Characterization of SiO2 films grown on Si substrates by monoenergetic positron beams A. UEDONO, L. WEI, S. TANIGAWA, R. SUZUKI, H. OHGAKI and T. MIKADO J. Phys. IV France, 03 C4 (1993) C4-177-C4-183 DOI: 10.1051/jp4:1993424