Principle and application of a bifunctional laser linking and cutting structure for microelectronic circuits in standard CMOS-technology

Abstract The combination of a laser link and fuse in one device results in a new bifunctional laser linking and cutting structure. This new laser switch unites a vertical link structure and a fuse in a vertical arrangement to reduce the area requirements. The laser switch allows metal lines to be linked and disconnected simultaneously. Due to its excellent switch characteristics, it is well suited for configuration and repair purposes in microelectronic circuits. This new approach reduces the processing time per bus defect by 50%, in addition to lowering the area overhead by 20% for the laser structure. The structure has been designed and fabricated in a standard three-level metal CMOS process and has been successfully verified. The laser-links formed exhibit a very low resistance (Rmedian = 1.7 Ω). Both linking and cutting structures were processed with 100% yield.