Semiconductor light emitting device and method for manufacturing same

• US 20030205714A1
• Filed: 04/17/2003
• Published: 11/06/2003
• Est. Priority Date: 03/10/2000
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Idei, Yasuo, Abe, Hirohisa, Konno, Kuniaki, Sugawara, Hideto, Nitta, Koichi
• Granted Patent: US 6,815,725 B2
• Time in Patent Office: Days
• US Class Current: 257/89
• CPC Class Codes: H01L 25/0756 Stacked arrangements of devices
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 33/0093 Wafer bonding; Removal of the growth substrate
• CPC Class Codes: H01L 33/30 containing only elements of Group III and Group V of the Periodic Table
• CPC Class Codes: H01L 33/32 containing nitrogen
• CPC Class Codes: H01L 33/502 Wavelength conversion materials

Abstract

There are provided a semiconductor light emitting device wherein the variation in tone in each device is small and the variation in tone due to deterioration with age is also small, and a method for manufacturing the same. The semiconductor light emitting device includes an active layer for emitting primary light having a first wavelength by current injection, and a light emitting layer excited by the primary light for emitting secondary light having a second wavelength different from said first wavelength, wherein the primary light and the secondary light are mixed to be outputted.

Claims

1. A semiconductor light emitting device comprising:

a semiconductor light emitting element which has an active layer for emitting primary light having a first wavelength by current injection; and

at least one semiconductor laminate which is bonded to said semiconductor light emitting element and which has a light emitting layer, excited by said primary light, for emitting secondary light having a second wavelength different from said first wavelength,

wherein said primary light and said secondary light are mixed to be outputted.

2. A semiconductor light emitting device as set forth in claim 1, wherein said active layer is a In_pGa_qAl_1-p-qN (0≦

p≦

1, 0≦

q≦

1, 0 ≦

p+q≦

1) active layer, and said light emitting layer is an In_bGa_cAl_1-b-cP (0≦

b≦

1, 0≦

c≦

1, 0≦

b+c≦

1) light emitting layer.

3. A semiconductor light emitting device as set forth in claim 2, wherein said active layer is an active layer for emitting blue light, and said light emitting layer is a light emitting layer, excited by the blue light emitted from said active layer, for emitting yellow light.

4. A semiconductor light emitting device as set forth in claim 1, wherein said semiconductor laminate has a first light emitting layer excited by said primary light for emitting said secondary light, and a second light emitting layer, excited by said primary light and said secondary light, for emitting tertiary light having a third wavelength.

5. A semiconductor light emitting device as set forth in claim 4, wherein said active layer is an In_pGa_qAl_1-p-qN (0≦

p≦

1, 0≦

q≦

1, 0≦

p+q≦

1) active layer for emitting blue light, said first light emitting layer is an In_bGa_cAl_1-b-cP (0≦

b≦

1, 0≦

c≦

1, 0≦

b+c≦

1) light emitting layer, excited by said blue light emitted from said active layer, for emitting green light, and

said second light emitting layer is an In_xGa_yAl_1-x-yP (0≦

x≦

1, 0 ≦

y≦

1, 0≦

x+y≦

1) light emitting layer, excited by said blue light and said green light, for emitting red light.

6. A semiconductor light emitting device as set forth in claim 2, wherein said light emitting layer is a light emitting layer of an InAlP/InGaAlP multilayer film.

7. A semiconductor light emitting device as set forth in claim 6, wherein said semiconductor laminate has a structure wherein said light emitting layer is located between an In_dGa_eAl_1-d-eP (0≦

d≦

1, 0≦

e≦

1, 0≦

d+e≦

1) cladding layer and a GaAs substrate, and a surface of said semiconductor laminate on the side of said In_dGa_eAl_1-d-eP cladding layer is bonded to a surface of said semiconductor light emitting element opposite to a light emitting surface.

