Attenuated total reflectance (ATR)-Fourier transform infrared (FTIR) metal
surface cleanliness monitoring is disclosed. A metal surface of a semiconductor
die is impinged with an infrared (IR) beam, such as can be accomplished by using
an ATR technique. The IR beam as reflected by the metal surface is measured. For
instance, an interferogram of the reflected IR beam may be measured. A Fourier
transform of the interferogram may also be performed, in accordance with an FTIR
technique. To determine whether the metal surface is contaminated, the IR beam
as reflected is compared to a reference sample. For example, the Fourier transform
of the interferogram may be compared to the reference sample. If there is deviation
by more than a threshold, the metal surface may be concluded as being contaminated.
