Plastic molded package with heat sink for integrated circuit devices

Claim 2

Structure comprising: a semiconductor die having a first surface containing a plurality of die contact pads, and a second surface opposite the first surface; a heat sink having a planar first surface, and a planar second surface proximal to and opposite the first surface; a die attach adhesive attaching the second surface of the die to the first surface of the heat sink; a plurality of electrically conductive leads, each lead having an inner end and an outer end, an electrically insulative adhesive layer attaching a first portion of each of the inner ends to the first surface of the heat sink such that heat is conducted from said heat sink outwardly through said plurality of leads; a plurality of electrically conductive bond wires, each bond wire connecting one of the die contact pads to the inner end of one of the leads; an encapsulant encapsulating the heat sink, semiconductor die, die attach adhesive, bond wires, and an inner portion of the leads including said first portion of said lead inner ends, the second surface of the heat sink remaining exposed outside the encapsulant; and wherein the electrically insulative adhesive layer is an adhesive-coated tape.

Claim 3

Structure comprising: a semiconductor die having a first surface containing a plurality of die contact pads, and a second surface opposite the first surface; a heat sink having a planar first surface and a planar second surface proximal to and opposite the first surface; a die attach adhesive attaching the second surface of the die to the first surface of the heat sink; a plurality of electrically conductive leads, each lead having an inner end and an outer end; a plurality of electrically conductive bond wires, each bond wire connecting one of the die contact pads to the inner end of one of the leads; an encapsulant encapsulating the heat sink, semiconductor die, die attach adhesive, bond wires, and an inner portion of the leads; and wherein at least one lead is formed with at least two bends, wherein the at least two bends are located within the encapsulant between an outer edge of the heat sink and an outer edge of the encapsulant; and wherein each of the at least two bends in the at least one lead has an inner angle measuring less than 180° and an outer angle measuring greater than 180°, the vertex of at least one of the inner angles being rounded.

Claim 4

Structure comprising: a semiconductor die having a first surface containing a plurality of die contact pads, and a second surface opposite the first surface; a heat sink having a planar first surface and a planar second surface proximal to and opposite the first surface; a die attach adhesive attaching the second surface of the die to the first surface of the heat sink; a plurality of electrically conductive leads, each lead having an inner end and an outer end; a plurality of electrically conductive bond wires, each bond wire connecting one of the die contact pads to the inner end of one of the leads; an encapsulant encapsulating the heat sink, semiconductor die, die attach adhesive, bond wires, and an inner portion of the leads; and wherein at least one lead is formed with at least two bends, wherein the at least two bends are located within the encapsulant between an outer edge of the heat sink and an outer edge of the encapsulant; and wherein each of the at least two bends in the at least one lead has an inner angle measuring less than 180° and an outer angle measuring greater than 180°, the vertex of at least one of the inner angles being rounded.

Claim 5

Structure as in claim 2, wherein the vertex of at least one of the outer angles is rounded.

Claim 6

Structure as in claim 1, wherein a sealing ring is formed on the heat sink on at least one surface perpendicular to the first surface of the heat sink.

Claim 7

Structure as in claim 4, wherein: said sealing ring extends outwardly from said heat sink perpendicular surface in a direction perpendicular to the first and second surfaces of the heat sink; and the thickness of said sealing ring measured parallel to said perpendicular surface of the heat sink, at said perpendicular surface is less than the thickness of the sealing ring at a location displaced laterally and outwardly from said perpendicular surface.

Claim 8

Structure as in claim 4, wherein the sealing ring has a winged cross-sectional shape.

Claim 9

Structure as in claim 4, wherein the sealing ring has a T-shaped cross-section.

Claim 10

Structure as in claim 1, wherein at least one lead is formed with at least two bends, the bends being located within the encapsulant between an edge of the heat sink and an edge of the encapsulant.

Claim 11

Structure comprising: a semiconductor die having a first surface containing a plurality of die contact pads, and a second surface opposite the first surface; a heat sink having a planar first surface, and a planar second surface proximal to and opposite the first surface; a die attach adhesive attaching the second surface of the die to the first surface of the heat sink; a plurality of electrically conductive leads, each lead having an inner end and an outer end, an electrically insulative adhesive layer attaching a first portion of each of the inner ends to the first surface of the heat sink such that heat is conducted from said heat sink outwardly through said plurality of leads; a plurality of electrically conductive bond wires, each bond wire connecting one of the die contact pads to the inner end of one of the leads; an encapsulant encapsulating the heat sink, semiconductor die, die attach adhesive, bond wires, and an inner portion of the leads including said first portion of said lead inner ends, the second surface of the heat sink remaining exposed outside the encapsulant; wherein a sealing ring is formed on the heat sink on at least one surface perpendicular to the first surface of the heat sink; wherein at least one lead is formed with at least two bends, the bends being located within the encapsulant between an edge of the heat sink and an edge of the encapsulant; and wherein said bends in said leads each have an inner angle measuring less than 180° and an outer angle measuring greater than 180°, the vertex of at least one of the inner angles being rounded.

