SEM and AFM analysis of light point defects

The paper describes methods of the microscopic analyses on the light point defects (LPD), which are usually counted with the optical wafer inspection systems. Special attention is paid on the observations of the LPD's originating from the actual IC process steps. Then the LPD count per wafer can be very low e.g. after an efficient cleaning step. The localization of the LM of the interest is realized through the litographic fabrication of small dot marks, which enable the navigation on the bare substrate surfaces. The marks are fabricated using light field patterns, when the marked wafers are suitable for the studies on the manufacturing processes. On the other hand the marks fabricated with the dark field pattern can be be used for the studies of the IC fabrication processes. Examples on the LP13 distributions on the wafer, SEM/EDX spectra of the LPD's and COP studies with the AFM are presented. Finally, the possibilities of the adhesion studies of the particles are shortly discussed.