Preparation And Properties Of Phosphor In Glass Film On Regularly Nanoscale Textured Glass Substrate

It is well known that LEDs can be widely applied in display backlighting,headlamps,and indoor illuminations due to their reliability,and lower power consumption.With the development of society,people have higher requirements for lighting quality.However,LEDs have some problems such as unstable illumination,uneven light emission,which greatly limit the development of LED.All-inorganic packaging materials are one of the important directions for LED development in the future,and can solve the above problems well.Firstly,a novel route to modify the luminescent performances of Ce:Y₃Al₅O₁₂（YAG）phosphor-in-glass（PiG）films were proposed in this work,where the PiG films were coated on regularly nanoscale textured glass substrate through spin coating technique.The XRD patterns of PiG thick films indicated that no impurity or secondary phases and the YAG crystalline phase can stay original.The substrate can not only improve the optical uniformity and enhance luminous efficacy by minimizing total internal reflection（TIR）,but reinforce the diffuse reflection light to improve visual comfort.The results show that the quantum yield（QY）and luminous efficacy of the film on textured glass substrate increase by 22.9%and11.18%,compared with the flat substrate.These results may bring an inspiring insight to prepare remote phosphor with different spectral performance on regularly textured surface for remote white LEDs.Then,a series of Lu_2.94-xY_xAl₅O₁₂:Ce_0.06（0≤x≤0.7）phosphors and the corresponding phosphor in glass films on regular textured glass substrate have been prepared by solid-state reaction method.SEM images show that phosphor particles are homogenously distributed within the glass matrix and keep their original morphology,suggesting the PiG films were synthesized as expected.Moreover,the luminescent characteristics of phosphor and phosphor-in-glass film are both systematically investigated in this work.As the increase of Lu³⁺,the emission wavelength shifts from 530 to 510 nm,the correlated color temperature gradually increased from 4627K to 4853K,and the color rendering index also enhanced from79.7 to 81.4,and the chromaticity coordinates are from yellow to green areas.These results may bring an inspiring insight to control the luminescent spectrum for remote LEDs.