| AVS 66th International Symposium & Exhibition | |
| Thin Films Division | Thursday Sessions |
| Session TF-ThP |
| Session: | Thin Films Poster Session |
| Presenter: | O. Martin Ntwaeaborwa, University of the Witwatersrand, South Africa |
| Authors: | S.N. Ogugua, University of the Free State, South Africa H.C. Swart, University of the Free State, South Africa O.M. Ntwaeaborwa, University of the Witwatersrand, South Africa |
| Correspondent: | Click to Email |
Phosphors have many technological uses in applications such as solid-state lighting, optical laser, data storage, medicine, quantity control, scintillation, advertising, solar cells, theft prevention, etc. We have prepared a series of praseodymium (Pr3+) and dysprosium (Dy3+) doped mixed rare-earths oxyorthosilicate phosphors with a general formula R2SiO5 hosts (R = La, Gd or Y) using the solution combustion method. By varying the molar ratio of La to Y and Gd to Y, we modified the unit cells and the crystal field strengths of the host lattices. This modification of the crystal field of the host lattice can lead to the shifting of the emission wavelengths, increase of the rate of radiative transitions, and minimization of energy loss by non-radiative transitions. We evaluated the crystal structure and photoluminescence properties of Pr3+/Dy3+ doped R2SiO5 (R = La, Gd or Y) in powder and laser ablation deposited thin film forms. We varied several deposition parameters including partial pressure of gas (O2 and Ar), type of laser pulse, and substrate temperature using the 1064 nm Nd:YAG solid state laser. The effects of varying the La to Y/Gd ratios on the field strengths of the host lattices and the influence of the various deposition conditions on the emission colour and photoluminescent intensities will be discussed.