METHOD AND APPARATUS FOR PREVENTION OF SOLDER CORROSION UTILIZING FORCED AIR

• US 20080067651A1
• Filed: 09/15/2006
• Published: 03/20/2008
• Est. Priority Date: 09/15/2006
• Status: Abandoned Application

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Singh, Prabjit, Torok, John G., Loparco, John J., Goth, Gary F., Kostenko, William P.
• Application Number:
  US11/532,396
• Publication Number:
  US 20080067651A1
• Time in Patent Office: Days
• US Class Current: 257/678
• CPC Class Codes: H01L 2224/0401 Bonding areas specifically adapted for bump connectors, e.g. under bump metallisation [UBM]
• CPC Class Codes: H01L 2224/73253 Bump and layer connectors
• CPC Class Codes: H01L 23/041 the container being a hollow construction having no base used as a mounting for the semiconductor body
• CPC Class Codes: H01L 23/053 the container being a hollow construction and having an insulating or insulated base as a mounting for the semiconductor body
• CPC Class Codes: H01L 23/562 Protection against mechanical damage H01L23/02, H01L23/28 take precedence
• CPC Class Codes: H01L 24/16 of an individual bump connector
• CPC Class Codes: H01L 24/32 of an individual layer connector
• CPC Class Codes: H01L 25/0655 the devices being arranged next to each other
• CPC Class Codes: H01L 2924/00011 Not relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• 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 2924/14 Integrated circuits
• CPC Class Codes: H01L 2924/1433 Application-specific integrated circuit [ASIC]
• CPC Class Codes: H01L 2924/15311 being a ball array, e.g. BGA
• CPC Class Codes: H01L 2924/16152 Cap comprising a cavity for hosting the device, e.g. U-shaped cap

Abstract

Disclosed is a multi-chip module with solder corrosion prevention including one or more chips connected to a substrate by soldering, the substrate situated on a printed circuit board. The multi-chip module also includes a molecular sieve desiccant chamber containing a quantity of molecular sieve desiccant and a first cover to contain the one or more chips, the substrate, and the molecular sieve desiccant, the first cover having a seal to the printed circuit board. The molecular sieve desiccant chamber is connected to the first cover via a first fluid pathway and a second fluid pathway.

Claims

1. A multi-chip module with solder corrosion prevention comprising:

one or more chips connected to a substrate by soldering, the substrate disposed on a printed circuit board;

a molecular sieve desiccant chamber, the molecular sieve desiccant chamber including a quantity of molecular sieve desiccant;

a first cover to contain the one or more chips and the substrate, the first cover having a seal to the printed circuit board;

a first fluid pathway extending from the first cover to the molecular sieve desiccant chamber; and

a second fluid pathway extending from the molecular sieve desiccant chamber to the first cover.

2. The multi-chip module of claim 1 further comprising a fluid pump disposed in the second port.

3. The multi-chip module of claim 1 further comprising a heat exchanger disposed in the second port.

4. The multi-chip module of claim 1 further comprising a second cover sealing a second side of the printed circuit board opposite a first side of the printed circuit board on which the substrate is disposed.

5. The multi-chip module of claim 1 wherein the first cover includes a seal for sealing to the printed circuit board.

6. The multi-chip module of claim 5 wherein the seal for sealing to the printed circuit board is formed of butyl rubber.

7. The multi-chip module of claim 1 wherein the multi-chip module connects to the printed circuit board by a land grid array.

8. The multi-chip module of claim 1 wherein the soldering is a controlled collapse chip connection.

9. A method of preventing corrosion of multi-chip-module solder connections, comprising:

sealing the multi-chip-module in a first chamber;

connecting the first chamber to a second chamber containing a molecular sieve desiccant with a first fluid pathway port and a second fluid pathway;

urging movement of a fluid in a serial motion from the first chamber through the first port to the second chamber and through the second port back to the first chamber; and

adsorbing moisture from the fluid with the molecular sieve desiccant in the second chamber.

10. The method of claim 9 further comprising adsorbing carbon dioxide from the fluid with the molecular sieve desiccant in the second chamber.

11. The method of claim 9, further comprising:

positioning a first port connection to the first chamber above a second port connection to the first chamber; and

cooling the fluid in the second port, thereby urging the serial motion of the fluid by convection.

12. The method of claim 9, further comprising urging the fluid with a fluid pump.

13. The method of claim 11 further comprising cooling the fluid in the second port with a heat exchanger.