GAS-INDUCED SWELLING OF BERYLLIUM IMPLANTED WITH DEUTERIUM IONS

An extensive TEM study of the microstructure of Be TIP-30 irradiated w ith 3 and 10 keV D ions up to fluences, Phi, in the range from 3 x 10( 20) to 8 x 10(21) D/m(2) at temperatures, T-irr = 300, 500 and 700 K h as been carried out. Depth distributions of deuterium in a form of sep arate D atoms and D-2 molecules have been investigated by means of SIM S (secondary ion mass spectrometry) and RGA (residual gas analysis) me thods, correspondingly. D ion implantation is accompanied by blisterin g and gives rise to processes of gas-induced cavitation which are very sensitive to the irradiation temperature. At T-irr = 300 K tiny gas b ubbles (about 1 nm in size) pressurized with molecular deuterium are d eveloped with parameters resembling those of helium bubbles in Be. Irr adiation at T-irr greater than or equal to 500 K leads to the appearan ce of coarse deuterium-filled cavities which can form in sub-surface l ayers different kinds of oblate labyrinth structures. Questions of ree mission, thermal desorption and trapping of deuterium in Be have been discussed.