Surface quantification by ion implantation through a removable layer

Quantification at the surface or in the near-surface region has been diffic ult to achieve for analytical techniques such as secondary ion mass spectro metry (SIMS) and total reflection x-ray fluorescence (TXRF). Ion implantati on through a removable layer with energy selected to place the peak of the implant at the interface between the layer and the substrate can provide a known concentration of any element at the interface. When the layer is remo ved, the surface and near-surface regions of the substrate have known conce ntrations of the element of interest. Changes in the dose of the ion implan t can be used to vary the concentration at the surface. Surface roughness a fter the oxide has been removed has been considered and does not appear to be significant. Earlier studies of implants into oxide provided the data re quired to determine the implant energy. Standards have been created for bor on, phosphorus, arsenic, and nitrogen. Initial studies have also been made for magnesium, aluminum, calcium, iron, nickel, and copper. Applications ha ve been made for SIMS ultrashallow analyses, surface SIMS, time-of-flight ( TOF)-SIMS, and TXRF. Usage of this method for Auger electron spectroscopy a nd x-ray photoelectron spectroscopy quantification should also be viable. ( C) 2000 American Vacuum Society. [S0734-211X(00)07901-4].