Semiconductor light emitting diode

• US 5,656,829 A
• Filed: 07/05/1995
• Issued: 08/12/1997
• Est. Priority Date: 08/30/1994
• Status: Expired due to Term

• Current Assignee: Showa Denko KK
• Original Assignee: Showa Denko KK
• Inventors: Hosokawa, Yasuo, Nakamura, Sigemasa, Saito, Yutaka, Sakaguchi, Yasuyuki
• Primary Examiner(s): Fahmy, Wael
• Assistant Examiner(s): Abraham, Fetsum
• Application Number:
  US08/498,785
• Time in Patent Office: 769 Days
• Field of Search: 257/21, 257/112, 257/76, 257/82, 257/85, 257/89-97, 257/184-189
• US Class Current: 257/94
• CPC Class Codes: H01L 33/02 characterised by the semiconductor bodies
• CPC Class Codes: H01L 33/14 with a carrier transport control structure, e.g. highly-doped semiconductor layer or current-blocking structure
• CPC Class Codes: H01L 33/30 containing only elements of Group III and Group V of the Periodic Table

Abstract

A semiconductor light emitting diode includes a compound semiconductor substrate and a double-hetero structure of (Al_x Ga_1-x)_y In_1-y P (0≦x≦1, 0<y<1) as an active layer, and an upper clad layer of the double-hetero structure has a larger band gap energy (Eg) than the band gap energy of the active layer and has a thickness of 3-50 μm.

Claims

1. A semiconductor light emitting diode comprising a compound semiconductor substrate and a double-hetero structure of (Al_x Ga_1-x)_y In_1-y P (0≦

x≦

1, 0<

y<

1) as an active layer sandwiched between upper and lower clad layers, the upper clad layer having a larger band gap energy than the band yap energy of the active layer and having a thickness of 5-10 μ

m.

2. A semiconductor light emitting diode according to claim 1, wherein the band gap energy of the upper clad layer is at least 0.1 eV larger than the band gap energy of the active layer.

3. A semiconductor light emitting diode according to claim 2, wherein the double-hetero structure consists of AlGaInP.

4. A semiconductor light emitting diode according to claim 2, wherein the double-hetero structure consists of AlGaInP and GaInP.

5. A semiconductor light emitting diode according to claim 2, wherein the double-hetero structure consists of AlInP and AlGaInP.

6. A semiconductor light emitting diode according to claim 1, wherein the double-hetero structure consists of AlGaInP.

7. A semiconductor light emitting diode according to claim 1, wherein the double-hetero structure consists of AlGaInP and GaInP.

8. A semiconductor light emitting diode according to claim 1, wherein the double-hetero structure consists of AlInP and AlGaInP.

9. A semiconductor light emitting diode comprising a compound semiconductor substrate and a double-hetero structure of (Al_x Ga_1-x)_y In_1-y P (0≦

x≦

1.0<

y<

1) as an active layer sandwiched between upper and lower clad layers, the band gap energy of the upper clad layer gradually decreasing with increasing distance from a light emitting side of the active layer, wherein the band gap energy of the upper clad layer is at least 0.2 eV larger than that of the active layer at a distance 0.5 μ

m from its interface with the active layer.

10. A semiconductor light emitting diode according to claim 9, wherein the double-hetero structure consists of AlGaInP.

11. A semiconductor light emitting diode according to claim 9, wherein the double-hetero structure consists of AlGaInP and GaInP.

12. A semiconductor light emitting diode according to claim 9, wherein the double-hetero structure consists of AlInP and AlGaInP.

13. A semiconductor light emitting diode according to claim 9, wherein the upper clad layer has a thickness of 5-10 μ

m.

14. A semiconductor light emitting diode comprising compound semiconductor substrate and a double-hetero structure of (Al_x Ga_1-x)_y In_1-y P (0≦

x≦

1.0<

y<

1) as an active layer sandwiched between upper and lower clad layers, the band gap energy of the upper clad layer gradually decreasing with increasing distance from a light emitting side of the active layer, wherein the upper clad layer has a thickness of 5-10 μ

m.

15. A semiconductor light emitting diode according to claim 14, wherein the double-hetero structure consists of AlGaInP.

16. A semiconductor light emitting diode according to claim 14, wherein the double-hetero structure consists of AlGaInP and GaInP.

17. A semiconductor light emitting diode according to claim 14, wherein the double-hetero structure consists of AlInP and AlGaInP.

18. A semiconductor light emitting diode comprising compound semiconductor substrate and a double-hetero structure of (Al_x Ga_1-x)_y In_1-y P (0≦

x≦

1.0<

y<

1) as an active layer sandwiched between upper and lower clad layers, carrier concentration of the upper clad layer gradually increasing with increasing distance from a light emitting side of the active layer, wherein the upper clad layer has a thickness of 5-10 μ

m.

19. A semiconductor light emitting diode according to claim 18, wherein the carrier concentration of the upper clad layer is (1-10)×

10¹⁶ cm^-3 at its interface with the active layer and (1-10)×

10¹⁷ cm^-3 at the light emitting side.

20. A semiconductor light emitting diode according to claim 19, wherein the double-hetero structure consists of AlGaInP.

21. A semiconductor light emitting diode according to claim 19, wherein the double-hetero structure consists of AlGaInP and GaInP.

22. A semiconductor light emitting diode according to claim 19, wherein the double-hetero structure consists of AlInP and AlGaInP.

23. A semiconductor light emitting diode according to claim 18, wherein the double-hetero structure consists of AlGaInP.

24. A semiconductor light emitting diode according to claim 18, wherein the double-hetero structure consists of AlGaInP and GaInP.

25. A semiconductor light emitting diode according to claim 18, wherein the double-hetero structure consists of AlInP and AlGaInP.