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Recent time-of-flight secondary ion mass spectrometry (ToF-SIMS) studies using primary cluster ion sources such as Au n + , SF n + , Bi n + or C 60 + have shown polyatomic ions to be more appropriate for the detection of high mass molecular secondary ions than monoatomic ion sources like Ga + , thanks to secondary ion yield and ion formation efficiency enhancements. This work is part of a study aiming at improving molecular compound quantification at the surface of microelectronics industry substrates by taking advantage of a polyatomic ion source in ToF-SIMS analysis. It focuses on the case of a phthalate-related contamination. Fundamental parameters like secondary ion yield, damage cross section and secondary ion efficiency were studied as a function of the size and the energy of the primary ions. The substrate composition influence on the ToF-SIMS results was also studied by comparing several substrates of interest in the microelectronics industry such as silicon wafers and low dielectric constant materials 5iO x CyH z . Phthalate-related secondary ions detected at the surface of the contaminated surfaces were compared and a fragmentation pathway of the di-isononyl phthalate (DNP) molecule was determined. A drastic improvement of the secondary ion yield was provided when using a polyatomic ion source. Furthermore, a clear increase in damage cross section was observed as a function of the secondary ion size for a given Bi n primary ion as well as an increase for a given fragment as a function of the number of Bi atoms in the Bi n aggregate. This led to a lower static limit when taking into account higher phthalate fragments and primary ions of larger size.

The detectability of amplitude modulation and spatial frequency modulation of suprathreshold sine-wave gratings was measured at retinal eccentricities ranging from 0 to 30 deg. The main conclusions to be drawn from the experimental results are: (1) for this visual task it is not possible to bring peripheral sensitivity to the same level as foveal sensitivity by scaling the stimuli with the inverse of the cortical magnification factor M. (2) Increasing the number of cycles in the carrier grating improves modulation detectability. For gratings in the periphery this holds up to the largest stimulus size used (64 cycles). In earlier investigations it has been shown that for central vision the improvement ends at about 16 cycles.