Electrically stable carbon nanotube yarn under tensile strain

We report a highly stable electrical conductance of a compact and well-oriented carbon nanotube yarn under tensile strain. The gauge factor of the yarn was found to be extremely small of approximately 0.15 thanks to the improvements in the dry spinning process, includingmultiweb spinning and heat treatment. The threshold strain εs, below which the yarn retains its electrical conductance stability, has also been determined to be approximately 15 × 103 ppm. Owing to its highly stable resistance under mechanical strain, the yarn has a good potential as a wiring material for niche applications,where lightweight and resistance stability are required

A Wearable, Bending-Insensitive Respiration Sensor Using Highly Oriented Carbon Nanotube Film

Recently, wearable electronics for health monitoring have been demonstrated with considerable benefits for early-stage disease detection. This article reports a flexible, bending-insensitive, bio-compatible and lightweight respiration sensor. The sensor consists of highly oriented carbon nanotube (HO-CNT) films embedded between electro-spun polyacrylonitrile (PAN) layers. By aligning carbon nanotubes between the PAN layers, the sensor exhibits a high sensitivity towards airflow (340 mV/(m/s)) and excellent flexibility and robustness. In addition, the HO-CNT sensor is insensitive to mechanical bending, making it suitable for wearable applications. We successfully demonstrated the attachment of the sensor to the human philtrum for real-time monitoring of the respiration quality. These results indicate the potential of HO-CNT flow sensor for ubiquitous personal health care applications

Capteurs intégrés pour la fiabilisation des technologies d'encapsulation en microélectronique

L’entreprise IBM a lancé en 2014 en partenariat avec l’Université de Sherbrooke, un projet de recherche pour introduire de l’intelligence, c’est-à-dire des capteurs, dans des modules micro-électroniques. Le projet vise, à partir des données des capteurs, l’optimisation des procédés d’assemblage, l’amélioration de la fiabilité ainsi que la surveillance in situ des systèmes informatiques de haute performance et de télécommunications. Mon projet consiste à concevoir, caractériser, puis intégrer 109 micro-capteurs, de dimensions 1 x 100 x 100 µm3, de température, humidité et contrainte sur une puce électronique de 2 x 2 cm2. L’objectif est d’obtenir en temps réel la répartition de l’humidité, la température et la contrainte dans l’assemblage, en environnement sévère. Les capteurs à base de nanotubes de carbone réalisés sont très sensibles à l’humidité et la température, avec par exemple une variation de 50% de la grandeur de sortie du capteur pour une variation de -40 à 140 °C. J’ai proposé une méthode novatrice à partir des propriétés de l’impédance du capteur permettant la séparation de la réponse à la température de celle à l’humidité.Abstract: IBM is combining forces with the Université de Sherbrooke to introduce intelligence, which are sensors, in microelectronics module. The project is to make the assembly process of a chip more robust thanks to the sensor data. These microelectronics modules are used in highperformance computing servers or telecommunications. The objectives are to design, characterize and embed 109 micro-sensors, having dimensions below 1 x 100 x 100 μm3. These micro-sensors will be on chip and measure temperature, moisture and strain. Thus these micro-sensors will give the spatial distribution of temperature, moisture and strain into the microelectronics module in severe environments. The carbon nanotube-based sensor realized are very sensitive to moisture and temperature, as example the output quantity value of the sensors is reduced by 50 per cent with a temperature excursions from -40 to 140 ℃. I developed a novel method to separate the temperature response from the moisture one, using the impedance properties of the sensor