In a standard CMOS process, a layer of metallic salicide can be deposited
on those selected portions of an integrated circuit, where it is desired
to have metallic contacts for electronic components, such as transistors.
The deposition of a salicide into optical elements such as the core of an
optical waveguide or a light scatterer will damage the elements and
prevent the passage of light through those sections of the elements.
Prior to the deposition of the salicide, a salicide blocking layer is
deposited on those parts of an integrated circuit, such as on an optical
waveguide or a light scatterer, which are to be protected from damage by
the deposition of salicide. The salicide blocking layer is used as one
layer of the cladding of a silicon waveguide and a light scatterer.