US3902148A — Semiconductor lead structure and assembly and met…

Claim 1

Independent Claim 236 words

A lead structure for use with a semiconductor device formed in a semiconductor body having at least portions of an electrical circuit formed therein and with contact pads in a predetermined pattern carried by the body and lying in a common plane and for use with a lead frame having a plurality of leads with the inner extremities arranged in a predetermined pattern, comprising a sheet of electrically conducting material, having a plurality of spaced lead arrays formed therein, each of said lead arrays comprising a plurality of leads formed from the sheet material and in one region thereof and being integral therewith, each of said leads being cantilevered and extending inwardly with its inner end being free, the free inner ends of the said leads having positions which conform to a pattern of the contact pads on the semiconductor body, portions of said leads remote from the free ends being positioned in a pattern which conforms to the predetermined pattern of the lead frame, each of said lead arrays including at least one support tab formed from said sheet and being integral with said sheet, said support tab being cantilevered so that said support tab has a free end, said free end of the support tab being positioned in the vicinity of the free ends of said leads, but being spaced outwardly from the innermost extremities of the leads and being spaced from the leads.

Claim 2

Dependent Claim 236 words

A lead structure for use with a semiconductor device formed in a semiconductor body having at least portions of an electrical circuit formed therein and with contact pads in a predetermined pattern carried by the body and lying in a common plane and for use with a lead frame having a plurality of leads with the inner extremities arranged in a predetermined pattern, comprising a sheet of electrically conducting material, having a plurality of spaced lead arrays formed therein, each of said lead arrays comprising a plurality of leads formed from the sheet material and in one region thereof and being integral therewith, each of said leads being cantilevered and extending inwardly with its inner end being free, the free inner ends of the said leads having positions which conform to a pattern of the contact pads on the semiconductor body, portions of said leads remote from the free ends being positioned in a pattern which conforms to the predetermined pattern of the lead frame, each of said lead arrays including at least one support tab formed from said sheet and being integral with said sheet, said support tab being cantilevered so that said support tab has a free end, said free end of the support tab being positioned in the vicinity of the free ends of said leads, but being spaced outwardly from the innermost extremities of the leads and being spaced from the leads.

Claim 3

Dependent Claim 18 words

A lead structure as in claim 1 wherein portions of said leads adjacent the free ends are convoluted.

Claim 4

Dependent Claim 28 words

A lead structure as in claim 1 wherein at least two of said support tabs are provided and wherein said support tabs are in alignment with each other.

Claim 5

Dependent Claim 29 words

A lead structure as in claim 1 wherein said sheet is in the form of an elongated strip having a plurality of said lead arrays arranged in a row.

Claim 6

Dependent Claim 24 words

A lead structure as in claim 4 wherein said lead arrays are arranged in pluralities of rows extending at right angles to each other.

Claim 7

Dependent Claim 19 words

A lead structure as in claim 1 wherein said sheet has a thickness of approximately 0.002 of an inch.

Claim 8

Dependent Claim 208 words

In a semiconductor assembly for use with a lead frame having a plurality of leads having free inner extremities arranged in a predetermined pattern, a semiconductor body having at least a portion of an electrical circuit formed therein and with contact pads in a predetermined pattern carried by the body and lying in a common plane and a sheet of electrically conducting material having a plurality of lead arrays formed therein, each of said lead arrays comprising a plurality of spaced leads formed from the sheet material in one region thereof and being formed integral therewith, each of said leads being cantilevered and extending inwardly, the inner ends of said leads conforming to the pattern of the pads, and means forming a bond between the inner ends of each lead array and the contact pads of a semiconductor body, portions of said leads remote from the inner ends of the leads being arranged in a pattern which corresponds to the predetermined pattern of the lead frame, each of said lead arrays including a support tab formed from the sheet material and being integral with the sheet material, said support tab being cantilevered and extending inwardly into a region which is spaced from the inner ends of the leads.

