Leadframe for semiconductor package

• US 8,102,037 B2
• Filed: 02/28/2011
• Issued: 01/24/2012
• Est. Priority Date: 03/27/2001
• Status: Expired due to Term

• Current Assignee: Amkor Technology Singapore Holding Pte., Ltd. (Amkor Technology Incorporated)
• Original Assignee: Amkor Technology Incorporated
• Inventors: Lee, Hyung Ju
• Primary Examiner(s): Luu, Chuong A.
• Application Number:
  US13/036,359
• Publication Number:
  US 20110140250A1
• Time in Patent Office: 330 Days
• Field of Search: 257/666, 257/670, 257/669, 257/712, 257/692, 257/693, 257/676, 257/672, 257/673, 257/674, 257/767, 257/748, 257/734, 257/735
• US Class Current: 257/666
• CPC Class Codes: H01L 2224/05599 Material
• CPC Class Codes: H01L 2224/32245 the item being metallic
• CPC Class Codes: H01L 2224/45015 being circular
• CPC Class Codes: H01L 2224/45124 Aluminium (Al) as principal constituent
• CPC Class Codes: H01L 2224/45144 Gold (Au) as principal constituent
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/48253 connecting the wire to a potential ring of the item
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 2224/85439 Silver (Ag) as principal constituent
• CPC Class Codes: H01L 2224/85444 Gold (Au) as principal constituent
• CPC Class Codes: H01L 2224/85455 Nickel (Ni) as principal constituent
• CPC Class Codes: H01L 2224/85464 Palladium (Pd) as principal constituent
• CPC Class Codes: H01L 2224/8547 Zirconium (Zr) as principal constituent
• CPC Class Codes: H01L 2224/92 Specific sequence of method steps
• CPC Class Codes: H01L 2224/92247 the second connecting process involving a wire connector
• CPC Class Codes: H01L 23/3107 the device being completely enclosed
• CPC Class Codes: H01L 23/49503 characterised by the die pad
• CPC Class Codes: H01L 23/49541 Geometry of the lead-frame
• CPC Class Codes: H01L 23/49548 Cross section geometry H01L23/49562 takes precedence
• CPC Class Codes: H01L 24/45 : of an individual wire connector
• 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 2924/00012 : 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 2924/01046 : Palladium [Pd]
• CPC Class Codes: H01L 2924/01078 : Platinum [Pt]
• CPC Class Codes: H01L 2924/01079 : Gold [Au]
• CPC Class Codes: H01L 2924/181 : Encapsulation
• CPC Class Codes: H01L 2924/18301 : being an anchoring portion, i.e. mechanical interlocking between the encapsulation resin and another package part
• CPC Class Codes: H01L 2924/207 : Diameter ranges

Abstract

A semiconductor package including a lead frame comprising a frame including both a ground ring and a chip mounting board located therein. Extending between the ground ring and the chip mounting board are a plurality of elongate slots or apertures. The ground ring is formed to include recesses within the bottom surface thereof which create regions of reduced thickness. A semiconductor chip bonded to the chip mounting board may be electrically connected to leads of the lead frame and to the ground ring via conductive wires. Those conductive wires extending to the ground ring are bonded to the top surface thereof at locations which are not aligned with the recesses within the bottom surface, i.e., those regions of the ground ring of maximum thickness.

Claims

1. A leadframe for use in a semiconductor package, the leadframe comprising:

a die pad;

a ground ring extending at least partially about the die pad and defining;

a generally planar first ground ring surface;

a generally planar second ground ring surface disposed in opposed relation to the first ground ring surface; and

at least one third ground ring surface formed between the first and second ground ring surfaces in opposed relation to the first ground ring surface; and

a plurality of leads extending at least partially about the ground ring in spaced relation thereto.

2. The leadframe of claim 1 wherein the die pad defines:

a generally planar first die pad surface;

a generally planar second die pad surface disposed in opposed relation to the first die pad surface; and

a third die pad surface formed between the first and second die pad surfaces in opposed relation to the first die pad surface and at least partially circumventing the second die pad surface.

