Patent US5336639A successfully refreshed from Google Patents.
US5336639A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for securing a semiconductor chip to a leadframe
Assignee: Motorola Solutions Inc
•
Filing: 1993-06-28
•
Granted: 1994-08-09
•
Expires: 2013-06-28
Abstract
Abstract A semiconductor chip (26) is attached to a leadframe (20, 30, 40). The leadframe (20, 30, 40) has an opening (24) or a cavity (34, 44) for receiving the semiconductor chip (26). The opening (24) or the cavity (34, 44) and the semiconductor chip (26) have corresponding shapes. The opening (24) or the cavity (34, 44) is made such that they are smaller than the size of the semiconductor chip (26) at room temperature. The opening (24) or the cavity (34, 44) is expanded and the semiconductor chip (26) is placed in the opening (24) or the cavity (34, 44). Subsequent to placing the semiconductor chip (26) in the opening (24) or the cavity (34, 44), the leadframe (20, 30, 40) is cooled so that an edge (25) of the leadframe grips a corresponding edge (29) of the semiconductor chip (26).
Inventors
- 👤 Benamanahalli K. Nagaraj
- 👤 Vern Hause
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 19:57
CPC Classifications
H; H10; H10W; H10W70/00; H10W70/40; H10W70/411; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49117; Y10T29/49121
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
130 words
A method for nonadhesively securing a semiconductor chip to a leadframe, comprising the steps of: providing the leadframe, wherein the leadframe has a semiconductor chip receiving region; forming a semiconductor chip receiving cavity in the semiconductor chip receiving region, the semiconductor chip receiving cavity having a first shape and a first area; providing the semiconductor chip, wherein the semiconductor chip has a second shape and a second area, the second shape corresponding to the first shape and the second area being larger than the first area; expanding the semiconductor chip receiving cavity such that the semiconductor chip receiving cavity has a third area, wherein the third area is larger than the second area; placing the semiconductor chip in the semiconductor chip receiving cavity; and shrinking the semiconductor chip receiving cavity.
Claim 2
Independent Claim
130 words
A method for nonadhesively securing a semiconductor chip to a leadframe, comprising the steps of: providing the leadframe, wherein the leadframe has a semiconductor chip receiving region; forming a semiconductor chip receiving cavity in the semiconductor chip receiving region, the semiconductor chip receiving cavity having a first shape and a first area; providing the semiconductor chip, wherein the semiconductor chip has a second shape and a second area, the second shape corresponding to the first shape and the second area being larger than the first area; expanding the semiconductor chip receiving cavity such that the semiconductor chip receiving cavity has a third area, wherein the third area is larger than the second area; placing the semiconductor chip in the semiconductor chip receiving cavity; and shrinking the semiconductor chip receiving cavity.
Claim 3
Dependent Claim
30 words
A method for nonadhesively securing a semiconductor chip to a leadframe as claimed in claim 1, wherein the step of expanding the semiconductor chip receiving cavity includes heating the leadframe.
Claim 4
Dependent Claim
31 words
A method for nonadhesively securing a semiconductor chip to a leadframe as claimed in claim 1, wherein the step of expanding the semiconductor chip receiving cavity includes uniformly expanding the leadframe.
Claim 5
Dependent Claim
30 words
A method for nonadhesively securing a semiconductor chip to a leadframe as claimed in claim 1, wherein the step of shrinking the semiconductor chip receiving cavity includes cooling the leadframe.
Claim 6
Dependent Claim
38 words
A method for nonadhesively securing a semiconductor chip to a leadframe as claimed in claim 1, wherein the step of providing the leadframe includes providing the leadframe with a flag, the flag having the semiconductor chip receiving cavity.
Claim 7
Dependent Claim
35 words
A method for nonadhesively securing a semiconductor chip to a leadframe as claimed in claim 1, wherein the step of providing the leadframe includes providing a heatsink, the heatsink having the semiconductor chip receiving cavity.
Claim 8
Independent Claim
103 words
A method for gripping a semiconductor substrate, comprising the steps of: providing the semiconductor substrate, wherein the semiconductor substrate has a major surface and is bounded along a periphery by an edge; providing a support, wherein the support has a major surface and a receptacle having an edge for gripping the edge of the semiconductor substrate, the edge of the receptacle substantially parallel to the edge of the semiconductor substrate; and gripping the edge of the semiconductor substrate with the edge of the receptacle, wherein the compressire stress on the semiconductor substrate is between approximately 100 and approximately 200 MegaPascals at room temperature.
