Depth profiling of D implanted into Ti at different temperatures

Abstract

Depth proliles of 6.6 keV D⁺ implanted into titanium in the temperature range between 140 K and 500 K have been studied using the D(³He, α) H nuclear reaction.

At 140 K the trapped amount is close to 100% at low doses and reaches saturation at about 2 × 10¹⁸D/cm², whereas at room temperature no saturation could be reached up to 2 × 10¹⁹ D/cm². At higher temperatures the amount decreases until no deuterium could be detected in the surface layer above 500 K.

The depth profiles are strongly dependent on temperature. At 140 K the deuterium is found in a surface layer of about 2000 Å with a maximum ratio of deuterium to metal atoms of 2.5. At room temperature a hydride layer of TiD^1.8, forms. The thickness of the hydride layer depends on deuterium dose and extends to 1.5 μm at 2 × 10¹⁹ D/cm². At higher temperatures the atom concentrations are lower and the deuterium seems to diffuse deeply into the bulk.

These results are discussed in terms of diffusion of deuterium i n Ti and titanium hydride.