Vertically offset vertical cavity surface emitting lasers

Patent metadata

Field	Value
Publication number	US-12046876-B2
Application number	US-202117453060-A
Country	US
Kind code	B2
Filing date	Nov 1, 2021
Priority date	Sep 27, 2021
Publication date	Jul 23, 2024
Grant date	Jul 23, 2024

Abstract

A vertical cavity surface emitting laser (VCSEL) device may include a substrate layer and a first set of epitaxial layers, for a first VCSEL, disposed on the substrate layer. The first set of epitaxial layers may include a first set of mirrors and at least one first active layer. The VCSEL device may include a second set of epitaxial layers, for a second VCSEL, disposed on the first set of epitaxial layers for the first VCSEL. The second set of epitaxial layers may include a second set of mirrors and at least one second active layer. The first VCSEL and the second VCSEL may be configured to emit light in a light emission direction. The at least one first active layer of the first VCSEL may be offset in the light emission direction from the at least one second active layer of the second VCSEL.

First claim

What is claimed is:

1. A vertical cavity surface emitting laser (VCSEL) device, comprising:
a substrate layer;
a first set of epitaxial layers, for a first VCSEL, disposed on the substrate layer, the first set of epitaxial layers comprising:
a first set of mirrors; and
at least one first active layer;

a second set of epitaxial layers, for a second VCSEL, separate from the first set of epitaxial layers and disposed on the first set of epitaxial layers, the second set of epitaxial layers comprising:
a second set of mirrors; and
at least one second active layer,
wherein the first VCSEL and the second VCSEL are configured to emit light in a light emission direction,
wherein the at least one first active layer is offset in the light emission direction from the at least one second active layer, and
wherein the first VCSEL and the second VCSEL are configured to be operated independently; and

two unique sets of electrical contacts that do not share a common electrical contact, wherein:
a first set of electrical contacts, of the two unique sets of electrical contacts, is electrically connected to the first set of epitaxial layers, and
a second set of electrical contacts, of the two unique sets of electrical contacts, is electrically connected to the second set of epitaxial layers.

2. The VCSEL device of claim 1 , further comprising at least one of:
an electrical isolation layer between the first set of epitaxial layers and the second set of epitaxial layers;
a contact layer between the first set of epitaxial layers and the second set of epitaxial layers; or
a tunnel junction between the first set of epitaxial layers and the at least one second active layer.

3. The VCSEL device of claim 1 , further comprising:
a bulk material layer between the first set of epitaxial layers and the second set of epitaxial layers.

4. The VCSEL device of claim 1 , wherein the first set of mirrors comprise a first mirror and a second mirror, and
wherein the second set of mirrors comprise a third mirror and a fourth mirror.

5. The VCSEL device of claim 1 , wherein a first emission area of the first VCSEL and a second emission area of the second VCSEL are offset in a direction orthogonal to the light emission direction.

6. The VCSEL device of claim 1 , wherein a first emission area of the first VCSEL and a second emission area of the second VCSEL are aligned in a direction orthogonal to the light emission direction.

7. The VCSEL device of claim 6 , wherein a first emission wavelength of the first VCSEL is different from a second emission wavelength of the second VCSEL.

8. The VCSEL device of claim 1 , wherein a first quantity of active layers of the at least one first active layer is different from a second quantity of active layers of the at least one second active layer.

9. The VCSEL device of claim 1 , wherein the first VCSEL and the second VCSEL are configured for bottom emission, and
wherein a surface of the substrate layer opposite the first set of epitaxial layers comprises an optical element for at least one of the first VCSEL or the second VCSEL.

10. The VCSEL device of claim 1 , wherein the first VCSEL is horizontally offset, along a direction orthogonal to the light emission direction, from the second VCSEL.

