Wafer-scale integration of piezoelectric actuation capabilities in nanoelectromechanical systems resonators

In this work, we demonstrate the integration of piezoelectric actuation means on arrays of nanocantilevers at the wafer scale. We use lead titanate zirconate (PZT) as piezoelectric material mainly because of its excellent actuation properties even when geometrically constrained at extreme scal

Wafer-scale integration of piezoelectric actuation capabilities in nanoelectromechanical systems resonators

In this work, we demonstrate the integration of piezoelectric actuation means on arrays of nanocantilevers at the wafer scale. We use lead titanate zirconate (PZT) as piezoelectric material mainly because of its excellent actuation properties even when geometrically constrained at extreme scal

Process management in an academic laboratory: recipe library, data access, monitoring, different tools to be implemented

International audienceThe processes developed in cleanrooms are often very specific to a particular technique, equipment or application. In academic organizations, we are sometimes facing the loss of knowledge with difficulties to take over technologies developed in the past.We propose here an approach to improve the quality of the processes developed on the photolithography resources and which will be in open access to all users of the LAAS platform. In this quality approach, several tools have been set up. First of all, we propose to develop some processes and to offer a library with a large panel ofrecipes in terms of dimensions and applications: plasma etching, deep etching, lift off, electroplating, etc. Several features have been taken into consideration: generic designs, standardized protocols, systematic characterization processes and data access via the MyFab platform management system.Secondly, we will present the methods to ensure the control of operations at different scales. For standard processes, we provide qualification operations as well as a statistical process control by using the data of the controls performed by the users. For more specific processes, a shared database is accessible to users to share process parameters.Through these different systems, which have been progressively implemented over the past 10 years, our management system has helped us to improve data sharing between users and assure quality of technological operations. These initiatives could be extended outside of the laboratory in order to share these good practices and improve knowledge sharing by working in a network

Process management in an academic laboratory: recipe library, data access, monitoring, different tools to be implemented

International audienceThe processes developed in cleanrooms are often very specific to a particular technique, equipment or application. In academic organizations, we are sometimes facing the loss of knowledge with difficulties to take over technologies developed in the past.We propose here an approach to improve the quality of the processes developed on the photolithography resources and which will be in open access to all users of the LAAS platform. In this quality approach, several tools have been set up. First of all, we propose to develop some processes and to offer a library with a large panel ofrecipes in terms of dimensions and applications: plasma etching, deep etching, lift off, electroplating, etc. Several features have been taken into consideration: generic designs, standardized protocols, systematic characterization processes and data access via the MyFab platform management system.Secondly, we will present the methods to ensure the control of operations at different scales. For standard processes, we provide qualification operations as well as a statistical process control by using the data of the controls performed by the users. For more specific processes, a shared database is accessible to users to share process parameters.Through these different systems, which have been progressively implemented over the past 10 years, our management system has helped us to improve data sharing between users and assure quality of technological operations. These initiatives could be extended outside of the laboratory in order to share these good practices and improve knowledge sharing by working in a network

Temporary adhesives for wafer bonding: deep reactive ion etching application

International audienc

Optimizing a brain-on-chip technology with nanowire based-3D electrodes to record and stimulate the neuronal activity with high resolution

National audienc

Three-dimensional closed microfluidic channel fabrication by stepper projection single step lithography: the diabolo effect

International audienceMicrofluidic devices are currently being used in many types of biochemical microsystems for the liquid phase analysis in the frame of medical applications. This paper presents a new technique for the realization of microfluidic channels using SU-8, a commonly used epoxy-based negative photo-resist. These microchannels were fabricated owing to a single stepper UV-photolithography process. By changing the process parameters, e.g. the optical focus depth and the UV exposure dose, well-defined, covered microchannels with various dimensions and aspect ratios were realized and proven to be effective for the fluid transport by capillarity. This technique can easily be used for the fabrication of microfluidic devices in microanalysis and lab-on-chip applications realm

Combining PEDOT:PSS Polymer Coating with Metallic 3D Nanowires Electrodes to Achieve High Electrochemical Performances for Neuronal Interfacing Applications

International audienceAbstract This study presents a novel approach to improve the performance of microelectrode arrays (MEAs) used for electrophysiological studies of neuronal networks. The integration of 3D nanowires (NWs) with MEAs increases the surface‐to‐volume ratio, which enables subcellular interactions and high‐resolution neuronal signal recording. However, these devices suffer from high initial interface impedance and limited charge transfer capacity due to their small effective area. To overcome these limitations, the integration of conductive polymer coatings, poly(3,4‐ethylenedioxythiophene)‐poly(styrenesulfonate) (PEDOT:PSS) is investigated as a mean of improving the charge transfer capacity and biocompatibility of MEAs. The study combines platinum silicide‐based metallic 3D nanowires electrodes with electrodeposited PEDOT:PSS coatings to deposit ultra‐thin (<50 nm) layers of conductive polymer onto metallic electrodes with very high selectivity. The polymer‐coated electrodes were fully characterized electrochemically and morphologically to establish a direct relationship between synthesis conditions, morphology, and conductive features. Results show that PEDOT‐coated electrodes exhibit thickness‐dependent improved stimulation and recording performances, offering new perspectives for neuronal interfacing with optimal cell engulfment to enable the study of neuronal activity with acute spatial and signal resolution at the sub‐cellular level