PMMA RIE: LIGA technique
Hot embossing is an easy method for the reproduction
of microstructures. Under vacuum, a molding tool is
pressed into a heated thermoplastic polymer.
For subsequent electroforming of metallic complementary
structures, a residual polymer layer that inevitably remains
between substrate and molding tool has to be removed by RIE.
heigth of PMMA structure: 150µm
thickness of removed residual layer: 30µm
narrowest trenches: 8µm
thinnest PMMA-walls: 10µm
vertical etch rate: 6µm/h
horizontal etch rate: 0,7µm/h