Patent Application

App. No. 10/985,312

Abstract

Claims (66)

1 . A method for manufacturing a semiconductor package, comprising:

providing a first wafer;

providing a second wafer having a device;

forming a separation layer on the first wafer;

forming a cap on the separation layer;

bonding the cap and the second wafer using a gasket; and

separating the first wafer from the cap to form the semiconductor package comprised of the cap, the gasket, and the second wafer.

2 . The method of claim 1 further comprising forming an adhesive layer on the first wafer.

3 . The method of claim 1 wherein forming the separation layer uses gold.

4 . The method of claim 1 wherein:

forming the cap uses photosensitive material; and

forming the gasket uses photosensitive material.

5 . The method of claim 1 wherein bonding the cap and the second wafer further comprises:

forming a gasket contact layer on the second wafer;

bonding the gasket and the gasket contact layer; and

separating the first wafer from the cap to form the semiconductor package comprised of cap, the gasket, the gasket contact layer, and the cap on the second wafer.

6 . The method of claim 1 wherein bonding the cap and the second wafer further comprises:

heating the gasket and the second wafer to about 18° C. to about 500° C.; and

pressing together the gasket and the second wafer with about 1 N to about 40 kN of force for about one minute to about two hours.

7 . The method of claim 1 wherein bonding the gasket and the gasket contact layer further comprises pressing together the gasket and the gasket contact layer in about 500 mbar pressure to about 999 mbar pressure.

8 . A method for manufacturing a semiconductor package, comprising:

providing a reusable first wafer;

providing a second wafer having devices and air bridge structures;

forming an adhesive layer on the reusable first wafer;

forming a separation layer on the adhesive layer;

forming a cap structure on the separation layer, the cap structure having a height greater than the height of the devices, by:

depositing a cap layer on the separation layer;

hardening the cap layer into a cap;

depositing a gasket layer on the cap; and

hardening the gasket layer into a gasket;

forming a photoresist defining a gasket contact region on the second wafer;

forming a gasket contact layer in the gasket contact region;

removing the photoresist;

bonding the cap structure and the gasket contact layer; and

separating the reusable first wafer from the cap structure to leave the cap structure attached to the gasket contact layer on the second wafer.

9 . The method of claim 8 wherein:

providing the reusable first wafer uses alumina, sapphire, silicon, or GaAs;

forming the cap structure further comprises forming the cap structure to enclose the devices and the air bridge structures; and

depositing the adhesive layer uses titanium.

10 . The method of claim 8 wherein depositing the separation layer uses gold.

11 . The method of claim 8 wherein:

depositing the cap layer uses polyimide or benzocyclobutene; and

depositing the gasket layer uses polyimide or benzocyclobutene.

12 . The method of claim 8 wherein forming the gasket contact layer uses titanium.

13 . The method of claim 8 wherein bonding the cap structure and the gasket contact layer further comprises:

heating the cap structure and the gasket contact layer to about 250° C.; and

pressing together the cap structure and the gasket contact layer with about 1500 N of force on 4 inch wafers for about ten minutes.

14 . The method of claim 8 wherein bonding the cap structure and the gasket contact layer further comprises pressing together the cap structure and the gasket contact layer with about 500 mbar pressure.

15 . A semiconductor package, comprising:

a wafer;

a device on the wafer;

a photosensitive gasket on the wafer; and

a photosensitive cap on the photosensitive gasket spaced from the device.

16 . The semiconductor package of claim 15 wherein:

the photosensitive cap further comprises a polyimide or benzocyclobutene cap; and

the photosensitive gasket further comprises a polyimide or benzocyclobutene gasket.

17 . The semiconductor package of claim 15 wherein the photosensitive gasket on the wafer further comprises:

a gasket contact layer on the wafer; and

the photosensitive gasket on the gasket contact layer.

18 . The semiconductor package of claim 15 wherein:

the photosensitive cap and the photosensitive gasket comprise a cap structure; and

the height of the cap structure is 1.5 to 2.5 times the height of the device.

19 . The semiconductor package of claim 15:

wherein the photosensitive cap and the photosensitive gasket comprise a cap structure; and

further comprising an inert gas under the cap structure.

20 . The semiconductor package of claim 15 wherein the cap is 10 to 50 μm thick.

Assignments (9)