The present day implementation of complex integrated circuits covering >1000 mm2 on a single wafer requires redundancy techniques. In such wafer-scale systems, the operable circuit blocks (called cells) with >1000 transistors each are interconnected by on-wafer bus lines. This allows the avoidance of defective cells and system customization to create several different circuits from the same prefabricated wafer design. We have built wafer-scale circuits using focused laser spots to make connections, cut lines, and optically test the resultant paths.
© 1984 Optical Society of AmericaPDF Article