THE CLEAN ROOM OF ESPCI
An example of a microchannel realised in PDMS in the MMN group. This kind of realization is currently achieved by students coming for a few months in the group.
This nanosculpure has been exposed at the Frieze Art Fair of London in 2006, by artist Louis Greaud. The work was realized by V. Studer and D. Bartolo in the clean room of ESPCI.
Since 2006, a clean room, 40 m2 large, class 10000, located in the microfluidics group, is operationnal. This clean room has benefited from grants from the Region, ESPCI and the Ministery of Research. The clean room belongs to a network including ENS, Paris VI and ESPCI called “Reseau Paris Centre”. The network, was set up by the Ministery of Reseearch in 2005, Since then, it has been supported by national programs,. The network is dedicated to offer to researchers and students working in Paris the possibility to carry out microfabrication projects on a fast time scale and that do not necessitate the sophisticated capabilities of large clean rooms, such as IEF or LPN.
The ESPCI clean room is classical in its conception: it includes the basic equipment for lithography (aligner, spin coater) and other equipments such as profilometer, metal deposition apparatus, UV oven. The clean room is managed by Hervé WILLAIME. It was celebrated officially on February 1st, 2007 in the presence of J. Prost, Mme Pourteau (first adjunct to the Mayor of Paris), and institute representatives.
The clean room is now running in good conditions, under the responsability of Hervé WILLAIME, with the participation of all the members of the MMN group, students and postdocs, who remarkably share the load. One must emphasize that the effort of these students and postdocs is considerable and we are very grateful to them. The clean room is used by several groups coming from ESPCI and ENS – we count eleven groups at the moment – and the list of users includes fifty persons approximately. We strive so as researchers can use it on a fast time scale basis. In practice the time it takes to be trained and become a user of a particular equipment is a matter of days.
We specifically use two technologies that benefit from the controlled conditions offered by the clean room: PDMS (PolydimethylSiloxane) and photocuring polymers. Concerning PDMS technology we use simple moulding or more sophisticated techniques such as MSL (MultiLayer Soft Lithography). An example is shown in Fig 1a. More recently we developed a particular effort to control PDMS surface properties. Photocuring polymer technology came in the lab under the desire of working with highly viscous fluids and therefore operating with substantially large pressures. The paricular version of the technology that is now currently used in our group was invented by G. Degré, D. Bartolo and V. Studer. It gave rise to a CNRS patent.
Incidentally, we used the clean room for an artistic project – led by a professional artist Louis Greaud - that was presented in a London Frieze Art Fair last year (see Picture above). There is no particularly outstanding technological performance to accomplish here, but it was an opportunity for us, beyond the perhaps modest artistic contribution, to exchange, react and deliver on a short time scale.