Vertical cavity surface laser and manufacturing method thereof

Abstract

This application relates to a vertical-cavity surface-mount laser and its fabrication method, belonging to the field of semiconductor technology. The fabrication method includes: providing a substrate; forming a first electrode on the substrate in an electrode region; forming a first passivation layer on the substrate and the first electrode; forming a first conductive layer on a side of the first passivation layer opposite to the substrate, wherein the orthographic projection of the first conductive layer on the substrate overlaps with the orthographic projection of the first electrode on the substrate, and extends from the overlapping portion in a direction away from the orthographic projection of the light-emitting region on the substrate; etching the first passivation layer to form a via based on a preset mask, the preset mask having a first opening, the orthographic projection of the first opening on the substrate covering the orthographic projection of the via on the substrate and extending into the orthographic projection of the first conductive layer on the substrate; and forming a second conductive layer that fills the via and covers the first conductive layer.

Claims

1. A method for fabricating a vertical-cavity surface-mount laser (VCSEL), wherein the VCSEL has at least one device region, the device region including an electrode region and a light-emitting region, the electrode region being located on one side of the light-emitting region, the method comprising: Provide a base; A first electrode is formed on the substrate in the electrode region; A first passivation layer is formed covering the substrate and the first electrode; A first conductive layer is formed on the side of the first passivation layer away from the substrate, wherein the orthographic projection of the first conductive layer on the substrate overlaps with the orthographic projection of the first electrode on the substrate, and extends from the overlapping portion toward the orthographic projection of the light-emitting area on the substrate; based on a preset mask, the first passivation layer is etched to form a via, the preset mask having a first opening, the orthographic projection of the first opening on the substrate covering the orthographic projection of the via on the substrate and extending into the orthographic projection of the first conductive layer on the substrate; and a second conductive layer is formed to fill the via and cover the first conductive layer.

2. The method for fabricating a vertical-cavity surface mount laser as described in claim 1, wherein before forming the second conductive layer that fills the via and covers the first conductive layer, the method further comprises: A second passivation layer is formed that at least covers the first passivation layer located in the light-emitting region.

3. The method for fabricating a vertical cavity surface laser as claimed in claim 1, wherein in a direction parallel to the substrate and pointing from the light-emitting region to the electrode region, the orthographic projection width of the first opening on the substrate is x1, the sum of the orthographic projection width of the first electrode on the substrate and the orthographic projection width of the first conductive layer on the substrate is x2, and x1 < x2.

4. The method for fabricating a vertical cavity surface laser as described in claim 1, wherein the device region further includes a slotted region, the slotted region being located on the side of the electrode region away from the light-emitting region; Before forming the first passivation layer covering the substrate and the first electrode, the method further includes: An oxidation-limiting groove is formed within the substrate located in the grooved area.

5. A method for fabricating a vertical-cavity surface mount laser as described in claim 4, wherein a first conductive layer is formed on the side of the first passivation layer opposite to the substrate, comprising: A first conductive layer is formed extending from above the first electrode into the oxidation confinement trench.

6. A vertical-cavity surface-mount laser, the vertical-cavity surface-mount laser having at least one device region, the device region including an electrode region and a light-emitting region, the electrode region being located on one side of the light-emitting region, the vertical-cavity surface-mount laser comprising: Base; A first electrode is located on the substrate of the electrode region; A first passivation layer covers the substrate and the first electrode, and has a through-hole exposing the first electrode; The first conductive layer is located on the side of the first passivation layer away from the substrate. The orthographic projection of the first conductive layer on the substrate overlaps with the orthographic projection of the first electrode on the substrate, and extends from the overlapping portion in a direction away from the orthographic projection of the light-emitting area on the substrate. And a second conductive layer, which fills the via and covers the first conductive layer.

7. The vertical-cavity surface mount laser as claimed in claim 6, wherein the device region further includes a slotted region located on the side of the electrode region away from the light-emitting region, and the vertical-cavity surface mount laser further includes: An oxidation limiting tank is located within the substrate of the grooved area.

8. The vertical cavity surface laser as claimed in claim 7, wherein the first conductive layer extends in a direction parallel to the substrate and from the light-emitting region to the electrode region, the orthographic projection width of the first conductive layer on the substrate is x3, the distance between the orthographic projection of the via on the substrate and the orthographic projection of the oxide confinement trench on the substrate is x4, and x3≥x4.

9. The vertical cavity surface laser as claimed in claim 8, wherein the first conductive layer extends at least from above the first electrode to the oxide confinement trench.

10. The vertical-cavity surface laser as claimed in claim 9, further comprising: The second passivation layer includes a first passivation portion and a second passivation portion; The first passivation portion is located on the surface of the substrate corresponding to the light-emitting region; The second passivation portion is located between a portion of the first conductive layer and the second conductive layer, and between a portion of the substrate and the second conductive layer. The orthographic projection of the second passivation portion on the substrate does not overlap with the orthographic projection of the via on the substrate and the orthographic projection of a portion of the first conductive layer on the substrate.

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