التفاصيل البيبلوغرافية
| العنوان: |
Semiconductor Light Emitting Diode |
| Document Number: |
20110297955 |
| تاريخ النشر: |
December 8, 2011 |
| Appl. No: |
13/146179 |
| Application Filed: |
February 08, 2010 |
| مستخلص: |
A highly-efficient semiconductor light emitting diode with improved light extraction efficiency comprising at least a substrate having a plurality of crystal planes, a first conductivity-type barrier layer, an active layer serving as a light emitting layer and a second conductivity-type barrier layer stacked on the substrate. The semiconductor light emitting diode comprises a ridge structure configured from one flat surface and at least two inclining surfaces in the in-plane direction. The width (W) of the flat surface of the ridge structure is 2λ (λ: light emission wavelength) or less. The active layer is positioned in the laminating direction so that the shortest length (L) between two points is λ (light emission wavelength) or less, wherewith the first point is the shortest point where the light emitted from the center (C) of the active layer begins total internal reflection at the interface between the inclining surfaces of the ridge structure and air, and the second point is a point where the flat surface begins. |
| Inventors: |
Wang, Xuelun (Ibaraki, JP); Ogura, Mutsuo (Ibaraki, JP) |
| Assignees: |
National Institute of Advanced Industrial Science and Technology (Tokyo, JP) |
| Claim: |
1. A semiconductor light emitting diode comprising at least a substrate having a plurality of crystal planes, a first conductivity-type barrier layer, an active layer serving as a light emitting layer and a second conductivity-type barrier layer stacked on the substrate, wherein the semiconductor light emitting diode comprises a ridge structure configured from one flat surface and at least two inclining surfaces in an in-plane direction, a width (W) of a flat surface of the ridge structure is 2λ (λ: light emission wavelength) or less, and the active layer is positioned in a laminating direction so that a shortest length (L) between two points is λ (light emission wavelength) or less, wherewith a first point is a shortest point where light emitted from a center (C) of the active layer begins total internal reflection at an interface between the inclining surfaces of the ridge structure and air, and second point is a point where the flat surface begins. |
| Claim: |
2. A semiconductor light emitting diode comprising at least a substrate having a plurality of crystal planes, a first conductivity-type barrier layer, an active layer serving as a light emitting layer and a second conductivity-type barrier layer stacked on the substrate, wherein the semiconductor light emitting diode comprises a ridge structure configured from one flat surface and at least two inclining surfaces in an in-plane direction, a width (W) of a flat surface of the ridge structure is 2λ (λ: light emission wavelength) or less, and a film with a refractive index that is smaller than a semiconductor layer of an outermost surface, which comes in contact with air, of the light emitting diode is formed on the surface of the light emitting diode so as to cover the flat surface and at least a part of the inclining surfaces of the ridge structure. |
| Claim: |
3. The light emitting diode according to claim 1, wherein a film with a refractive index that is smaller than a semiconductor layer of an outermost surface, which comes in contact with air, of the light emitting diode is formed on the surface of the light emitting diode so as to cover the flat surface and at least a part of the inclining surfaces of the ridge structure. |
| Claim: |
4. The light emitting diode according to claim 2, wherein the film with a refractive index is a multi-layer film configured from a plurality of films with a different refractive index. |
| Claim: |
5. The light emitting diode according to claim 4, wherein a refractive index of the multi-layer film configured from a plurality of films with a different refractive index gradually becomes smaller from the semiconductor side to the surface side. |
| Claim: |
6. The light emitting diode according to claim 2, wherein the film with a small refractive index is selected from the group consisting of an insulating film, such as a silicon oxide film (SiO2), a silicon nitride film (SiNx), of and aluminum oxide (Al2O3). |
| Claim: |
7. The light emitting diode according to claim 2, wherein the film with a small refractive index is selected from the group consisting of a transparent conductive film, such as ITO, and Of zinc oxide (ZnO). |
| Claim: |
8. The light emitting diode according to claim 4, wherein the multi-layer film is a combination of a silicon nitride film (SiNx) and a silicon oxide film (SiO2). |
| Claim: |
9. The light emitting diode according to claim 4, wherein the multi-layer film is a combination of ITO (indium oxide-tin oxide) and a silicon oxide film (SiO2). |
| Claim: |
10. The light emitting diode according to claim 4, wherein the multi-layer film is a combination of zinc oxide (ZnO) and a silicon oxide film (SiO2). |
| Claim: |
11. The light emitting diode according to claim 1, wherein the flat surface of the ridge structure is a slightly inclined crystal plane that is misorientated approximately several to 10 degrees from an accurate Miller index plane. |
| Claim: |
12. The light emitting diode according to claim 1, wherein the ridge structure is arranged in multiple arrays in the in-plane direction. |
| Claim: |
13. The light emitting diode according to claim 1, wherein the substrate is a substrate that is configured by forming a plurality of crystal planes on a flat substrate based on a combination of lithography and etching process. |
| Claim: |
14. The light emitting diode according to claim 1, wherein the substrate is a selectively-grown substrate formed with a plurality of different crystal planes by disposing a pattern of an insulating film on a flat substrate and subsequent selective epitaxial growth. |
| Claim: |
15. The light emitting diode according to claim 1, wherein the semiconductor is selected from the group consisting of a zincblende structure semiconductor, AlGaAs, and AlGaInP, and wherein the ridge flat surface having a width (W) of 2λ (λ: light emission wavelength) or less is a {001} plane. |
| Claim: |
16. The light emitting diode according to claim 1, wherein the semiconductor is selected from the group consisting of a zincblende structure semiconductor, AlGaAs, and AlGaInP, and wherein the inclining surface of the ridge structure is a {n11} A plane (n=1, 2, 3, 4 and 5). |
| Claim: |
17. The light emitting diode according to claim 1, wherein the semiconductor is selected from the group consisting of a zincblende structure semiconductor, AlGaAs, and AlGaInP, and wherein a {111} A plane is the inclining plane and a {001} plane is the flat surface, and a crystal plane having a higher index than the {111} A plane is provided between the {111} A inclining surface and the {001} flat surface. |
| Claim: |
18. The light emitting diode according to claim 1, wherein the semiconductor is a wurtzite structure semiconductor or GaN, and wherein the ridge flat surface having a width (W) of 2λ (λ: light emission wavelength) or less is a {0001} plane. |
| Current U.S. Class: |
257/76 |
| Current International Class: |
01; 01 |
| رقم الانضمام: |
edspap.20110297955 |
| قاعدة البيانات: |
USPTO Patent Applications |