An embodiment of the invention is a method to reduce light induced corrosion
and
re-deposition of a metal, 8, (such as copper) that is used to make the interconnect
wiring during the semiconductor manufacturing process. The light induced corrosion
and re-deposition is caused by the exposure of a P-N junction to light, causing
a photovoltaic effect. A photon-blocking layer, 13, is used in the invention
to reduce the amount of exposure of the P-N junction to light. The photon blocking
layer, 13, of the invention may be a direct band-gap material with a band-gap
energy that is less than the lower edge of the energy spectrum of a typical light
source used in the semiconductor manufacturing facility (typically less than 1.7 eV).