Wafer level hermetic sealing method

• US 20050161757A1
• Filed: 03/24/2005
• Published: 07/28/2005
• Est. Priority Date: 02/03/2001
• Status: Abandoned Application

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Kim, Woon-bae, Cho, Chang-ho, Shin, Hyung-Jae
• Application Number:
  US11/087,552
• Publication Number:
  US 20050161757A1
• Time in Patent Office: Days
• US Class Current: 257/433
• CPC Class Codes: B81B 7/0077 Other packages not provided for in groups B81B7/0035 - B81B7/0074
• CPC Class Codes: B81C 1/00269 Bonding of solid lids or wafers to the substrate
• CPC Class Codes: B81C 1/00357 involving bonding one or several substrates on a non-temporary support, e.g. another substrate
• CPC Class Codes: B81C 2201/019 Bonding or gluing multiple substrate layers
• CPC Class Codes: H01L 21/50 Assembly of semiconductor devices using processes or apparatus not provided for in a single one of the subgroups H01L21/06 - H01L21/326, e.g. sealing of a cap to a base of a container
• CPC Class Codes: H01L 2224/05599 Material
• CPC Class Codes: H01L 2224/45015 being circular
• CPC Class Codes: H01L 2224/45099 Material
• CPC Class Codes: H01L 2224/48227 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/85399 Material
• CPC Class Codes: H01L 23/10 characterised by the material or arrangement of seals between parts, e.g. between cap and base of the container or between leads and walls of the container
• CPC Class Codes: H01L 24/48 of an individual wire connector
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/01079 Gold [Au]
• CPC Class Codes: H01L 2924/01322 Eutectic Alloys, i.e. obtained by a liquid transforming into two solid phases
• CPC Class Codes: H01L 2924/10253 Silicon [Si]
• CPC Class Codes: H01L 2924/12041 LED
• CPC Class Codes: H01L 2924/16235 Connecting to a semiconductor or solid-state bodies, i.e. cap-to-chip
• CPC Class Codes: H01L 2924/207 Diameter ranges

Abstract

A device that is hermetically sealed at a wafer level or a method of hermetically sealing a device, which is sensitive to high temperatures or affected by heating cycles. Semiconductor devices are formed on a wafer. A lid wafer is formed. Adhesives are formed in a predetermined position over the wafer and/or the lid wafer. The wafer and the lid wafer are sealed by the adhesives at the wafer level. The sealing may be performed at a low temperature using a solder to protect the devices sensitive to heat. The sealed devices are diced into individual chips. In the wafer level hermetic sealing method, a sawing operation is performed after the devices are sealed. Therefore, the overall processing time is reduced, devices are protected from the effects of moisture or particles, and devices having a moving structure, such as MEMS devices, are more easily handled.

Claims

1. An apparatus with a wafer level hermetic seal comprising:

a wafer;

a semiconductor device formed on a device side of the wafer;

a lid wafer with a front side facing the device side of the wafer; and

adhesives which adhere the device side of the wafer and the front side of the lid wafer in a predetermined position, wherein the adhesives seal the device in between the device side of the wafer and the front side of the lid wafer.

2. The apparatus with the wafer level hermetic seal of claim 1, wherein the adhesives are formed of one selected from the group consisting of In, Sn, Ag, Pb, Zn, Au, Bi, Sb, Cd, Ga and Cu, or an alloy of two or more of these metals.

3. The apparatus with the wafer level hermetic seal of claim 2, wherein the adhesives are formed of a material having a fusion point of 100˜

300°

C.

4. The apparatus with the wafer level hermetic seal of claim 2, wherein the adhesives are formed by deposition or sputtering.

5. The apparatus with the wafer level hermetic seal of claim 2, further comprising adhesive promoters formed over the device side of the wafer and/or the front side of the lid wafer to promote adhesion of the adhesives.

6. The apparatus with the wafer level hermetic seal of claim 5, wherein the adhesives and the adhesive promoters are disposed to align the wafer with the lid wafer.

7. The apparatus with the wafer level hermetic seal of claim 5, wherein the adhesive promoters are formed of metal or polymer.

8. The apparatus with the wafer level hermetic seal of claim 2, wherein electrical connectors are formed on the wafer to transceive an electrical signal.

9. The apparatus with the wafer level hermetic seal of claim 8, wherein the lid wafer comprises a through hole so that the electrical connectors are electrically connected to the outside via an interconnection line passing through the hole.

10. The apparatus with the wafer level hermetic seal of claim 2, wherein the adhesives have a preformed shape.

11. The apparatus with the wafer level hermetic seal of claim 2, wherein the lid wafer formed is a transparent material to exchange an optical signal.

12. The apparatus with the wafer level hermetic seal of claim 1, wherein the adhesives are formed of a material having a fusion point of 100˜

300°

C.

13. The apparatus with the wafer level hermetic seal of claim 1, further comprising adhesive promoters formed over the device side of the wafer and/or the front side of the lid wafer to promote adhesion of the adhesives.

14. The apparatus with the wafer level hermetic seal of claim 13, wherein the adhesives and the adhesive promoters are disposed to align the wafer with the lid wafer.

15. The apparatus with the wafer level hermetic seal of claim 13, wherein the adhesive promoters are formed of metal or polymer.

16. The apparatus with the wafer level hermetic seal of claim 1, wherein electrical connectors are formed on the wafer to transceive an electrical signal.

17. The apparatus with the wafer level hermetic seal of claim 16, wherein the lid wafer comprises a through hole so that the electrical connectors are electrically connected to the outside via an interconnection line passing through the hole.

18. The apparatus with the wafer level hermetic seal of claim 1, wherein the adhesives have a performed shape.

19. The apparatus with the wafer level hermetic seal of claim 1, wherein the lid wafer formed is a transparent material to exchange an optical signal.

20. The apparatus with the wafer level hermetic seal of claim 1, wherein the adhesives are formed of an organic sealant.