Wafer-level packaging of optoelectronic devices
View Patent ↗In an embodiment, the invention provides a method for forming a wafer-level package. A bonding pad is formed on a first wafer. After forming the bonding pad, an optoelectronic device is located on the first wafer. A gasket is formed on a second wafer. After a gasket is formed on a second wafer, the second wafer is attached to the first wafer with a bond between the gasket and the bonding pad.
1. A method for forming a wafer-level package, comprising:
forming a bonding pad on a first wafer;
locating a light-emitting device on the first wafer;
forming a gasket on a second wafer;
forming an integrated lens as part of one of the first and the second wafers; and
attaching the second wafer to the first wafer with a bond between the gasket and the bonding pad.
2. The method of claim 1 , wherein said locating the light-emitting device comprises one of attaching the light-emitting device on the first wafer and forming the light-emitting device on the first wafer.
3. The method of claim 1 , further comprising forming a mirror in the second wafer for reflecting a light from the light-emitting device through the integrated lens in the first wafer.
4. The method of claim 1 , further comprising:
forming a contact pad on the first wafer; and
forming a via contact through the second wafer and coupled to the contact pad.
5. The method of claim 1 , further comprising forming a cavity in the second wafer for accommodating the light-emitting device.
6. The method of claim 1 , further comprising forming a bonding layer on the gasket, wherein the bond between the bonding layer and the bonding pad comprises a thermocompression bond.
7. The method of claim 6 , further comprising forming a barrier metal layer between at least one of (1) the bonding layer and the gasket, and (2) the bonding pad and the first wafer.
8. The method of claim 1 , wherein the bond is selected from the group consisting of a reaction bond and a solder bond.
9. The method of claim 1 , further comprising forming a treaded surface on the gasket.
10. The method of claim 1 , wherein the light-emitting device is selected from the group consisting of an edge-emitting laser and a vertical cavity surface-emitting laser (VCSEL).
11. The method of claim 1 , wherein the integrated lens comprises a diffractive optical element.
12. A method for forming a wafer-level package, comprising:
forming a bonding pad on a first wafer;
locating a light-emitting device on the first wafer;
forming a gasket on a second wafer;
forming a mirror in the second wafer for reflecting a light from the light-emitting device through the first wafer; and
attaching the second wafer to the first wafer with a bond between the gasket and the bonding pad.
13. The method of claim 12 , wherein said locating the light-emitting device comprises one of attaching the light-emitting device on the first wafer and forming the light-emitting device on the first wafer.
14. The method of claim 12 , further comprising:
forming a contact pad on the first wafer; and
forming a via contact through the second wafer and coupled to the contact pad.
15. The method of claim 12 , further comprising forming a cavity in the second wafer for accommodating the light-emitting device.
16. The method of claim 12 , further comprising forming a bonding layer on the gasket, wherein the bond between the bonding layer and the bonding pad comprises a thermocompression bond.
17. The method of claim 16 , further comprising forming a barrier metal layer between at least one of (1) the bonding layer and the gasket, and (2) the bonding pad and the first wafer.
18. The method of claim 12 , wherein the bond is selected from the group consisting of a reaction bond and a solder bond.
19. The method of claim 12 , further comprising forming a treaded surface on the gasket.
20. The method of claim 12 , wherein the light-emitting device is selected from the group consisting of an edge-emitting laser and a vertical cavity surface-emitting laser (VCSEL).