Lead frame and method

• US 4,480,150 A
• Filed: 07/12/1982
• Issued: 10/30/1984
• Est. Priority Date: 07/12/1982
• Status: Expired due to Term

• Current Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Lawson, John M., Jones, Raymond N., Keil, O'Dell F.
• Primary Examiner(s): Gonzales, John F.
• Assistant Examiner(s): Tone, D. A.
• Application Number:
  US06/397,662
• Time in Patent Office: 841 Days
• Field of Search: 174/52 FP, 357/70, 361/421, 29/423, 29/430, 29/574, 29/827, 428/571, 206/330
• US Class Current: 174/529
• CPC Class Codes: H01L 21/6835 using temporarily an auxiliary support
• CPC Class Codes: H01L 2221/68331 of passive members, e.g. die mounting 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 23/49503 characterised by the die pad
• CPC Class Codes: H01L 2924/01027 Cobalt [Co]
• CPC Class Codes: H01L 2924/01033 Arsenic [As]
• CPC Class Codes: H01L 2924/01082 Lead [Pb]
• CPC Class Codes: Y10T 156/1052 with cutting, punching, tearing or severing
• CPC Class Codes: Y10T 29/49121 Beam lead frame or beam lead device
• CPC Class Codes: Y10T 29/4981 Utilizing transitory attached element or associated separate material

Abstract

A lead frame and method in which an adhesive tape strip such as Mylar is rolled or pressed along the undersurface of the lead frame to contact the lead frame and bonding pad undersurfaces. Upon removal of the tags retaining the individual circuit elements to the lead frame, the parts are maintained in their existing orientation and position by the tape strip in conjunction with the lead frame. The circuit elements may then be handled as a unit by means of the lead frame/tape strip combination in subsequent testing, marking, lead bending or other handling operations.

Claims

1. A lead frame comprising:

at least one runner presenting parallel opposite upper and lower faces thereof;

a plurality of bonding pads detachably affixed to said runner, said bonding pads presenting opposite upper and lower surfaces thereof; and

a tape strip adhesively and removably secured to said runner lower face and bonding pad lower surfaces.

2. The lead frame of claim 1 wherein said lead frame further comprises a die bonded to said bonding pad upper surfaces.

3. The lead frame of claim 1 wherein said tape strip comprises a polyethylene terephthalate tape.

4. A method for handling a plurality of components comprising the steps of:

providing a lead frame having at least one runner presenting parallel opposite upper and lower faces thereof;

detachably furnishing a plurality of bonding pads pre-affixed to said runner, said bonding pads presenting opposite upper and lower surfaces thereof; and

adhesively and removably securing a tape strip to said runner lower face and said bonding pad lower surfaces.

5. The method of claim 4 wherein said step of adhesively and removably securing is carried out by means of an adhesive tape.

6. The method of claim 5 wherein said step of adhesively and removably securing is carried out by means of polyethylene terephthalate tape.

7. A lead frame comprising:

first and second parallel and spaced-apart runners having a plurality of generally perpendicularly disposed tie bars therebetween, said tie bars being in a generally parallel and spaced apart relationship and said runners presenting parallel opposite upper and lower faces thereof;

a plurality of bonding pads detachably affixed to said runners and disposed interstitially between said tie bars, said bonding pads presenting opposite upper and lower surfaces thereof; and

a tape strip extending longitudinally between said runners and adhesively and removably secured to said runner lower faces and said bonding pad lower surfaces;

whereby said bonding pads may remain adhesively and removably secured to said tape strip after detachment from said runners.

8. The lead frame of claim 7 wherein said lead frame comprises a die bonded to said bonding pad.

9. The lead frame of claim 7 wherein said tape strip comprises an adhesive tape.

10. The lead frame of claim 9 wherein said adhesive tape comprises a polyethylene terephthalate tape.

11. A method for handling a plurality of components comprising the steps of:

providing a lead frame having first and second parallel and spaced-apart runners with a plurality of generally perpendicularly disposed tie bars therebetween in a generally parallel and spaced apart relationship, said lead frame presenting parallel opposite upper and lower faces thereof;

interstitially disposing bonding pads between said tie bars, said bonding pads being detachably affixed to said lead frame and presenting opposite upper and lower surfaces thereof; and

longitudinally extending a tape strip along said lead frame, said tape strip being adhesively and removably secured to said lead frame lower face and said bonding pad lower surface;

whereby said bonding pads may remain adhesively and removably secured to said tape strip after detachment from said lead frame.

12. The method of claim 11 wherein said step of longitudinally extending is carried out by means of an adhesive tape.

13. The method of claim 12 wherein said step of longitudinally extending is carried out by means of polyethylene terephthalate tape.