Comparison of Submicron Particle Analysis by Auger Electron Spectroscopy, Time-of-Flight Secondary Ion Mass Spectrometry, and Secondary Electron Microscopy With Energy Dispersive X-Ray Spectroscopy.
Comparison of Submicron Particle Analysis by Auger
Electron Spectroscopy, Time-of-Flight Secondary Ion Mass
Spectrometry, and Secondary Electron Microscopy With
Energy Dispersive X-Ray Spectroscopy.
Childs, K. D.; Narum, D.; LaVanier, L. A.; Lindley, P.
M.; Schueler, B. W.; Mulholland, G. W.; Diebold, A. C.
Journal of Vacuum Science and Technology A: Vacuum,
Surfaces, and Films, Vol. 14, No. 4, 2392-2404,
spectroscopy; mass spectrometers; microscopy; x ray
spectroscopy; semiconductor devices
Particulate contamination can result in a significant
yield loss during semiconductor device fabrication. As
device design rule dimensions decrease the critical
defect size also decreases, resulting in the need to
analyze smaller defects. Current manufacturing
requirements include analysis of sub-0.5-mum defects,
with analysis of sub-0.1-mum defects expected in the
near future. This article investigates the particle
analysis capabilities of Auger electron spectroscopy,
time-of-flight secondary ion mass spectrometry, and
energy dispersive x-ray spectroscopy during scanning
electron microscopy (SEM/EDS). In order to evaluate
each method carefully, a standard set of samples was
prepared and analyzed. These samples consist of 0.5-,
0.3-, and 0.1-mum Al and Al2O3 deposited on 1-in. Si
wafers. Although all the methods observed an Al signal,
a semiquantitative gauge of capability based on the
relative strengths of particle versus substrate signal
is provided. The dependence of the sample-to-substrate
signal on primary electron energy is examined for both
EDS and Auger analyses. The ability to distinguish
metallic Al particles from Al oxide particles for the
three techniques is also discussed.