3. The leadframe of claim 1 wherein each of the leads defines:

a generally planar first lead surface;

a generally planar second lead surface disposed in opposed relation to the first lead surface; and

a third lead surface formed between the first and second third lead surfaces in opposed relation to the first lead surface, the third lead surface being disposed closer to the ground ring than the second lead surface.

4. The leadframe of claim 1 further comprising at least two tie bars which are each connected to and extend between the die pad and the ground ring, and each define:

a generally planar first tie bar surface;

a generally planar second tie bar surface disposed in opposed relation to the first tie bar surface; and

a third tie bar surface formed between the first and second tie, bar wakes in opposed relation to the first tie bar surface.

5. The leadframe of claim 1 wherein the third ground ring surface defines at least two third ground ring surface portions which are separated by at least a portion of the second ground ring surface.

6. The leadframe of claim 1 wherein:

the die pad has a generally quadrangular configuration defining four peripheral edge segments;

the ground ring is segregated into four segments which extend along and are spaced from respective ones of the peripheral edge segments of the die pad; and

the leads are segregated into four sets which extend toward respective ones of the segments of the ground ring.

7. A leadframe for use in a semi conductor package, the leadframe comprising:

a die pad having at least one portion which is partially etched;

a ground ring extending at least partially about the die and baying portions which are partially etched and portions which are not partially etched; and

a plurality of leads extending at least partially about the ground ring in spaced relation thereto.

8. The leadframe of claim 7 wherein the die pad defines:

a generally planar first die pad surface;

a general planar second die pad surface disposed in opposed relation to the first die pad surface; and

an etched third die pad surface formed between the first and second the pad, surfaces in opposed relation to the first die pad surface and at least partially circumventing the second die pad surface.

9. The leadframe of claim 7 wherein each of the leads has at least one portion which is partially etched.

10. The leadframe of claim 9 wherein each of the leads defines:

a generally planar first lead surface;

a generally planar second lead surface disposed in opposed relation to the first lead surface; and

an etched third lead surface formed between the first and second third lead surfaces in opposed relation to the first lead surface, the third lead surface being disposed closer to the ground ring than the second lead surface.

11. The leadframe of claim 7 further comprising at least two tie bars which are each connected to and extend between the die gad and the ground ring.

12. The leadframe of claim 11 wherein each of the tie bars has at least one portion which is partially etched.

13. The leadframe of claim 12 wherein the tie bars each define:

a generally planar first tie bar surface;

a generally planar second tie bar surface disposed in opposed relation to the first tie bar surface; and

an etched third tie bar surface formed between the first and second tie bar surfaces in opposed relation to the first tie bar surface.

14. The leadframe of claim 7 wherein the ground ring is separated from the die pad by at least one elongate slot.

15. The leadframe of claim 7 wherein:

the die pad has a generally quadrangular configuration defining four peripheral edge segments;

the ground in is segregated into four segments which extend along and are spaced from respective ones of the peripheral edge segments of the die pad by elongate slots; and

the leads are segregated into four sets which extend toward respective ones of the segments of the ground ring.

16. The leadframe of claim 7 wherein the ground ring defines a third ground ring surface having at least two third ground ring surface portions which are disposed in opposed relation to a first ground ring surface, and are separated by at least a portion of a second ground ring surface which is also disposed in opposed relation to the first ground ring surface.

17. A leadframe for use in a semiconductor package, the leadframe comprising:

a die pad;

it ground ring extending at least partially about the die pad and having portions that are partially etched; and

a plurality of leads extending at least partially about the ground ring in spaced relation thereto.

18. The leadframe of claim 17 wherein the ground ring is separated from the die pad by at least one elongate slot.

19. The leadframe of claim 18 wherein the ground ring is separated from the die pad, by at least four elongate slots arranged in a generally quadrangular pattern.

20. The leadframe of claim 17 wherein the ground ring defines a third ground ring surface having at least two third ground ring surface portions which are disposed in opposed relation to a first ground ring surface, and are separated by at least a portion of a second ground ring surface which is also disposed in opposed relation to the first, ground ring surface.