Leadframe designs for plastic overmold packages

a technology of plastic overmolding and leadframes, applied in the direction of semiconductor devices, semiconductor/solid-state device details, electrical devices, etc., can solve problems such as the mechanical integrity of the package becoming an issu

Inactive Publication Date: 2006-10-26
BOULIN DAVID M +1
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  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

The retention slots enhance the mechanical integrity of the package by increasing retention forces, reducing the likelihood of lead separation and electrical failure, while maintaining the compact lead configuration.

Problems solved by technology

Thus as the number of leads are reduced, the mechanical integrity of the package may become an issue.

Method used

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  • Leadframe designs for plastic overmold packages
  • Leadframe designs for plastic overmold packages
  • Leadframe designs for plastic overmold packages

Examples

Experimental program
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Embodiment Construction

[0019]FIG. 1 shows a conventional twenty lead plastic overmolded package. This figure is nearly a scale representation of the MO-166 standard format approved by JEDEC. It should be understood at the outset that the MO-166 packaging format is represented here by way of example only. A wide variety of plastic overmolded package designs are available in the packaging industry. Many will share the properties described below. All plastic overmolded package products that have the features to be described are intended to be included in the scope of the invention. Referring again to FIG. 1, the plastic overmolded package body is shown at 11 and the twenty leads, ten to a side, are indicated at 12. In the embodiment shown, the leads are bent downward in a so-called gull-wing shape to allow for convenient surface mounting. This is the most familiar JEDEC MO-166 plastic overmolded package profile. For a better understanding, the plastic overmolded package of FIG. 1 is shown in FIG. 2 in plan v...

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Abstract

The specification describes a plastic overmolded package for high power devices that has a very low lead count, typically fewer than eight, and in a preferred embodiment, only two. The leads occupy essentially the same linear space as the multiple leads in a conventional package and thus have a wide-blade configuration. To improve mechanical integrity, the leads in the package are provided with retention slots to add back the equivalent of the plastic joints in the spaces that were eliminated due to the wide-blade design. The retention slots extend in the width dimension of the leads.

Description

RELATED APPLICATIONS [0001] This application is a continuation of application Ser. No. 10 / 939,763, filed Sep. 13, 2004.FIELD OF THE INVENTION [0002] This invention relates to leadframe designs used in plastic overmolded packages for integrated circuit (IC) and related devices. BACKGROUND OF THE INVENTION [0003] The most common form of packaging for electronic devices such as IC devices is a plastic housing. Typically, the electronic components are assembled on a metal leadframe and a polymer is molded over the assembly to encapsulate the device. The leadframe serves not only to support the electronic components, but has metal tabs that extend from the overmolded plastic and provide a means to electrically connect to the encapsulated electronic components. [0004] The leadframe, prior to assembly and encapsulation, typically is square or rectangular and has a center paddle to which a semiconductor chip is die bonded. The leads that provide electrical interconnection extend from the si...

Claims

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Application Information

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Patent Type & AuthorityApplications(United States)
IPC IPC(8): H01L23/495
CPCH01L23/3107H01L23/49562H01L2924/0002H01L2924/00H01L23/495
InventorBOULIN, DAVID M.SAFAR, HUGO F.
OwnerBOULIN DAVID M