Claim 9
Independent Claim
103 words
A method for gripping a semiconductor substrate, comprising the steps of: providing the semiconductor substrate, wherein the semiconductor substrate has a major surface and is bounded along a periphery by an edge; providing a support, wherein the support has a major surface and a receptacle having an edge for gripping the edge of the semiconductor substrate, the edge of the receptacle substantially parallel to the edge of the semiconductor substrate; and gripping the edge of the semiconductor substrate with the edge of the receptacle, wherein the compressire stress on the semiconductor substrate is between approximately 100 and approximately 200 MegaPascals at room temperature.
Claim 10
Dependent Claim
62 words
A method for gripping a semiconductor substrate as claimed in claim 7, wherein the step of gripping the edge of the semiconductor substrate comprises: expanding the support such that the receptacle is larger than the semiconductor substrate; inserting the semiconductor substrate in the receptacle; and shrinking the support such that the edge of the receptacle grips the edge of the semiconductor substrate.
Claim 11
Dependent Claim
26 words
A method for gripping a semiconductor substrate as claimed in claim 7, further including providing the receptacle as an opening, the opening extending through the support.
Claim 12
Dependent Claim
64 words
A method for gripping a semiconductor substrate as claimed in claim 7, further including providing the receptacle as a recess having a floor and walls, and the step of gripping the edge of the semiconductor substrate includes placing the semiconductor substrate in the recess such that the semiconductor substrate rests on the floor, and compressing the walls against the edge of the semiconductor substrate.
Claim 13
Dependent Claim
26 words
A method for gripping a semiconductor substrate as claimed in claim 10, further including providing an aperture in the floor, the aperture extending through the floor.
Claim 14
Dependent Claim
31 words
A method for gripping a semiconductor substrate as claimed in claim 8, wherein expanding the support includes heating the support, and the step of shrinking the support includes cooling the support.
Claim 15
Dependent Claim
39 words
A method for gripping a semiconductor substrate as claimed in claim 7, further including gripping the edge of the semiconductor substrate such that the major surface of the semiconductor substrate is co-planar with the major surface of the support.
Claim 16
Dependent Claim
70 words
A method for gripping a semiconductor substrate as claimed in claim 7, wherein the step of gripping the edge of the semiconductor substrate comprises: shrinking the semiconductor substrate, expanding the support such that the receptacle is larger than the semiconductor substrate; inserting the semiconductor substrate in the receptacle; expanding the semiconductor substrate; and shrinking the support such that the edge of the receptacle grips the edge of the semiconductor substrate.
Claim 17
Dependent Claim
78 words
A method for gripping a semiconductor substrate as claimed in claim 7, further including providing the semiconductor substrate such that the semiconductor substrate has a rectangular shape and two opposing edges, providing the receptacle such that the receptacle has a corresponding rectangular shape and two opposing edges, and gripping each of the two opposing edges of the semiconductor substrate with the two opposing edges of the support that correspond with the two opposing edges of the semiconductor substrate.
Claim 18
Independent Claim
61 words
A method for nonadhesively attaching a semiconductor substrate to a leadframe, comprising the steps of: providing the leadframe, wherein the leadframe has an opening, the opening being smaller than the semiconductor substrate; temporarily enlarging the opening; placing the semiconductor substrate in the opening; and shrinking the opening, wherein the step of shrinking the opening compresses the leadframe against the semiconductor substrate.
Claim 19
Independent Claim
61 words
A method for nonadhesively attaching a semiconductor substrate to a leadframe, comprising the steps of: providing the leadframe, wherein the leadframe has an opening, the opening being smaller than the semiconductor substrate; temporarily enlarging the opening; placing the semiconductor substrate in the opening; and shrinking the opening, wherein the step of shrinking the opening compresses the leadframe against the semiconductor substrate.
Claim 20
Dependent Claim
33 words
A method for nonadhesively attaching a semiconductor substrate to a leadframe as claimed in claim 16, further including expanding the opening by heating the leadframe and shrinking the opening by cooling the leadframe.
References Cited (Backward Citations)
US3766977A
Cited
US4816427A
Cited
US4893172A
Cited
US4979289A
Cited
US5081067A
Cited
US5202288A
Cited
US5166774A
Cited
US5198391A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-08-08 | 1998-02-07 | 1998-08-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-08-08 | 2002-02-07 | 2002-08-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-08-08 | 2006-02-07 | 2006-08-09 | $7700.00 | Window Closed / Lapsed |