Optically pumped semiconductor device

• US 7,778,300 B2
• Filed: 04/11/2005
• Issued: 08/17/2010
• Est. Priority Date: 04/30/2004
• Status: Active Grant

• Current Assignee: Osram Opto Semiconductors GmbH (Ams-Osram AG)
• Original Assignee: Osram Opto Semiconductors GmbH (Ams-Osram AG)
• Inventors: Linder, Norbert, Karnutsch, Christian, Schmid, Wolfgang
• Primary Examiner(s): VAN ROY, TOD THOMAS
• Application Number:
  US11/579,196
• Publication Number:
  US 20080080582A1
• Time in Patent Office: 1,954 Days
• Field of Search: 372/50.124, 372/69, 372/70, 372/75
• US Class Current: 372/50.124
• 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 5/041 Optical pumping
• CPC Class Codes: H01S 5/141 using a wavelength selective device, e.g. a grating or etalon H01S5/146 takes precedence
• CPC Class Codes: H01S 5/18305 with emission through the substrate, i.e. bottom emission
• CPC Class Codes: H01S 5/18313 by oxidizing at least one of the DBR layers
• CPC Class Codes: H01S 5/18327 Structure being part of a DBR H01S5/18391 takes precedence
• CPC Class Codes: H01S 5/18388 Lenses
• CPC Class Codes: H01S 5/32341 blue laser based on GaN or GaP

Abstract

A semiconductor device comprising an optically pumped vertical emitter having an active vertical emitter layer (3), and a pump radiation source, which is used to generate a pump radiation field which propagates in the lateral direction and optically pumps the vertical emitter layer (3) in a pump region, the wavelength of the pump radiation field being smaller than the wavelength of the radiation field (12) generated by the vertical emitter. The pump radiation source has an active pump layer (2), which is arranged downstream of the vertical emitter layer (3) in the vertical direction and which at least partly overlaps the vertical emitter layer as seen in the vertical direction, the active pump layer (2) being arranged in such a way that the pump radiation field generated during operation has a higher power than a parasitic laterally propagating radiation field generated by the vertical emitter layer (3) or that the generation of a parasitic laterally propagating radiation field by the vertical emitter layer (3) is suppressed.

Claims

1. A semiconductor device comprising:

an optically pumped vertical emitter having an active vertical emitter layer, and

a pump radiation source used to generate a pump radiation field which propagates in a lateral direction and optically pumps the vertical emitter layer in a pump region, a wavelength of the pump radiation field being smaller than a wavelength of a radiation field generated by the vertical emitter,

wherein the pump radiation source has an active pump layer, which is arranged above or below the vertical emitter layer in a vertical direction and which at least partly overlaps the vertical emitter layer as seen in the vertical direction, the active pump layer being arranged in such a way that the pump radiation field generated during operation has a higher power than a parasitic laterally propagating radiation field generated by the vertical emitter layer or that generation of a parasitic laterally propagating radiation field by the vertical emitter layer is suppressed,

wherein the pump radiation source is electrically excited by charge carrier injection for generation of the pump radiation,

wherein charge carriers of a first charge carrier type and charge carriers of a second charge carrier type are injected into the semiconductor device, and

wherein the charge carriers of the first charge carrier type have a higher net trapping rate than the charge carriers of the second charge carrier type and are injected into the semiconductor device from a side, the active pump layer being at a smaller distance from said side than from the vertical emitter layer.

2. The semiconductor device as claimed in claim 1, further comprising a barrier having a selectivity with regard to the charge carrier types formed between the vertical emitter layer and the active pump layer.

3. The semiconductor device as claimed in claim 1, wherein the semiconductor device is doped partly with a first conductivity type and partly with a second conductivity type and has a space charge zone, the active pump layer being arranged within the space charge zone and the vertical emitter layer being arranged outside the space charge zone.

4. The semiconductor device as claimed in claim 1, further comprising a waveguide, wherein both the active pump layer and the vertical emitter layer are arranged within the waveguide.

5. The semiconductor device as claimed in claim 4, wherein the waveguide is assigned a pump mode having a filling factor Γ

_p of the active pump layer and a filling factor Γ

_v of the vertical emitter layer outside the pump region, the filling factor Γ

_p of the active pump layer being greater than the filling factor Γ

_v of the vertical emitter layer.

