Vacancy-type defects in electroplated Cu films probed by using a monoenergetic positron beam

Positron annihilation was used to probe vacancy-type defects in electroplated Cu films. The observed increase in the S value was attributed to grain growth at room temperature and the resultant increase in the fraction of positrons annihilated inside grains. As such, the annihilation characteristic of positrons trapped by grain boundaries was close to that for plastically deformed Cu.