Claim 9

Dependent Claim 208 words

In a semiconductor assembly for use with a lead frame having a plurality of leads having free inner extremities arranged in a predetermined pattern, a semiconductor body having at least a portion of an electrical circuit formed therein and with contact pads in a predetermined pattern carried by the body and lying in a common plane and a sheet of electrically conducting material having a plurality of lead arrays formed therein, each of said lead arrays comprising a plurality of spaced leads formed from the sheet material in one region thereof and being formed integral therewith, each of said leads being cantilevered and extending inwardly, the inner ends of said leads conforming to the pattern of the pads, and means forming a bond between the inner ends of each lead array and the contact pads of a semiconductor body, portions of said leads remote from the inner ends of the leads being arranged in a pattern which corresponds to the predetermined pattern of the lead frame, each of said lead arrays including a support tab formed from the sheet material and being integral with the sheet material, said support tab being cantilevered and extending inwardly into a region which is spaced from the inner ends of the leads.

Claim 10

Dependent Claim 40 words

A semiconductor assembly as in claim 7 together with the means for encapsulating said semiconductor body and the inner extremities of the leads while leaving the portions of the leads remote from the inner ends free of the encapsulating material.

Claim 11

Dependent Claim 21 words

A semiconductor assembly as in claim 7 wherein the inner end of the support tab is engaged by the encapsulatiNg means.

Claim 12

Dependent Claim 33 words

A semiconductor assembly as in claim 8 wherein portions of the leads adjacent the innermost ends of the leads of each lead array have convoluted portions which are covered by the encapsulating means.

Claim 13

Dependent Claim 254 words

In a semiconductor assembly for use with a lead frame having a plurality of spaced leads having free inner extremities arranged in a predetermined pattern, a semiconductor body having at least a portion of an electrical circuit formed therein with contact pads in a predetermined pattern carried by the semiconductor body and lying in a common plane, a sheet of electrically conducting material having a plurality of lead arrays formed therein, said lead arrays comprising a plurality of spaced leads formed from the sheet material in one region thereof, each of said leads extending inwardly and having inner ends, the inner ends of the leads conforming to the pattern of the contact pads of a semiconductor body, means forming a bond between the contact pads of the semiconductor body and the inner ends of the leads of a lead array, each of said lead arrays including at least one support tab formed from the sheet and being cantilevered inwardly between the leads into a region in the vicinity of the semiconductor body, means encapsulating the semiconductor body, the inner extremities of the leads and the inner extremity of the said support tab while leaving the outer ends of the leads free of the encapsulating means, the outer extremities of the leads being separated from the sheet material so that the leads, the semiconductor body and the encapsulating means are supported solely by the support tab whereby the electrical circuit in said semiconductor body can be electrically tested while still being retained in said sheet.

Claim 14

Dependent Claim 254 words

In a semiconductor assembly for use with a lead frame having a plurality of spaced leads having free inner extremities arranged in a predetermined pattern, a semiconductor body having at least a portion of an electrical circuit formed therein with contact pads in a predetermined pattern carried by the semiconductor body and lying in a common plane, a sheet of electrically conducting material having a plurality of lead arrays formed therein, said lead arrays comprising a plurality of spaced leads formed from the sheet material in one region thereof, each of said leads extending inwardly and having inner ends, the inner ends of the leads conforming to the pattern of the contact pads of a semiconductor body, means forming a bond between the contact pads of the semiconductor body and the inner ends of the leads of a lead array, each of said lead arrays including at least one support tab formed from the sheet and being cantilevered inwardly between the leads into a region in the vicinity of the semiconductor body, means encapsulating the semiconductor body, the inner extremities of the leads and the inner extremity of the said support tab while leaving the outer ends of the leads free of the encapsulating means, the outer extremities of the leads being separated from the sheet material so that the leads, the semiconductor body and the encapsulating means are supported solely by the support tab whereby the electrical circuit in said semiconductor body can be electrically tested while still being retained in said sheet.

Claim 15

Dependent Claim 22 words

A lead structure as in claim 11 wherein portions of the lead adjacent the inner ends of the leads have convoluted portions.

