Characterization of thin films by a pulsed positron beam

Positron lifetime spectroscopy with an intense pulsed positron beam has been used to characterize defects in hydrogenated amorphous silicon films, porous silicon, diamond films, ion implanted SiO2, and metal‐oxide‐semiconductor samples. Both long‐lived component and short‐lived component of the positron lifetime spectra strongly depend on the deposition condition, annealing temperature, and other conditions. The relationship between positron lifetime spectra and microscopic structures is discussed.