Defects in 30 keV Er+-implanted SiO2/Si studied by positron annihilation and cathodoluminescence

Defects in SiO2 (48 nm)/Si induced by 30 keV Er ion implantation were studi ed by positron annihilation. Depth-selective information on defects for sam ples implanted with doses of 3.0x10(14) and 1.5x10(15) Er/cm(2) was obtaine d by a variable-energy positron beam by measuring Doppler broadening of pos itron annihilation gamma rays as a function of incident positron energy. Co mparison of the results by Doppler broadening with those by electron spin r esonance after annealing indicates that the types of defects (which predomi nantly exist in the SiO2 layer) depend on implantation dose. The annealing temperature dependence of positron data is compared with that of the cathod oluminescence intensity at 1.54 mum, and the possible effect of defects on luminescence intensity is discussed. (C) 2001 American Institute of Physics .