Claim 16

Dependent Claim 35 words

A semiconductor asembly as in claim 11 wherein the outer extremities of the leads of each array are positioned in a pattern which corresponds to the predetermined pattern of the leads of the lead frame.

Claim 17

Dependent Claim 215 words

In a semiconductor assembly, a semiconductor body having at least a portion of an electrical circuit formed therein and with contact pads in a predetermined pattern carried by the body and lying in a common plane, a plurality of first leads bonded to said contact pads, said first leads extending outwardly from the semiconductor body and having outer extremities which lie in a predetermined pattern, at least one support tab disposed between the leads and being electrically isolated from the leads, first encapsulating means encapsulating said semiconductor body and the portions of said first leads in engagement with said contact pads and encapsulating at least a portion of the support tab, portions of said first leads adjacent the inner extremities of the leads having convolutions therein, said portions having convolutions therein being encapsulated by said first encapsulating means, a plurality of spaced second leads having inner extremities arranged in a predetermined pattern corresponding to the pattern of the outer extremities of said first leads, means forming a bond between said spaced lleads and the outer extremities of said first named leads and second encapsulating means encapsulating said first encapsulating means and the inner extremities of said second leads and the remaining portions of said first leads which are not encapsulated by said first encapsulating means.

Claim 18

Dependent Claim 215 words

In a semiconductor assembly, a semiconductor body having at least a portion of an electrical circuit formed therein and with contact pads in a predetermined pattern carried by the body and lying in a common plane, a plurality of first leads bonded to said contact pads, said first leads extending outwardly from the semiconductor body and having outer extremities which lie in a predetermined pattern, at least one support tab disposed between the leads and being electrically isolated from the leads, first encapsulating means encapsulating said semiconductor body and the portions of said first leads in engagement with said contact pads and encapsulating at least a portion of the support tab, portions of said first leads adjacent the inner extremities of the leads having convolutions therein, said portions having convolutions therein being encapsulated by said first encapsulating means, a plurality of spaced second leads having inner extremities arranged in a predetermined pattern corresponding to the pattern of the outer extremities of said first leads, means forming a bond between said spaced lleads and the outer extremities of said first named leads and second encapsulating means encapsulating said first encapsulating means and the inner extremities of said second leads and the remaining portions of said first leads which are not encapsulated by said first encapsulating means.

Claim 19

Dependent Claim 52 words

A semiconductor assembly as in claim 14 wherein said spaced second leads extend from the second encapsulating means in two opposing directions and wherein portions of said second leads are formed to extend in a direction generally at right angles to the direction in which they extend from the second encapsulating means.

Claim 20

Dependent Claim 165 words

In a semiconductor assembly, a semiconductor body having at least a portion of an electrical circuit formed therein and with contact pads in a predetermined pattern carried by the body and lying in a common plane, a plurality of first spaced leads having inner extremities in contact with the contact pads carried by the semiconductor body and having the remaining portions thereof extending outwardly from the semiconductor body, first encapsulating means encapsulating said semiconductor body and the inner extremities of said first leads, a plurality of spaced second leads, means bonding the inner extremities of the second leads to the outer extremities of the first leads, said inner extremities of said second leads being provided with raised wedge-like portions which engage the outer extremities of said first leads, second encapsulating means encapsulating said first encapsulating means, the remaining portions of said first leads and the inner extremities of said second leads so that portions of said second leads extend free of said second encapsulating means.

Claim 21

Dependent Claim 165 words

In a semiconductor assembly, a semiconductor body having at least a portion of an electrical circuit formed therein and with contact pads in a predetermined pattern carried by the body and lying in a common plane, a plurality of first spaced leads having inner extremities in contact with the contact pads carried by the semiconductor body and having the remaining portions thereof extending outwardly from the semiconductor body, first encapsulating means encapsulating said semiconductor body and the inner extremities of said first leads, a plurality of spaced second leads, means bonding the inner extremities of the second leads to the outer extremities of the first leads, said inner extremities of said second leads being provided with raised wedge-like portions which engage the outer extremities of said first leads, second encapsulating means encapsulating said first encapsulating means, the remaining portions of said first leads and the inner extremities of said second leads so that portions of said second leads extend free of said second encapsulating means.

