Cleaning results at the best - Megasonic system with submersible transducer
In co-operation with the Research Center Karlsruhe (IMT), megasonic cleaning of silicon micromechanic structures was examined for the company IBM in Rüschlikon. The chips are 500 µm thick, 3 mm long, and at their front a free-standing silicon cantilever, which is 5 µm thick and 300 µm long. A pointed tip is integrated vertically on the silicon cantilever (for applications in scanning probe microscopy). The aim of the examination was to remove resist residues from the surface, without damaging the extremely fragile silicon beam or tip.
Laser structured film before cleaning
Laser structured film after cleaning with Megasonic energy
A Kapton film is covered with a primary coating approx. 1 µm thick, on which was structured by a laser. The ablation residues shown in the left Fig. were to be removed. Cleaning was carried out at room temperature in demineralized water with a wetting agent and at an intensity of 10 W/cm2.
The ablation could be removed without any damage to the structures or the primary coating.
Chip with silicon cantilever before Megasonic supported cleaning
Chip with silicon cantilever after Megasonic supported cleaning