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US 7,029,256 B2Granted
Leadframe and method for removing cleaning compound flash from mold vents
AssigneeMicron Technology, Inc.
InventorsVernon M. Williams, Michael D. Gifford
Life of this patent
Estimating the term…
Abstract
An integrated circuit leadframe is specially adapted to adhere to injection mold cleaning compounds in the area of vents for an injection mold. An area of a leadframe rail that is normally positioned adjacent a mold vent is provided with apertures, surface roughness or a surface coating to cause the cleaning compound to more tightly adhere to the leadframe rail. As a result, cleaning compound flash is removed from the vents when the leadframe is removed from the mold.
Claims16
A leadframe adapted for removing flash from mold vents, comprising:
- a pair of leadframe rails extending along opposite sides of the leadframe;
- and
- an attachment area formed on at least one of the leadframe rails, the attachment area having properties that cause the attachment area to adhere relatively well to a material forming the flash, the attachment area comprising a panel of material that is different from a material used to form the leadframe rail, the panel of material extending through the leadframe rail from one side of the leadframe rail to the other.
An injection mold for molding a package for an integrated circuit, the injection mold comprising:
- a first mold section including a plurality of mold cavities, a respective injection inlet adjacent each of the mold cavities, and a respective mold vent adjacent each of the mold cavities on adjacent an edge of the mold cavity opposite the injection inlet for the mold cavity;
- a second mold section including a plurality of mold cavities corresponding in number to the number of cavities included in the first mold section and having a size and a shape corresponding to the size and shape of the mold cavities in the first mold section;
- and
- a leadframe positioned between the first and second mold sections, the leadframe having a pair of leadframe rails extending along opposite sides of the leadframe, the leadframe further including a plurality of attachment areas formed on the leadframe rail adjacent each of the mold vents, each of the attachment areas having properties that cause the attachment area to adhere relatively well to a compound injected into the mold cavities and forming a flash in the mold vents, each of the attachment areas comprising a panel of material that is different from a material used to form the leadframe rail, the panel of material extending through the leadframe rail from one side of the leadframe rail to the other.
1 more element
An injection molding machine for molding integrated circuit packages, comprising:
- a first mold section including a plurality of mold cavities, a respective injection inlet adjacent each of the mold cavities, and a respective mold vent adjacent each of the mold cavities on adjacent an edge of the mold cavity opposite the injection inlet for the mold cavity;
- a second mold section including a plurality of mold cavities corresponding in number to the number of cavities included in the first mold section and having a size and a shape corresponding to the size and shape of the mold cavities in the first mold section;
- and
- a material reservoir containing a supply of a material that is to be injected into the mold cavities;
- an injection mechanism in fluid communication with the material reservoir and the injection vents, the injection mechanism forcibly injecting the material from the material reservoir into the mold cavities;
- a heating mechanism for heating the mold sections;
- and
- a leadframe positioned between the first and second mold sections, the leadframe having a pair of leadframe rails extending along opposite sides of the leadframe, the leadframe further including a plurality of attachment areas formed on the leadframe rail adjacent each of the mold vents, each of the attachment areas having properties that cause the attachment area to adhere relatively well to the material injected into the mold cavities and forming a flash in the mold vents, each of the attachment areas comprising a panel of material that is different from a material used to form the leadframe rail, the panel of material extending through the leadframe rail from one side of the leadframe rail to the other.
5 more elements
Dependencies are inferred from the claim text.