Claim 22

Dependent Claim 33 words

A semiconductor assembly as in claim 16 wherein portions of said first leads adjacent inner extremities of the same are convoluted and wherein said convoluted portions are disposed within said first encapsulating means.

Claim 23

Dependent Claim 24 words

A semiconductor assembly as in claim 16 together with heat sink means secured to said semiconductor body and having contact with said encapsulating means.

Claim 24

Dependent Claim 32 words

An assembly as in claim 18 wherein said encapsulating means is in the form of a hermetically sealed ceramic package and wherein said heat sink means is secured to the ceramic package.

Claim 25

Dependent Claim 18 words

An assembly as in claim 19 together with additional external heat sink means secured to said ceramic package.

Claim 26

Dependent Claim 19 words

An assembly as in claim 19 wherein said heat sink means extends out of and beyond said encapsulating means.

Claim 27

Dependent Claim 44 words

An assembly as in claim 18 wherein said heat sink means and said encapsulating means are formed with mating surfaces to retain said heat sink means within said encapsulating means and to thereby prevent said heat sink means from separating from said semiconductor body.

Claim 28

Dependent Claim 25 words

A semiconductor assembly as in claim 16 together with heat sink means secured to said semiconductor body and making contact with said first encapsulating means.

Claim 29

Dependent Claim 34 words

A semiconductor assembly as in claim 23 wherein said heat sink means and said first encapsulating means are provided with mating surfaces to prevent said heat sink means from separating from the semiconductor body.

Claim 30

Dependent Claim 20 words

A semiconductor assembly as in claim 23 wherein said heat sink means is in contact with said second encapsulating means.

Claim 31

Dependent Claim 19 words

A semiconductor assembly as in claim 25 wherein said heat sink means extends out of the second encapsulating means.

Claim 32

Dependent Claim 117 words

In a semiconductor assembly, a semiconductor body having at least a portion of an electrical circuit formed therein and with contact pads in a predetermined pattern carried by the body and lying in a common plane, a plurality of first spaced leads having inner extremities in contact with the contact pads carried by the semiconductor body and having remaining portions thereof extending outwardly from the semiconductor body, heat sink means independent of the leads secured to the semiconductor body, first encapsulating means encapsulating said semiconductor body, the inner extremities of said first leads and at least a portion of the heat sink means, said first encapsulating means and said heat sink means being formed of different materials.

Claim 33

Dependent Claim 117 words

In a semiconductor assembly, a semiconductor body having at least a portion of an electrical circuit formed therein and with contact pads in a predetermined pattern carried by the body and lying in a common plane, a plurality of first spaced leads having inner extremities in contact with the contact pads carried by the semiconductor body and having remaining portions thereof extending outwardly from the semiconductor body, heat sink means independent of the leads secured to the semiconductor body, first encapsulating means encapsulating said semiconductor body, the inner extremities of said first leads and at least a portion of the heat sink means, said first encapsulating means and said heat sink means being formed of different materials.

Claim 34

Dependent Claim 31 words

An assembly as in claim 27 wherein said heat sink means and said first encapsulating means are formed so that the heat sink means extends out of the first encapsulating means.

Claim 35

Dependent Claim 31 words

An assembly as in claim 27 wherein said first encapsulating means is in the form of a ceramic package and wherein said heat sink means is secured to the ceramic package.

Claim 36

Dependent Claim 30 words

A semiconductor assembly as in claim 27 wherein said first encapsulating means is formed of a plastic and wherein said heat sink means extends out of the first encapsulating means.

Claim 37

Dependent Claim 79 words

An assembly as in claim 27 together with a plurality of spaced second leads, means bonding the inner extremiTies of the second leads to the outer extremities of the first leads, second encapsulating means encapsulating said first encapsulating means, the remaining portions of said first leads and the inner extremities of said second leads so that portions of said second leads extend free of said second encapsulating means, said heat sink means making contact with said second encapsulating means.

Claim 38

Dependent Claim 18 words

An assembly as in claim 31 wherein said heat sink means extends out of said second encapsulating means.

