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CA1145860A Expired / Lapsed CA ⏱️ 0.0 years remaining

Leadframe for leaded semiconductor chip carriers

Assignee: Nortel Networks Corp
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Filing: 1981-01-29
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Granted: 1983-05-03
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Expires: 2001-01-29
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Abstract

Abstract A LEADFRAME FOR LEADED SEMICONDUCTOR CHIP CARRIERS Abstract of the Disclosure A leadframe with parallel side members and parallel transverse members defining chip receiving areas along the frame, has a chip pad at each area. A support lead extends from each corner of the chip pad to corresponding conjunctions of side and transverse members. A U-shaped support bar extends between each adjacent pair of support leads, each support bar including spaced parallel leg portions connected at inner ends to the support leads and at the outer ends by a lead support portion. Leads extend from each lead support portion towards the chip pad. By this means the chip can be assembled to the pad and wire bonding between chip and leads carried out and the leads can be preformed or not, as desired, prior to encapsulation. After encapsulation, the lead support portions can be trimmed off but the encapsulated device is still held in the lead frame but the leads are electrically isolated from each other. Testing can be carried out while devices are still in the leadframe.

Inventors

  • 👤 John C. Walker
  • 👤 Manfred Thumm

Bibliographic Details

Application Number —
Jurisdiction CA
Data Source google_patents
Last Synchronized 2026-11-09 18:31
CPC Classifications
H; H10; H10W; H10W70/00; H10W70/40; H10W70/421; H10W70/438; H10W72/00; H10W72/50; H10W72/541; H10W72/5449; H10W72/851; H10W72/874; H10W72/884; H10W90/00; H10W90/701; H10W90/751; H10W90/756

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 161 words
A leadframe for leaded semiconductor chip carriers, said lead frame comprising, two parallel, spaced apart side members, a plurality of parallel transverse members extending between the side members and connected thereto to define a plurality of areas spaced along the frame; a rectangular chip pad positioned centrally in each area, the sides of the pad parallel to the side and transverse members; a support lead extending from each corner of the chip pad to a corresponding conjunction of a side and a transverse member; a U-shaped support bar extending between each adjacent pair of support leads, the support bar including spaced parallel leg portions connected at inner ends to the support leads and at outer ends by a lead support portion, the lead support portions parallel to related side and transverse members; and a plurality of leads extending from each lead support portion inwards towards the chip pad, the leads having inner ends adjacent to but spaced from the chip pad.
Claim 2
Dependent Claim 161 words
A leadframe for leaded semiconductor chip carriers, said lead frame comprising, two parallel, spaced apart side members, a plurality of parallel transverse members extending between the side members and connected thereto to define a plurality of areas spaced along the frame; a rectangular chip pad positioned centrally in each area, the sides of the pad parallel to the side and transverse members; a support lead extending from each corner of the chip pad to a corresponding conjunction of a side and a transverse member; a U-shaped support bar extending between each adjacent pair of support leads, the support bar including spaced parallel leg portions connected at inner ends to the support leads and at outer ends by a lead support portion, the lead support portions parallel to related side and transverse members; and a plurality of leads extending from each lead support portion inwards towards the chip pad, the leads having inner ends adjacent to but spaced from the chip pad.
Claim 3
Dependent Claim 20 words
A leadframe as claimed in claim 1, including perforations along each side, for positioning of said areas at predetermined positions.
Claim 4
Dependent Claim 32 words
A leadframe as claimed in claim 1, including guide edges on said support bar, said guide edges engaging with guide members on a bending apparatus, to ensure correct bending of said leads.
Claim 5
Dependent Claim 16 words
A leadframe as claimed in claim 1, including a semiconductor chip mounted on said chip pad.
Claim 6
Dependent Claim 34 words
A leadframe as claimed in claim 4, said chip including a plurality of contact areas on an upper surface, and wire bonds extending from the inner ends of the leads to the contact areas.
Claim 7
Dependent Claim 18 words
A leadframe as claimed in claim 5, said chip, chip pad and inner ends of said leads encapsulated.
Claim 8
Dependent Claim 24 words
A leadframe as claimed in claim 6, said chip, chip pad and inner ends of said leads sealed between a base and a cap.
Claim 9
Dependent Claim 33 words
A leadframe as claimed in claim 4, said leads and said support bar, preformed, whereby said leads extend downward normal to the plane of the leadframe, in a direction away from said chip.
Claim 10
Dependent Claim 29 words
A leadframe as claimed in claim 1, said leg portions of said support bars connected to said support leads at a position intermediate the ends of the support leads.
Claim 11
Dependent Claim 21 words
A leadframe as claimed in claim 1, including lateral projections on said leads, spaced from the inner ends of the leads.

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