8. A semiconductor light emitting device as set forth in claim 6, wherein said semiconductor laminate has a structure wherein said light emitting layer is located between an In_dGa_eAl_1-d-eP (0≦

d≦

1, 0≦

e≦

1, 0≦

d+e≦

1) cladding layer and a protection layer, and a surface of said semiconductor laminate on the side of said In_dGa_eAl_1-d-eP cladding layer is bonded to said semiconductor light emitting element.

9. A semiconductor light emitting device as set forth in claim 6, wherein said semiconductor laminate has a structure wherein said light emitting layer is located between an In_dGa_eAl_1-d-eP (0≦

d≦

1, 0≦

e≦

1, 0≦

d+e≦

1) cladding layer and a substrate capable of transmitting said secondary light emitted from said light emitting layer, and a surface of said semiconductor laminate on the side of said In_dGa_eAl_1-d-eP cladding layer is bonded to said semiconductor light emitting element.

10. A semiconductor light emitting device as set forth in claim 2, wherein said active layer is an active layer having a GaN/InGaN multi-quantum well structure.

11. A semiconductor light emitting device as set forth in claim 2, wherein said semiconductor light emitting element comprises:

a substrate having first and second surfaces;

a buffer layer formed on said first surface of said substrate;

a first conductive type In_rGa_sAl_1-r-sN (0≦

r≦

1, 0≦

s≦

1, 0≦

r+s≦

1) cladding layer formed on said buffer layer;

said active layer formed on said first conductive type In_rGa_sAl_1-r-sN cladding layer; and

a second conductive type In_tGa_uAl_1-t-uN (0≦

t≦

1, 0≦

u≦

1, 0≦

t+u≦

1) cladding layer formed on said active layer.

12. A semiconductor light emitting device as set forth in claim 2, wherein said semiconductor light emitting element comprises:

a sapphire substrate having first and second surfaces;

a buffer layer formed on said first surface of said sapphire substrate;

an n-type In_rGa_sAl_1-r-sN (0≦

r≦

1, 0≦

s≦

1, 0≦

r+s≦

1) cladding layer formed on said buffer layer;

said active layer formed on said n-type In_rGa_sAl_1-r-sN cladding layer;

a p-type In_tGa_uAl_1-t-uN (0≦

t≦

1, 0≦

u≦

1, 0≦

t+u≦

1) cladding layer formed on said active layer;

a p-type In_vGa_wAl_1-v-wN (0≦

v≦

1, 0≦

w≦

1, 0≦

v+w≦

1) contact layer formed on said p-type In_tGa_uAl_1-t-uN cladding layer;

a p-side electrode formed on said p-type In_vGa_wAl_1-v-wN contact layer; and

an n-side electrode formed on said n-type In_rGa_sAl_1-r-sN (0≦

r≦

1, 0≦

s≦

1, 0≦

r+s≦

1) cladding layer exposed by etching.

13. A semiconductor light emitting device as set forth in claim 2, wherein said semiconductor light emitting element comprises:

an n-type semiconductor substrate having first and second surfaces;

a buffer layer formed on said first surface of said substrate;

an n-type In_rGa_sAl_1-r-s N (0≦

r≦

1, 0≦

s≦

1, 0≦

r+s≦

1) cladding layer formed on said buffer layer;

said active layer formed on said n-type In_rGa_sAl_1-r-sN cladding layer;

a p-type In_tGa_uAl_1-t-uN (0≦

t≦

1, 0≦

u≦

1, 0≦

t+u≦

1) cladding layer formed on said active layer;

a p-type In_vGa_wAl_1-v-wN (0≦

v≦

1, 0 ≦

w≦

1, 0≦

v+w≦

1) contact layer formed on said p-type In_tGa_uAl_1-t-uN cladding layer; and

a p-side transparent electrode formed on said p-type In_vGa_wAl_1-v-wN contact layer,

light being emitted from the side of said p-type In_vGa_wAl_1-v-wN contact layer,

and wherein said semiconductor laminate comprises;

