Luminescent layer and light-emitting semiconductor device
View Patent ↗A chip-type light-emitting semiconductor device includes: a substrate 4; a blue LED 1 mounted on the substrate 4; and a luminescent layer 3 made of a mixture of yellow/yellowish phosphor particles 2 and a base material 13 (translucent resin). The yellow/yellowish phosphor particles 2 is a silicate phosphor which absorbs blue light emitted by the blue LED 1 to emit a fluorescence having a main emission peak in the wavelength range from 550 nm to 600 nm, inclusive, and which contains, as a main component, a compound expressed by the chemical formula: (Sr 1-a1-b1-x Ba a1 Ca b1 Eu x ) 2 SiO 4 (0≤a1≤0.3, 0≤b1≤0.8 and 0<x<1). The silicate phosphor particles disperse substantially evenly in the resin easily. As a result, excellent white light is obtained.
1. A luminescent layer comprising phosphor particles, ultra-fine particles and a translucent resin,
wherein the phosphor particles are dispersed within the translucent resin and primary particles of the ultra-fine particles have an average particle size in the range from 3 nm to 50 nm, both inclusive.
2. The luminescent layer of claim 1 , wherein the ultra-fine particles are thixotropy improvers.
3. The luminescent layer of claim 1 , wherein the ultra-fine particles include silicon dioxide and/or aluminum oxide.
4. The luminescent layer of claim 1 , wherein the resin is any one of an epoxy resin, an acrylic resin, a polyimide resin, a urea resin or a silicone resin.
5. The luminescent layer of claim 1 , wherein the phosphor particles have a core particle size in the range from 0.5 μm to 30 μm, both inclusive.
6. The luminescent layer of claim 5 , wherein the phosphor particles have a core particle size in the range from 1 μm to 20 μm, both inclusive.
7. The luminescent layer of claim 1 , wherein the phosphor particles are silicate phosphor particles.
8. The luminescent layer of claim 1 , wherein the luminescent layer is formed by any one of a photolithography process, a screen-printing process or a transfer process.
9. A light-emitting semiconductor device utilizing the, comprising:
a luminescent layer of claim 1 and including:
phosphor particles;
ultra-fine particles including primary particles, the primary particles having an average particle size of equal to or greater than 3 nm and equal or less than 50 nm; and
a translucent resin;
a light-emitting device in combination,; and
a supporter, wherein:
the phosphor particles are dispersed in the translucent resin,
the light-emitting device is disposed on the supporter,
the light-emitting device has a bottom surface facing the supporter, and a main light-extracting surface from which a light is extracted and opposite to the bottom surface,
the luminescent layer is in contact with the light-emitting device only at the main light-extracting surface,
the luminescent layer covers an entirety of the main light-extracting surface, and extends beyond outer edges of the light-emitting device, and
the light-emitting semiconductor device emits mixed light mixed with from light emitted from the light-emitting device and a fluorescence emitted from the phosphor particles.
10. The light-emitting semiconductor device of claim 9 , wherein the light emitted from the light-emitting device has a main emission peak in the a wavelength range greater than 430 nm and less than or equal to 500 nm, and the phosphor particles emit the fluorescence having a main emission peak in a wavelength range equal to or greater than 550 nm and equal to or less than 600 nm.
11. The light-emitting semiconductor device of claim 10 , wherein the phosphor emits a fluorescence having a main emission peak in the wavelength range from 550 nm to 600 nm, both inclusive.
12. The light-emitting semiconductor device of claim 9 , wherein the phosphor emits a fluorescence having a main emission peak in the wavelength range from 550 nm to 600 nm, both inclusive.
13. The light-emitting semiconductor device of claim 9 , wherein the light-emitting semiconductor device has a plurality of LEDs light-emitting devices, and the luminescent layer continuously covers the plurality of LEDs light-emitting devices.
14. The light-emitting semiconductor device of claim 13 9, wherein a portion of an upper surface of a portion of the luminescent layer is flat and substantially parallel to the main light extracting surface, and when viewed in plan, the portion of the upper surface is located on a light-extracting surface of inside the outer edges of the light-emitting device is flat and substantially parallel to the light-extracting surface.
15. The luminescent layer of claim 1 light-emitting semiconductor device of claim 9, wherein the ultra-fine particles have a concentration of 1.11% or more.
16. The luminescent layer of claim 1 , wherein the resin is a silicone resin.
17. The luminescent layer of claim 16 , wherein the ultra-fine particles include at least one of silicon dioxide and aluminum oxide.
18. The luminescent layer of claim 1 , wherein the luminescent layer is formed by a screen-printing process.
19. The luminescent layer of claim 1 , wherein the luminescent layer has a substantial thickness larger than 50 μm.
20. The luminescent layer of claim 19 light-emitting semiconductor device of claim 9, wherein:
the ultra-fine particles include at least one of silicone silicon dioxide and aluminum oxide,
the translucent resin is a silicon silicone resin, and
the luminescent layer has a substantial thickness in the range from equal to or greater than 50 μm to and equal to or less than 1000 μm both inclusive.
21. The luminescent layer of claim 1 light-emitting semiconductor device of claim 9, wherein the absolute specific gravity of the phosphor particles is greater than or equal to 3.0.
22. The luminescent layer of claim 1 , wherein the ultra-fine particles are dispersed within the translucent resin.
23. The light-emitting semiconductor device of claim 9, wherein a thickness of the luminescent layer is equal to or greater than 100 μm and equal to or less than 700 μm.
24. The light-emitting semiconductor device of claim 9, wherein, when viewed in plan, a part of the supporter is exposed from the luminescent layer.
25. The light-emitting semiconductor device of claim 24, wherein the supporter covers a side surface of the luminescent layer.
26. The light-emitting semiconductor device of claim 9, wherein a space is formed between the supporter, the light-emitting device and the luminescent layer.