The present disclosure relates to a method of fabricating a semiconductor structure, the method includes forming an opening and depositing a metal layer in the opening. The depositing includes performing one or more deposition cycles, wherein each deposition cycle includes flowing a first precursor into a deposition chamber and performing an ultraviolet (UV) radiation process on the first precursor. The method further includes performing a first purging process in the deposition chamber to remove at least a portion of the first precursor, flowing a second precursor into the deposition chamber, and purging the deposition chamber to remove at least a portion of the second precursor.