Room-temperature photoluminescence from Tb ions implanted in SiO2 on Si

The room-temperature photoluminescence (PL) of Tb3+ ions has been studied. The Tb ions were implanted into 200 nm thick SiO2 on Si wafers. To achieve a uniform Tb distribution, the implantations were performed at 50, 100, and 190 keV to a total dose of 8.8 x 10(14)-1.3 x 10(16) ions/cm(2), resulting in Tb concentrations of 0.18-2.7 at. %. The PL spectrum consists of sharp lines due to the Tb3+ intra-4f transitions and a broadband due to SiO2 defects. The samples were annealed at temperatures ranging from 600 to 1050 degrees C. Up to 900 degrees C, the annealing procedure improves the PL yield; at temperatures higher than 1000 degrees C, the PL yield drops again at high dose. The PL spectra show noticeable influence of Tb-Tb crossrelaxation, which favors the green PL over the blue PL. (C) 1998 American Institute of Physics. [S0021-8979(98)08119-5].