Semiconductor packages utilizing leadframe panels with grooves in connecting bars

• US 9,355,995 B2
• Filed: 01/10/2014
• Issued: 05/31/2016
• Est. Priority Date: 12/13/2010
• Status: Active Grant

• Current Assignee: Infineon Technologies Americas Corp. (Infineon Technologies AG)
• Original Assignee: Infineon Technologies Americas Corp. (Infineon Technologies AG)
• Inventors: Fernando, Dean, Barbosa, Roel
• Primary Examiner(s): FERNANDES, ERROL V
• Application Number:
  US14/152,816
• Publication Number:
  US 20140127861A1
• Time in Patent Office: 872 Days
• Field of Search: 257/659, 257/660, 438/112, 438/111
• US Class Current: 1/1
• CPC Class Codes: H01L 2224/2929 with a principal constituent of the material being a polymer, e.g. polyester, phenolic based polymer, epoxy
• CPC Class Codes: H01L 2224/29339 Silver [Ag] as principal constituent
• CPC Class Codes: H01L 2224/32245 the item being metallic
• CPC Class Codes: H01L 2224/45015 being circular
• CPC Class Codes: H01L 2224/45144 Gold (Au) as principal constituent
• CPC Class Codes: H01L 2224/45147 Copper (Cu) 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 2224/49171 Fan-out arrangements
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 2224/83439 Silver [Ag] as principal constituent
• CPC Class Codes: H01L 2224/85005 being a temporary or sacrificial substrate
• CPC Class Codes: H01L 2224/97 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 23/3107 the device being completely enclosed
• CPC Class Codes: H01L 23/49513 having bonding material between chip and die pad
• CPC Class Codes: H01L 23/4952 the additional leads being a bump or a wire
• 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 23/49562 for devices being provided for in H01L29/00
• CPC Class Codes: H01L 23/49575 Assemblies of semiconductor devices on lead frames
• CPC Class Codes: H01L 24/29 : of an individual layer connector
• CPC Class Codes: H01L 24/32 : of an individual layer connector
• 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 24/49 : of a plurality of wire connectors
• CPC Class Codes: H01L 24/73 : Means for bonding being of different types provided for in two or more of groups H01L24/10, H01L24/18, H01L24/26, H01L24/34, H01L24/42, H01L24/50, H01L24/63, H01L24/71
• CPC Class Codes: H01L 24/85 : using a wire connector wire bonding in general B23K20/004
• 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 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 2924/01005 : Boron [B]
• CPC Class Codes: H01L 2924/01006 : Carbon [C]
• CPC Class Codes: H01L 2924/01029 : Copper [Cu]
• CPC Class Codes: H01L 2924/01033 : Arsenic [As]
• CPC Class Codes: H01L 2924/01047 : Silver [Ag]
• CPC Class Codes: H01L 2924/0105 : Tin [Sn]
• 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 2924/0781 : being an ohmic electrical conductor
• CPC Class Codes: H01L 2924/1305 : Bipolar Junction Transistor [BJT]
• CPC Class Codes: H01L 2924/13055 : Insulated gate bipolar transistor [IGBT]
• CPC Class Codes: H01L 2924/1306 : Field-effect transistor [FET]
• CPC Class Codes: H01L 2924/13064 : High Electron Mobility Transistor [HEMT, HFET [heterostructure FET], MODFET]
• CPC Class Codes: H01L 2924/13091 : Metal-Oxide-Semiconductor Field-Effect Transistor [MOSFET]
• 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 2924/20753 : larger or equal to 30 microns less than 40 microns
• CPC Class Codes: H01L 2924/20755 : larger or equal to 50 microns less than 60 microns
• CPC Class Codes: H01L 2924/3512 : Cracking

Abstract

According to an exemplary implementation, a method includes utilizing a leadframe panel comprising a plurality of leadframe modules, each of the plurality of leadframe modules having a leadframe pad. The leadframe panel has a plurality of bars each having a plurality of grooves, where the plurality of bars connect the plurality of leadframe modules. The method further includes attaching a device to the leadframe pad. The method also includes molding the leadframe panel while leaving a bottom of the leadframe pad exposed. Furthermore, the method includes sawing through the plurality of grooves of the plurality of bars to singulate the plurality of leadframe modules into separate packaged modules.

Claims

1. A method comprising:

utilizing a leadframe panel comprising a plurality of leadframe modules, each of said plurality of leadframe modules having a leadframe pad;

said leadframe panel having a plurality of bars each having a plurality of grooves, said plurality of bars connecting said plurality of leadframe modules;

attaching a device to said leadframe pad;

molding said leadframe panel while leaving a bottom of said leadframe pad exposed;

sawing through said plurality of grooves of said plurality of bars to singulate said plurality of leadframe modules into separate packaged modules, wherein each of said plurality of grooves is entirely discarded from each of said plurality of leadframe modules.

2. The method of claim 1, wherein each of said plurality of grooves adjoins one of said plurality of leadframe modules.

3. The method of claim 1, wherein each of said plurality of grooves adjoins a lead of one of said plurality of leadframe modules.

4. The method of claim 3, wherein said leadframe pad is structurally integral and continuous with said lead.

5. The method of claim 1, wherein said attaching said device to said leadframe pad comprises attaching a plurality of devices to said leadframe pad.

6. The method of claim 1, wherein said leadframe pad is of a plurality of leadframe pads and said attaching comprises attaching at least one device to each of said plurality of leadframe pads.

7. The method of claim 1, wherein said molding said leadframe panel results in molding material being situated in said plurality of grooves.

8. The method of claim 1, wherein said leadframe panel is a quad-flat no-leads (QFN) panel.

9. The method of claim 1, wherein said plurality of grooves are defined by a first thickness of said plurality of bars that is less than a second thickness of said plurality of bars.

10. A method comprising:

utilizing a leadframe panel comprising a plurality of leadframe modules, each of said plurality of leadframe modules having a leadframe pad;

forming a plurality of grooves in a plurality of bars, said plurality of bars connecting said plurality of leadframe modules to form said leadframe panel;

sawing through said plurality of grooves of said plurality of bars to singulate said plurality of leadframe modules into separate packaged modules, wherein each of said plurality of grooves is entirely discarded from each of said plurality of leadframe modules.

11. The method of claim 10, wherein each of said plurality of grooves adjoins one of said plurality of leadframe modules.

12. The method of claim 10, wherein each of said plurality of grooves adjoins a lead of one of said plurality of leadframe modules.

13. The method of claim 10, wherein said forming said plurality of grooves includes etching said plurality of bars.

14. The method of claim 10, wherein said forming said plurality of grooves includes etching said plurality of bars concurrently with etching said plurality of leadframe modules.

15. The method of claim 10 comprising molding, prior to the sawing, said leadframe panel while leaving a bottom of said leadframe pad exposed.

16. The method of claim 15, wherein said molding said leadframe panel results in molding material being situated in said plurality of grooves.

17. The method of claim 10, wherein said plurality of grooves are defined by a first thickness of said plurality of bars that is less than a second thickness of said plurality of bars.

18. The method of claim 17, wherein said plurality of bars are of said first thickness surrounding each of said leadframe modules.

19. The method of claim 10, comprising attaching a device to said leadframe pad.