  Since the pioneering work of S.Y. Chou et al.[1] Nano Imprint Lithography
(NIL) has emerged as a promising technique for surface patterning, opening for
numerous applications ranging from nanophotonics[2] to microfluidics[3]. NIL
basically consists in the stamping of deformable surfaces or films. Preferred
materials are thermoplastics[4] and UV curable resists[5]. So far, most papers
report on single imprinting methods for which the same surface is imprinted
only once. In the present paper, we report the imprinting of square silica
structures from simple line gratings and demonstrate how the specific
thermo-rheological behavior of ICSG resists can be harnessed to form complex
structures by sequential imprinting at low pressures.
