Nitride semiconductor light emitting element and production thereof

• US 6,984,841 B2
• Filed: 01/30/2002
• Issued: 01/10/2006
• Est. Priority Date: 02/15/2001
• Status: Expired due to Term

• 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: Ito, Shigetoshi, Taneya, Mototaka, Hanaoka, Daisuke, Yuasa, Takayuki, Tsuda, Yuhzoh
• Primary Examiner(s): Jackson, Jerome
• Assistant Examiner(s): FENTY, JESSE A
• Application Number:
  US10/468,061
• Publication Number:
  US 20040041156A1
• Time in Patent Office: 1,441 Days
• Field of Search: 257 12- 15
• US Class Current: 257/12
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• 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 24/05 of an individual bonding area
• CPC Class Codes: H01L 33/007 comprising nitride compounds
• CPC Class Codes: H01L 33/08 with a plurality of light emitting regions, e.g. laterally discontinuous light emitting layer or photoluminescent region integrated within the semiconductor body H01L27/15 takes precedence
• CPC Class Codes: H01L 33/20 with a particular shape, e.g. curved or truncated substrate
• CPC Class Codes: H01S 2304/12 Pendeo epitaxial lateral overgrowth [ELOG], e.g. for growing GaN based blue laser diodes
• CPC Class Codes: H01S 5/0021 Degradation or life time measurements
• CPC Class Codes: H01S 5/0207 Substrates having a special shape
• CPC Class Codes: H01S 5/320225 polar orientation
• CPC Class Codes: H01S 5/34333 with a well layer based on Ga(In)N or Ga(In)P, e.g. blue laser
• CPC Class Codes: H01S 5/405 Two-dimensional arrays

Abstract

The nitride semiconductor light emitting device includes a nitride semiconductor underlayer (102) grown on a surface of a nitride semiconductor substrate or a surface of a nitride semiconductor substrate layer laminated over a base substrate of other than a nitride semiconductor, and a light emitting device structure having a light emitting layer (106) including a quantum well layer or a quantum well layer and a barrier layer in contact with the quantum well layer between an n type layer (103–105) and a p type layer (107–110) over the nitride semiconductor underlayer. It includes a depression (D) not flattened on a surface of the light emitting device structure even after growth of the light emitting device structure.

Claims

1. A nitride semiconductor light emitting device, comprising:

a processed substrate (101a) including at least a groove (G) and at least a hill (H) formed on a surface of a nitride semiconductor;

a nitride semiconductor underlayer (102) grown to cover said groove and said hill of said processed substrate; and

a light emitting device structure having a light emitting layer (106) including a quantum well layer or a quantum well layer and a barrier layer in contact with the quantum well layer between an n type layer (103–

105) and a p type layer (107–

110) over said nitride semiconductor underlayer,

wherein there exists at least a depression (D) not flatten above at least one of said groove and said hill even after growth of said nitride semiconductor underlayer of said light emitting device structure,

and wherein in the case that a first depression is formed above said hill and no depression is formed above said groove, a light emitting portion of said light emitting device structure is formed above a region within the width of said groove and more than 1 μ

m away from the width center of said groove in the width direction or within the width of said hill and more than 2 μ

m away from a side edge of said first depression in the width direction;

or

in the case that a second depression is formed above said groove and no depression is formed above said hill, the light emitting portion of sold light emitting device structure is formed above a region within the width of said hill and more than 1 μ

m away from the center of said hill in the width direction or within the width of said groove and more than 2 μ

m away from a side edge of said second depression in the width direction;

or

in the case that the first depression is formed above said hill and the second depression is formed above said groove in said nitride semiconductor underlayer, the light emitting portion of said light emitting device structure is formed above a region within the width of said hill and more than 2 μ

m away from a side edge of said first and second depressions in the width direction or within the width of said groove and more than 2 μ

m away from a side edge of said first and second depressions in the width direction.

2. The nitride semiconductor light emitting device according to claim 1, wherein said processed substrate is entirely formed of a nitride semiconductor.

3. The nitride semiconductor light emitting device according to claim 1, wherein longitudinal directions of said groove and said hill are substantially parallel to a <

1-100>

direction or a <

11-20>

direction of a crystal of said nitride semiconductor underlayer.

4. The nitride semiconductor light emitting device according to claim 1, wherein there is no said depression above said groove or said hill in the case that said groove or said hill has a width in a range of 4–

30 μ

m.

5. The nitride semiconductor light emitting device according to claim 1, wherein there is said depression above said groove or said hill in the case that said groove or said hill has a width in a range of 7–

100 μ

m.

6. The nitride semiconductor light emitting device according to claim 1, wherein said groove has a depth in a range of 1–

9 μ

m and there is no said depression above said groove.

7. The nitride semiconductor light emitting device according to claim 1, wherein said groove has a depth of more than 1 μ

m, there is a remaining thickness of more than 100 μ

m between the bottom of said groove and the back side of said substrate, and said depression exists above said groove.

8. The nitride semiconductor light emitting device according to claim 1, wherein said nitride semiconductor underlayer is formed of GaN, and said GaN contains at least one kind of impurity selected from a group consisting of Si, O, Cl, S, C, Ge, Zn, Cd, Mg and Be at a dose of more than 1×

10¹⁷/cm³ and less than 5×

10¹⁸/cm³.

