AVS 52nd International Symposium
    Applied Surface Science Thursday Sessions
       Session AS+TF-ThA

Paper AS+TF-ThA8
Extending Defect Root-Cause Analysis to sub-100nm in-film Particle Contamination

Thursday, November 3, 2005, 4:20 pm, Room 206

Session: Thin Film Characterization II
Presenter: C. Lazik, Applied Materials, Inc.
Authors: C. Lazik, Applied Materials, Inc.
Y. Uritsky, Applied Materials, Inc.
Correspondent: Click to Email
Scanning Electron Microscopy (SEM) in combination with Energy Dispersive X-Ray Spectroscopy (EDX) is essential for effective root-cause particle analysis in the semiconductor industry and forms the core of commercial defect review tools (DRT). In many cases, however, particularly for small (<0.1µm) in-film particles located within or under deposited films, the standard DRT approach is less straightforward because of (i) uncertainty in the position of the defect 'core' within the film and/or (ii) poor SEM contrast in dielectric films. These effects ultimately limit the assurance that the electron beam is focused on the defect "core" during automated spectrum acquisition. In addition, the defect geometry may preclude the subtraction of an EDX background spectrum. We present here several examples related to the analysis of ~ 50nm "bump" defects, each of similar surface morphology, encountered following the deposition of one or more dielectric films. Providing a suitable analysis of the particle cross-section enabled the classification of the defect based upon its location within the film-stack as well as the defect formation mechanism (e.g. gas-phase nucleation, arcing). In each case, the defects were analyzed initially by top-down SEM/EDX followed by cross-sectional analysis using the focused ion beam (FIB) with only limited success. Extended Auger (PHI Smart-300 DRT) and/or TEM analysis on FIB prepared samples proved critical in yielding accurate root-cause analysis. Details will be discussed in presentation, but the general conclusion is that the integration of FIB/TEM into the modern DRT platform is necessary.