Semiconductor assembly with beam lead construction and method

Claim 2

In a method for fabricating a semiconductor assembly having beam leads, providing a semiconductor body having a planar surface, forming a plurality of semiconductor devices in said body with each of the semiconductor devices having at least one junction extending to said surface and defining a region in said body and having a contact area generally on said surface, forming a layer of insulating material on said surface, forming openings in said layer of insulating material, forming contact pad means on said layer of insulating material extending through said openings for making contact with said contact areas, delineating a plurality of dice in said semiconductor body with each die having certain semiconductor devices therein, depositing a thick layer of photoresist in an initially solid form over said contact pads to a thickness in excess of approximately 1/2 mil, forming openings in said thick layer of photoresist in registration with said contact pad means, forming beam leads overlying said photoresist and extending through said openings to make electrical contact with said contact pad means and being physically secured thereto, said beam leads extending over the boundaries of said dice and overlying adjacent dice and with the beam leads of each die being insulated from the beam leads of adjacent dice, and removing the thick layer of photoresist so that the beam leads are cantilevered and have their lower surfaces spaced above the layer of insulating material a distance in excess of approximately 1/2 mil and separating the body to form separate and individual dice with the beam leads mounted thereon.

Claim 3

A method as in claim 1 wherein said delineation is carried out by forming scribe lines in the surface before the thick layer of photoresist is put in place.

Claim 4

A method as in claim 1 together with the step of forming indicia on the beam leads on the underside of the same.

Claim 5

A method as in claim 1 together with evaporating a thin layer of gold on said photoresist and thereafter electroforming the beam leads.

Claim 6

A method as in claim 1 together with the step of forming a first lead means carried by said body and interconnecting said devices and forming additional lead means interconnecting said devices at the same time that the beam leads are formed to provide at least one portion which spans and is spaced above a portion of said first lead means.

Claim 7

In a method for fabricating a semiconductor assembly having beam leads, providing a semiconductor body having a planar surface, forming a plurality of semiconductor devices in said body with each of the semiconductor devices having at least one junction extending to said surface and defining a region in said body and having a contact area generally on said surface, forming a layer of insulating material on said surface, forming openings in said layer of insulating material, forming contact pad means on said layer of insulating material extending through said openings for making contact with said contact areas, delineating a plurality of dice in said semiconductor body with each die having certain semiconductor devices therein, depositing a dry thick layer of photoresist over said contact pads, said photoresist having a photolithographic layer and a clear plastic layer, said clear plastic layer being removed prior to placement of the photoresist over said contact pads, baking the photoresist at an elevated temperature to reduce the stickiness of the photoresist, forming openings in said thick layer of photoresist in registration with said contact means, forming beam leads overlying said photoresist and extending through said openings to make electrical contact with said contact pad means and being physically secured thereto, said beam leads extending over the boundaries of said dice and overlying adjacent dice and with the beam leads of each die being insulated from the beam leads of adjacent dice, and removing the thick layer of photoresist so that the beam leads are cantilevered and have their lower surfaces spaced above the layer of insulating material a distance in excess of approximately 1/2 mil and separating the body to form separate and individual dice with the beam leads mounted thereon.

Claim 8

In a method for fabricating a semiconductor assembly having beam leads, providing a semiconductor body having a planar surface, forming a plurality of semiconductor devices in said body with each of the semiconductor devices having at least one junction extending to said surface and defining a region in said body and having a contact area generally on said surface, forming a layer of insulating material on said surface, forming openings in said layer of insulating material, forming contact pad means on said layer of insulating material extending through said openings for making contact with said contact areas, delineating a plurality of dice in said semiconductor body with each die having certain semiconductor devices therein, depositing a dry thick layer of photoresist over said contact pads, said photoresist having a photolithographic layer and a clear plastic layer, said clear plastic layer being removed prior to placement of the photoresist over said contact pads, baking the photoresist at an elevated temperature to reduce the stickiness of the photoresist, forming openings in said thick layer of photoresist in registration with said contact means, forming beam leads overlying said photoresist and extending through said openings to make electrical contact with said contact pad means and being physically secured thereto, said beam leads extending over the boundaries of said dice and overlying adjacent dice and with the beam leads of each die being insulated from the beam leads of adjacent dice, and removing the thick layer of photoresist so that the beam leads are cantilevered and have their lower surfaces spaced above the layer of insulating material a distance in excess of approximately 1/2 mil and separating the body to form separate and individual dice with the beam leads mounted thereon.

Claim 9

A method as in claim 6 wherein said photoresist is applied to the semiconductor body by drawing said photoresist down onto the semiconductor body by use of a vacuum.

Claim 10

In a method for fabricating a semiconductor assembly having beam leads, providing a semiconductor body having a planar surface, forming a plurality of semiconductor devices in said body with each of the semiconductor devices having at least one junction extending to said surface and defining a region in said body and having a contact area generally on said surface, forming a layer of insulating material on said surface, forming openings in said layer of insulating material, forming contact pad means on said layer of insulating material extending through said openings for making contact with said contact areas, delineating a plurality of dice in said semiconductor body with each die having certain semiconductor devices therein, placing a sheet of photoresist having a thickness in excess of approximately 0.5 mil over the contact pads, drawing the sheet of photoresist down onto the semiconductor body by use of a vacuum to form a thick layer of photoresist on said body, forming openings in said thick layer of photoresist in registration with said contact pad means, forming beam leads overlying said photoresist and extending through said openings to make electrical contact with said contact pad means and being physically secured thereto, said beam leads extending over the boundaries of said dice and overlying adjacent dice and with the beam leads of each die being insulated from the beam leads of adjacent dice, removing the thick layer of photoresist so that the beam leads are cantilevered and have their lower surfaces spaced above the layer of insulating material a distance in excess of approximately 1/2 mil, and separating the body to form separate and individual dice with the beam leads mounted thereon.

Claim 11

In a method for fabricating a semiconductor assembly having beam leads, providing a semiconductor body having a planar surface, forming a plurality of semiconductor devices in said body with each of the semiconductor devices having at least one junction extending to said surface and defining a region in said body and having a contact area generally on said surface, forming a layer of insulating material on said surface, forming openings in said layer of insulating material, forming contact pad means on said layer of insulating material extending through said openings for making contact with said contact areas, delineating a plurality of dice in said semiconductor body with each die having certain semiconductor devices therein, placing a sheet of photoresist having a thickness in excess of approximately 0.5 mil over the contact pads, drawing the sheet of photoresist down onto the semiconductor body by use of a vacuum to form a thick layer of photoresist on said body, forming openings in said thick layer of photoresist in registration with said contact pad means, forming beam leads overlying said photoresist and extending through said openings to make electrical contact with said contact pad means and being physically secured thereto, said beam leads extending over the boundaries of said dice and overlying adjacent dice and with the beam leads of each die being insulated from the beam leads of adjacent dice, removing the thick layer of photoresist so that the beam leads are cantilevered and have their lower surfaces spaced above the layer of insulating material a distance in excess of approximately 1/2 mil, and separating the body to form separate and individual dice with the beam leads mounted thereon.