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US5164815A Expired / Lapsed US ⏱️ 0.0 years remaining

Integrated circuit device and method to prevent cracking during surface mount

Assignee: Texas Instruments Inc
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Filing: 1991-07-15
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Granted: 1992-11-17
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Expires: 2011-07-15
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Abstract

Abstract A semiconductor package device is disclosed. In one embodiment, attached by its active face to a lead-on-chip leadframe having leadfingers is an integrated circuit. The integrated circuit has a roughened backside. An encapsulating material surrounds the integrated circuit and the lead-on-chip leadframe so that the leadfingers are exposed. The roughened backside surface helps to reduce package cracking arising from mounting the device to a printed circuit board by reflow solder.

Inventors

  • 👤 Thiam B. Lim

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 16:00
CPC Classifications
H; H10; H10W; H10W70/00; H10W70/40; H10W70/421; H10W70/435; H10D; H10D62/00; H10D62/10; H10D62/117; H10W70/411; H10W70/415; H10W70/424; H10W70/427; H10W70/429; H10W72/00; H10W72/071; H10W72/073; H10W72/851; H10W72/853; H10W72/865; H10W72/874; H10W72/884; H10W74/00; H10W74/10; H10W90/00; H10W90/701; H10W90/731; H10W90/736; H10W90/751; H10W90/756

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 67 words
A semiconductor device, comprising: an integrated circuit having an active face and an inactive backside; a leadframe connected to the active face of the integrated circuit by wirebonds, the integrated circuit and the leadframe forming a self supporting structure; an encapsulant to encapsulate the integrated circuit and the leadframe; and wherein the backside of the integrated circuit has a roughened surface to promote adhesion to the encapsulant.
Claim 2
Dependent Claim 67 words
A semiconductor device, comprising: an integrated circuit having an active face and an inactive backside; a leadframe connected to the active face of the integrated circuit by wirebonds, the integrated circuit and the leadframe forming a self supporting structure; an encapsulant to encapsulate the integrated circuit and the leadframe; and wherein the backside of the integrated circuit has a roughened surface to promote adhesion to the encapsulant.
Claim 3
Dependent Claim 15 words
The semiconductor device of claim 1 wherein the lead frame is a lead-on-chip lead frame.
Claim 4
Dependent Claim 14 words
The semiconductor device of claim 1 wherein the lead frame is a chip-on-lead leadframe.
Claim 5
Dependent Claim 15 words
The semiconductor device of claim 1 wherein the lead frame is a flip-chip lead frame.
Claim 6
Dependent Claim 82 words
A semiconductor packaged device having no chip support pad, comprising: a leadframe and a semiconductor die connected together to form a self supporting structure having no chip support pad and having wire bonds connecting leadfingers of the leadframe to terminals on the semiconductor die; a plastic mold compound to encapsulate the leadframe and the semiconductor die, thereby forming a packaged device; and wherein the semiconductor die has a roughened surface to promote adhesion between the semiconductor die and the plastic mold compound.
Claim 7
Dependent Claim 82 words
A semiconductor packaged device having no chip support pad, comprising: a leadframe and a semiconductor die connected together to form a self supporting structure having no chip support pad and having wire bonds connecting leadfingers of the leadframe to terminals on the semiconductor die; a plastic mold compound to encapsulate the leadframe and the semiconductor die, thereby forming a packaged device; and wherein the semiconductor die has a roughened surface to promote adhesion between the semiconductor die and the plastic mold compound.
Claim 8
Dependent Claim 56 words
The semiconductor packaged device of claim 5 wherein the semiconductor die has two major faces, one active face in contact with the leadframe by virtue of the wire bonds and one inactive face in contact with the plastic mold compound; and wherein the inactive face in contact with the plastic mold compound has the roughened surface.
Claim 9
Dependent Claim 19 words
The semiconductor packaged device of claim 6 wherein the roughened surface ranges from about 8 to 14 microinch Ra.

References Cited (Backward Citations)

US4003073A Cited
US4916519A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1995-11-17 1996-05-18 1996-11-17 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1999-11-17 2000-05-18 2000-11-17 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2003-11-17 2004-05-18 2004-11-17 $7700.00 Window Closed / Lapsed

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