Secondary ion mass spectrometry (SIMS) is now routinely employed to obtain depth profiles in polymer films on silicon substrates, where diffusion, segregation, and ordering of deuterated polymer blend components are typically examined with a depth resolution of less than 100 Angstrom. In some cases, diffusion or segregation behavior near the silicon surface is influenced by the extent of surface oxidation. There is also the potential for remnant moisture at the polymer/silicon interface to influence the redistribution of blend components. The effect of standard wet chemical wafer cleaning procedures on the polystyrene/silicon interface is investigated here. Deuterated solutions are employed to allow detection of remnant moisture from the cleaning/etching steps, and to indicate the extent of hydrogen termination at the polystyrene/silicon interface. Implant standards and deuterated polystyrene blends are employed to quantify the detected interfacial contaminants. The SIMS data indicate that the surface is effectively terminated by approximately one monolayer of hydrogen after an HF etch step, and by a thin oxide layer after an HCl/peroxide etch, in accord with numerous studies. There is no evidence of remnant moisture. Interfacial deuterium and oxygen are stable under 190 degrees C anneals. The absence of CD- secondary ions at the interface indicates that the interfacial deuterium does not become associated with adjacent polystyrene chains. Low levels of fluorine are also monitored, and the integrated fluorine concentration at the polystyrene/silicon interface is less than 0.01 monolayers of coverage.