کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5448263 | 1511773 | 2017 | 6 صفحه PDF | دانلود رایگان |
- The properties of the films strongly depend on target to substrate distance.
- High quality films were obtained for target to substrate distance of 4Â cm.
- Excitation wavelength of 454Â nm resulted in more efficient emission.
- All the films show high absorbance in the visible region.
The influence of target to substrate distance (dts) on the structural, morphological and photoluminescence (PL) properties of commercially obtained KY3F10:Ho3+ phosphor thin films prepared by pulsed laser deposition is investigated for dts values in the range of 4-7Â cm. Analysis of XRD indicates that high crystalline quality film with largest grain size is obtained for target to substrate distance of 4Â cm. Decrease in the thickness of the films is observed at larger target to substrate distances. This is attributed to the increased hemispherical expansion of the laser induced plasma plume at larger distances reducing the particle flux of the target species over a substrate area. Main PL emission at 540Â nm due to the 5F4â5I8 and 5S2â5I8 transitions of Ho3+ is investigated using four excitation wavelengths namely: 362, 416, 454 and 486Â nm. The highest PL intensity occurs at excitation of 454Â nm for all target to substrate distances considered. All the films are characterized by low reflectance and high absorption in the visible region.
Journal: Materials Chemistry and Physics - Volume 190, 1 April 2017, Pages 62-67