Luminescent Properties of SrAl₂O₄:Eu Thin Films Deposited by Intense Pulsed Ion-Beam Evaporation

Abstract

SrAl2O4 activated with Eu, a long-phosphorescence material with high brightness, has been successfully deposited on Si substrates using intense pulsed ion-beam evaporation. Efficient preparation of long-phosphorescence thin films has been achieved using a high-density ablation plasma produced by the interaction of an intense pulsed ion-beam with the SrAl2O4:Eu target. The prepared SrAl2O4:Eu thin films had a polycrystalline structure without annealing and showed a typical photoluminescence of SrAl2O4:Eu at around 520 nm. Thermoluminescence (TL) measurements were carried out in order to obtain the lifetimes of the phosphorescence. In particular, TL spectra in the higher temperature region, which contributed to the long phosphorescence, were examined by the partial heating technique to evaluate the distributed trap depths and the lifetimes. The phosphorescence lifetime at 300 K for the prepared film was found to be about 180 min.

Electroluminescent ceramics excited by low electrical field

“…Based on the assumption that light emission is excited by 10 kV/cm, the excited voltage is only 1 V for SAO-E ceramics with a thickness of 1 m. Existing techniques would allow a useful 0.5-m-thick SAO-E film. 15,16 Therefore, this result has exciting implications for future development of SAO-E thin film EL devices.…”

Luminescence of Pulsed-Laser-Deposited SrAl[sub 2]O[sub 4]:Eu,Dy Thin Film and Its Role as a Stress Indicator

“…All of the films showed a growth preference in the ͓011͔ orientation, except for the 200 and 300 mTorr films in series A, and the preference was much more prominent in film S. Such a remarkable texture has never been observed in films produced by other deposition techniques such as rf sputtering 9,10 and ion-beam evaporation. [11][12][13] We believe that the texture ͓͑011͔ preferred orientation͒ of grown films is an intrinsic property of SrAl 2 O 4 crystal growth, just like some other oxides such as Y 2 O 3 and Gd 2 O 3 , showing ͓111͔ orientation preference. Then we have to verify the reason why such a nature was not observed in other films deposited by rf sputtering and ion-beam evaporation.…”

“…Thin-film-type SrAl 2 O 4 :Eu,Dy phosphors have been developed for use in electronic devices based on radio frequency, ͑rf͒ sputtering 9,10 and pulsed electron-beam evaporation. [11][12][13] However, SrAl 2 O 4 :Eu,Dy thin-film phosphors have never been considered for use as a stress indicator. The PLD technique has also never been adopted as a deposition technique in the case of an SrAl 2 O 4 :Eu,Dy thin-film phosphor, even though it is well known that PLD is a promising technique for other oxide thin-film phosphors such as Y 2 O 3 :Eu, Gd 2 O 3 :Eu, Y 2 SiO 5 :Tb, etc.…”

Persistent Luminescence in Strontium Aluminate: A Roadmap to a Brighter Future

“…[ 175 ] e) Data reproduced from. [ 176 ] f) This curve is used as a reference for a glow curve of SrAl 2 O 4 :Eu 2+ . Data reproduced from.…”