Low-cost package for electronic components

• US 5,428,188 A
• Filed: 01/18/1994
• Issued: 06/27/1995
• Est. Priority Date: 10/09/1992
• Status: Expired due to Fees

• Current Assignee: U.S. Terminals, Inc.
• Original Assignee: U.S. Terminals, Inc.
• Inventors: Dozier, Hilliard S.
• Primary Examiner(s): Ledynh, Bot L.
• Application Number:
  US08/183,985
• Time in Patent Office: 525 Days
• Field of Search: 174/52.2, 174/52.4, 257/671-672, 257/676, 257/687, 257/692, 257/694, 257/787, 361/728, 361/730, 361/733
• US Class Current: 174/527
• CPC Class Codes: H01L 2224/16245 the item being metallic
• CPC Class Codes: H01L 2224/45144 Gold (Au) as principal constituent
• CPC Class Codes: H01L 23/04 characterised by the shape of the container or parts, e.g. caps, walls
• CPC Class Codes: H01L 23/047 the other leads being parallel to the base
• CPC Class Codes: H01L 23/49562 for devices being provided for in H01L29/00
• 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 2924/01079 Gold [Au]

Abstract

A low cost package uses non-ceramic materials to environmentally seal an air chamber for an electronic component. The package includes a base formed by a plurality of essentially flat terminals molded in a polyphenylene sulfide resin so as to provide a planar surface for surface mounting to a circuit board. A component placement area on the base receives a cap which covers and seals the area from contaminants.

Claims

1. A package for environmentally sealing an electronic component, comprising:

a. a base member, said base member including;

i. a plurality of electrical terminals arranged in fixed predetermined spaced relationship to each other, each of the terminals having a bottom surface having a major portion that is substantially coplanar with major portions of the bottom surfaces of the other of the plurality of terminals, the peripheral edge of selected portions of each of the terminals having a top portion that extends outwardly beyond the extension of the corresponding bottom surface of the terminal; and

ii. plastic insulating material molded to and encasing each of said terminals, the plastic material covering substantially all of the top surfaces of the terminals except for predetermined recessed areas in which the terminals are exposed,the bottom surface of the plastic material being disposed in the space beneath thee selected portions of the peripheral edges of the terminals and forming a surface that is substantially coplanar with the bottom surfaces of the terminals, the top surface of the plastic material including a raised wall defining a component placement area, the recessed areas being disposed in the component placement area and being adapted for positioning an electronic component on at least one of the terminals and for interconnecting the electronic component with the other terminals; and

b. a cap, said cap being seatable upon the top surface of the plastic material to sealingly enclose an air chamber in the component placement area surrounded by the raised wall.

2. A package as recited in claim 1 wherein the peripheral edge of selected portions of each of the terminals are formed by coining the selected portions from the bottom side.

3. A package as recited in claim 1 further including a plurality of contoured plastic reinforcing sections extending from the raised wall to the component placement area.

4. A base as recited in claim 3 wherein each of the terminals have a thickness that is substantially less than either of its length or width.

5. A package as recited in claim 3 wherein at least one of the flanges has an ear that protrudes outwardly into the plastic material for inhibiting withdrawal of the terminal from the molded plastic material.

6. A package as recited in claim 1 wherein the recessed bonding areas have chamfered openings about their peripheries.

7. A package as recited in claim 6 wherein the flanges have a thickness of approximately one third the thickness of the terminals.

8. A package as recited in claim 1 wherein the top portion of the peripheral edge of selected portions of each of the terminals has a thickness approximately equal to one-half the thickness of the terminal.

9. A package as recited in claim 1 wherein the top surfaces of each of the terminals are substantially coplanar.

10. A base as recited in claim 1 wherein the top surfaces of the terminals are substantially coplanar with each other.

11. A package as recited in claim 10 wherein the cap is dimensioned and configured to contact the base member about the top and side portions of the raised rib, and bout the outer periphery of the rib.

12. A base as recited in claim 11 wherein the flanges have a thickness of approximately one third the thickness of the terminals.

13. A package as recited in claim 11 wherein at least one of the flanges has an ear that protrudes outwardly into the plastic material for inhibiting withdrawal of the terminal from the molded plastic material.

14. A package as recited in claim 1 wherein the plastic material is polyphenylene sulfide.

15. A package as recited in claim 14 wherein the adhesive is a two-part epoxy adhesive consisting of approximately twelve parts by weight of an epoxy polymer to eight parts by weight of mica to five parts by weight of an anhydride.

16. A package as recited in claim 1 wherein the flanges are formed by coining selected peripheral areas of the terminals.

17. A package as recited in claim 1 wherein the cap is dimensioned and configured to contact the base member at selected contacting seating surfaces, and the contacting seating surfaces of the base member and the cap are roughened to increase the area of the contacting surfaces.

18. A package as recited in claim 1 wherein the cap is secured to the base member with an adhesive.

19. A base as recited in claim 18 wherein top surfaces of the terminals are substantially coplanar with each other.

20. A base as recited in claim 18 wherein the plastic material is polyphenylene sulfide.

21. A package as recited in claim 1 wherein the component placement area defined by the raised ribs has a square configuration.