9. The nitride semiconductor light emitting device according to claim 1, wherein said nitride semiconductor underlayer is formed of Al_xGa₁₋

xN (0.01≦

x≦

0.15), and said Al_xGa<sub>1−

x</sub>N contains at least one kind of impurity selected from a group consisting of Si, O, Cl, S, C, Ge, Zn, Cd, Mg and Be at a dose of more than 3×

10¹⁷/cm³ and less than 5×

10¹⁸/cm³.

10. The nitride semiconductor light emitting device according to claim 1, wherein said nitride semiconductor underlayer is formed of In_xGa₁₋

xN (0.01≦

x≦

0.15), and said In_xGa<sub>1−

x</sub>N contains at least one kind of impurity selected from a group consisting of Si, O, Cl, S, C, Ge, Zn, Cd, Mg and Be at a dose of more than 1×

10¹⁷/cm³ and less than 4×

10¹⁸/cm³.

11. The nitride semiconductor light emitting device according to claim 1, wherein an electrode is formed on an area including at least two said depressions.

12. The nitride semiconductor light emitting device according to claim 1, wherein a dielectric film is formed on an area including at least said first and second depressions.

13. The nitride semiconductor light emitting device according to claim 1, wherein at least one said depression is included in a bonding area between wire bond and said nitride semiconductor device.

14. The nitride semiconductor light emitting device according to claim 1, wherein said light emitting layer contains at least one kind of element of As, P and Sb.

30. An optical apparatus including the nitride semiconductor light emitting device of claim 1.

15. A nitride semiconductor light emitting device, comprising:

a mask substrate having a growth inhibiting stripe film (201) for suppressing growth of a nitride semiconductor thereon formed on a partial surface area of a nitride semiconductor substrate;

a nitride semiconductor underlayer (102) grown on said mask substrate; and

a light emitting device structure having a light emitting layer (106) including a quantum well layer or a quantum well layer and a barrier layer in contact with the quantum well layer between an n type layer (103–

105) and a p type layer (107–

110) over said nitride semiconductor underlayer,

wherein a depression (D) not flattened is formed above said stripe growth inhibiting film even after growth of said light emitting device structure, and

a light emitting portion of said light emitting device structure is formed above a region within the width of said growth inhibiting film and more than 2 μ

m away from a side edge of said depression in the width direction of said growth inhibiting film.

16. The nitride semiconductor light emitting device according to claim 15, wherein a longitudinal direction of said growth inhibiting stripe film is substantially parallel to a <

1-100>

direction or a <

11-20>

direction of a nitride semiconductor crystal included in said mask substrate.

17. The nitride semiconductor light emitting device according to claim 15, wherein there is a gap between said growth inhibiting film and said depression above said growth inhibiting film.

18. The nitride semiconductor light emitting device according to claim 15, wherein said growth inhibiting film has a width in a range of 7–

100 μ

m.

19. The nitride semiconductor light emitting device according to claim 15, wherein said growth inhibiting film has a thickness in a range of 0.05–

10 μ

m.

20. The nitride semiconductor light emitting device according to claim 15, wherein said growth inhibiting film includes at least one dielectric of SiO₂, SiO, SiN_x and SiON_x, or at least one metal of W and Mo.

21. The nitride semiconductor light emitting device according to claim 15, wherein said nitride semiconductor underlayer contains at least one of Al and In.

22. The nitride semiconductor light emitting device according to claim 15, wherein said nitride semiconductor underlayer is formed of GaN, and said GaN contains at least one kind of impurity selected from a group consisting of Si, O, Cl, S, C, Ge, Zn, Cd, Mg and Be at a dose of more than 1×

10¹⁷/cm³ and less than 5×

10¹⁸/cm³.

23. The nitride semiconductor light emitting device according to claim 15, wherein said nitride semiconductor underlayer is formed of Al_xGa₁₋

xN (0.01≦

x≦

0.15), and said Al_xGa<sub>1−

x</sub>N contains at least one kind of impurity selected from a group consisting of Si, O, Cl, S, C, Ge, Zn, Cd, Mg and Be at a dose of more than 3×

10¹⁷/cm³ and less than 5×

10¹⁸/cm³.

24. The nitride semiconductor light emitting device according to claim 15, wherein said nitride semiconductor underlayer is formed of In_xGa₁₋

xN (0.01≦

x≦

0.15), and said In_xGa<sub>1−

x</sub>N contains at least one kind of impurity selected from a group consisting of Si, O, Cl, S, C, Ge, Zn, Cd, Mg and Be at a dose of more than 1×

10¹⁷/cm³ and less than 4×

10¹⁸/cm³.

25. The nitride semiconductor light emitting device according to claim 15, wherein an electrode is formed on an area including at least two said depressions.

26. The nitride semiconductor light emitting device according to claim 15, wherein a dielectric film is formed on an area including at least two said depressions.

27. The nitride semiconductor light emitting device according to claim 15, wherein at least one said depression is included in a bonding area between wire bond and said nitride semiconductor device.

28. The nitride semiconductor light emitting device according to claim 15, wherein said light emitting layer contains at least one kind of element of As, P and Sb.

29. The nitride semiconductor light emitting device according to claim 15, wherein said mask substrate is formed of a nitride semiconductor.

31. An optical apparatus including the nitride semiconductor light emitting device of claim 15.