Strained quantum-well structure having ternary-alloy material in both quantum-well layers and barrier layers

• US 20030235224A1
• Filed: 06/19/2002
• Published: 12/25/2003
• Est. Priority Date: 06/19/2002
• Status: Abandoned Application

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Ohlander, Ulf Roald
• Application Number:
  US10/173,853
• Publication Number:
  US 20030235224A1
• Time in Patent Office: Days
• US Class Current: 372/46.01
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: H01S 5/3403 having a strained layer structure in which the strain performs a special function, e.g. general strain effects, strain versus polarisation
• CPC Class Codes: H01S 5/34306 emitting light at a wavelength longer than 1000nm, e.g. InP based 1300 and 1500nm lasers
• CPC Class Codes: H01S 5/3434 with a well layer comprising at least both As and P as V-compounds

Abstract

A layer structure for use in a semiconductor laser is formed using semiconductor ternary-alloy materials comprising two elements categorized in the same column of the periodic table. The two elements are present in both the quantum-well layers and the barrier layers at the same composition ratio. The quantum-well layers and the barrier layers may be oppositely strained to provide strain compensation, yielding a total strain for the layer structure that is substantially zero or low enough to prevent relaxation. The layer structure provides good high-temperature performance, low threshold current, good reliability, and low complexity that facilitates strain compensation.

Claims

1. In a semiconductor laser, a structure comprising:

at least one quantum-well layer of a first semiconductor ternary-alloy material comprising two elements categorized in a same column of the periodic table of the elements; and

a plurality of barrier layers of a second semiconductor ternary-alloy material comprising the two elements,

wherein the two elements are provided at a same composition ratio in both the first and second semiconductor ternary-alloy materials, and

wherein each quantum-well layer is disposed between adjacent barrier layers.

2. The structure of claim 1, wherein the two elements are group-V elements.

3. The structure of claim 2, wherein the two elements are As and P.

4. The structure of claim 3, wherein the at least one quantum-well layer comprises InAs_0.45P_0.55 and wherein the barrier layers comprise GaAs_0.45P_0.55 .

5. The structure of claim 1, wherein the first semiconductor ternary-alloy material includes In and wherein the second semiconductor ternary-alloy material includes Ga.

6. The structure of claim 1, wherein the barrier layers and the at least one quantum-well layer are strained with opposite signs and wherein the structure is strain compensated.

7. The structure of claim 6, wherein the at least one quantum-well layer is compressively strained and wherein a total strain from the at least one quantum-well layer and the barrier layers is substantially zero.

8. The structure of claim 1, wherein the at least one quantum-well layer and the barrier layers are incorporated into a semiconductor laser having a substrate comprising InP, and wherein the structure can provide for light emission at a wavelength of substantially 1.3 μ

m.

9. In a semiconductor laser, a multiple-quantum-well structure, comprising:

a plurality of quantum-well layers of a first semiconductor ternary-alloy material; and

a plurality of barrier layers of a second semiconductor ternary-alloy material,

wherein the first and second semiconductor ternary alloy materials both comprise a first element and a second element, the first and second elements being categorized in a same column of the periodic table of the elements, and

wherein the first and second elements are provided at a same composition ratio in both the first and second semiconductor ternary-alloy materials.

10. The structure of claim 9, wherein the first and second elements are group-V elements.

11. The structure of claim 10, wherein the first and second elements are As and P, respectively.

12. The structure of claim 11, wherein the quantum-well layers further comprise In and wherein the barrier layers further comprise Ga.

13. The structure of claim 11, wherein the quantum-well layers comprise InAs_0.45P_0.55 and wherein the barrier layers comprise GaAs_0.45P_0.55.

14. The structure of claim 9, wherein the barrier layers and the quantum-well layers are strained with opposite signs.

15. The structure of claim 14, wherein the quantum-well layers are compressively strained.

16. The structure of claim 15, wherein the structure is strain compensated.

17. The structure of claim 16, wherein a total strain from the quantum-well layers and the barrier layers is substantially zero.

18. The structure of claim 9, wherein the quantum-well layers and the barrier layers are incorporated into a semiconductor laser having an InP substrate, and wherein the structure can provide for light emission at a wavelength of substantially 1.3 μ

m.

19. The structure of claim 9, further comprising a plurality of spacer layers, wherein each quantum-well layer is disposed between a pair of adjacent barrier layers to form a plurality of three-layer structures and wherein each spacer layer is disposed between a pair of adjacent three-layer structures.

20. A method of fabricating a layer structure of a semiconductor laser, the method comprising:

providing a substrate; and

forming at least one quantum-well layer of a first semiconductor ternary-alloy material and a plurality of barrier layers of a second semiconductor ternary-alloy material on the substrate,

wherein the first and second semiconductor ternary alloy materials both comprise a first element and a second element, the first and second elements being categorized in a same column of the periodic table of the elements, and

wherein the first and second elements are provided at a same composition ratio in both the first and second semiconductor ternary-alloy materials.

21. The method of claim 20, wherein the two elements are group-V elements.

22. The method of claim 21, wherein the two elements are As and P.

23. The method of claim 22, wherein the at least one quantum-well layer comprises InAS_0.45P_0.55 and wherein the barrier layers comprise GaAs_0.45P_0.55.

24. The method of claim 20, wherein the first semiconductor ternary-alloy material includes In and wherein the second semiconductor ternary-alloy material includes Ga.

25. The method of claim 20, wherein the barrier layers and the at least one quantum-well layer are formed with strains of opposite signs and wherein the barrier layers and the quantum-well layer form a structure that is strain compensated.

26. The method of claim 25, wherein the at least one quantum-well layer is compressively strained and wherein a total strain from the at least one quantum-well layer and the barrier layers is substantially zero.

27. The method of claim 20, wherein the substrate comprises InP, and wherein the barrier layers and the at least one quantum-well layer form a structure that can provide for light emission at a wavelength of substantially 1.3 μ

m.