an n-type GaAs substrate having first and second surfaces;

said light emitting layer of an n-type InAlP/InGaAlP multilayer film formed on said first surface of said n-type GaAs substrate;

an n-type In_dGa_eAl_1-d-eP (0≦

d≦

1, 0≦

e≦

1, 0≦

d+e≦

1) cladding layer formed on said light emitting layer; and

an n-side electrode formed on said second surface of said n-type GaAs substrate,

said n-type In_dGa_eAl_1-d-eP cladding layer of said semiconductor laminate being bonded to said second surface of said n-type semiconductor substrate of said semiconductor light emitting element.

14. A semiconductor light emitting device as set forth in claim 13, wherein said n-type semiconductor substrate is made of a material selected from the group consisting of n-type GaN, n-type SiC and n-type Si.

15. A semiconductor light emitting device as set forth in claim 2, wherein said semiconductor light emitting element comprises:

a substrate having first and second surfaces;

a buffer layer formed on said first surface of said substrate;

a first conductive type In_rGa_sAl_1-r-sN (0≦

r≦

1, 0≦

s≦

1, 0≦

r+s≦

1) cladding layer formed on said buffer layer;

said active layer formed on said first conductive type In_rGa_sAl_1-r-sN cladding layer;

a second conductive type In_tGa_uAl_1-t-uN (0≦

t≦

1, 0≦

u≦

1, 0≦

t+u≦

1) cladding layer formed on said active layer; and

a second conductive type In_vGa_wAl_1-v-wN (0≦

v≦

1, 0≦

w≦

1, 0≦

v+w≦

1) contact layer formed on said In_tGa_uAl_1-t-uN cladding layer;

wherein light is emitted from the side of said second conductive type In_vGa_wAl_1-v-wN contact layer,

said semiconductor laminate being bonded on said second surface of said substrate.

16. A semiconductor light emitting device as set forth in claim 2, wherein said semiconductor light emitting element comprises:

a substrate having first and second surfaces;

a buffer layer formed on said first surface of said substrate;

a first conductive type In_rGa_sAl_1-r-sN (0≦

r≦

1, 0≦

s≦

1, 0≦

r+s≦

1) cladding layer formed on said buffer layer;

said active layer formed on said first conductive type In_rGa_sAl_1-r-sN cladding layer;

a second conductive type In_tGa_uAl_1-t-uN (0≦

t≦

1, 0≦

u≦

1, 0≦

t+u≦

1) cladding layer formed on said active layer; and

a second conductive type In_vGa_wAl_1-v-wN (0≦

v≦

1, 0≦

w≦

1, 0≦

v+w≦

1) contact layer formed on said In_tGa_uAl_1-t-uN cladding layer;

wherein light is emitted from said second surface of said substrate,

said semiconductor laminate being bonded on said second surface of said substrate.

24. A semiconductor light emitting device as set forth in claim 2, wherein said semiconductor laminate has a structure wherein said light emitting layer is located between an In_dGa_eAl_1-d-eP (0≦

d≦

1, 0≦

e≦

1, 0≦

d+e≦

1) cladding layer and an In_fGa_hAl_1-f-hP (0≦

f≦

1, 0≦

h≦

1, 0≦

f+h≦

1) cladding layer, and said semiconductor laminate on the side of said In_fGa_hAl_1-f-h P cladding layer is bonded to a portion of said semiconductor light emitting element.

