To fabricate a (110) silicon hard master, we used anisotropic wet etching. The etching chemical for the silicon wafer was a TMAH 25% solution. We fabricated a 1x4 multimode planar waveguide splitter using the silicon hard master. Organic-inorganic hybrid materials were used as core and cladding layers of the planar waveguide splitter. The 15 μm-thick under-cladding layer was coated on a silicon substrate and baked. After the core layer was coated on the under-cladding layer, the core pattern was formed by using a hot embossing process at 100 °C and 1-3 kg/cm2. The propagation loss of the planar waveguide was 0.4 dB/cm and the insertion loss of the 1x4 planar waveguide splitter was 11.2 dB at the total splitter length of 3.5 cm.