High-power vertical cavity surface emitting laser cluster

• US 5,812,571 A
• Filed: 10/25/1996
• Issued: 09/22/1998
• Est. Priority Date: 10/25/1996
• Status: Expired due to Term

• Current Assignee: Regents of the University of California (University of California), W. L. Gore & Associates (W.L. Gore & Associates)
• Original Assignee: W. L. Gore & Associates (W.L. Gore & Associates)
• Inventors: Peters, Frank H.
• Primary Examiner(s): Bovernick, Rodney B.
• Assistant Examiner(s): LEUNG, QUYEN PHAN
• Application Number:
  US08/739,108
• Time in Patent Office: 697 Days
• Field of Search: 372/36, 372/45, 372/50, 372/96, 372/72, 372/75, 385/88-94, 437/129, 359/154, 219/540
• US Class Current: 372/36
• CPC Class Codes: G02B 6/421 the intermediate optical component consisting of a short length of fibre, e.g. fibre stub
• CPC Class Codes: H01S 5/02212 Can-type, e.g. TO-CAN housings with emission along or parallel to symmetry axis
• CPC Class Codes: H01S 5/02251 using optical fibres
• CPC Class Codes: H01S 5/0234 Up-side down mountings, e.g. Flip-chip, epi-side down mountings or junction down mountings
• CPC Class Codes: H01S 5/02461 Structure or details of the laser chip to manipulate the heat flow, e.g. passive layers in the chip with a low heat conductivity
• CPC Class Codes: H01S 5/02484 Sapphire or diamond heat spreaders
• CPC Class Codes: H01S 5/18305 with emission through the substrate, i.e. bottom emission
• CPC Class Codes: H01S 5/423 having a vertical cavity

Abstract

A laser cluster for high-power applications includes an array of VCSELs. The array of VCSELs includes a center VCSEL and one or more peripheral VCSELs displaced from the center VCSEL in a hexagonal closest-packing arrangement sharing a pair of common electrical contacts. Each VCSEL in the array is flip-chip mounted on a heat sink to present the backside of the VCSEL. A multimode optical fiber is coupled to receive laser light from the array of VCSELs. The array of VCSELs is operable to generate a laser burst at a wavelength in a range from 950 nm to 1050 nm. In a process for fabricating a VCSEL that can be clustered for high-power applications, a bottom n-doped mirror stack is deposited above an n-doped gallium arsenide substrate. An active region including indium gallium arsenide is deposited above the bottom mirror stack. A top p-doped mirror stack is deposited above the active region. Electrical contacts are applied to the top mirror stack and to the substrate. The laser cluster is packaged and sealed.

Claims

1. A laser cluster for high-power applications, comprising:

an array of VCSELs including a center VCSEL and one or more peripheral VCSELs displaced from the center VCSEL; and

a pair of common electrical contacts shared by said array of VCSELs;

wherein the VCSELs in said array are separated by a distance in a range from about 10 mm to about 40 mm.

3. A laser cluster as defined in claims 1 or 2, wherein:

each VCSEL in said array is mounted on a heat sink.

4. A laser cluster as defined in claims 1 or 2, further comprising:

a multimode optical fiber coupled to receive light emitted from said array.

2. A laser cluster for high-power applications, comprising:

an array of VCSELs including a center VCSEL and one or more peripheral VCSELs displaced from the center VCSEL; and

a pair of common electrical contacts shared by said array of VCSELs;

wherein each VCSEL in said array presents an emitting facet having a diameter in a range from about 5 mm to about 30 mm.

5. A process of fabricating a laser cluster for high-power applications, comprising the following steps:

(A) providing an array of VCSELs in a hexagonal closest-packing arrangement;

(B) connecting the array of VCSELs to a pair of common electrical contacts; and

(C) coupling the array of VCSELs into a multimode optical fiber;

wherein each VCSEL in the array presents an emitting facet having a diameter in a range from about 5 mm to about 30 mm, and

the VCSELs in the array are separated by a distance in a range from about 10 mm to about 40 mm.

6. A process as defined in claim 5, further comprising the step:

mounting the array of VCSELs on a heat sink.

7. A process as defined in claim 5, wherein:

each VCSEL in the array is a bottom-emitting VCSEL, and further comprising the step of;

flip-chip mounting the array of VCSELs on a heat sink.

8. A package for a laser cluster, comprising:

a housing;

a submount in said housing;

a laser cluster including an array of VCSELs mounted junction-side down on said submount so that said laser cluster presents a backside emitting surface; and

a multimode optical fiber including a core, said multimode optical fiber passing through said housing and coupled onto said backside emitting surface;

said laser cluster includes seven VCSELs positioned within a circular area, said circular area having a diameter which is substantially equal to the diameter of said core.

9. A package as defined in claim 8, further comprising:

common ground and ignition contacts which are electrically connected through said submount to said laser cluster.

10. A package as defined in claim 8, wherein:

each of said array of VCSELs is capable of emitting coherent electromagnetic radiation having a wavelength in a range from 950 nm to 1050 nm.

11. A package as defined in claim 8, wherein:

said submount includes aluminum nitride.

12. A process of fabricating a laser cluster for high-power applications, comprising the following steps:

(A) providing an array of VCSELs;

(B) connecting the array of VCSELs to a pair of common electrical contacts; and

(C) coupling the array of VCSELs into a multimode optical fiber;

wherein each VCSEL in the array presents an emitting facet having a diameter in a range from about 5 mm to about 30 mm.

13. A process of fabricating a laser cluster for high-power applications, comprising the following steps:

(A) providing an array of VCSELs;

(B) connecting the array of VCSELs to a pair of common electrical contacts; and

(C) coupling the array of VCSELs into a multimode optical fiber;

wherein the VCSELs in the array are separated by a distance in a range from about 10 mm to about 40 mm.