The invention relates to the technical field of
semiconductor manufacturing, in particular to a method for removing unreacted
nickel-
platinum alloy in self-aligned
silicide, which comprises the following steps of: a) providing a
wafer with a
metal layer on the surface; the
metal layer comprises
nickel platinum alloy; b) forming a
porous titanium dioxide layer on the surface of the
metal layer; c) removing the metal layer at normal temperature by adopting a
photocatalytic reaction; d) removing the
porous titanium dioxide layer by adopting a
hydrogen peroxide complexation reaction; and e) sequentially carrying out
impurity removal,
water washing and
drying on the surface of the
wafer to obtain the self-aligned
silicide. Compared with the prior art, the method for removing the unreacted
nickel-
platinum alloy in the self-aligned
silicide, provided by the invention, adopts specific process steps and conditions, realizes relatively good overall interaction, can remove the unreacted nickel-platinum alloy in the self-aligned silicide at normal temperature, avoids the influence of a high-temperature wet process on the
thermal stability of the nickel-
silicon compound, and improves the yield of the nickel-
silicon compound. And the
nickel silicide is not lost, so that the stability of the self-aligned silicide process is improved, and the product yield is further improved.