US 4,908,938 A · Method for repairing interconnect interruptions by bridging with congruent preforms

Abstract

A method for repairing interconnect interruptions. Faults at the interconnects occurring in manufacturing processes of printed circuit boards were previously repaired with suitable methods. The fashioning of the interconnects in a meander form and their miniaturization requires a completely new procedure. The dimensions of current interconnects amount, for example, to: width.times.height=70 .mu.m.times.20 .mu.m. For repairing such interconnects that are usually arranged in extremely tight proximity on an interconnect carrier, it is necessary to position preforms utilized for repair absolutely congruently on the interconnect interruption and to hold them until the joining zones are completely formed between the preform and the interconnect. This is achieved by use of an insulating foil having work windows and by use of a preform panel that contains a plurality of preforms. The preform is joined to the interconnect by resistance heating with a first electrode system and is separated from the preform panel with a second electrode system.

Claims20

Dependent claims

A method for repairing interconnect interruptions by bridging with congruent preforms and mutual joining by resistance heating, comprising the steps of:

placing an insulating foil having a work window on the interconnect interruption such that the interconnect interruption appears at least approximately centrally in the work window;
lowering a preform that is congruent with the interconnect interruption, the preform being held in a preform panel, onto the insulating foil and onto the interconnect by lowering the preform panel;
pressing the preform within the work window onto the interconnect with a first electrode system;
mechanically and electrically joining the preform to the interconnect at both sides of the interconnect interruption;
and
cutting off those parts of the preform projecting beyond the work window of the insulating foil at the edge of the work window by resistance heating with a second electrode system.

3 more elements

A method for repairing interconnect interruptions by bridging with congruent preforms and mutual joining by resistance heating, comprising the steps of:

selecting a preform from various preform panels, the selected preform being congruent with a predetermined interrupt having the interconnect interruption, the preform panels containing a plurality of different preforms corresponding to interconnect configurations that occur on a printed circuit board;
placing an insulating foil having a work window on the interconnect interruption such that the interconnect interruption appears at least approximately centrally in the work window;
lowering the selected preform that is congruent with the interconnect interruption, the selected preform being held in the preform panel, onto the insulating foil and onto the interconnect by lowering the preform panel;
pressing the selected preform within the work window onto the interconnect with a first electrode system;
mechanically and electrically joining the selected preform to the interconnect at both sides of the interconnect interruption;
and cutting off those parts of the selected preform projecting beyond the work window of the insulating foil at the edge of the work window by resistance heating with a second electrode system.

3 more elements

Dependencies are inferred from the claim text.

Method for repairing interconnect interruptions by bridging with congruent preforms

Life of this patent

Method for repairing interconnect interruptions by bridging with congruent preforms

Life of this patent

Abstract

Claims20