Sims studies of the adsorption of O2, CO and CO2 on titanium using low primary energies

The influence of the adsorption of O₂, CO and CO₂ on secondary ion yields from titanium has been examined using 500 eV primary argon ions. Secondary ion energy distributions were also measured. Electron-induced desorption was used as an auxiliary technique. For oxygen adsorption there is agreement with measurements using other techniques and the adsorption process is shown to occur in two stages, an initial rapid chemisorption regime followed by an oxide regime. For carbon monoxide adsorption, the measurements suggest that dissociation does not occur significantly at room temperature. For CO₂, the results are more complex. Complete dissociation seems unlikely but there may be partial dissociation. Some tentative generalizations are made concenrning the influence of adsorption on secondary ion yields.