Characterizing SIMS transient effects apparent in matrix secondary ion signals from silicon under 1 keV Cs+ impact

The low energy Si2 , Si3 and Si4 secondary ion signals resulting from Cs+ impact on Si appear to scale with the Cs uptake noted over the SIMS transient region in a manner consistent with the electron tunneling model. These populations, particularly Si3 and Si4 also exhibit a relative insensitivity to the presence of O (shown once sputter rate variations are accounted for). Profiles that more closely match the expected Si concentration gradient from a native oxide terminated Si wafer present within the SIMS transient region can also be obtained by simply dividing the Si3 or Si4 secondary ion intensities by the Si2 intensities. This suggests a possible alternative route for reducing transient effects present in the negative secondary ion populations from Si wafers