Multiphysics systems and microsystems
An integrated system for instrumentation is composed of two specific subsets:
- a transducer that converts a physical quantity into an electrical signal,
- the instrumental chain that performs signal conditioning (amplification, processing, handling) of the transducer's electrical signal.
Most of the research topics in that area are strongly related to applications and are often based on industrial partnerships. Our main research activities focus on single-chip co-integration of transducers and their dedicated instrumental chains. In particular, ICube's SMH team has been developing advanced skills in the fields of mixed-signal, low-power, low-noise, ultra-fast systems design and complex signal processing.
Integrated magnetic sensors
These activities concern the development of CMOS technology-compatible high-resolution magnetic sensors and mainly on Hall effect-based sensors that can measure one, two or three axis magnetic field components.
Silicon Hall effect sensors typically allow the measuring of both static and dynamic magnetic fields with resolution in the range of 10µT (for comparison purpose, the Earth magnetic field in Strasbourg is about 47 µT). This level of performance is usually achieved with Horizontal Hall Devices (HHD), i.e. transducers that are sensitive to the component that is perpendicular to the surface of the chip. 2D or 3D magnetic field sensors require the use of Vertical Hall Devices (VHD), i.e. sensitive to the component that is parallel to the surface of the chip, and are usually implemented in high-voltage compatible technologies to reach the same level of performance as HHDs. We have developed the first high-performance low-voltage CMOS technology compatible VHD (LV-VHD). Our most recent LV-VHD achieves best performance with about 50 µT resolution.
We have also been investigating a promising new device called the CHOPFET. The CHOPFET is a MAGFET-based (magnetic field-effect transistor) structure that allows the applying of the “spinning current” technique, so far applied to Hall devices only. This opens new perspective in terms of ultra-low power and ultra-high resolution fully CMOS compatible magnetic sensors.
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Related projects
The principal project related to magnetic field sensors research activities are:
- development of a catheter magnetic navigation system for X-ray-based endovascular surgery
- development of a system dedicated to accurately locate surgery tools in IRM environment
- development of a galvanomagnetic (contactless) current sensor for industrial applications
- development of an ECG-Hall sensor for ECG signal measurement and processing in IRM environment
Fast imagers
This activity aims at developing efficient devices dedicated to measure transient light phenomenons in the time domain, typically between 1 ms (digital CCD camera, intensified and shut) and 1 ps (streak camera), for scientific and industrial investigation purpose.
We have grown advanced experience in the field of instrumentation systems for optical metrology with both spatial and temporal resolution. In particular, we have been working on streak camera systems, which have extremely fast light phenomenons measurement capabilities. These systems have incomparable direct light measurement performance and can also be adapted for measuring spatial or spectral variations.
Related projects
Our results lead to the development of a promising technology based on optical tomography of near-infrared diffusing environments, currently in use for medical research.