CMOS Compatible Anodic Al2O3 Based Sensors for Bacteria Detection

AbstractRapid, real-time detection of pathogenic microorganisms is an emerging evolving field of research, especially for microorganisms that pose a major threat to public health. Alumina covered interdigitated capacitive microsensors were previously designed in our laboratory for DNA hybridization electrical detection (LOD of 30 nM target DNA). The device is constructed with standard CMOS materials. We show here that when coated with an appropriate anti- Staphylococcus aureus monoclonal antibody (MoAb), this device also permits to specifically detect this bacteria. The binding of bacteria to the microsensors induce a significant capacitance shift that is proportional to the amount of immobilized bacteria, thus enabling a possible quantitative analysis

Energy-band engineering for improved charge retention in fully self-aligned double floating-gate single-electron memories

We present a new fully self-aligned single-electron memory with a single pair of nano floating gates, made of different materials (Si and Ge). The energy barrier that prevents stored charge leakage is induced not only by quantum effects but also by the conduction-band offset that arises between Ge and Si. The dimension and position of each floating gate are well defined and controlled. The devices exhibit a long retention time and single-electron injection at room temperature

A simple method for measuring Si-Fin sidewall roughness by AFM

The gate oxide reliability and the electrical behavior of FinFETs are directly related to the surface characteristics of the fin vertical sidewalls. The surface roughness of the fin sidewalls is one of the most important structural parameters to be monitored in order to optimize the fin patterning and postetch treatments. Because of the nanometer-scale dimensions of the fins and the vertical orientation of the sidewall surface, their roughness measurement is a serious challenge. In this paper, we describe a simple and effective method for measuring the sidewall morphology of silicon fins by conventional atomic force microscopy. The present methodology has been employed to analyze fins as etched by reactive ion etching and fins repaired by sacrificial oxidation. The results show that sacrificial oxidation not only reduces the roughness of the sidewalls, but also rounds the top corners of silicon fins. The present method can also be applied to characterize sidewall roughness of other nanostructures and materials such as the polysilicon gate of transistors or nanoelectromechanical beams

SOI-CMOS compatible low-power gas sensor using sputtered and drop-coated metal-oxide active layers

In this paper, a Silicon-On-Insulator (SOI) solid-state gas-sensor with an original design of a polysilicon loop-shaped microheater fabricated on a thin-stacked dielectric membrane is presented. The microheater ensures high thermal uniformity and very low power consumption (25 mW for heating at 400 degrees C). Sensitive films are based on tin and tungsten oxides deposited either by RF sputtering or drop coating methods. The fabricated sensors are tested to a wide variety of contaminant species and promising results are obtained. The use of completely CMOS compatible TMAH-based bulk micro-machining techniques during the fabrication process, allows easy smart gas sensor integration in SOI-CMOS technology. This makes SOI-based gas-sensing devices particularly attractive for use in handheld battery-operated gas monitors

Oxide Ion Transport in Promising Cobaltites for SOC

International audienceTwo cobaltites were studied as air electrodes for Solid Oxide Cells with a Cerium Gadolinium Oxide electrolyte (CGO): Ca3Co4O9+δ, well known for its thermoelectric properties, and Ba2Co9O14. After optimisation of composition and thickness, a very good ASR of only 0.08 Ω.cm2 was obtained for the 50 wt% Ba2Co9O14 - 50 wt% 50CGO composite. In contrast, a value of 0.5 Ω.cm2 was reached for the 50 wt% Ca3Co4O9+δ - 50 wt% CGO composite. Although, Ba2Co9O14 sample contained 18O after annealing, oxide ion diffusion in this compound still has to be confirmed. In contrast, high surface exchange kinetics were measured for both Ca3Co4O9+δ and NdBaCo2O5+δ, for which mainly calcium and barium/neodymium were evidenced at the uppermost surface of the samples, whose atoms may play a key role in the mechanism of oxygen molecules dissociation

SOI-CMOS compatible low-power gas sensor using sputtered and drop-coated metal-oxide active layers

In this paper, a Silicon-On-Insulator (SOI) solid-state gas-sensor with an original design of a polysilicon loop-shaped microheater fabricated on a thin-stacked dielectric membrane is presented. The microheater ensures high thermal uniformity and very low power consumption (25 mW for heating at 400°C). Sensitive films are based on tin and tungsten oxides deposited either by RF sputtering or drop coating methods. The fabricated sensors are tested to a wide variety of contaminant species and promising results are obtained. The use of completely CMOS compatible TMAH-based bulk micro-machining techniques during the fabrication process, allows easy smart gas sensor integration in SOI-CMOS technology. This makes SOI-based gas-sensing devices particularly attractive for use in handheld battery-operated gas monitors