Fabrication of polymer-based micro devices: Formulation and study of the paste

Abstract

We investigate in the present work the fabrication of polymer-based micro-fluidic and micromechanical devices using sacrificial, resistive/conductive pastes, through a screen-printing process. An organic sacrificial paste is first screen-printed onto a substrate, building the future empty space (channels, cavities…) where it lies. Then, a resistive paste based on thermosetting polymer resin and graphite is deposited onto the previous layer. Finally, the sacrificial paste is removed at 150°C by sublimation through the composite, thus yielding the desired pattern. For such applications, the key is naturally the formulation of the pastes. In a previous work, we already proposed a potential formulation for the organic sacrificial paste, based on polyols [1]. In the present paper, we will focus on the formulation of the cover paste, which must be adapted rheologically for the screen-printing process, but also chemically due to strong potential interactions between the sacrificial layer and the over-layer. Finally, micro-devices such as simple fluidic channels and suspended structures were produced and shown to be operational, demonstrating the high potential of our process.

Effect of Uniformly Applied Force and Molecular Characteristics of a Polymer Chain on Its Adhesion to Graphene Substrates

“…A graphene substrate is chosen because it results in a well-defined, regular substrate structure. We note that graphite-based nanoparticles have also been in use for adhesive formulations . The behavior of polyethylene on graphene substrates is perhaps the simplest of systems that allows us to focus on the role of substrate interactions with the polymer and polymer–polymer interactions (both of which are tunable through the simulation parameters) and their roles in debonding mechanisms and the strength of the bond.…”