25. A semiconductor light emitting device as set forth in claim 2, wherein said semiconductor light emitting element comprises:

an n-type semiconductor substrate having first and second surfaces;

a buffer layer formed on said first surface of said substrate;

an n-type In_rGa_sAl_1-r-sN (0≦

r≦

1, 0≦

s≦

1, 0≦

r+s≦

1) cladding layer formed on said buffer layer;

said active layer formed on said n-type In_rGa_sAl_1-r-sN cladding layer;

a p-type In_tGa_uAl_1-t-uN (0≦

t≦

1, 0≦

u≦

1, 0≦

t+u≦

1) cladding layer formed on said active layer;

a p-type In_vGa_wAl_1-v-wN (0≦

v≦

1, 0≦

w≦

1, 0≦

v+w≦

1) contact layer formed on said p-type In_tGa_uAl_1-t-uN cladding layer;

a p-side transparent electrode formed on said p-type In_vGa_wAl_1-v-wN contact layer; and

an n-side electrode formed on said second surface of said n-type semiconductor substrate.

26. A semiconductor light emitting device as set forth in claim 2, wherein said semiconductor light emitting element comprises:

a substrate having first and second surface;

a buffer layer formed on said first surface of said n-type semiconductor substrate;

a first conductive type In_rGa_sAl_1-r-sN (0≦

r≦

1, 0≦

s≦

1, 0≦

r+s≦

1) cladding layer formed on said buffer layer;

said active layer formed on said first conductive type In_rGa_sAl_1-r-sN cladding layer;

a second conductive type In_tGa_uAl_1-t-uN (0≦

t≦

1, 0≦

u≦

1, 0≦

t+u≦

1) cladding layer formed on said active layer; and

a second conductive type In_vGa_wAl_1-v-wN (0≦

v≦

1, 0≦

w≦

1, 0≦

v+w≦

1) contact layer formed on said In_tGa_u Al_1-t-uN cladding layer;

wherein light is emitted from the side of said second conductive type In_vGa_wAl_1-v-wN contact layer, and

wherein said semiconductor laminate is bonded on said second conductive type In_vGa_wAl_1-v-wN contact layer.

17. A semiconductor light emitting device comprising:

a GaAs substrate;

an In_bGa_cAl_1-b-cP (0≦

b≦

1, 0≦

c≦

1, 0≦

b+c≦

1) light emitting layer which is formed on said GaAs substrate and which is excited by primary light having a first wavelength for emitting secondary light having a second wavelength;

a buffer layer formed on said In_bGa_cAl_1-b-cP light emitting layer; and

a Zn_jCd_1-jSe (0≦

j≦

1) active layer which is formed on said buffer layer and which emits said primary light having the first wavelength by current injection;

wherein said primary light and said secondary light are mixed to be outputted.

18. A method for manufacturing a semiconductor light emitting device, said method comprising:

a semiconductor light emitting element forming on a first substrate step including a step of forming a semiconductor layers, which has an active layer for emitting primary light having a first wavelength by current injection;

a semiconductor laminate forming step including a step of forming on a second substrate a semiconductor layer, which includes a light emitting layer excited by said primary light for emitting secondary light having a second wavelength different from said first wavelength; and

a bonding step including a step of integrally bonding said semiconductor light emitting element to said semiconductor laminate.

19. A method for manufacturing a semiconductor light emitting device as set forth in claim 18, wherein said active layer is an In_pGa_qAl_1-p-qN (0≦

p≦

1, 0≦

q≦

1, 0≦

p+q≦

1) active layer, and said light emitting layer is an In_bGa_cAl_1-b-cP (0≦

b≦

1, 0≦

c≦

=1, 0≦

b+c≦

1) light emitting layer.

20. A method for manufacturing a semiconductor light emitting device as set forth in claim 19, wherein said semiconductor light emitting element forming step comprises the steps of:

forming a buffer layer on said first substrate;

forming a first conductive type In_rGa_sAl_1-r-sN (0≦

r≦

1, 0≦

s≦

1, 0≦

r+s≦

1) cladding layer on said buffer layer;

forming said active layer on said first conductive type In_rGa_sAl_1-r-sN (0≦

r≦

1, 0≦

s≦

1, 0≦

r+s≦

1) cladding layer; and

forming a second conductive type In_tGa_uAl_1-t-uN (0≦

t≦

1, 0≦

u≦

1, 0≦

t+u≦

1) cladding layer on said active layer,

said semiconductor laminate forming step comprising the steps of forming said light emitting layer on said second substrate, and forming an In_dGa_eAl_1-d-eP (0≦

d≦

1, 0≦

e≦

1, 0≦

d+e≦

1) cladding layer on said light emitting layer,

said bonding step comprising a step of integrally bonding said semiconductor light emitting element to said In_dGa_eAl_1-d-e p cladding layer of said semiconductor laminate.

