Characteristics of A.C Electroluminescence in ZnGa2O4:Mn2+ Thin film Devices

Abstract

Green emitting alternating current thin film electroluminescent devices were fabricated on glass substrates in the conventional MISIM structure using ZnGa 2 O 4 :Mn as the active layer. The devices were fabricated varying the deposition time of the active/ phosphor layer at two different substrate temperatures, 500 and 600 C. The active layer and top dielectric layer were deposited using rf magnetron sputtering technique. All devices gave an emission in the green region of the visible spectrum even without any post deposition annealing. The EL emission could be de-convoluted into two=three peaks attributed to the 4 T 1 -6 A 1 transition of Mn 2þ centers at various sites in the host lattice. The intensity of the 502 nm EL emission was found to increase with active layer thickness. The luminance versus voltage plots exhibit an increase in threshold voltage with increase in phosphor layer thickness. The purity of the EL emissions is gauged using CIE coordinates that are found to lie in the green region of the chromaticity diagram. V

Transition Metal Doped Smart Glass with Pressure and Temperature Sensitive Luminescence

“…6 A1 → 4 G( 4 T2g), and 4 T1( 4 G) → 6 A1( 6 S) electronic transitions, respectively. [20][21][22][23][24][25] The drastic decrease in the spectral broadening and appearance of sharp fingerprint peaks is probably originated from the selective incorporation of Mn 2+ inside the nanocrystalline phase, thus indicating the occurrence of collective orientation of dopant during glass relaxation. Electron paramagnetic resonance (EPR) spectroscopy was employed to further clarify the exact chemical environment around Mn 2+ dopant and the results are shown in Figure 2b.…”

Electroluminescent characteristics of ZnGa2O4:Dy3+ thin film devices fabricated on glass substrates

“…There are several works 17–21 which report the fabrication of TFEL devices by depositing the active ZnGa 2 O 4 :Mn 2+ emitting layers onto thick ceramic sheets of BaTiO 3 using rf magnetron sputtering accompanied by high temperature post‐annealing treatments. Recently, we reported the fabrication of green emitting ZnGa 2 O 4 :Mn 2+ TFEL devices on glass substrates without any post‐deposition annealing 22. In the present work, white light generating alternating current driven TFEL devices were fabricated using ZnGa 2 O 4 :Dy 3+ as the active emitting layer on low temperature glass substrates without any post‐deposition treatments.…”