Simple lithographic technique for chip repairing using a light microscope

We have developed a simple lithographic technique for repairing damaged chi ps, even after the end of the whole fabrication process, by using simply a light microscope for lithographic definition. In the usual laboratory; prac tice, it can happen that the fabricated chips present defects which make th em useless, such as: broken metallic lines, or unwanted contacts between cl ose elements on the same layer. Repairing these defects requires that the d amaged area is lithographically defined in the photoresist,;so that a subse quent step of film deposition (for broken lines) or etching (for unwanted c ontacts) can be performed. The white illumination of a usual light microsco pe with a reduced field (by means of a diaphragm already present in the mic roscope optical path) can provide the necessary light source to expose-the resist. Both spots and narrow lines (several microns wide)can be defined in the resist; we give the details of operation and show some examples from o ur devices. (C) 1999 American Vacuum Society. [S0734-211X(99) 10702-9].