Light emitting diode element
View Patent ↗An object of the present invention is to provide a GaN-based light emitting diode element having a great emission efficiency and suitable for an excitation light source for a white LED. The GaN-based light emitting diode element includes an n-type conductive m-plane GaN substrate, a light emitting diode structure which is formed of a GaN-based semiconductor, on a front face of the m-plane GaN substrate, and an n-side ohmic electrode formed on a rear face of the m-plane GaN substrate, wherein a forward voltage is 4.0 V or less when a forward current applied to the light emitting diode element is 20 mA.
1. A semiconductor light emitting element comprising:
an n-type conductive m-plane GaN substrate;
a light emitting structure which is formed of a GaN-based semiconductor, on a front face of the m-plane GaN substrate; and
an n-side ohmic electrode formed on a rear face, said rear face polished with an acidic CMP slurry, of the m-plane GaN substrate,
wherein a forward voltage is 4.0 V or less when a forward current applied to the element is 20 mA.
2. A semiconductor light emitting element comprising:
an n-type conductive m-plane GaN substrate;
a light emitting structure which is formed of a GaN-based semiconductor, on a front face of the m-plane GaN substrate; and
an n-side ohmic electrode formed on a rear face, said rear face polished with an acidic CMP slurry, of the m-plane GaN substrate,
wherein a forward voltage is 4.5 V or less when a forward current applied to the element is 60 mA.
3. A semiconductor light emitting element comprising:
an n-type conductive m-plane GaN substrate;
a light emitting structure which is formed of a GaN-based semiconductor, on a front face of the m-plane GaN substrate; and
an n-side ohmic electrode formed on a rear face, said rear face polished with an acidic CMP slurry, of the m-plane GaN substrate,
wherein a forward voltage is 5.0 V or less when a forward current applied to the element is 120 mA.
4. A semiconductor light emitting element comprising:
an n-type conductive m-plane GaN substrate;
a light emitting structure which is formed of a GaN-based semiconductor, on a front face of the m-plane GaN substrate; and
an n-side ohmic electrode formed on a rear face, said rear face polished with an acidic CMP slurry, of the m-plane GaN substrate,
wherein a forward voltage is 5.5 V or less when a forward current applied to the element is 200 mA.
5. A semiconductor light emitting element comprising:
an n-type conductive m-plane GaN substrate;
a light emitting structure which is formed of a GaN-based semiconductor, on a front face of the m-plane GaN substrate; and
an n-side ohmic electrode formed on a rear face, said rear face polished with an acidic CMP slurry, of the m-plane GaN substrate,
wherein a forward voltage is 6.0 V or less when a forward current applied to the element is 350 mA.
6. The semiconductor light emitting element according to claim 1 ,
wherein the light emitting structure comprises an active layer formed of a GaN-based semiconductor, an n-type GaN-based semiconductor layer disposed between the active layer and the m-plane GaN substrate, and a p-type GaN-based semiconductor layer which sandwiches the active layer with the n-type GaN based semiconductor layer.
7. The semiconductor light emitting element according to claim 1 ,
wherein the semiconductor light emitting element is a light emitting diode element.
8. The semiconductor light emitting element according to claim 1 , wherein an area of the rear face of the m-plane GaN substrate is 0.0012 cm 2 or more.
9. The semiconductor light emitting element according to claim 8 , wherein an area of the n-side ohmic electrode is 0.0012 cm 2 or more, and equal to or less than the area of the rear face of the m-plane GaN substrate.
10. The semiconductor light emitting element according to claim 2 ,
wherein the light emitting structure comprises an active layer formed of a GaN-based semiconductor, an n-type GaN-based semiconductor layer disposed between the active layer and the m-plane GaN substrate, and a p-type GaN-based semiconductor layer which sandwiches the active layer with the n-type GaN based semiconductor layer.
11. The semiconductor light emitting element according to claim 2 ,
wherein the semiconductor light emitting element is a light emitting diode element.
12. The semiconductor light emitting element according to claim 2 , wherein an area of the rear face of the m-plane GaN substrate is 0.0012 cm2 or more.
13. The semiconductor light emitting element according to claim 3 ,
wherein the light emitting structure comprises an active layer formed of a GaN-based semiconductor, an n-type GaN-based semiconductor layer disposed between the active layer and the m-plane GaN substrate, and a p-type GaN-based semiconductor layer which sandwiches the active layer with the n-type GaN based semiconductor layer.
14. The semiconductor light emitting element according to claim 3 ,
wherein the semiconductor light emitting element is a light emitting diode element.
15. The semiconductor light emitting element according to claim 3 , wherein an area of the rear face of the m-plane GaN substrate is 0.0012 cm2 or more.
16. The semiconductor light emitting element according to claim 4 ,
wherein the light emitting structure comprises an active layer formed of a GaN-based semiconductor, an n-type GaN-based semiconductor layer disposed between the active layer and the m-plane GaN substrate, and a p-type GaN-based semiconductor layer which sandwiches the active layer with the n-type GaN based semiconductor layer.
17. The semiconductor light emitting element according to claim 4 ,
wherein the semiconductor light emitting element is a light emitting diode element.
18. The semiconductor light emitting element according to claim 4 , wherein an area of the rear face of the m-plane GaN substrate is 0.0012 cm2 or more.
19. The semiconductor light emitting element according to claim 5 ,
wherein the light emitting structure comprises an active layer formed of a GaN-based semiconductor, an n-type GaN-based semiconductor layer disposed between the active layer and the m-plane GaN substrate, and a p-type GaN-based semiconductor layer which sandwiches the active layer with the n-type GaN based semiconductor layer.
20. The semiconductor light emitting element according to claim 5 ,
wherein the semiconductor light emitting element is a light emitting diode element.
21. The semiconductor light emitting element according to claim 5 , wherein an area of the rear face of the m-plane GaN substrate is 0.0012 cm2 or more.
22. The semiconductor light emitting element according to claim 1 , wherein the n-side ohmic electrode has a layered structure comprising a first portion which contacts the substrate formed of at least one metal selected from the group consisting of Ti, Cr, V, W, or ITO, and a second portion which is formed of at least one metal selected from the group consisting of Au, Cu or Ag.