VCSEL with integrated lens
View Patent ↗A wafer-level device fabrication process forms standing structures around emitting areas of multiple VCSELs. The standing structures can be shaped to hold ball lenses or other optical elements for respective VCSELs or can include platforms on which optical elements are formed. Ball lenses that are attached to the standing structures either during chip-level or wafer-level processes fit into the standing structures and are automatically aligned. Wafer level fabrication of optical elements can align the optical elements with accuracies associated with photolithographic processes. The optical elements can be formed using a molding or replication process, a printing method, or surface tension during a reflow of lithographically formed regions.
1. A device comprising:
a substrate containing a laser diode;
a standing structure attached to the substrate, wherein the standing structure comprises
a standoff comprising at least one pillar attached to the substrate, and
a plate on which the lens resides, the plate being supported by the at least one pillar; and
a lens formed on the standing structure and overlying an emitting area through which a beam from the laser diode emerges from the substrate.
2. The device of claim 1 , further comprising:
a plurality of laser diodes in the substrate, and
a plurality of standing structures attached to the substrate; and
a plurality of lenses formed on the standing structures, each of the lenses overlying an emitting area through which a beam from a corresponding one of the laser diode emerges from the substrate.
3. The device of claim 1 , wherein the substrate comprises a die cut from a wafer.
4. The device of claim 1 , wherein the plate comprises a plate of a first material and the at least one pillar comprises at least one pillar of a second material.
5. The device of claim 4 , wherein the first material is glass, and the second material is a polymer.
6. The device of claim 1 , wherein the platform and the standoff are portions of a unified structure and formed of a common material.
7. The device of claim 1 , wherein the standing structure provides an air gap between the emitting area of the laser diode and the platform.
8. The device of claim 1 , wherein the standing structure comprises a pillar formed on the emitting area of the laser diode, and the platform comprises a top surface of the pillar.
9. The device of claim 1 , wherein the lens has an optical surface shaped by molding.
10. The device of claim 1 , wherein the lens has an optical surface shaped when material in the lens was liquid.
11. The device of claim 10 , wherein the lens element comprises a material cured through exposure to UV light.
12. The device of claim 11 , further comprising an optical fiber positioned to receive the beam from the laser diode after the lens focuses the beam.