11. A vertical cavity surface emitting laser (VCSEL) array, comprising:
a substrate layer;
a first set of epitaxial layers, for a plurality of first VCSELs, disposed on the substrate layer, the first set of epitaxial layers comprising:
a first set of mirrors; and
at least one first active layer;

a second set of epitaxial layers, for a plurality of second VCSELs, disposed on the first set of epitaxial layers, the second set of epitaxial layers comprising:
a second set of mirrors; and
at least one second active layer,
wherein the plurality of first VCSELs and the plurality of second VCSELs are configured to emit light in a light emission direction,
wherein a surface of the first set of epitaxial layers is offset in the light emission direction from a surface of the second set of epitaxial layers, and
wherein the plurality of first VCSELs and the plurality of second VCSELs are configured to be operated independently; and

two unique sets of electrical contacts that do not share a common electrical contact, wherein
a first set of electrical contacts, of the two unique sets of electrical contacts, is electrically connected to the first set of epitaxial layers, and
a second set of electrical contacts, of the two unique sets of electrical contacts, is electrically connected to the second set of epitaxial layers.

12. The VCSEL array of claim 11 , wherein a first bottom mirror of the first set of mirrors and a second bottom mirror of the second set of mirrors are one of n-type or p-type,
wherein a first top mirror of the first set of mirrors and a second top mirror of the second set of mirrors are the other of n-type or p-type, and
wherein a tunnel junction is between the first set of epitaxial layers and the at least one second active layer.

13. The VCSEL array of claim 11 , wherein a first quantity of active layers of the at least one first active layer is different from a second quantity of active layers of the at least one second active layer.

14. The VCSEL array of claim 11 , wherein a first emission wavelength of the plurality of first VCSELs is different from a second emission wavelength of the plurality of second VCSELs.

15. The VCSEL array of claim 11 , wherein the plurality of first VCSELs are arranged in a first pattern and the plurality of second VCSELs are arranged in a second pattern, and
wherein the first pattern is interleaved with the second pattern in a direction orthogonal to the light emission direction.

16. The VCSEL array of claim 11 , wherein the plurality of first VCSELs are arranged in a first pattern and the plurality of second VCSELs are arranged in a second pattern, and
wherein the first pattern surrounds the second pattern in a direction orthogonal to the light emission direction.

17. The VCSEL array of claim 11 , wherein a first VCSEL, of the plurality of first VCSELs, is horizontally offset from a second VCSEL, of the plurality of second VCSELs, along a direction orthogonal to the light emission direction.

18. A method, comprising:
growing, on a substrate layer, a first set of epitaxial layers for a first VCSEL, the first set of epitaxial layers comprising:
a first set of mirrors; and
at least one first active layer;

growing, on the first set of epitaxial layers, a second set of epitaxial layers for a second VCSEL, the second set of epitaxial layers comprising:
a second set of mirrors; and
at least one second active layer;

etching a portion of the second set of epitaxial layers until a surface of the first set of epitaxial layers is exposed,
wherein the first VCSEL and the second VCSEL are configured to emit light in a light emission direction,
wherein the at least one first active layer of the first VCSEL is offset in the light emission direction from the at least one second active layer of the second VCSEL, and
wherein the first VCSEL and the second VCSEL are configured to be operated independently; and

depositing two unique sets of metal contacts that do not share a common electrical contact, wherein
a first set of metal contacts, of the two unique sets of metal contacts, is electrically connected to the first set of epitaxial layers, and
a second set of metal contacts, of the two unique sets of electrical contacts, is electrically connected to the second set of epitax

Assignees

• Lumentum Operations Llc

Inventors

• Kesler Benjamin
• Zhao Guowei

Classifications

• H01S5/3416

  tunneling through barriers · CPC title

• H01S5/0421

  characterised by the semiconducting contacting layers (electrodes H01S5/0425) · CPC title

• H01S5/18397

  Plurality of active layers vertically stacked in a cavity for multi-wavelength emission · CPC title

• H01S5/18305

  with emission through the substrate, i.e. bottom emission · CPC title

• H01S5/04257

  having positive and negative electrodes on the same side of the substrate · CPC title