Abstract An improvement to a process for fabricating packages suitable for use in integrated circuits having a ceramic portion and an electrically conductive portion containing a high density of a plurality of individual component leads and at least one connecting lead wherein the connecting lead extends from a central pad portion through the ceramic portion to a frame portion. The component leads are spaced apart from the central pad portion by a predetermined pattern and extend through the ceramic portion to a frame portion. The ceramic portion, in addition to forming a base for the pad portion and a major segment of the leads, also forms a hermetic seal covering a sizeable segment of the leads. The pad portion, a minor segment of the leads and the frame portion are outside the seal to enable subsequent final assembly. The improvement comprises fabricating the electrically conductive portion having the component leads attached to the central pad forming the ceramic portion and thereafter removing a portion of the component leads to form the predetermined pattern. The improvement enables alignment of the leads to be maintained. A preferred method of removing the pattern is by positioning the package, after the ceramic portion is formed, under a properly shaped electrode and establishing a sufficient potential difference between the electrically conductive portion and the electrode to enable accurate removal of the pattern by electrical discharge machining.
A process for fabricating a package suitable for use in integrated circuits, said process comprising a. fabricating an electrically conductive metal member comprising a frame extending around the perimeter of said member, a central pad and a high density of a plurality of individual leads each being cOnnected to said pad and said frame, said leads comprising a plurality of component leads and at least one connecting lead; b. molding a ceramic portion that provides a support for said pad, covers and hermetic seals a large segment of each lead without covering and sealing the portions of each lead adjacent to the pad and the frame; and c. removing a predetermined segment of the component leads adjacent to said pad and external to said ceramic without the removal of said ceramic or any portion of said connecting lead adjacent to said pad to establish a predetermined pattern between said pad and one end of said component leads by positioning said predetermined segments under a properly designed electrode and establishing a suitable potential difference between the predetermined segments and said electrode to achieve an electrical discharge between said electrode and said predetermine segments to simultaneously remove said segments and thus produce said desired pattern.
Claim 2
Dependent Claim
203 words
A process for fabricating a package suitable for use in integrated circuits, said process comprising a. fabricating an electrically conductive metal member comprising a frame extending around the perimeter of said member, a central pad and a high density of a plurality of individual leads each being cOnnected to said pad and said frame, said leads comprising a plurality of component leads and at least one connecting lead; b. molding a ceramic portion that provides a support for said pad, covers and hermetic seals a large segment of each lead without covering and sealing the portions of each lead adjacent to the pad and the frame; and c. removing a predetermined segment of the component leads adjacent to said pad and external to said ceramic without the removal of said ceramic or any portion of said connecting lead adjacent to said pad to establish a predetermined pattern between said pad and one end of said component leads by positioning said predetermined segments under a properly designed electrode and establishing a suitable potential difference between the predetermined segments and said electrode to achieve an electrical discharge between said electrode and said predetermine segments to simultaneously remove said segments and thus produce said desired pattern.
Claim 3
Dependent Claim
16 words
An improvement according to claim 1 wherein the number of component leads are greater than 20.
Claim 4
Dependent Claim
21 words
An improvement according to claim 1 wherein the center-to-center lead spacing between each individual said component leads is about 50 mils.
Claim 5
Dependent Claim
21 words
An improvement according to claim 1 wherein the center-to-center lead spacing between each individual said component leads is about 100 mils.