Light emitting device and method of manufacturing light emitting device
Provided is a light emitting device having a phosphor layer on a surface of a semiconductor light emitting element and achieving an even light distribution color, and a method of manufacturing the same. A method of manufacturing a light emitting device includes arranging a plurality of semiconductor light emitting elements spaced apart from each other on an expandable sheet, spraying a slurry containing a solvent, a thermosetting resin, and phosphor particles, onto an entire surface of the sheet having the arranged semiconductor light emitting elements to form a resin layer, pre-curing the resin layer, disuniting the resin layer formed on the surface of the semiconductor light emitting element from the resin layer formed on the sheet by expanding the sheet, and main curing the resin layer, which steps are performed in this order.
1. A method of manufacturing a light emitting device including a wavelength conversion layer which is formed on a surface of a semiconductor light emitting element and which includes a resin layer containing a wavelength conversion member for converting a wavelength of light emitted from the semiconductor light emitting element, the method comprising:
arranging at least two of the semiconductor light emitting elements apart from each other on an expandable sheet having an adhesive surface;
forming the resin layer, containing the wavelength conversion member, on at least one of the semiconductor light emitting elements and the sheet;
disuniting the resin layer by expanding the sheet, wherein
the arranging, the forming, and the disuniting are performed in this order; and
when forming the resin layer, a slurry containing a solvent, a resin, and particles of the wavelength conversion member, and air are respectively sprayed intermittently with a two-fluid nozzle capable of simultaneously spraying gas and liquid.
2. The method of manufacturing a light emitting device according to claim 1 , wherein
the resin layer is made of a thermosetting resin.
3. The method of manufacturing a light emitting device according to claim 2 , further comprising:
temporarily curing the resin layer formed on at least one of the semiconductor light emitting elements and the sheet by heat, for a predetermined time at a predetermined temperature lower than a curing temperature of the thermosetting resin, after forming the resin layer and before disuniting the resin layer.
4. The method of manufacturing a light emitting device according to claim 1 , wherein
the resin layer further contains an inorganic filler.
5. The method of manufacturing a light emitting device according to claim 1 , wherein
a content of an inorganic material including the wavelength conversion member, or a content of an inorganic material including the wavelength conversion member and the inorganic filler, in the resin layer excluding the solvent is 30% by mass or more and 99% by mass or less.
6. The method of manufacturing a light emitting device according to claim 1 , wherein
a thickest portion of the resin layer is equal to or less than 500 μm in thickness, and a disunion portion of the resin layer provided at a lower end of a side surface of the light emitting device is equal to or less than 200 μm in thickness, and the disunion portion has a thickness less than the thickness of the thickest portion.
7. The method of manufacturing a light emitting device according to claim 5 , wherein
the resin layer has a structure having a plurality of stacked layers each having a different ratio of the inorganic material.
8. The method of manufacturing a light emitting device according to claim 7 , wherein
the ratio of the inorganic material of at least one of the plurality of the stacked layers in the resin layer is equal to or more than 50% by mass.
9. The method of manufacturing a light emitting device according to claim 1 , wherein
when disuniting the resin layer, the resin layer formed on at least one of the semiconductor light emitting elements is disunited from the resin layer formed on the sheet.
10. The method of manufacturing a light emitting device according to claim 2 , further comprising:
after disuniting the resin layer, curing the resin layer formed on at least one of the semiconductor light emitting elements by heat for a predetermined time at a predetermined temperature higher than the curing temperature of the thermosetting resin.
11. The method of manufacturing a light emitting device according to claim 1 , wherein
when forming the resin layer, the resin layer is formed in such a manner that the resin layer formed on the sheet has a smaller thickness than the resin layer formed on the side surface of at least one of the semiconductor light emitting elements.
12. The method of manufacturing a light emitting device according to claim 11 , wherein
when forming the resin layer, after the resin layer is initially formed on the semiconductor light emitting elements and the sheet, the thickness of the resin layer on the sheet is reduced by expanding the sheet in an in-plane direction under the condition that the resin layer is not yet cured.
13. The method of manufacturing a light emitting device according to claim 11 , wherein
when forming the resin layer, during the spraying, the thickness of the resin layer formed on the sheet is made smaller than the resin layer formed on the side surface of the semiconductor light emitting elements by reducing an amount of the slurry sprayed onto the sheet by use of a sheet-blocking mask having an opening to expose the semiconductor light emitting element.
14. The method of manufacturing a light emitting device according to claim 1 , wherein
when disuniting the resin layer, the resin layer is disunited by expanding the sheet in a direction perpendicular to a surface of the sheet.
15. The method of manufacturing a light emitting device according to 1 , wherein
the wavelength conversion layer has a film thickness of 1 μm to 500 μm.