Claim 39

Dependent Claim 175 words

In a semiconductor assembly a semiconductor body having at least a portion of an electrical circuit formed therein and with contact pads in a predetermined pattern carried by the body and lying in a common plane, a plurality of first spaced leads formed of Kovar and having inner extremities in contact with the contact pads carried by the semiconductor body and having the remaining portions thereof extending outwardly from the semiconductor body, first encapsulating means encapsulating said semiconductor body and the inner extremities of said first leads, a plurality of spaced second leads formed of tin plated steel, means bonding the inner extremities of the second leads to the outer extremities of the first leads, said inner extremities of the second leads being provided with raised wedge-like portions which engage the outer extremities of the first leads and second encapsulating means encapsulating said first encapsulating means, the remaining portions of said first leads and the inner extremities of said second leads so that portions of said second leads extend free of said second encapsulating means.

Claim 40

Dependent Claim 175 words

In a semiconductor assembly a semiconductor body having at least a portion of an electrical circuit formed therein and with contact pads in a predetermined pattern carried by the body and lying in a common plane, a plurality of first spaced leads formed of Kovar and having inner extremities in contact with the contact pads carried by the semiconductor body and having the remaining portions thereof extending outwardly from the semiconductor body, first encapsulating means encapsulating said semiconductor body and the inner extremities of said first leads, a plurality of spaced second leads formed of tin plated steel, means bonding the inner extremities of the second leads to the outer extremities of the first leads, said inner extremities of the second leads being provided with raised wedge-like portions which engage the outer extremities of the first leads and second encapsulating means encapsulating said first encapsulating means, the remaining portions of said first leads and the inner extremities of said second leads so that portions of said second leads extend free of said second encapsulating means.

Claim 41

Dependent Claim 33 words

A semiconductor assembly as in claim 33 wherein the upper portions of said wedge-like portions are substantially free of tin so that a good weld is formed between the steel and the Kovar.

Claim 42

Dependent Claim 150 words

A lead frame for use with a lead structure having a plurality of leads with inner extremities arranged in a predetermined pattern adapted to be connected to contact pads carried by a semiconductor body having at least portions of an electrical circuit formed therein and having outer extremities arranged in a pattern comprising a sheet of electrically conducting material, a plurality of sets of leads formed therein with each of the sets of leads comprising a plurality of leads formed from the sheet material in one region thereof and being integral therewith, each lead being cantilevered and extending inwardly with its inner end being free, the free inner ends of the leads having portions which conform to the pattern of the outer extremities of the lead structure, the inner extremities of said leads being provided with raised wedge-like portions which are adapted to engage the leads of the lead structure.

Claim 43

Dependent Claim 150 words

A lead frame for use with a lead structure having a plurality of leads with inner extremities arranged in a predetermined pattern adapted to be connected to contact pads carried by a semiconductor body having at least portions of an electrical circuit formed therein and having outer extremities arranged in a pattern comprising a sheet of electrically conducting material, a plurality of sets of leads formed therein with each of the sets of leads comprising a plurality of leads formed from the sheet material in one region thereof and being integral therewith, each lead being cantilevered and extending inwardly with its inner end being free, the free inner ends of the leads having portions which conform to the pattern of the outer extremities of the lead structure, the inner extremities of said leads being provided with raised wedge-like portions which are adapted to engage the leads of the lead structure.

Claim 44

Dependent Claim 24 words

A lead frame as in claim 35 wherein the sheet is formed of tin-plated steel and wherein the lead structure is formed of Kovar.

Claim 45

Dependent Claim 42 words

A lead frame as in claim 36 wherein the upper portions of said wedge-like portions are substantially free of tin so that a good weld can be formed between the steel of the lead frame and the Kovar of the lead structure.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1978-08-25	1979-02-24	1979-08-26	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1982-08-25	1983-02-24	1983-08-26	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1986-08-25	1987-02-24	1987-08-26	$7700.00	Window Closed / Lapsed

Semiconductor lead structure and assembly and method for fabricating same

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