22. A package as recited in claim 1 wherein the base member includes at least three terminals.

23. A package for environmentally sealing an electronic component, comprising:

a. a base member, said base member including;

i. a plurality of electrical terminals arranged in fixed predetermined spaced relationship to each other, each of the terminals having a bottom surface that is substantially coplanar with the bottom surfaces of the other of the plurality of terminals, at least one of said terminals having a flange on a portion of its periphery extending between planes formed by said bottom surface and a top surface of said terminal, the flange having a thickness that is substantially less than the thickness of the remaining portions of the terminal; and

ii. plastic insulating material molded to each of said terminals and encasing said flange, the bottom surface of the plastic material being coplanar with the bottom surfaces of the terminals, the top surface of the plastic material including a raised rib defining a component placement area having surface exposure to a plurality of the terminals for positioning an electronic component, the flange being positioned subjacent to the component placement area, whereby the bottom surface of the base member is substantially coplanar and adapted for surface mounting to a circuit board; and

b. a cap, said cap being seated upon the top surface of the plastic material to sealingly enclose an air chamber in the component placement area surrounded by the raised rib.

24. A package for environmentally sealing an electronic component, comprising:

a. a base member, said base member including;

i. a plurality of electrical terminals arranged in fixed predetermined spaced relationship to each other, each of the terminals having substantially planar top and bottom surfaces that are coplanar with the respective top and bottom surfaces of the other of the plurality of terminals, each of said terminals having a thickness that is substantially less than either its length or width and a flange on a portion of its periphery extending between planes formed by said top and bottom surfaces, the flanges having a thickness that is substantially less than the remaining portions of the terminals; and

ii. plastic insulating material molded to each of said terminals and encasing said flanges, the bottom surface of the plastic material being coplanar with the bottom surfaces of the terminals, the top surface of the plastic material including a raised rib defining a component placement area for positioning an electronic component, whereby the bottom surface of the base is substantially coplanar and adapted for surface mounting to a circuit board; and

b. a cap, the lower surface of said cap having a configuration that is complimentary to the configuration of the top surface of the base member, said cap being seated upon the top surface of the base member to sealingly enclose an air chamber in the component placement area defined by the raised rib.

25. A base member adapted for sealing engagement with a cap for environmentally packaging an electronic component, comprising:

a. a plurality of electrical terminals arranged in fixed predetermined spaced relationship to each other, the terminals having substantially planar bottom surfaces that are coplanar with each other, each of said terminals having a flange on a portion of its periphery, extending between planes formed by said bottom surfaces and top surfaces of said terminals, the flanges having a thickness that is substantially less than the remaining portions of the terminals; and

b. plastic insulating material molded to each of said terminals and encasing said flanges, the top surface of the plastic material defining a component placement area for positioning an electronic component and further including a raised rib, said raised rib surrounding the component placement area, the bottom surface of the plastic material being coplanar with the bottom surfaces of the terminals whereby the bottom surface of the base is substantially coplanar and adapted for surface mounting to a circuit board.

26. A package for environmentally sealing one or more electronic components, comprising:

a. a base member, said base member including;

i. a plurality of electrical terminals arranged in fixed predetermined spaced relationship to each other, each of the terminals having top and bottom surfaces with major portions that are substantially coplanar with major portions of the respective top and bottom surfaces of the other of the plurality of terminals, the peripheral edge of at least one of the terminals having an outwardly extending portion that is in the space defined by the planes of the major portions of the top and bottom surfaces, the flange having a thickness that is substantially less than the remaining portions of the terminal; and

ii. plastic insulating material molded to and encasing said flange, the bottom surface of the plastic material being coplanar with the bottom surface of said terminal, and including a raised rib defining a component placement area having surface exposure to a plurality of the terminals for positioning an electronic component, whereby the bottom surface of the base member is substantially coplanar and adapted for surface mounting to a circuit board; and

b. a cap, said cap seated upon the top surface of the plastic material to sealingly enclose an air chamber in the component placement area surrounded by the raised rib.

27. A package as recited in the claim 26 wherein the flange is positioned proximal to the component placement area.

28. A package for environmentally sealing one or more electronic components, comprising:

a. a base member, said base member including;

i. a plurality of electrical terminals arranged in fixed predetermined spaced relationship to each other, each of the terminals having a bottom surface with a major portion that is substantially coplanar with a major portion of the bottom surfaces of the other of the plurality of terminals, at least one of the terminals having a flange on a portion of its periphery that extends outwardly in a direction generally parallel to the plane of the bottom surfaces of the terminals, the flange having a thickness that is substantially less than the remaining portions of the terminal; and

ii. plastic insulating material molded to and encasing said flange, the bottom surface of the plastic material being coplanar with the bottom surfaces of the terminals, the top surface of the plastic material including a raised rib defining a component placement area having surface exposure to a plurality of the terminals for positioning one or more electronic components, whereby the bottom surface of the base member is substantially coplanar and adapted for surface mounting to a circuit board; and

b. a cap, said cap seated upon the top surface of the plastic material to sealingly enclose an air chamber in the component placement area surrounded by the raised rib.