CN-120165299-B - Vertical cavity surface emitting laser and preparation method thereof

CN120165299BCN 120165299 BCN120165299 BCN 120165299BCN-120165299-B

Abstract

The embodiment of the application relates to a vertical cavity surface emitting laser and a preparation method thereof, and particularly comprises a first conductive semiconductor layer, an active layer and a second conductive semiconductor layer which are sequentially stacked, a current injection blocking layer is further stacked, a current injection channel is formed in the current injection blocking layer, a second electrode contact part, a transparent conductive film and a heavily doped semiconductor material part which are positioned on the upper surface side of the second conductive semiconductor layer, wherein the projection of the heavily doped semiconductor material part falls into the projection range of the current injection channel along the stacking direction, the projection of the second electrode contact part is not overlapped with the projection of the current injection channel, one part of the transparent conductive film is in conductive connection with the second electrode contact part, and the other part of the transparent conductive film is in conductive connection with the second conductive semiconductor layer through the heavily doped semiconductor material part. Thus, the control of current distribution is better realized, and the light-emitting divergence angle of the VCSEL is optimized.

Inventors

ZHAO WENJIAN

Assignees

芯联越州集成电路制造（绍兴）有限公司

Dates

Publication Date: 20260512
Application Date: 20250320

Claims (10)

1. A vertical cavity surface emitting laser, comprising: A first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer which are sequentially stacked, a current injection blocking layer being further stacked between the first conductive semiconductor layer and the active layer and/or between the second conductive semiconductor layer and the active layer, a current injection channel being formed in the current injection blocking layer, the second conductive semiconductor layer having an upper surface remote from the current injection blocking layer; a second electrode contact portion, a transparent conductive film, and a heavily doped semiconductor material portion on an upper surface side of the second conductive semiconductor layer; Wherein, the In the stacking direction, the projection of the heavily doped semiconductor material part falls within the projection range of the current injection channel, and the projection of the second electrode contact part is not overlapped with the projection of the current injection channel; And one part of the transparent conductive film is in conductive connection with the second electrode contact part, the other part of the transparent conductive film is in conductive connection with the second conductive semiconductor layer through the heavily doped semiconductor material part, and current flowing into the second conductive semiconductor layer enters the active layer through the current injection channel.
2. The vertical cavity surface emitting laser according to claim 1, wherein said heavily doped semiconductor material portion is in direct contact with an upper surface of said second conductive semiconductor layer, said transparent conductive film overlies said heavily doped semiconductor material portion and said second conductive semiconductor layer, and said second electrode contact is on said transparent conductive film.
3. The vertical cavity surface emitting laser according to claim 1, wherein, in the lamination direction, The projected centre of the heavily doped semiconductor material portion coincides with the projected centre of the current injection channel and/or, The projection of the heavily doped semiconductor material portion is circular or annular.
4. The vcl as claimed in claim 1, wherein the transparent conductive film comprises ITO.
5. The vertical cavity surface emitting laser according to claim 1, further comprising at least one transparent material layer laminated on a side of said transparent conductive film remote from said second conductive semiconductor layer, said transparent conductive film satisfying: , Wherein, the For the refractive index of the transparent conductive film, For the thickness of the transparent conductive film, Is the first The refractive index of the layer of transparent material, Is the first The thickness of the layer of transparent material, Is a positive integer which is used for the preparation of the high-voltage power supply, Is the total number of layers of the transparent material, Is a positive integer which is used for the preparation of the high-voltage power supply, Is the light emitting wavelength of the vertical cavity surface emitting laser.
6. A method of fabricating a vertical cavity surface emitting laser, the method comprising: providing a first conductive semiconductor layer, an active layer and a second conductive semiconductor layer which are sequentially stacked, wherein a current injection barrier layer is further stacked between the first conductive semiconductor layer and the active layer and/or between the second conductive semiconductor layer and the active layer, and a current injection channel forming position is arranged in the current injection barrier layer; And forming a second electrode contact part, a transparent conductive film and a heavily doped semiconductor material part on the second conductive semiconductor layer, wherein the projection of the heavily doped semiconductor material part falls into the projection range of the current injection channel forming position along the stacking direction, the projection of the second electrode contact part is not overlapped with the projection of the current injection channel forming position, one part of the transparent conductive film is in conductive connection with the second electrode contact part, and the other part of the transparent conductive film is in conductive connection with the second conductive semiconductor layer through the heavily doped semiconductor material part.
7. The method of manufacturing a vertical cavity surface emitting laser according to claim 6, wherein forming a second electrode contact portion, a transparent conductive film, and a heavily doped semiconductor material portion on the second conductive semiconductor layer comprises: forming a heavily doped semiconductor material layer on an upper surface of the second conductive semiconductor layer in direct contact with the second conductive semiconductor layer; patterning the heavily doped semiconductor material layer to form the heavily doped semiconductor material portion; Forming the transparent conductive film covering the heavily doped semiconductor material portion and the second conductive semiconductor layer; forming the second electrode contact on the transparent conductive film; the method further comprises the steps of: And forming a groove exposing the current injection blocking layer, oxidizing the current injection blocking layer through the groove, and forming the current injection channel at the unoxidized part of the center of the current injection blocking layer.
8. The method of manufacturing a vertical cavity surface emitting laser according to claim 6, wherein, in the lamination direction, The projected centre of the heavily doped semiconductor material portion coincides with the projected centre of the current injection channel and/or, The projection of the heavily doped semiconductor material portion is circular or annular.
9. The method of manufacturing a vertical cavity surface emitting laser according to claim 6, wherein the transparent conductive film comprises ITO.
10. The method of manufacturing a vertical cavity surface emitting laser according to claim 6, further comprising: Forming at least one transparent material layer on the upper surface of the transparent conductive film; the transparent conductive film satisfies: , Wherein, the For the refractive index of the transparent conductive film, For the thickness of the transparent conductive film, Is the first The refractive index of the layer of transparent material, Is the first The thickness of the layer of transparent material, Is a positive integer which is used for the preparation of the high-voltage power supply, Is the total number of layers of the transparent material, Is a positive integer which is used for the preparation of the high-voltage power supply, Is the light emitting wavelength of the vertical cavity surface emitting laser.

