Suppression of phosphor‐glass reactions in YAG:Ce phosphor‐embedded glasses

Abstract

For high-power white LED applications, YAG:Ce-based yellow phosphors were embedded in a low-T g Bi 2 O 3 -B 2 O 5 -ZnO-Sb 2 O 5 glass (BiG) by sintering route. A high-T g silicate glass (SiG) was also used for comparison. Dense (porosity<2%) phosphor-glass composites were obtained after sintered at 800°C (for SiG) and 325°C (for BiG). XRD quantitative analysis indicates that the loss of phosphor content is in the range of 2.5%-22%, caused by partial dissolution of phosphor particles into the glass matrix during sintering. The element distribution across the interface and within the reaction zone between phosphor and glass was analyzed by TEM/SEM-EDS. The intrinsic emission characteristic of YAG:Ce is nearly not altered, possibly resulted from the slight modification of the YAG phase during sintering. Thus the final emission intensity of the sintered body is mainly determined by the residual amount of the YAG:Ce phase. Replace the high-T g SiG glass by the low-T g BiG glass, prenitridize the YAG:Ce phosphor, and change the sintering atmosphere from air to N 2 suppress the loss of phosphor during sintering. Therefore, the resulting loss of emission intensity of the phosphor-embedded glass material can be reduced to only about 1.8%. K E Y W O R D Sbismuthate glass, interface reaction, nitridizing, phosphor in glass, YAG

Gradient refractive index structure of phosphor‐in‐glass coating for packaging of white LEDs

“…As the fourth‐generation lighting source, white light‐emitting diodes (w‐LEDs) excel over traditional lighting in terms of longer lifetime, higher reliability, lower power consumption, and more environment‐friendly . Generally, w‐LEDs are fabricated by GaN‐based blue chips coated with commercial Y 3 Al 5 O 12 :Ce 3+ (YAG:Ce) yellow phosphor .…”

Anomalous enhancement of photoluminescence intensity of sintered YAG:Ce particles‐embedded glasses

“…According to the contrast difference in the image and the EDS results, the reaction zone between YAG and glass was determined. The detail element distribution and formation mechanism for similar reaction zones are discussed in our previous study . The variation in the thickness of the reaction zone with the heating temperature is shown in Figure .…”

Glass Ceramic Phosphors: Towards Long‐Lifetime High‐Power White Light‐Emitting‐Diode Applications–A Review

“…Schematic diagrams to show the element distribution within the reaction zone in e) BiG‐ and h) SiG‐GCs. Reproduced with permission . Copyright 2016, Wiley‐VCH.…”

“…Blue-excited warm w-LED [118] Sol-gel Reproduced with permission. [39] Copyright 2016, Wiley-VCH. Figure 9.…”

“…studied the effect of YAG:Ce 3+ prenitridizing treatment on the glass‐phosphor reactions and the resulting luminescence properties of YAG:Ce 3+ PiG color converter based on the glass system of Bi 2 O 3 ‐B 2 O 3 ‐ZnO‐Sb 2 O 5 (BiG). In the study, a high‐T g silicate glass (SiG) was also used for comparison. It is found the BiG glass retains more phosphor phase (83%–87%) than that (78%–82%) using the SiG glass, due to the lower co‐sintering temperature.…”