21. A method for manufacturing a semiconductor light emitting device as set forth in claim 20, wherein said light emitting layer is a light emitting layer of an InAlP/InGaAlP multilayer film, and which further comprises, after said bonding step, a second substrate removing step including a step of removing said second substrate to expose said light emitting layer, and a protection layer forming step including a step of forming a protection layer on said light emitting layer exposed by said second substrate removing step.

22. A method for manufacturing a semiconductor light emitting device as set forth in claim 20, wherein said light emitting layer is a light emitting layer of an InAlP/InGaAlP multilayer film, and which further comprises, after said bonding step, a second substrate removing step including a step of removing said second substrate to expose said light emitting layer, and a third substrate bonding step including a step of a bonding third substrate, which has the property of transmitting said primary light emitted from said active layer and said secondary light emitted from said light emitting layer, to said light emitting layer exposed in said second substrate removing step.

27. A method for manufacturing a semiconductor light emitting device as set forth in claim 20, wherein said semiconductor laminate forming step comprises the steps of:

forming a In_dGa_eAl_1-d-eP (0≦

d≦

1, 0≦

e≦

1, 0≦

d+e≦

1) cladding layer on a GaAs substrate serving as said second substrate;

forming said light emitting layer on said In_dGa_eAl_1-d-e p cladding layer; and

forming a In_fGa_hAl_1-f-hP (0≦

f≦

1, 0≦

h≦

1, 0≦

f+h≦

1) cladding layer on said light emitting layer,

said method further comprising, after said bonding step, a GaAs substrate removing step of removing said GaAs substrate to expose said In_dGa_eAl_1-d-e P cladding layer.

23. A method for manufacturing a semiconductor light emitting device, said method comprising the steps of:

forming on a GaAs substrate an In_bGa_cAl_1-b-cP (0≦

b≦

1, 0≦

c≦

1, 0≦

b+c≦

1) light emitting layer, which is excited by blue light for emitting yellow light;

forming a buffer layer on said In_bGa_cAl_1-b-cP light emitting layer; and

forming on said buffer layer a Zn_jCd_1-jSe (0≦

j≦

1) active layer, which emits said blue light by current injection.

28. A semiconductor light emitting device comprising:

a substrate;

a buffer layer formed on said substrate;

a first conductive type In_rGa_sAl_1-r-sN (0≦

r≦

1, 0≦

s≦

1, 0≦

r+s≦

1) cladding layer formed on said buffer layer,

an In_pGa_qAl_1-p-qN (0≦

p≦

1, 0≦

q≦

1, 0≦

p+q≦

1) active layer formed on said first conductive type In_rGa_sAl_1-r-sN cladding layer and provided with an ion implantation region into which ions selected from the group consisting of fluorine, oxygen, nitrogen, carbon and sulfur have been injected, regions other than said ion implantation region emitting primary light having a first wavelength, and said ion implantation region emitting secondary light having a second wavelength different from said first wavelength; and

a second conductive type In_tGa_uAl_1-t-uN (0≦

t≦

1, 0≦

u≦

1, 0≦

t+u≦

1) cladding layer formed on said active layer.

29. A semiconductor light emitting device comprising:

a semiconductor light emitting element which has an active layer for emitting primary light having a first wavelength by current injection;

reflector for reflecting said primary light emitted from said semiconductor light emitting element; and

fluorescent material which is applied on part of said reflector and which is excited by said primary light for emitting secondary light having a second wavelength different form said first wavelength.