Nitride-based compound semiconductor light emitting device, structural unit thereof, and fabricating method thereof

• US 20060043387A1
• Filed: 09/01/2005
• Published: 03/02/2006
• Est. Priority Date: 09/02/2004
• Status: Active Grant

• Current Assignee: Sharp Fukuyama Laser Co., Ltd. (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Hata, Toshio
• Granted Patent: US 7,554,124 B2
• Time in Patent Office: Days
• US Class Current: 257/79
• CPC Class Codes: H01L 2224/48463 the connecting portion on the bonding area of the semiconductor or solid-state body being a ball bond
• CPC Class Codes: H01L 33/20 with a particular shape, e.g. curved or truncated substrate
• CPC Class Codes: H01L 33/32 containing nitrogen

Abstract

A nitride-based compound semiconductor light emitting device includes a first conductive substrate, a first ohmic electrode formed on the first conductive substrate, a bonding metal layer formed on the first ohmic electrode, a second ohmic electrode formed on the bonding metal layer, and a nitride-based compound semiconductor layer formed on the second ohmic electrode. The nitride-based compound semiconductor layer includes at least a P-type layer, a light emitting layer and an N-type layer, and has a concave groove portion or a concave-shaped portion.

Claims

1. A nitride-based compound semiconductor light emitting device, comprising:

a first conductive substrate;

a first ohmic electrode formed on the first conductive substrate;

a bonding metal layer formed on the first ohmic electrode;

a second ohmic electrode formed on the bonding metal layer; and

a nitride-based compound semiconductor layer formed on the second ohmic electrode, wherein

the nitride-based compound semiconductor layer includes at least a P-type layer, a light emitting layer and an N-type layer, and has a concave groove portion or a concave-shaped portion.

2. The nitride-based compound semiconductor light emitting device according to claim 1, wherein said first conductive substrate has a concave groove portion or a concave-shaped portion.

3. The nitride-based compound semiconductor light emitting device according to claim 1, wherein said first conductive substrate is a semiconductor of at least one kind of material selected from the group consisting of Si, GaAs, GaP, Ge and InP.

4. The nitride-based compound semiconductor light emitting device according to claim 1, wherein said nitride-based compound semiconductor layer is formed using a second substrate, and the second substrate is an insulative substrate of sapphire, spinel or lithium niobate, or a conductive substrate of silicon carbide, silicon, zinc oxide or gallium arsenide.

5. The nitride-based compound semiconductor light emitting device according to claim 1, wherein said bonding metal layer includes a first bonding metal layer and a second bonding metal layer.

6. The nitride-based compound semiconductor light emitting device according to claim 1, wherein said bonding metal layer includes at least two layers formed of different materials from each other or formed of the same material.

7. A nitride-based compound semiconductor light emitting device structural unit, including a nitride-based compound semiconductor layer having a buffer layer, an N-type layer, a light emitting layer and a P-type layer successively formed on a second substrate, wherein said nitride-based compound semiconductor layer has a concave groove portion.

8. The nitride-based compound semiconductor light emitting device structural unit according to claim 7, wherein said concave groove portion is also formed in said second substrate.

9. The nitride-based compound semiconductor light emitting device structural unit according to claim 7, wherein said second substrate is an insulative substrate of sapphire, spinel or lithium niobate, or a conductive substrate of silicon carbide, silicon, zinc oxide or gallium arsenide.

10. The nitride-based compound semiconductor light emitting device structural unit according to claim 7, wherein a second ohmic electrode is further formed on said nitride-based compound semiconductor layer.

11. A nitride-based compound semiconductor light emitting device, having a first conductive substrate and the nitride-based compound semiconductor light emitting device structural unit recited in claim 7 integrated into one piece via a bonding metal layer such that said nitride-based compound semiconductor layer and said first conductive substrate are adjacent to each other.

12. The nitride-based compound semiconductor light emitting device according to claim 11, wherein said first conductive substrate has a concave groove portion.

13. A fabricating method of a nitride-based compound semiconductor light emitting device, comprising the steps of:

forming a nitride-based compound semiconductor layer on a second substrate;

forming a concave groove portion in the nitride-based compound semiconductor layer;

forming a second ohmic electrode on the nitride-based compound semiconductor layer having the concave groove portion;

forming a second bonding metal layer on the second ohmic electrode;

forming a first ohmic electrode on a first conductive substrate;

forming a first bonding metal layer on the first ohmic electrode;

bonding said first bonding metal layer to said second bonding metal layer;

removing said second substrate to expose a surface of said nitride-based compound semiconductor layer; and

forming a transparent electrode on the exposed surface.

14. The fabricating method of a nitride-based compound semiconductor light emitting device according to claim 13, wherein said step of forming the nitride-based compound semiconductor layer on the second substrate includes the step of stacking at least an N-type layer, a light emitting layer and a P-type layer successively in this order from the second substrate side.

15. The fabricating method of a nitride-based compound semiconductor light emitting device according to claim 13, comprising the step of forming a reflecting layer on said second ohmic electrode between said step of forming the second ohmic electrode and said step of forming the second bonding metal layer, and said step of forming the second bonding metal layer includes the step of forming the second bonding metal layer on the reflecting layer.

16. A fabricating method of a nitride-based compound semiconductor light emitting device, comprising the steps of:

forming a nitride-based compound semiconductor layer on a second substrate;

forming a concave groove portion in the nitride-based compound semiconductor layer;

forming a second ohmic electrode on the nitride-based compound semiconductor layer having the concave groove portion;

forming a second bonding metal layer on the second ohmic electrode;

forming a concave groove portion in a first conductive substrate;

forming a first ohmic electrode on the first conductive substrate having the concave groove portion;

forming a first bonding metal layer on the first ohmic electrode;

bonding said first bonding metal layer to said second bonding metal layer;

removing said second substrate to expose a surface of said nitride-based compound semiconductor layer; and

forming a transparent electrode on the exposed surface.