Tb3+ Luminescence in a-SiNx:H

Terbium doped hydrogenated amorphous silicon nitride was prepared by reactive sputtering from a silicon target partially covered with metallic Tb platelets in a Ar+N₂+H₂ atmosphere. When the samples have a high enough bandgap they present characteristic Tb³⁺ luminescence at 545, 585 and 620nm. This luminescence can be excited by an Ar⁺ laser either resonantly using the 488nm line which corresponds to the 490nm transition of the Tb³⁺ or via the a-SiN_x:H network using the 476nm line. The samples were annealed at 300, 400 and 500°C. For non-resonant excitation, the dependence of the Tb³⁺ luminescence intensity with the annealing temperature depends on the hydrogen content for a given nitrogen content.