Matthieu Denoual

Accurate double-height micromolding method for three-dimensional polydimethylsiloxane structures

A fabrication method for making accurate double-height micromolds is presented. Fine features of the micromold are transferred to a three-dimensional poly-dimethylsiloxane (PDMS) microfluidic membrane. The accuracy of features is within 1.55% and the maximum aspect ratio is 7. In this work, the first layer of the micromolds is made directly on silicon wafers by inductively coupled plasma reactive ion etching (ICP-RIE). The second layer is added by photolithography of SU-8 negative photoresist on top of the first layer. This method allows the fabrication of micromolds having wall dimensions as small as 3 µm that was not previously achievable. Such dimensions are required in biological microfluidic systems to reduce the amount of chemicals or to confine cells to a desired position.

MicroBolometer on Polymer Membrane with Heat Feedback Control for Non Radiative Applications

This paper presents a microbolometer on a polymer membrane using heat feedback control. The target application of this device is basically infrared (IR) measurement in a wide wavelength range but can be extended to various purposes in particular chemical detection applications. A special attention was paid on characterisation and signal/noise ratio (SNR) study to optimize the performances. The interest of this work stands in the usage of thermal feedback with a microbolometer easily realized on a polymer membrane without any coolant and the proposed applications in chemical detection at room temperature.

Controlling Cell Development by Microfluidic Techniques: A Step Towards Whole-Cell Biosensors with Defined Biological Features

Several microfluidic systems were designed to accommodate cell cultures and control some aspects of cell development. In particular, the development of neuronal networks was guided over microelectrode arrays, and electrical activity of the cells was recorded over more than four weeks. Further work is currently being carried out to control some topological features of P19 cell populations during their differentiation into either neuron-like cells or cardiac myocytes.

Opportunities of CMOS-MEMS integration through LSI foundry and open facility

Since the 2000s, several countries have established micro- and nanofabrication platforms for the research and education community as national projects. By combining such platforms with VLSI multichip foundry services, various integrated devices, referred to as“CMOS-MEMS”, can be realized without constructing an entire cleanroom. In this paper, we summarize MEMS-last postprocess schemes for CMOS devices on a bulk silicon wafer as well as on a silicon-on-insulator (SOI) wafer using an open-access cleanroom of the Nanotechnology Platform of MEXT Japan. The integration devices presented in this article are free-standing structures and postprocess isolated LSI devices. Postprocess issues are identified with their solutions, such as the reactive ion etching (RIE) lag for dry release and the impact of the deep RIE (DRIE) postprocess on transistor characteristics. Integration with nonsilicon materials is proposed as one of the future directions.

Smart Bolometer: Toward Monolithic Bolometer with Smart Functions

The content of this chapter refers to uncooled resistive bolometers amd the challenge that consists in their integration into monolithic devices exhibiting smart functions. Uncooled resistive bolometers are the essential constitutive element of the majority of existing uncooled infrared imaging systems; they are referred to as microbolometer pixels in that type of application where matrixes of such elementary devices are used. uncooled bolometers represent more than 95% of the market of infrared imaging systems in 2010 (yole 2010) and infrared imaging systems are required for more and more applications.

Selective Epitaxial Growth for Buried Microchannels in Monocrystalline Silicon

A simple and single-step technique is presented for the formation of buried channels in monocrystalline silicon wafers. The channels are formed by surface migration of silicon during the selective epitaxial growth of monocrystalline silicon. Various buried-channel shapes and sizes from 1 to 30 µm were formed. This technique is compatible with semiconductor industry processes and allows postprocessing for the integration of microelectronics circuits. The applications targeting heat pipes for integrated circuits or microfluidic channels for microsystems are numerous and promising.

Single vegetal cell handling and fixing in a microfluidic device

The basic advantage of the microfluidic systems is that they enable reducing consumption of biological material and chemicals. But another major advantage of the microfluidic systems, not widely explored so far, is that with feature sizes reduced toward the size of cells, one can easily handle and fix a single cell. The interest of single cell handling and fixing appears when one wants to study biochemical exchanges between single cells or internal biochemical reactions inside an isolated cell. This work uses the shape of the microfluidc device to control the migration and placement of single vegetal cells. Three-dimensional micro-molding and poly-dimethylsiloxane (PDMS) patterning techniques have been used to realize device prototypes. Double-height micro-molds are made of thick negative photoresist (SU8) Experiments have been undergone to optimize fluid rate flow and cell concentration regarding to right cell placement percentage. The PDMS prototypes systems confirm the good operation of the design to migrate cells, place and fix them. The placement rate, even if it is enough for statistical biochemical experiments, will be improved by the use of new material. New material will allow to get rid of air bubbles due to PDMS long-term hydrophobicity that render up to 25% settlement places unserviceable.