Systems of Integrated Micro Plasma Arrays in Silicon – SIMPAS

The aim of this project is the fabrication and the characterization of integrated plasma microreactors in silicon. These microdevices can be utilized in the near future either in MEMS technology (e.g. microsensors, lab on chip, micro Total Analysis Systems'), if they are associated to the microfluidic and microelectronics components, or in plasma processing at the macroscopic scale if we are able to operate hundreds of microplasmas in parallel. Two types of demontrators (prototype A and B) are proposed within this project. They will be fabricated using the equipment of the clean room of the RTB network (mainly the Minerve/IEF facility in Orsay and/or LPN facility in Marcoussis). The two prototypes both correspond to MHCD (Micro Hollow Cathode Discharges) type microplasmas. MHCDs are non thermal and non equilibrium plasmas, which has the exceptional ability to work at atmospheric pressure or beyond in DC regime. The first of the two prototypes, which we want to make, will not be emerging. Hence, it will not be possible to flow a gaz through it. For this prototype, different chips containing microreactors of different diameters and having different geometric configurations will be realized on a same wafer. In this manner, we will be able to investigate the limit of the micro devices in terms of maximal injected power, number of microreactors working in parallel and microreactor diameter. The second prototype will consist of emerging holes, so that it will possible to work in gas flow regime. The deep silicon etching part, which will form the emerging microcavities, will be made at GREMI laboratory using a recently patented plasma cryogenic etching process, developed at GREMI. The optical and electrical characterization of these prototypes will be carried out at GREMI. An experimental setup is already partially installed at GREMI will be available to test the operation and the efficiency of the microreactors. Different diagnostics (optical spectroscopy, space and time resolved imaging, electrical diagnostics, ') will be used for the characterization. The maximum injected power and the maximum number of microplasmas functioning simultaneaously without individual ballast will be tested using this experimental setup. The aging of the miocroreactors will be studied using observation instruments such as SEM or optical microscope available in the lab. Several different gas will tested (noble gas and molecular gas). One part of the project will consist to test the two prototypes to convert volatile organic compounds. This research activity is already running in the laboratory, but using only Dielectric Barrier Discharge reactors or gliding arcs. MHCDs able to workin DC offer an interesting perspective in gas processing if we are able to operate hundreds of them in parallel to treat gas in the macroscopic scale. In parallel with the experimental part of this project, a modelization work will carried out to simulate MHCDs in collaboration with the LAPLACE lab in Toulouse, which owns an efficient code to simulate this kind of microplasmas. This project will be conducted by a team composed of four persons having a permanent position (two associate professors, one research engineer and one engineer assistant) whose complementary competences will make this project succeed. Two post docs (one year each) and one PhD student will reinforce the research team. The ambition of this project is to create and develop a new thematic at the boundary between MEMS microtechnology and plasma processes.