Erbium-doped Y 2O 3 thin films were synthesized by combining radical-enhanced atomic layer deposition (REALD) of Y 2O 3 and Er 2O 3 in an alternating fashion at 350°C. The Er doping level was precisely controlled to range from 6 to 14 at.% by varying the ratio of Y 2O 3:Er 2O 3 cycles during deposition. At 350°C, the films were found to be polycrystalline, showing a preferential growth direction in the  direction. Room-temperature photoluminescence (PL) at 1.54 μm, characteristic of the Er 3+ intra 4f transition, was observed in a 500-Å Er-doped (6 at.%) Y 2O 3 film, showing well resolved Stark features indicating the proper incorporation of Er in the Y 2O 3 host. Extended X-ray absorption fine structure (EXAFS) analysis revealed a six-fold coordination of Er by O in all samples, suggesting that the PL quenching observed at high Er concentration (>8 at.%) is likely dominated by Er ion-ion interaction and not by Er immiscibility in the Y 2O 3 host. The effective absorption cross section for Er 3+ ions incorporated in Y 2O 3 was determined to be ∼10 -18 cm 2, about three orders of magnitude larger than the direct optical absorption cross section reported for Er 3+ ions in a stoichiometric SiO 2 host.
|期刊||Proceedings of SPIE - The International Society for Optical Engineering|
|出版狀態||Published - 2005|
|事件||Nanofabrication: Technologies, Devices, and Applications II - Boston, MA, United States|
持續時間: 2005 十月 23 → 2005 十月 25
All Science Journal Classification (ASJC) codes