Angled flip-chip bump layout

Patent metadata

Field	Value
Publication number	US-11923653-B2
Application number	US-202117192470-A
Country	US
Kind code	B2
Filing date	Mar 4, 2021
Priority date	Dec 23, 2020
Publication date	Mar 5, 2024
Grant date	Mar 5, 2024

Abstract

In some implementations, an optical device for mounting in a flip-chip configuration includes a plurality of flip-chip bumps that are arranged in a pattern on the optical device, wherein the pattern is not aligned with a crystal cleavage plane associated with a substrate of the optical device. In some implementations, the optical device further includes a gap that separates a primary region of the optical device and a secondary region of the optical device, wherein at least one portion of a side of the gap is oriented at a non-zero angle to the crystal cleavage plane.

First claim

What is claimed is:

1. An optical device for mounting in a flip-chip configuration, comprising:
a primary region;
a secondary region; and
a gap that separates the primary region and the secondary region, wherein:
a first portion of a side of the gap is oriented at a first non-zero angle to a crystal cleavage plane associated with a substrate of the optical device,
a second portion of the side of the gap is oriented at a second non-zero angle to the crystal cleavage plane,
the first non-zero angle is different from the second non-zero angle, and
more than two portions of the side of the gap intersect the crystal cleavage plane.

2. The optical device of claim 1 , wherein the first non-zero angle is within a range of 5 to 15 degrees.

3. The optical device of claim 1 , further comprising a plurality of flip-chip bumps that are arranged in a pattern on at least one of the primary region and the secondary region.

4. The optical device of claim 1 , wherein the optical device is a vertical-cavity surface-emitting laser (VCSEL) optical device.

5. The optical device of claim 1 , wherein the primary region is associated with an anode associated with the optical device and the secondary region is associated with a cathode associated with the optical device.

6. The optical device of claim 1 , wherein the orientation of the first portion of the side of the gap causes an amount of mechanical stress along the crystal cleavage plane to satisfy a mechanical stress breakage threshold,
wherein the amount of mechanical stress is created by attachment of the primary region and the secondary region to a component of another device.

7. The optical device of claim 1 , wherein the gap extends from within a threshold distance of a first side of the optical device to within the threshold distance of a second side of the optical device.

8. The optical device of claim 3 , wherein the pattern is not aligned with the crystal cleavage plane.

9. The optical device of claim 3 , wherein the pattern comprises multiple rows of flip-chip bumps,
wherein adjacent rows, of the multiple rows, are laterally offset from each other.

10. The optical device of claim 3 , wherein the pattern is a non-uniform pattern.

11. The optical device of claim 1 , wherein the second non-zero angle is within a range of 5 to 15 degrees.

12. The optical device of claim 1 , wherein the side of the gap has a sinusoidal shape.

13. A wafer, comprising:
a plurality of chips that include a plurality of gaps; and
a crystal cleavage plane associated with the wafer, wherein:
a first portion of a side of a gap of the plurality of gaps is oriented at a first non-zero angle to the crystal cleavage plane,
a second portion of the side of the gap is oriented at a second non-zero angle to the crystal cleavage plane,
the first non-zero angle is different from the second non-zero angle, and
more than two portions of the side of the gap intersect the crystal cleavage plane.

14. The wafer of claim 13 , wherein the plurality of chips include a plurality of chip bumps, wherein:
the plurality of chip bumps are arranged in a pattern on the plurality of chips.

15. The wafer of claim 14 , wherein the pattern of chip bumps is a result of a rotation, relative to the wafer, of a mask used to manufacture the plurality of chip bumps.

16. The wafer of claim 14 , wherein the pattern comprises a non-uniform pattern of chip bumps.

17. The wafer of claim 14 , wherein the pattern comprises multiple rows of chip bumps,
wherein adjacent rows, of the multiple rows, are laterally offset from each other.

18. The wafer of claim 14 , wherein the pattern comprises a uniform pattern of chip bumps.

19. The wafer of claim 13 , wherein the side of the gap has a sinusoidal shape.

20. The wafer of claim 13 , wherein at least one of the first non-zero angle or the second non-zero angle is within a range of 5 to 15 degrees.

21. The wafer of claim 13 , wherein the plurality of chips are vertical-cavity surface-emitting laser (VCSEL) chips.

22. The wafer of claim 13 , wherein the orientation of the first portion of the side of the gap causes an amount of mechanical stress along the crystal cleavage plane to satisfy a mechanical stress breakage threshold.

Assignees

• Lumentum Operations Llc

Inventors

• Yuen Albert
• Srimongkol Mitchell
• Lin Joseph

Classifications

• H01S5/0234 Primary

  Up-side down mountings, e.g. Flip-chip, epi-side down mountings or junction down mountings · CPC title

• H01S5/423

  having a vertical cavity · CPC title

• H01S5/183

  having only vertical cavities, e.g. vertical cavity surface-emitting lasers [VCSEL] · CPC title

• H01S5/0232 Primary

  Lead-frames · CPC title

• H01S5/02345

  Wire-bonding · CPC title