DEUTERIUM TRAPPING IN EVAPORATED METAL-FILMS .1. CHARACTERIZATION OF THE TRAPPING

Using forward recoil energy spectroscopy (FRES), it was found that eva porated films of a variety of metals can absorb on the order of 1 at.% deuterium (D). This is several orders of magnitude greater than would be expected based on lattice solubility, showing that these films con tain a large concentration of defects which trap D. The nature of this trapping was studied using iron as a model system. The defects which trapped D annealed out at approximately 500 K and were present in high er concentrations in polycrystalline films than in single crystalline films. Trap concentration decreased with increasing substrate temperat ure during deposition. These results indicate that the traps may be as sociated with either voids or grain boundaries.