Enhancement of the green, visible Tb3+ luminescence from Tb-doped silicon-rich silicon oxide by C co-doping

Abstract

The effect of C co-doping on the Tb3+ luminescence from Tb-doped silicon-rich silicon oxide (SRSO) films is investigated. Tb-doped SRSO films co-doped with C (SRSO:C) were deposited by electron cyclotron resonance plasma-enhanced chemical vapor deposition. The Tb3+ photoluminescence intensity is enhanced by the presence of nanocluster Si (nc-Si), and C co-doping further increases the Tb3+ photoluminescence intensity by more than an order of magnitude. The maximum enhancement is observed at the C content of similar to5 at. %, at which the Tb3+ luminescence is bright enough to be observed by the naked eye under ambient conditions. The 543 nm Tb3+ lifetimes were in the range of 0.5-1.2 ms, comparable to those from Tb-doped silica. Based on the results, we conclude that nanometer-sized nc-Si can excite Tb3+ ions via an Auger-type energy transfer, and that C co-doping greatly increases the efficiency of such exciton-mediated excitation of Tb3+. (C) 2004 American Institute of Physics.