US5440170A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Semiconductor device having a die pad with rounded edges and its manufacturing method
Assignee: Fujitsu Ltd
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Filing: 1991-09-09
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Granted: 1995-08-08
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Expires: 2011-09-09
Abstract
Abstract PCT No. PCT/JP91/01195 Sec. 371 Date Jun. 29, 1992 Sec. 102(e) Date Jun. 29, 1992 PCT Filed Sep. 9, 1991 PCT Pub. No. WO92/04730 PCT Pub. Date Mar. 19, 1992.A semiconductor device employs a lead frame including a die pad (24) and a plurality of leads (25) provided outside the die pad, and is manufactured by sealing the die pad and its periphery by a resin after the die pad is fitted with the semiconductor chip (11). The die pad (24) is formed separately from the main part of the lead frame provided with leads, and is rounded at an entire outermost edge thereof and includes a flat plate shape. This die pad can be either formed rounded with ceramic or resin, or formed in metal and given a rounded edge through honing.
Inventors
- 👤 Kazuto Tsuji
- 👤 Yoshiyuki Yoneda
- 👤 Junichi Kasai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 16:23
CPC Classifications
H; H10; H10W; H10W70/00; H10W70/40; H10W70/421; H10W70/424; H10W70/411; H10W70/427; H10W70/429; H10W70/435; H10W74/00; H10W90/00; H10W90/701; H10W90/751; H10W90/756
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
88 words
A semiconductor device manufactured employing a lead frame including a die pad and a plurality of leads provided outside said die pad, and manufactured by sealing of said die pad and its periphery by resin after said die pad is fitted with a semiconductor chip, said die pad being formed separately from a main part of the lead frame having leads and having a flat plate shape, wherein said die pad has a rounded outermost edge having a radius of curvature greater than or equal to 0.03 mm.
Claim 2
Dependent Claim
88 words
A semiconductor device manufactured employing a lead frame including a die pad and a plurality of leads provided outside said die pad, and manufactured by sealing of said die pad and its periphery by resin after said die pad is fitted with a semiconductor chip, said die pad being formed separately from a main part of the lead frame having leads and having a flat plate shape, wherein said die pad has a rounded outermost edge having a radius of curvature greater than or equal to 0.03 mm.
Claim 3
Dependent Claim
29 words
A semiconductor device as claimed in claim 1, wherein said die pad is made of a ceramic and said outermost edge is rounded during forming of said die pad.
Claim 4
Dependent Claim
29 words
A semiconductor device as claimed in claim 1, wherein said die pad is made of a resin and said outermost edge is rounded during forming of said die pad.
Claim 5
Dependent Claim
25 words
A semiconductor device as claimed in claim 1, wherein said die pad is made of a metal and said outermost edge is rounded by honing.
Claim 6
Independent Claim
99 words
A method of manufacturing a semiconductor comprising the steps of: forming a die pad with a rounded outermost edge having a radius of curvature greater than or equal to 0.03 mm, forming a main part of a lead frame including interconnected leads and a support bar for supporting said die pad, joining said support bar with said die pad, mounting a semiconductor chip on the die pad with which said support bar is joined, wire-bonding said semiconductor chip with the plurality of leads, and sealing, by resin, the semiconductor chip onto the said die pad and the wire-bonded leads.
Claim 7
Independent Claim
99 words
A method of manufacturing a semiconductor comprising the steps of: forming a die pad with a rounded outermost edge having a radius of curvature greater than or equal to 0.03 mm, forming a main part of a lead frame including interconnected leads and a support bar for supporting said die pad, joining said support bar with said die pad, mounting a semiconductor chip on the die pad with which said support bar is joined, wire-bonding said semiconductor chip with the plurality of leads, and sealing, by resin, the semiconductor chip onto the said die pad and the wire-bonded leads.
Claim 8
Dependent Claim
29 words
A semiconductor device as claimed in claim 2, wherein the area of said die pad is less than an area defined by tip ends of the plurality of leads.
References Cited (Backward Citations)
JPS5676542A
Cited
US4984059A
Cited
JPS5979536A
Cited
JPS5996757A
Cited
JPS59117141A
Cited
JPS59175753A
Cited
JPS6077432A
Cited
US4714952A
Cited
US4918511A
Cited
US4884124A
Cited
JPS6354759A
Cited
US4942452A
Cited
JPS63308359A
Cited
JPS6414942A
Cited
JPS6481257A
Cited
US5119171A
Cited
JPH01243531A
Cited
JPH01251747A
Cited
JPH022046A
Cited
JPH02138765A
Cited
JPH0290663A
Cited
JPH02129953A
Cited
JPH0383366A
Cited
US5083186A
Cited
US5196725A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-08-07 | 1999-02-06 | 1999-08-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-08-07 | 2003-02-06 | 2003-08-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-08-07 | 2007-02-06 | 2007-08-08 | $7700.00 | Window Closed / Lapsed |