Claim 12

Structure comprising: a semiconductor die having a first surface containing a plurality of die contact pads, and a second surface opposite the first surface; a heat sink having a planar first surface, and a planar second surface proximal to and opposite the first surface; a die attach adhesive attaching the second surface of the die to the first surface of the heat sink; a plurality of electrically conductive leads, each lead having an inner end and an outer end, an electrically insulative adhesive layer attaching a first portion of each of the inner ends to the first surface of the heat sink such that heat is conducted from said heat sink outwardly through said plurality of leads; a plurality of electrically conductive bond wires, each bond wire connecting one of the die contact pads to the inner end of one of the leads; an encapsulant encapsulating the heat sink, semiconductor die, die attach adhesive, bond wires, and an inner portion of the leads including said first portion of said lead inner ends, the second surface of the heat sink remaining exposed outside the encapsulant; wherein a sealing ring is formed on the heat sink on at least one surface perpendicular to the first surface of the heat sink; wherein at least one lead is formed with at least two bends, the bends being located within the encapsulant between an edge of the heat sink and an edge of the encapsulant; and wherein said bends in said leads each have an inner angle measuring less than 180° and an outer angle measuring greater than 180°, the vertex of at least one of the inner angles being rounded.

Claim 13

A heat sink with first planar and second planar surfaces, the second surface being opposite and substantially parallel to the first surface, wherein: the heat sink is formed with a sealing ring on at least one surface that is substantially perpendicular to the first and second surfaces of the heat sink; the sealing ring extending outwardly perpendicular to said perpendicular surface of the heat sink; the thickness of the sealing ring in a direction parallel to said perpendicular surface of the heat sink, at the perpendicular surface is less than a thickness of the sealing ring at a location displaced laterally and outwardly from said perpendicular surface; and wherein the heat sink has at least one surface perpendicular to the first and second surfaces of the heat sink that is roughened such that the encapsulant grips the at least one perpendicular surface forming a bond therewith.

Claim 14

A heat sink with first planar and second planar surfaces, the second surface being opposite and substantially parallel to the first surface, wherein: the heat sink is formed with a sealing ring on at least one surface that is substantially perpendicular to the first and second surfaces of the heat sink; the sealing ring extending outwardly perpendicular to said perpendicular surface of the heat sink; the thickness of the sealing ring in a direction parallel to said perpendicular surface of the heat sink, at the perpendicular surface is less than a thickness of the sealing ring at a location displaced laterally and outwardly from said perpendicular surface; and wherein the heat sink has at least one surface perpendicular to the first and second surfaces of the heat sink that is roughened such that the encapsulant grips the at least one perpendicular surface forming a bond therewith.

Claim 15

Structure as in claim 1, wherein a shelf is formed at an outer edge of the second surface of the heat sink, the shelf beginning at a predetermined location from the outer edge of the second surface of the heat sink and extending to a depth sufficient to form a squared off corner at said outer edge.

Claim 16

Structure as in claim 1, wherein a portion of the electrically insulative adhesive layer extends beyond a periphery of the heat sink such that shorting of said leads to said heat sink is prevented and stresses in the leads are distributed about said periphery.

Claim 17

Structure as in claim 1, wherein the heat sink has at least one surface perpendicular to the first and second surfaces of the heat sink that is roughened such that the encapsulant grips the at least one perpendicular surface forming a bond therewith.

Claim 18

A heat sink as in claim 10, wherein a shelf is formed along an outer edge of the second surface of the heat sink adjacent to said perpendicular surface, the shelf beginning at a predetermined location from the outer edge of the second surface of the heat sink and extending to a depth sufficient to form a squared off corner along said outer edge of the second surface.

Claim 19

A heat sink as in claim 10, wherein the sealing ring has a winged cross-sectional shape.

Claim 20

A heat sink as in claim 10, wherein the sealing ring has a T-shaped cross-section.

Claim 21

Structure as in claim 1, wherein a portion of the electrically insulative adhesive extends beyond the inner ends of the leads.

Claim 22

Structure as in claim 1, wherein the heat sink has at least one surface perpendicular to the first and second surfaces of the heat sink that is an etched surface such that the encapsulant grips the at least one perpendicular surface forming a bond therewith.

Claim 23

Structure as in claim 1, wherein the heat sink has at least one surface perpendicular to the first and second surfaces of the heat sink that is a black oxide-containing surface such that the encapsulant grips the at least one perpendicular surface forming a bond therewith.

Claim 24

Structure as in claim 1, wherein the heat sink has at least one surface perpendicular to the first and second surfaces of the heat sink that is a sand-blasted surface such that the encapsulant grips the at least one perpendicular surface forming a bond therewith.

Claim 25

Structure as in claim 9, wherein the vertex of at least one of the outer angles is rounded.

Claim 26

Structure as in claim 1, wherein a portion of the electrically insulative adhesive layer extends beyond the inner ends of the leads.