Description

Vertical cavity surface emitting laser and preparation method thereof Technical Field The application relates to the technical field of semiconductors, in particular to a vertical cavity surface emitting laser and a preparation method thereof. Background A Vertical-Cavity Surface-emitting laser (Vertical-Cavity Surface-EMITTING LASER, VCSEL) is a semiconductor laser, and its laser emitting direction is perpendicular to the epitaxial plane, unlike a general edge-emitting laser, the VCSEL has advantages of small far-field divergence angle, easy optical fiber coupling, small threshold current, high bandwidth, and high test efficiency. However, in practical applications, the divergence angle of the light emitted by the VCSEL chip becomes a technical index that needs to be focused, and especially in application scenarios with strict requirements on the beam quality, the control of the divergence angle is critical. In order to optimize the divergence angle, the art has explored several effective technical approaches. For example, the convergence of emergent light can be realized by adding an optical lens on the emergent surface of the VCSEL, so that the divergence angle is reduced, or the epitaxial surface layer of the VCSEL is subjected to shallow etching treatment, and the divergence angle is further controlled by inhibiting the emergent light of an unetched area. However, the improvement of VCSEL chips on the optical path alone is not yet sufficient to meet the optimization requirements of divergence angle. In a typical VCSEL structure, to avoid the center of the aperture being blocked, the metal electrode can only be made on the outer ring of the aperture, so that current can only be injected from the periphery of the aperture, resulting in a current density at the edge of the aperture that is greater than the current density at the center of the aperture. The non-uniformity of the current distribution may exacerbate the divergence of the beam, causing a further increase in the divergence angle, thereby affecting the beam quality and application of the VCSEL. Therefore, how to further optimize the light emission divergence angle of the VCSEL, and particularly to realize control of current distribution in structural design, is an important issue to be solved in the art. Disclosure of Invention In view of the above, embodiments of the present application provide a vertical cavity surface emitting laser and a method for manufacturing the same, which solve at least one of the problems in the prior art. In a first aspect, an embodiment of the present application provides a vertical cavity surface emitting laser, including: A first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer which are sequentially stacked, a current injection blocking layer being further stacked between the first conductive semiconductor layer and the active layer and/or between the second conductive semiconductor layer and the active layer, a current injection channel being formed in the current injection blocking layer, the second conductive semiconductor layer having an upper surface remote from the current injection blocking layer; a second electrode contact portion, a transparent conductive film, and a heavily doped semiconductor material portion on an upper surface side of the second conductive semiconductor layer; Wherein, the In the stacking direction, the projection of the heavily doped semiconductor material part falls within the projection range of the current injection channel, and the projection of the second electrode contact part is not overlapped with the projection of the current injection channel; And one part of the transparent conductive film is in conductive connection with the second electrode contact part, and the other part of the transparent conductive film is in conductive connection with the second conductive semiconductor layer through the heavily doped semiconductor material part. In combination with the first aspect of the present application, in an alternative embodiment, the heavily doped semiconductor material portion is in direct contact with the upper surface of the second conductive semiconductor layer, the transparent conductive film covers the heavily doped semiconductor material portion and the second conductive semiconductor layer, and the second electrode contact portion is located on the transparent conductive film. In combination with the first aspect of the present application, in an alternative embodiment, in the stacking direction, The projected centre of the heavily doped semiconductor material portion coincides with the projected centre of the current injection channel and/or, The projection of the heavily doped semiconductor material portion is circular or annular. In combination with the first aspect of the present application, in an alternative embodiment, the material of the transparent conductive film includes ITO. With reference to the first aspec