6. The semiconductor device as claimed in claim 5, wherein an intensity maximum is assigned to the pump mode, and the active pump layer is arranged closer to the intensity maximum than is the vertical emitter layer.

7. The semiconductor device as claimed in claim 5, wherein the pump mode has a zero crossing, and the vertical emitter layer is arranged closer to the zero crossing than to the active pump layer.

8. The semiconductor device as claimed in claim 1, wherein within the pump region, an absorption of a pump radiation in the vertical emitter layer is increased compared with regions of the vertical emitter layer which laterally adjoin the pump region.

9. The semiconductor device as claimed in claim 8, wherein the pump radiation field has a filling factor Γ

_p with regard to the active pump layer and a filling factor Γ

_v with regard to the vertical emitter layer, the ratio Γ

_p/Γ

_v being decreased within the pump region compared with regions of the vertical emitter layer which laterally adjoin the pump region.

10. The semiconductor device as claimed in claim 8, wherein the active pump layer and the vertical emitter layer are arranged within a waveguide, the waveguide having wave-guiding properties modified within the pump region compared with regions which laterally adjoin the pump region.

11. The semiconductor device as claimed in claim 10, wherein the waveguide or layers adjoining the waveguide are at least partly removed within the pump region.

12. The semiconductor device as claimed in claim 10, wherein the waveguide or layers adjoining the waveguide are at least partly oxidized within the pump region.

13. The semiconductor device as claimed in claim 1, wherein the active pump layer is at least partly removed within the pump region.

14. The semiconductor device as claimed in claim 1, further comprising means for suppressing vertically propagating parasitic radiation fields, wherein the suppressing means are provided outside the pump region.

15. The semiconductor device as claimed in claim 14, wherein a material whose reflectivity is low enough to suppress an oscillation build-up of vertically propagating modes of parasitic radiation fields is chosen for contact metalizations.

16. The semiconductor device as claimed in claim 14, further comprising an absorber layer for suppressing vertically propagating parasitic radiation fields, wherein the absorber layer is provided outside the pump region.

17. The semiconductor device as claimed in claim 1, further comprising a mirror layer arranged above or below the active pump layer and the vertical emitter layer in the vertical direction.

18. The semiconductor device as claimed in claim 17, wherein the mirror layer is oxidized within the pump region.

19. The semiconductor device as claimed in claim 17, wherein the mirror layer is arranged between the vertical emitter layer and a substrate, and a radiation generated by the vertical emitter layer is coupled out from an opposite side to the substrate.

20. The semiconductor device as claimed in claim 17, wherein the vertical emitter layer is arranged between the mirror layer and a substrate, and a radiation generated by the vertical emitter layer is coupled out through the substrate.

21. The semiconductor device as claimed in claim 17, further comprising an external resonator assigned to the vertical emitter, wherein the external resonator is formed by the mirror layer and an external mirror.

22. The semiconductor device as claimed in claim 1, further comprising an external resonator assigned to the vertical emitter.

23. The semiconductor device as claimed in claim 22, further comprising an element for frequency conversion arranged within the external resonator.

24. The semiconductor device as claimed in claim 1, wherein the semiconductor device is formed in monolithically integrated fashion.

25. A semiconductor device comprising:

an optically pumped vertical emitter having an active vertical emitter layer;

a pump radiation source used to generate a pump radiation field which propagates in a lateral direction and optically pumps the vertical emitter layer in a pump region, a wavelength of the pump radiation field being smaller than a wavelength of a radiation field generated by the vertical emitter; and

a waveguide;

wherein the pump radiation source has an active pump layer, which is arranged above or below the vertical emitter layer in a vertical direction and which at least partly overlaps the vertical emitter layer as seen in the vertical direction, the active pump layer being arranged in such a way that the pump radiation field generated during operation has a higher power than a parasitic laterally propagating radiation field generated by the vertical emitter layer or that generation of a parasitic laterally propagating radiation field by the vertical emitter layer is suppressed,

wherein both the active pump layer and the vertical emitter layer are arranged within the waveguide, and

wherein the waveguide is assigned a pump mode having a filling factor Γ

_p of the active pump layer and a filling factor Γ

_v of the vertical emitter layer outside the pump region, the filling factor Γ

_p of the active pump layer being greater than the filling factor Γ

_v of the vertical emitter layer, and

wherein the pump mode has a zero crossing, and the vertical emitter layer is arranged closer to the zero crossing than to the active pump layer.