Preparation and application of monodisperse spherical polymethylsilsesquioxane (PMSQ) beads by sol-gel method

We have prepared monodisperse polymethylsilsesquioxane (PMSQ) microspheres with the diameters of 0.5–4 μm in aqueous solution by a sol-gel method. The as-prepared PMSQ beads are modified with hexamethyldisiloxane (HMDSO) under highly acidic conditions to form hydrophobic trimethylsilylated spheres. A continuous lift-up method was developed to perform monolayer self-assembly ordered arrays of the hydrophobic PMSQ microspheres on the large area substrate (>14 cm in length). We further reported a novel patterning method to control the sizes and the pitches of the arrayed microscale patterns independently. The technology to fabricate the large area arrayed microstructures may find applications in the manufacture of flexible micro-devices.