Electronic devices and a sheet strip for packaging bonding wire connections of electronic devices and method for producing them

• US 6,525,416 B2
• Filed: 10/04/2001
• Issued: 02/25/2003
• Est. Priority Date: 10/04/2000
• Status: Expired due to Term

• Current Assignee: Polaris Innovations Limited (Wi-LAN Inc.)
• Original Assignee: Infineon Technologies AG
• Inventors: Reiss, Martin, Hauser, Christian, Winderl, Johann
• Primary Examiner(s): Paladini; Albert W.
• Assistant Examiner(s): Zarneke; David A.
• Application Number:
  US09/970,979
• Publication Number:
  US 20020041017A1
• Time in Patent Office: 509 Days
• Field of Search: 257/678,687,704,710,730,731,787
• US Class Current: 257/687
• CPC Class Codes: B29C 33/06 using radiation , e.g. electro-magnetic waves, induction heating
• CPC Class Codes: H01L 2224/05599 Material
• CPC Class Codes: H01L 2224/32225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/45015 being circular
• CPC Class Codes: H01L 2224/45099 Material
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/4824 Connecting between the body and an opposite side of the item with respect to the body
• CPC Class Codes: H01L 2224/48472 the other connecting portion not on the bonding area also being a wedge bond, i.e. wedge-to-wedge
• CPC Class Codes: H01L 2224/73215 Layer and wire connectors
• CPC Class Codes: H01L 2224/85399 Material
• CPC Class Codes: H01L 23/057 the leads being parallel to the base
• CPC Class Codes: H01L 23/08 the material being an electrical insulator, e.g. glass
• CPC Class Codes: H01L 23/3121 a substrate forming part of the encapsulation
• 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 2924/01068 Erbium [Er]
• CPC Class Codes: H01L 2924/01077 Iridium [Ir]
• CPC Class Codes: H01L 2924/12042 LASER
• CPC Class Codes: H01L 2924/181 Encapsulation
• CPC Class Codes: H01L 2924/207 : Diameter ranges
• CPC Class Codes: H01L 2924/3025 : Electromagnetic shielding

Abstract

An electronic device is described that has a sheet strip for packaging bonding wire connections of the electronic device and a method for producing it. To that end, the sheet strip, has at least two preformed, opposite edge regions which cover the edge regions of the bonding channel in an overlapping manner. Furthermore, the sheet strip has a preformed central region situated between the edge regions, which central region has a bulge and thickened portion and has two convexly curved contour lines in cross section.

Claims

1. An electronic device, comprising:

a chip having an active surface and contact areas;

a laminate disposed on said active area of said chip and having a bonding channel with edge regions formed therein, said laminate further having contact connection areas, conductor tracks and soldering contact areas and surrounds said bonding channel, said contact areas of said chip disposed along said bonding channel;

bonding wires connecting said contact areas of said chip to said contact connection areas of said laminate; and

a flowable sheet formed of a potting compound surrounding said bonding wires in said bonding channel, said flowable sheet having mutually opposite edge regions overlapping said edge regions of said bonding channel, said flowable sheet selected from the group consisting of a flowable sheet strip and flowable sheet patches, said flowable sheet containing a preformed central region extending between said mutually opposite edge regions and having a bulge and a thickened portion, said preformed central region further having two convexly curved contour lines in cross section.

2. The device according to claim 1, wherein said flowable sheet strip is a composite strip including:

a base sheet strip having at least two preformed, mutually opposite edge regions covering said edge regions of said bonding channel in an overlapping manner, and a preformed central region extending between said opposite edge regions and having a bulge and a thickened portion, said central region further having two convexly curved contour lines in cross-section; and

a covering strip of uniform thickness disposed on said base sheet strip.

3. The device according to claim 2, wherein said covering strip is formed of a shrink material and has edge regions adhesively fixed on said edge regions of said bonding channel.

4. The device according to claim 2, wherein said thickened portion in said central region of said base sheet strip is matched to a volume of said bonding channel.

5. The device according to claim 2, wherein said opposite edge regions of said base sheet strip overlapping said edge regions of said bonding channel are connected gas-tightly to said edge regions of said bonding channel.

6. The device according to claim 1, wherein a flowability of said flowable sheet strip commences at a threshold temperature.

7. The device according to claim 2, wherein a ratio between a maximum thickness of said central region of said base sheet strip to a thickness of said opposite edge regions of said base sheet strip is 3:

1.

8. The device according to claim 2, wherein a ratio between a maximum thickness of said a central region of said base sheet strip to a thickness of said opposite edge regions of said base sheet strip is 5:

1.

9. The device according to claim 2, wherein an upper one of said two convexly curved contour lines of said base sheet strip has a convex curvature in said central region, the convex curvature is higher than an elevation of said bonding wires connected to said contact connection areas extending beyond said bonding channel.

10. The device according to claim 1, wherein said laminate contains a porous plastic.

11. The device according to claim 1, wherein said laminate is constructed from a gas-tight plastic.

12. The device according to claim 1, wherein said bonding channel has a channel bottom and said contact areas of said chip are disposed at said channel bottom.

13. The device according to claim 1, wherein said laminate has a surface facing said flowable sheet strip and said contact connection areas, said conductor tracks and said soldering contact areas are disposed on said surface facing said flowable sheet strip.

14. The device according to claim 13, including a soldering mask layer disposed on said surface of said laminate facing said flowable sheet strip, said soldering mask layer partly covering said conductor tracks and leaving uncovered both said contact connection areas for bonding and said soldering contact areas for application of one of soldering bumps and soldering balls.

15. The device according to claim 1, including bonding pads having edge regions disposed in said bonding channel and said flowable sheet strip overlaps said edge regions of said bonding pads, said contact areas of said chip disposed one of along said bonding pads and in said bonding pads.