The behavior of yttrium implants in H13 steel under high temperature oxidation

The penetration depth of yttrium ions extracted at 30 kV from a metal vapor vacuum arc (MEVVA) source reaches approximately 50 nm in H13 steel. For a pre-set dose of 3×10 17 cm −2 , the retained dose decreases (1.04×10 17 –6.2×10 16 cm −2 ) with increasing beam flux (25–76 μA cm −2 ). During high temperature (600–800°C) oxidation, yttrium implants have no change in quantity, but migrate inwards and redistribute themselves. As the dose is increased (up to 1×10 18 cm −2 ) in-going yttrium is redistributed almost uniformly within the oxidation scale; when the beam flux is increased the peak of yttrium profile shifts to a much deeper position (245 nm for 76 μA cm −2 ). Yttrium redistribution is not sensitive to oxidation time. A tentative explanation is presented.