Characterization of thin films and solid surfaces using proton- induced x-ray emission.
Sartwell-BD; Campbell-AB III
Avondale, MD: U.S. Department of the Interior, Bureau of Mines, RI 8455, 1980 Jan; :1-22
The Bureau of Mines is using characteristic x-rays produced by proton bombardment of a solid surface to provide quantitative compositional analyses of surface layers of metals. An integral x- ray yield equation has been developed that quantitatively relates the measured x-ray yield to the thickness of thin films ranging from less than a monolayer to several thousand angstroms. The use of the integral yield equation is demonstrated for the growth of a thin film by vacuum evaporation. Results are presented that show how proton-induced x-ray emission (pixe) has been used to determine the oxidation kinetics of iron that had been implanted with several different species of heavy ions. The sensitivity of pixe for the measurement of very-thin-film growth kinetics is demonstrated from studies of the effect of fractional monolayer coverages of sulfur on the initial oxidation kinetics of iron. Results are also presented in which pixe has been used to study the redistribution of alloying elements in components of a gas turbine that had fractured due to corrosion fatigue. By combining pixe with low-energy ion sputtering, quantitative composition depth profiles of surface layers are obtained. Examples are presented for the profiling of iron samples implanted with 25-kev nickel ions and for a platinum coating on an fe-5cr substrate.
Corrosion; Iron; Kinetics; Metal coatings; Numerical solution; Oxidation; Samples; Surfaces; X ray analysis
IH; Report of Investigations
NTIS Accession No.
Avondale, MD: U.S. Department of the Interior, Bureau of Mines, RI 8455