Semiconductor light-emitting device
A small-sized semiconductor light-emitting device of high emission directivity and high output is provided. A portion of a light extraction section of a semiconductor light-emitting device including a pn-junction portion is covered with a light-shielding substance of low conductivity. The electrical resistance of the light-shielding substance is 10 6 Ωm or higher, and the substance contains powder of at least one species selected from metals and pigments. The powder of metal contains at least one species selected from among Al, Cu, Ag, Au, Pt, Ti, Ni, Sn, Pb, Mg, Zn, Fe, Co, and Cr. The powder is a plate-like powder having a thickness falling within a range of 0.001-10 μm and a length falling within a range of 0.01-100 μm.
1. A semiconductor light-emitting device comprising a pn-junction portion covered with a light-shielding substance,
wherein the light-shielding substance comprises powder on the surface of which an electrically insulating layer is formed, and the light-shielding substance has an electrical resistance of at least 10 6 Ωm.
2. A semiconductor light-emitting device according to claim 1 , wherein the light-shielding substance comprises at least one species selected from among metals and pigments.
3. A semiconductor light-emitting device according to claim 2 , wherein the metal comprises at least one species selected from among Al, Cu, Ag, Au, Pt, Ti, Ni, Sn, Pb, Mg, Zn, Fe, Co, and Cr.
4. A semiconductor light-emitting device according to claim 2 , wherein the pigment comprises at least one species selected from among organic and inorganic pigments, such as extender pigments, white pigments, black pigments, yellow pigments, brown pigments, red pigments, purple pigments, blue pigments, green pigments, fluorescent pigments, and metallic powder pigments.
5. A semiconductor light-emitting device according to claim 2 , wherein the light-shielding substance comprises powder, and the surface of the powder is covered with a resin having a thickness falling within a range of approximately 0.01-30 μm.
6. A semiconductor light-emitting device according to claim 2 , wherein the particle size of the powder falls within a range of approximately 0.01-100 μm.
7. A semiconductor light-emitting device according to claim 2 , wherein the powder is a plate-like powder having a thickness falling within a range of approximately 0.001-10 μm and a length falling within a range of approximately 0.01-100 μm.
8. A semiconductor light-emitting device according to claim 1 , wherein the light-shielding substance comprises a substance having a total reflectivity of 50% or more in an amount of 50 mass % or more.
9. A semiconductor light-emitting device according to claim 1 , wherein the wavelength of emission of the device falls within the range of approximately 350-1,800 nm.
10. A semiconductor light-emitting device according to claim 1 , wherein the light-shielding substance which covers a portion of the device has a transmittance of 50% or less with respect to the light emitted by the device.
11. A semiconductor light-emitting device according to claim 1 , wherein the surface of a portion of the device which is covered with the light-shielding substance has an irregular portion.
12. A semiconductor light-emitting device according to claim 11 , wherein the depth of the irregular portion fails within a range of approximately 0.1-50 μm.
13. A resin-encapsulated light-emitting device which is produced from a semiconductor light-emitting device as recited in claim 1 .
14. A resin-encapsulated light-emitting device according to claim 13 , wherein a resin used for encapsulation transmits light emitted from a semiconductor light-emitting device, and comprises any single species selected from among epoxy resins, urea resins, and silicone resins.
15. An optical sensor which is produced from a semiconductor light-emitting device as recited in claim 1 , or a resin-encapsulated light-emitting device as recited in claim 13 .
16. An optical communication apparatus or a display apparatus which is produced from a semiconductor light-emitting device as recited in claim 1 , or from a resin-encapsulated light-emitting device as recited in claim 13 .