A standard CMOS process is used to fabricate optical, optoelectronic and electronic devices at the same time on a monolithic integrated circuit. FIG. 6 shows a polysilicon and silicon dioxide light scattering element formed on a silicon waveguide. The polysilicon light scatterer is formed on the core of the waveguide with a silicon dioxide layer between the polysilicon and the core. A standard CMOS process is used to form the waveguide and the light scattering element. FIG. 6A is a table summarizing the elements of the light scatterer and the waveguide of FIG. 6 and the CMOS transistors of FIGS. 1 and 2, which are formed from the same materials at the same time on the same substrate. Forming multiple light scatterers on the core of a waveguide can make a grating coupler.