The invention relates to processes for coating a surface with a crosslinked polyelectrolytes multilayer film incorporating a protein, preferably a growth factor type protein. The bumpless semiconductor device is provided with electrode pads 2 on the surface thereof and with a passivation film 3 at the periphery of the electrode pads 2, and conductive particles 4 are metallically bonded to the electric pads 2. The input waveguides and the output waveguides are arranged to provide crosstalk between optical signals carried on the output waveguides.