HYBRID LASER DIODE FOR SINGLE MODE OPERATION AND METHOD OF FABRICATING THE SAME

• US 20090154517A1
• Filed: 05/09/2008
• Published: 06/18/2009
• Est. Priority Date: 12/12/2007
• Status: Active Grant

• Current Assignee: Electronics and Telecommunications Research Institute
• Original Assignee: Electronics and Telecommunications Research Institute
• Inventors: KIM, Ki-Soo, KWON, O-Kyun, SONG, Jung-Ho, LEEM, Young-Ahn, KIM, Gyung-Ock
• Granted Patent: US 7,974,326 B2
• Time in Patent Office: Days
• US Class Current: 372/50.110
• CPC Class Codes: H01S 5/0215 Bonding to the substrate
• CPC Class Codes: H01S 5/026 Monolithically integrated components, e.g. waveguides, monitoring photo-detectors, drivers stabilisation of output H01S5/06
• CPC Class Codes: H01S 5/1014 Tapered waveguide, e.g. spotsize converter H01S5/1064 takes precedence
• CPC Class Codes: H01S 5/1032 Coupling to elements comprising an optical axis that is not aligned with the optical axis of the active region
• CPC Class Codes: H01S 5/12 the resonator having a periodic structure, e.g. in distributed feedback [DFB] lasers comprising a photonic bandgap structure H01S5/11; surface-emitting lasers H01S5/18
• CPC Class Codes: H01S 5/32333 based on InGaAsP

Abstract

Provided are a hybrid laser diode for single mode operation, and a method for manufacturing the hybrid laser diode. The hybrid laser diode includes a silicon layer, an active pattern disposed on the silicon layer, and a bonding layer disposed between the silicon layer and the active pattern. Here, the bonding layer includes diffraction patterns constituting a Bragg grating.

Claims

1. A hybrid laser diode comprising:

a silicon layer;

an active pattern disposed on the silicon layer; and

a bonding layer interposed between the silicon layer and the active pattern,

wherein the bonding layer includes diffraction patterns constituting a Bragg grating.

2. The hybrid laser diode of claim 1, wherein the diffraction patterns of the bonding layer are formed to define openings exposing the silicon layer, the openings are formed to have an interval and an arrangement capable of satisfying Bragg'"'"'s condition corresponding to a wavelength of light generated by the hybrid laser diode.

3. The hybrid laser diode of claim 2, wherein the openings are filled with a material having a lower refractive index than the bonding layer.

4. The hybrid laser diode of claim 1, wherein the bonding layer is formed of a material having a lower refractive index than the silicon layer and the active pattern.

5. The hybrid laser diode of claim 4, wherein the bonding layer is a silicon oxide layer.

6. The hybrid laser diode of claim 1, wherein the bonding layer has a thickness ranging from about 10 nm to about 100 nm.

7. The hybrid laser diode of claim 1, wherein the diffraction pattern has a coupling coefficient ranging from about 20 cm⁻

1 to about 100 cm<sup>−

1</sup>, and the coupling coefficient of the diffraction pattern is adjusted by controlling at least one of a thickness of the bonding layer, a refractive index of the bonding layer, and a width of the bonding layer.

8. The hybrid laser diode of claim 1, wherein the bonding layer is extended from the diffraction pattern to cover the silicon layer around the active pattern, and a width of the bonding layer having the diffraction pattern is wider or the same as a width of the diffraction pattern.

9. The hybrid laser diode of claim 1, wherein the silicon layer is used as a slab waveguide, and the active layer is used as a channel waveguide.

10. The hybrid laser diode of claim 1, wherein the silicon layer is used as a channel waveguide, and the active layer is used as a slab waveguide.

11. A hybrid laser diode comprising:

a silicon layer;

a compound semiconductor pattern disposed on the silicon layer; and

a resonator assembly formed between the silicon layer and the compound semiconductor pattern, wherein the resonator assembly is formed of materials having lower refractive indices than the silicon layer and the compound semiconductor pattern.

12. The hybrid laser diode of claim 11, wherein the resonator assembly has a coupling coefficient ranging from about 20 cm⁻

1 to about 100 cm<sup>−

1</sup> such that the hybrid laser diode generate a single mode laser beam.

13. The hybrid laser diode of claim 11, further comprising a bonding layer interposed between the silicon layer and the compound semiconductor pattern to define a plurality of openings exposing the silicon layer, wherein the bonding layer having the plurality of openings is used as the resonator assembly.

14. The hybrid laser diode of claim 13, wherein the openings are formed to have an interval and an arrangement capable of satisfying Bragg'"'"'s condition corresponding to a wavelength of light generated by the hybrid laser diode.

15. The hybrid laser diode of claim 13, wherein the openings are filled with a material having a lower refractive index than the bonding layer such that the openings constitute Bragg gratings providing optical feedback.

16. A method for fabricating a hybrid laser diode, comprising:

preparing a substrate having a silicon layer;

forming a silicon oxide layer on the silicon layer;

attaching a compound semiconductor layer on the substrate by using the silicon oxide layer as a bonding layer; and

forming an active pattern by patterning the compound semiconductor layer, wherein the forming of the silicon oxide layer comprises forming a plurality of openings constituting a Bragg grating, and the openings are patterned such that the Bragg grating has a coupling coefficient for single mode oscillation.

17. The method of claim 16, wherein the openings are filled with a material having a lower refractive index than the silicon oxide layer, and

the forming of the silicon oxide layer comprises patterning the silicon oxide layer such that a coupling coefficient for the single mode oscillation is satisfied by a thickness and a width of the silicon oxide layer.