggered immune responses are conserved and led to partial resistance against Botrytis cinerea. Unlike flg22 peptides derived from Pseudomonas aeruginosa or Xanthomonas campestris, flg22 peptide derived from B. phytofirmans triggered only a small oxidative burst, weak and transient defense gene induction and no growth inhibition in grapevine. Although, in Arabidopsis, all the flg22 epitopes exhibited similar biological activities, the expression of VvFLS2 into the fls2 background conferred differential flg22 responses characteristic for grapevine. • These results demonstrate that VvFLS2 differentially recognizes flg22 from different bacteria, and suggest that flagellin from the beneficial PGPR B. phytofirmans has evolved to evade this grapevine immune recognition system