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US5962918A Expired / Lapsed US ⏱️ 0.0 years remaining

Semiconductor device having simple protective structure and process of fabrication thereof

Assignee: NEC Electronics Corp
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Filing: 1998-10-13
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Granted: 1999-10-05
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Expires: 2018-10-13
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Abstract

Abstract A semiconductor integrated circuit device has a protective structure between a semiconductor chip and a ball grid array, and the protective structure has a thin polyimide film bonded to the surface of the semiconductor chip and a thick stress relaxation layer covering conductive strips connected between pads on the surface and the ball grid array; when thermal stress is exerted on the ball grid array, the thick stress relaxation layer allows said ball grid array to move so as to take up the thermal stress.

Inventors

  • 👤 Naoto Kimura

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 16:20
CPC Classifications
H; H10; H10W; H10W72/00; H10W72/90; H10W70/00; H10W70/01; H10W70/05; H10W70/60; H10W70/62; H10W70/65; H10W70/654; H10W70/656; H10W72/01; H10W72/019; H10W72/01921; H10W72/01925; H10W72/20; H10W72/251; H10W72/252; H10W72/701; H10W72/921; H10W72/923; H10W72/941; H10W72/944; H10W72/9445; H10W72/951; H10W72/952

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 160 words
A semiconductor device comprising: a semiconductor chip having electric elements connected to conductive pads formed on a major surface thereof, an insulating layer covering said major surface and having holes to which said conductive pads are exposed, conductive strips formed on said insulating layer and having first portions respectively connected to said conductive pads, a stress relaxation layer thicker than said insulating layer, covering said conductive strips and having holes to which second portions of said conductive strips are exposed, solder balls received in said holes in said stress relaxation layer and soldered to said second portions, respectively, and a lifter provided between said second portion of said conductive strips and one of said solder balls for increasing the thickness of said stress relaxation layer, wherein said lifter is formed by a conductive wire bonded at both ends thereof to said second portion at a spacing in such a manner as to project an intermediate portion over said second portion.
Claim 2
Dependent Claim 160 words
A semiconductor device comprising: a semiconductor chip having electric elements connected to conductive pads formed on a major surface thereof, an insulating layer covering said major surface and having holes to which said conductive pads are exposed, conductive strips formed on said insulating layer and having first portions respectively connected to said conductive pads, a stress relaxation layer thicker than said insulating layer, covering said conductive strips and having holes to which second portions of said conductive strips are exposed, solder balls received in said holes in said stress relaxation layer and soldered to said second portions, respectively, and a lifter provided between said second portion of said conductive strips and one of said solder balls for increasing the thickness of said stress relaxation layer, wherein said lifter is formed by a conductive wire bonded at both ends thereof to said second portion at a spacing in such a manner as to project an intermediate portion over said second portion.
Claim 3
Dependent Claim 59 words
The semiconductor device as set forth in claim 1, further comprising a noble metal layer covering an inner surface defining each recess formed in said stress relaxation layer and electrically connected to the second portion of one of said conductive strips, and a solder layer laminated on said noble metal layer and bonded to one of said solder balls.
Claim 4
Dependent Claim 31 words
The semiconductor device as set forth in claim 2, in which said protective insulating layer, said conductive strips and said noble metal layer are formed of polyimide, aluminum and palladium, respectively.
Claim 5
Dependent Claim 133 words
A semiconductor device comprising: a semiconductor chip having electric elements connected to conductive pads formed on a major surface thereof, an insulating layer covering said major surface and having holes to which said conductive pads are exposed, conductive strips formed on said insulating layer and having first portions respectively connected to said conductive pads, a stress relaxation layer thicker than said insulating layer, covering said conductive strips and having holes to which second portions of said conductive strips are exposed, solder balls received in said holes in said stress relaxation layer and soldered to said second portions, respectively, wherein said stress relaxation layer includes a covering layer formed so that said conductive strips are sandwiched between said insulating layer and said covering layer and a spacer layer is laminated on said covering layer.
Claim 6
Dependent Claim 133 words
A semiconductor device comprising: a semiconductor chip having electric elements connected to conductive pads formed on a major surface thereof, an insulating layer covering said major surface and having holes to which said conductive pads are exposed, conductive strips formed on said insulating layer and having first portions respectively connected to said conductive pads, a stress relaxation layer thicker than said insulating layer, covering said conductive strips and having holes to which second portions of said conductive strips are exposed, solder balls received in said holes in said stress relaxation layer and soldered to said second portions, respectively, wherein said stress relaxation layer includes a covering layer formed so that said conductive strips are sandwiched between said insulating layer and said covering layer and a spacer layer is laminated on said covering layer.
Claim 7
Dependent Claim 31 words
The semiconductor device as set forth in claim 4, in which said insulating layer and said covering layer are formed of polyimide, and said spacer layer is formed of epoxy resin.
Claim 8
Dependent Claim 35 words
The semiconductor device as set forth in claim 5, in which said covering layer and said spacer layer are of the order of 10 microns thick and of the order of 100 microns thick, respectively.

References Cited (Backward Citations)

US5376584A Cited
US5753973A Cited
US5726500A Cited
US5604379A Cited
US5844304A Cited
US5834844A Cited
US5793117A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2002-10-04 2003-04-05 2003-10-05 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2006-10-04 2007-04-05 2007-10-05 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2010-10-04 2011-04-05 2011-10-05 $7700.00 Window Closed / Lapsed

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