Vacuum fixture and method for fabricating electronic assemblies

• US 5,546,654 A
• Filed: 08/29/1994
• Issued: 08/20/1996
• Est. Priority Date: 08/29/1994
• Status: Expired due to Fees

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Gorczyca, Thomas B., Wojnarowski, Robert J.
• Primary Examiner(s): VO, PETER DUNG BA
• Application Number:
  US08/297,076
• Time in Patent Office: 722 Days
• Field of Search: 29/743, 29/841, 29/852, 29/855, 29/856, 29/DIG. 44, 29/848, 279/3, 264/272.13-272.15, 414/737
• US Class Current: 29/841
• CPC Class Codes: H01L 2224/24137 the bodies being arranged next to each other, e.g. on a common substrate
• CPC Class Codes: H01L 2224/24227 the HDI interconnect not connecting to the same level of the item at which the semiconductor or solid-state body is mounted, e.g. the semiconductor or solid-state body being mounted in a cavity or on a protrusion of the item
• CPC Class Codes: H01L 2224/32225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/73267 Layer and HDI connectors
• CPC Class Codes: H01L 2924/15153 the die mounting substrate comprising a recess for hosting the device
• CPC Class Codes: H05K 1/182 associated with components mounted in the printed circuit board, e.g. insert mounted components [IMC]
• CPC Class Codes: H05K 3/284 for encapsulating mounted components H05K1/185 takes precedence
• CPC Class Codes: Y10S 29/044 Vacuum
• CPC Class Codes: Y10T 279/11 Vacuum
• CPC Class Codes: Y10T 29/49146 with encapsulating, e.g., potting, etc.
• CPC Class Codes: Y10T 29/49165 by forming conductive walled aperture in base
• CPC Class Codes: Y10T 29/53191 Means to apply vacuum directly to position or hold work part

Abstract

A method for fabricating an electronic assembly comprises attaching an insulative film to a frame and positioning at least one electronic component having a face with connections pads face down on the insulative film. The insulative film is positioned on a porous sheet supported by a vacuum fixture. The porous sheet and vacuum fixture are adapted so as to be capable of creating vacuum conditions for holding the insulative film with a substantially flat surface on the porous sheet. A vacuum is created within the vacuum chamber for flatly holding the insulative film on the porous sheet. A substrate is applied to the insulative film and the at least one electronic component. In one embodiment the substrate is applied by securing the insulative film in position with a mold form having at least one opening around the electronic component and adding substrate molding material at least partially around the component through the opening. In another embodiment the substrate is applied by providing a substrate having at least one well therein and positioning the insulative film over at least a portion of the substrate and the electronic component into the well.

Claims

1. A method for packaging an electronic component, comprising the steps of:

positioning at least one electronic component having a face with connection pads face down on an insulative film;

positioning the insulative film on a porous sheet supported by a vacuum fixture, the porous sheet and vacuum fixture for creating vacuum conditions for holding the insulative film with a substantially flat surface on the porous sheet;

creating a vacuum for flatly holding the insulative film on the porous sheet; and

applying a substrate to the insulative film and the at least one electronic component by

securing the insulative film in position with a mold form having at least one opening for holding substrate molding material to be added therein, the at least one opening positioned around the at least one electronic component; and

adding substrate molding material at least partially around the at least one component through the at least one opening; and

hardening the substrate molding material.

2. The method of claim 1, wherein the step of securing the insulative film includes placing a first portion of the mold form over the vacuum fixture, the first portion comprising a material that is nonadherent to the substrate molding material, and placing a second portion of the mold form over the first portion, the second portion comprising a clamping plate.

3. The method of claim 1, further including the step of providing a coating on at least a portion of the mold form, the coating comprising a material that is nonadherent to the substrate molding material.

4. The method of claim 1, further including the step of positioning a reinforcement plate over at least a portion of the substrate molding material prior to hardening the substrate molding material.

5. The method of claim 1, further including the step of applying an adhesive layer on the insulative film prior to positioning the at least one electronic component.

6. The method of claim 5 wherein the adhesive layer comprises an epoxy.

7. The method of claim 6, wherein the adhesive layer and the substrate molding material comprise similar materials.

8. The method of claim 1, further including the step of applying an adhesive to the face of the at least one electronic component prior to positioning the at least one electronic component.

9. The method of claim 1, further including the steps of, after hardening the substrate molding material,

removing the substrate molding material, the insulative film, and the at least one electronic component from the vacuum fixture,

forming a plurality of vias in the insulative film aligned with predetermined ones of the component pads, and

applying a pattern of electrical conductors extending through selected ones of said vias.

10. A method for packaging an electronic component, comprising the steps of:

positioning at least one electronic component having a face with connection pads face down on an insulative film;

positioning the insulative film on a porous sheet supported by a vacuum fixture, the porous sheet and vacuum fixture for creating vacuum conditions for holding the insulative film with a substantially flat surface on the porous sheet;

creating a vacuum for flatly holding the insulative film on the porous sheet; and

applying a substrate to the insulative film and the at least one electronic component by

providing a substrate having at least one well therein; and

positioning the insulative film on at least a portion of the substrate and the at least one electronic component into the at least one well while maintaining the vacuum.

11. The method of claim 10, further including the step of applying an adhesive to the at least one well prior to positioning the insulative film and the electronic component.

12. A method for packaging an electronic component comprising the steps of:

attaching an insulative film to a frame;

positioning the insulative film on a porous sheet supported by a vacuum fixture, the porous sheet and vacuum fixture for creating vacuum conditions for holding the insulative film with a substantially flat surface on the porous sheet;

providing a substrate having at least one well therein;

positioning at least one electronic component having a face with connection pads face up in the at least one well;

creating a vacuum for flatly holding the insulative film on the porous sheet; and

positioning the insulative film on the at least one electronic component and at least a portion of the substrate while maintaining the vacuum.

13. The method of claim 12, further including the step of applying an adhesive to the at least one well prior to positioning the at least one electronic component in the at least one well.

14. An apparatus for fabricating an electronic assembly, the apparatus comprising:

a porous sheet;

a vacuum fixture supporting the porous sheet, the porous sheet and vacuum fixture for creating vacuum conditions for holding an insulative film with a surface substantially flat on the porous sheet; and

a mold form positioned over one portion of the vacuum fixture, the mold form having at least one opening for the addition of substrate molding material.

15. The apparatus of claim 14, wherein the mold form comprises a clamping plate and an insert between the vacuum fixture and the clamping plate, the insert comprising a material that is nonadherent to the substrate molding material.

16. The apparatus of claim 15, wherein the insert has a thickness which is greater than the thickness of the substrate molding material.

17. The apparatus of claim 16, wherein the insert comprises polytetrafluoroethylene.

18. The apparatus of claim 14, further including a coating on at least a portion of the mold form, the coating comprising a material that is nonadherent to the substrate molding material.

19. The apparatus of claim 18, wherein the coating comprises polytetrafluoroethylene.

20. The apparatus of claim 14, further including at least one screw extending through the mold form and into the vacuum fixture for securing the mold form in position.

21. The apparatus of claim 14, further including a clamp for securing the mold form in position.

22. The apparatus of claim 14, wherein the porous sheet comprises a material selected from the group consisting of stainless steel, nickel molybdenum metal alloys, nickel copper metal alloys, and nickel chromium metal alloys.

23. The apparatus of claim 22, wherein the vacuum fixture and the support posts comprise a material selected from the group consisting of titanium, stainless steel, and nickel alloys.