Microfabrication and scale effect studies for a magnetic micromanipulation system

The development of the biological research requires the implementation of new micromanipulation devices of single cell. The device presented here allows the manipulation of micro-objects where diameter varies from 20 /spl mu/m to 1 mm, in a drop of water between two glass slides. Micro-objects are moved thanks to a magnetic micromanipulator. Although magnetic force is a volumic force, we prove that it is still important in the microworld compared to adhesion forces, or weight. Magnetic micromanipulators are small nickel pieces whose sizes varies from 10 /spl times/ 10 /spl times/ 5 /spl mu/m/sup 3/ to 400 /spl times/ 400 /spl times/ 20 /spl mu/m/sup 3/. We present an original microfabrication process to fabricate and to isolate the microscopic nickel pieces.