Conformal shielding process using process gases

• US 8,720,051 B2
• Filed: 06/02/2011
• Issued: 05/13/2014
• Est. Priority Date: 06/27/2007
• Status: Active Grant

• Current Assignee: Qorvo US, Inc. (Qorvo, Inc.)
• Original Assignee: RF Micro Devices Incorporated (Qorvo, Inc.)
• Inventors: Leahy, Donald Joseph, Warren, Waite R. Jr., Parker, Stephen
• Primary Examiner(s): PHAN, THIEM D
• Application Number:
  US13/151,499
• Publication Number:
  US 20110235282A1
• Time in Patent Office: 1,076 Days
• Field of Search: 298/46, 295/921, 298/25, 298/29, 298/32, 298/50, 298/52, 174/250, 174/257, 174/267, 174/350, 174/377, 174/394, 257/433, 257/E23.114, 257/E23.125
• US Class Current: 29/846
• CPC Class Codes: H01L 23/552 Protection against radiation, e.g. light or electromagnetic waves
• CPC Class Codes: H01L 24/97 the devices being connected to a common substrate, e.g. interposer, said common substrate being separable into individual assemblies after connecting
• CPC Class Codes: H01L 25/0655 the devices being arranged next to each other
• CPC Class Codes: H01L 2924/01005 Boron [B]
• CPC Class Codes: H01L 2924/01006 Carbon [C]
• CPC Class Codes: H01L 2924/01013 Aluminum [Al]
• CPC Class Codes: H01L 2924/01016 Sulfur [S]
• CPC Class Codes: H01L 2924/01018 Argon [Ar]
• CPC Class Codes: H01L 2924/01029 Copper [Cu]
• CPC Class Codes: H01L 2924/0103 Zinc [Zn]
• CPC Class Codes: H01L 2924/01033 Arsenic [As]
• CPC Class Codes: H01L 2924/01046 Palladium [Pd]
• CPC Class Codes: H01L 2924/01047 Silver [Ag]
• CPC Class Codes: H01L 2924/01078 Platinum [Pt]
• CPC Class Codes: H01L 2924/01079 Gold [Au]
• CPC Class Codes: H01L 2924/01082 Lead [Pb]
• CPC Class Codes: H01L 2924/014 Solder alloys
• CPC Class Codes: H01L 2924/12041 LED
• CPC Class Codes: H01L 2924/14 Integrated circuits
• CPC Class Codes: H01L 2924/1815 Shape
• CPC Class Codes: H01L 2924/3025 : Electromagnetic shielding
• CPC Class Codes: H05K 1/0218 : by printed shielding conductors, ground planes or power plane H05K1/0236 takes precedence
• CPC Class Codes: H05K 2203/0723 : Electroplating, e.g. finish plating
• CPC Class Codes: H05K 3/0052 : Depaneling, i.e. dividing a panel into circuit boards; Working of the edges of circuit boards
• CPC Class Codes: H05K 3/181 : by electroless plating adhesives therefor H05K3/387
• CPC Class Codes: H05K 3/284 : for encapsulating mounted components H05K1/185 takes precedence
• CPC Class Codes: Y10T 29/49 : Method of mechanical manufacture
• CPC Class Codes: Y10T 29/49002 : Electrical device making
• CPC Class Codes: Y10T 29/49117 : Conductor or circuit manufacturing
• CPC Class Codes: Y10T 29/49124 : On flat or curved insulated base, e.g., printed circuit, etc.
• CPC Class Codes: Y10T 29/49126 : Assembling bases
• CPC Class Codes: Y10T 29/49128 : Assembling formed circuit to base
• CPC Class Codes: Y10T 29/4913 : Assembling to base an electrical component, e.g., capacitor, etc.
• CPC Class Codes: Y10T 29/49131 : by utilizing optical sighting device
• CPC Class Codes: Y10T 29/49144 : by metal fusion
• CPC Class Codes: Y10T 29/49146 : with encapsulating, e.g., potting, etc.
• CPC Class Codes: Y10T 29/49153 : with shaping or forcing terminal into base aperture
• CPC Class Codes: Y10T 29/49155 : Manufacturing circuit on or in base
• CPC Class Codes: Y10T 29/49204 : Contact or terminal manufacturing
• CPC Class Codes: Y10T 29/49789 : Obtaining plural product pieces from unitary workpiece

Abstract

In one embodiment, a meta-module having circuitry for two or more modules is formed on a substrate, which is preferably a laminated substrate. The circuitry for the different modules is initially formed on the single meta-module. Each module will have one or more component areas in which the circuitry is formed. A metallic structure is formed on or in the substrate for each component area to be shielded. A single body, such as an overmold body, is then formed over all of the modules on the meta-module. At least a portion of the metallic structure for each component area to be shielded is then exposed through the body by a cutting, drilling, or like operation. Next, an electromagnetic shield material is applied to the exterior surface of the body of each of the component areas to be shielded and in contact with the exposed portion of the metallic structures.

