Optically Pumped Semiconductor Device

• US 20080080582A1
• Filed: 04/11/2005
• Published: 04/03/2008
• 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: Karnutsch, Christian, Linder, Norbert, Schmid, Wolfgang
• Granted Patent: US 7,778,300 B2
• Time in Patent Office: Days
• US Class Current: 372/50.1
• 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, which is used to generate a pump radiation field which propagates in the lateral direction and optically pumps the vertical emitter layer in a pump region, the wavelength of the pump radiation field being smaller than the wavelength of the 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 the 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 the generation of a parasitic laterally propagating radiation field by the vertical emitter layer is suppressed.

2. The semiconductor device as claimed in claim 1, wherein

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

3. The semiconductor device as claimed in claim 2, wherein

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

4. The semiconductor device as claimed in claim 3, 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 pump layer being at a smaller distance from said side than the vertical emitter layer.

5. The semiconductor device as claimed in claim 3, wherein

a barrier having a selectivity with regard to the charge carrier type is formed between the vertical emitter layer and the pump layer.

6. The semiconductor device as claimed in claim 3, wherein

the semiconductor device is doped partly with a first conductivity type and partly with the second conductivity type and has a space charge zone, the pump layer being arranged within the space charge zone and the vertical emitter layer being arranged outside the space charge zone.

7. The semiconductor device as claimed in claim 1, wherein

the pump layer and the vertical emitter layer are arranged within a waveguide

8. The semiconductor device as claimed in claim 7, wherein

a pump mode having a filling factor Γ

_p of the pump layer and a filling factor Γ

_v of the vertical emitter layer is assigned to the waveguide outside the pump region, the filling factor of the pump layer Γ

_p being greater than the filling factor of the vertical emitter layer Γ

_v.

9. The semiconductor device as claimed in claim 7, wherein

an intensity maximum is assigned to the pump mode, and the pump layer is arranged closer to the intensity maximum than the vertical emitter layer.

10. The semiconductor device as claimed in claim 7, wherein

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

11. The semiconductor device as claimed in claim 1, wherein

within the pump region, the absorption of the pump radiation in the vertical emitter layer is increased compared with regions of the vertical emitter layer which laterally adjoin the pump region.

12. The semiconductor device as claimed in claim 11, wherein

the pump radiation field has a filling factor Γ

_p with regard to the 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.

13. The semiconductor device as claimed in claim 11, wherein

the pump layer and the vertical emitter layer are arranged within a waveguide whose wave-guiding properties are modified within the pump region compared with regions which laterally adjoin the pump region.

14. The semiconductor device as claimed in claim 13, wherein

the waveguide or layers adjoining the latter are at least partly removed within the pump region.

15. The semiconductor device as claimed in claim 11, wherein

the waveguide or layers adjoining the latter are at least partly oxidized within the pump region.

16. The semiconductor device as claimed in claim 1, wherein

the pump layer is at least partly removed within the pump region.

17. The semiconductor device as claimed in claim 1, wherein

means for suppressing vertically propagating parasitic radiation fields are provided outside the pump region.

18. The semiconductor device as claimed in claim 17, wherein

a material whose reflectivity is low enough to suppress the oscillation build-up of vertically propagating modes of parasitic radiation fields is chosen for contact metalizations.

19. The semiconductor device as claimed in claim 17, wherein

an absorber layer for suppressing vertically propagating parasitic radiation fields is provided outside the pump region.

20. The semiconductor device as claimed in claim 1, wherein

a mirror layer is arranged above or below the pump layer and the vertical emitter layer in the vertical direction.

21. The semiconductor device as claimed in claim 20, wherein

the mirror layer is oxidized within the pump region.

22. The semiconductor device as claimed in claim 20, wherein

the mirror layer is arranged between the vertical emitter layer and a substrate, and the radiation generated by the vertical emitter layer is coupled out on the opposite side to the substrate.

23. The semiconductor device as claimed in claim 20, wherein

the vertical emitter layer is arranged between the mirror layer and a substrate, and the radiation generated by the vertical emitter layer is coupled out through the substrate.

24. The semiconductor device as claimed in claim 1, wherein

an external resonator is assigned to the vertical emitter.

25. The semiconductor device as claimed in claim 20, wherein an external resonator is assigned to the vertical emitter, and the external resonator is formed by the mirror layer and an external mirror.

26. The semiconductor device as claimed in claim 24, wherein

an element for frequency conversion is arranged within the external resonator.

27. The semiconductor device as claimed in claim 1, wherein

the semiconductor device is formed in monolithically integrated fashion.