Both adsorbed reacted surface oxygen (surface oxide) and the dynamic implantation range of primary oxygen ions have been shown to influence secondary ion yields and complicate the interpretation of secondary ion mass spectrometry (SIMS) in‐depth analysis within the first few hundred angstroms of the surface. Surface oxide chemically enhances the secondary ion yield over the first few tens of angstroms. After removal of the surface oxide, the secondary ion emission yield reaches a minimum level, and enhancement of the secondary ion yield is then a function of the distribution of the implanted oxygen concentration. These effects have been studied on arsenic‐implant‐diffused and unimplanted single‐crystal silicon.