Claims

1. A method of manufacturing a module comprising:

providing an electronic meta-module comprising a substrate, a plurality of component areas on a top surface of the substrate for a plurality of modules, a plurality of electrical contacts on a bottom surface of the substrate, and a body formed from an overmold material that covers the plurality of component areas, wherein certain component areas of the plurality of component areas are associated with metallic structures that are covered by the body, and a seal structure on the bottom surface of the substrate, wherein the seal structure is configured to provide a seal between the bottom surface of the substrate and a top surface of a carrier media on which the substrate is carried during processing;

exposing at least a portion of the metallic structures associated with the certain component areas through the body to provide a plurality of exposed metallic structures;

exposing exterior surfaces of the body to a reactive process gas to clean the exterior surfaces of the body; and

applying an electromagnetic shield material over at least portions of the exterior surfaces of the body for each of the certain component areas and on the plurality of exposed metallic structures to form electromagnetic shields over the certain component areas.

2. The method of claim 1 wherein the reactive process gas removes contaminants on the exterior surfaces of the body.

3. The method of claim 1 wherein the reactive process gas comprises one of a group consisting of Argon, Oxygen, Nitrogen, Hydrogen, Carbon Tetrafluoride, Sulfur Hexafluoride, and Nitrogen Tri-fluoride.

4. The method of claim 1 wherein exposing the exterior surfaces of the body to the reactive process gas to clean the exterior surfaces of the body comprises using a plasma-based cleaning process to clean the exterior surfaces of the body.

5. The method of claim 1 further comprising roughening the exterior surfaces of the body prior to applying the electromagnetic shield material.

6. The method of claim 1 further comprising separating the plurality of modules of the electronic meta-module from each other, wherein each module comprises at least one of the certain component areas having one of the electromagnetic shields.

7. The method of claim 1 further comprising separating the plurality of modules of the electronic meta-module from each other, wherein each module comprises a plurality of the certain component areas having the electromagnetic shields.

8. The method of claim 1 wherein applying the electromagnetic shield material comprises spraying a conductive material over the at least portions of the exterior surfaces of the body and on the plurality of exposed metallic structures.

9. The method of claim 1 wherein applying the electromagnetic shield material comprises plating at least one conductive material over the at least portions of the exterior surfaces of the body and on the plurality of exposed metallic structures.

10. The method of claim 9 wherein plating the at least one conductive material over the at least portions of the exterior surfaces of the body and on the plurality of exposed metallic structures comprises plating a first layer with an electroless plating process and plating a second layer with an electrolytic plating process.

11. The method of claim 1 wherein providing the electronic meta-module comprising the substrate, the plurality of component areas on the top surface of the substrate for the plurality of modules, the plurality of electrical contacts on the bottom surface of the substrate, and the body formed from the overmold material that covers the plurality of component areas comprises:

uniformly covering the plurality of component areas for the plurality of modules with the overmold material to form the body, such that the body is initially a single, continuous element that covers all of the plurality of component areas prior to exposing the plurality of exposed metallic structures.

12. The method of claim 11 wherein uniformly covering the plurality of component areas for the plurality of modules with the overmold material to form the body, such that the body is initially the single, continuous element that covers the all of the plurality of component areas prior to exposing the plurality of exposed metallic structures comprises:

using an overmolding process to form the body with the overmold material.

13. The method of claim 11 wherein the overmold material is a dielectric material.

14. The method of claim 1 wherein the metallic structures are located on the top surface of the substrate.

15. The method of claim 1 wherein the metallic structures associated with a certain component area of the certain component areas extend substantially about a periphery of the certain component area.

16. The method of claim 15 wherein each metallic structure of the metallic structures comprises a continuous metal trace on the top surface of the substrate.

17. The method of claim 15 wherein each of the metallic structures comprises a discontinuous metal trace on the top surface of the substrate.

18. The method of claim 15 wherein each of the metallic structures comprises a series of metallic structures on the top surface of the substrate.

19. The method of claim 1 wherein exposing the at least a portion of the metallic structures associated with the certain component areas through the body to provide the plurality of exposed metallic structures comprises cutting through the body at least one of:

to surfaces of the plurality of exposed metallic structures; and

into the surfaces of the plurality of exposed metallic structures.

20. The method of claim 1 wherein exposing the at least a portion of the metallic structures associated with the certain component areas through the body comprises drilling through the body at least one of:

to surfaces of the plurality of exposed metallic structures; and

into the surfaces of the plurality of exposed metallic structures.

21. The method of claim 1 wherein the metallic structures are part of a metallic grid that is formed on the substrate and defines the certain component areas for the plurality of modules.

22. The method of claim 1 wherein the overmold material is a dielectric material.

23. The method of claim 1 wherein applying the electromagnetic shield material over the at least portions of the exterior surfaces of the body for each of the certain component areas and on the plurality of exposed metallic structures to form the electromagnetic shields over the certain component areas comprises:

depositing a seed layer of conductive material on top of the body of each sub-module and in contact with the plurality of exposed metallic structures;

generating a second layer of conductive material on top of the seed layer through an electrolytic plating process; and

generating a third layer of material on top of the second layer through a second electrolytic plating process.

24. The method of claim 23 wherein the seed layer of conductive material is Copper (Cu).

25. The method of claim 24 wherein the second layer of conductive material is formed from Copper (Cu).

26. The method of claim 25 wherein the third layer of material is formed from Nickel (Ni).

27. The method of claim 23 wherein the seed layer of conductive material is deposited using a first electroless plating process.

28. The method of claim 27 wherein the second layer of conductive material is deposited using an electrolytic plating process.

29. The method of claim 28 wherein the third layer of material is deposited using a second electrolytic plating process.