A method of manufacturing a semiconductor device includes the steps of
providing a semiconductor substrate (202), forming a dielectric layer
(204) over the semiconductor substrate (202), and etching a trench or a
via (206) in the dielectric layer (204) to expose a portion of the
surface of the semiconductor substrate (202). The method also includes
the step of forming a conductive layer (212, 220) within in the trench or
the via (206). The method further includes the steps of polishing a
portion of the conductive layer (220) and annealing the conductive layer
(212, 220) at a predetermined temperature. Moreover, the conductive layer
(212, 220) also includes a dopant, and the dopant diffuses substantially
to the surface of the top side of the conductive layer (212, 220) to form
a dopant oxide layer (212a, 220a) when the conductive layer (212, 220) is
annealed at the predetermined temperature and the dopant is exposed to
oxygen.