Optoelectronic device and laser diode

• US 6,327,413 B1
• Filed: 01/27/1999
• Issued: 12/04/2001
• Est. Priority Date: 02/02/1998
• Status: Expired due to Fees

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Kinoshita, Junichi
• Primary Examiner(s): Healy, Brian
• Application Number:
  US09/238,493
• Time in Patent Office: 1,042 Days
• Field of Search: 385/129-132, 385/31, 385/37, 385/14, 372/45, 372/46
• US Class Current: 385/129
• CPC Class Codes: H01S 5/0202 Cleaving
• CPC Class Codes: H01S 5/04253 having specific optical properties, e.g. transparent electrodes
• 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 5/1228 DFB lasers with a complex coupled grating, e.g. gain or loss coupling
• CPC Class Codes: H01S 5/1231 Grating growth or overgrowth details
• CPC Class Codes: H01S 5/2275 mesa created by etching

Abstract

Both an electric energy applying mechanism and an optical waveguide mechanism can be provided to an ITO layer (transparent electrode) by constituting an optical waveguide so as that the guided mode profile spread into the ITO layer. Also a bonding pad is provided to supply a power and apply an electric field onto the ITO layer. Accordingly, a device structure can be simplified and thus improvement in yield of the optoelectronic device having an optical waveguide and improvement in parameters of the optoelectronic device can be achieved.

Claims

1. An optoelectronic device comprising:

an optical waveguide structure having at least one optical waveguide;

wherein the optical waveguide structure is formed of transparent electrode, and the transparent electrode is formed directly on an optical waveguide structure having a diffraction grating, and has partly a function of an optical waveguide.

9. An optoelectronic device as claimed in claim 1, wherein refractive index of the transparent electrode is set smaller than an underlying optical waveguide.

12. An optoelectronic device as claimed in claim 1, further comprising dielectric substance or semiconductor which has refractive index, optical loss, or gain being different from the transparent electrode, under the transparent electrode.

2. An optoelectronic device comprising:

an optical waveguide structure having at least one optical waveguide;

wherein the optical waveguide structure is formed of transparent electrode, and the transparent electrode has a distribution of refractive index, waveguide loss, or conductivity therein.

3. An optoelectronic device as claimed in claim 2, wherein the distribution of refractive index, waveguide loss, or conductivity in the transparent electrode is implemented by a multi-layered structure in which each layer has different refractive index, waveguide loss, or conductivity.

4. An optoelectronic device as claimed in claim 2, wherein the distribution of refractive index, waveguide loss, or conductivity in the transparent electrode has periodicity along a waveguide direction of the optical waveguide.

5. An optoelectronic device as claimed in claim 4, wherein the transparent electrode has a single layer structure, or a multi-layered structure in which each layer has different refractive index, waveguide loss, or conductivity, and

the distribution of refractive index, waveguide loss, or conductivity is implemented by changing shapes of respective layers including-their thickness along an axial direction.

8. An optoelectronic device as claimed in claim 2, wherein the distribution of refractive index, waveguide loss, or conductivity in the transparent electrode or periodicity of the diffraction grating is set to produce Bragg scattering of second order or more relative to a waveguide light.

21. An optoelectronic device as claimed in claim 8, wherein an area of the transparent electrode except for a window area from which an optical output is emitted is covered with an opaque electrode.

22. An optoelectronic device as claimed in claim 2, wherein change in optical properties is controlled to give a phase shift effect to the periodical optical structure.

6. An optoelectronic device comprising:

an optical waveguide structure having at least one optical waveguide;

wherein the optical waveguide structure is formed of transparent electrode having a distribution of refractive index, and the distribution of refractive index in the transparent electrode is set larger in a center axis area of the optical waveguide in section than other areas of the optical waveguide.

7. An optoelectronic device comprising:

an optical waveguide structure having at least one optical waveguide;

wherein the optical waveguide structure is formed of transparent electrode, and a transverse sectional shape of the transparent electrode is a semi-circle or a semiellipse.

10. An optoelectronic device as claimed in 1, wherein the transparent electrode is isolated electrically by insulating dielectric substance which has refractive index being substantially identical to the transparent electrode.

11. An optoelectronic device as claimed in claim 10, further comprising a mechanism for driving independently an optoelectronic device formed under a plurality of transparent electrode which are separated electrically by the insulating dielectric substance.

13. An optoelectronic device comprising:

an optical waveguide structure having at least one optical waveguide formed of transparent electrode; and

dielectric substance or semiconductor which has refractive index, optical loss, or gain being different from the transparent electrode, under the transparent electrode, and the dielectric substance or the semiconductor are aligned periodically along a direction of the optical waveguide.

14. An optoelectronic device comprising:

an optical waveguide structure having at least one optical waveguide;

wherein the optical waveguide structure is formed of transparent electrode, and the transparent electrodes are formed of ITO (Indium Tin Oxide).

15. An optoelectronic device as claimed in claim 14, wherein refractive index of the ITO is controlled by an amount of oxygen contained in the ITO.

16. An optoelectronic device as claimed in claim 14, wherein conductivity and insulating characteristic of the ITO is controlled by composition of tin contained in the ITO.

17. An optoelectronic device comprising:

an optical waveguide structure having at least one optical waveguide;

wherein the optical waveguide structure is formed of transparent electrode, and material under the transparent electrode is formed of same material as an upper cladding layer or an optical waveguide layer of a laser diode.

18. As optoelectronic device comprising:

an optical waveguide structure having at least one optical waveguide;

wherein the optical waveguide structure is formed of transparent electrode, and refractive index or thickness of the optical waveguide portion under the transparent electrode is set differently along an axis direction of the optical waveguide.

19. An optoelectronic device comprising:

an optical waveguide structure having at least one optical waveguide formed of transparent electrode; and

an impurity layer or a metal layer between the transparent electrode and underlying waveguide material to provide ohmic contact between them.

20. An optoelectronic device as claimed in claim 19, wherein a shape of the impurity layer or the metal layer between the transparent electrode and the underlying waveguide material is formed differently along an axis direction or a transverse direction.

23. An optoelectronic device comprising:

an optical waveguide structure having at least one optical waveguide;

wherein the optical waveguide structure is partly formed of transparent electrode, and

optoelectronic devices are integrated monolithically on a same substrate, and optical properties of the transparent electrodes of respective optoelectronic devices are different from device to device.

24. An optoelectronic device comprising:

an optical waveguide structure having at least one optical waveguide;

wherein the optical waveguide structure is partly formed of transparent electrode,

optoelectronic devices are integrated monolithically on a same substrate, and are formed as distributed feedback type or distributed Bragg reflector type devices each of which has an optical periodical structure along the optical waveguide, and

the optoelectronic devices oscillate outputs at different wavelengths by varying refractive indices of transparent electrodes of the optoelectronic devices respectively.

25. A laser diode device comprising:

an optical waveguide structure having at least one optical waveguide;

wherein the optical waveguide structure is partly formed of transparent electrode, and

the transparent electrode do not have a function of the optical waveguide near at least one cleaved end facet of the laser diode, but only semiconductor has the function of the optical waveguide near the at least one cleaved end surface,

otherwise both the transparent electrode and the semiconductor do not have the optical waveguide function at all near the at least one cleaved end facet of the laser diode.