Dielectric fracture leading to metallic connections by laser heating

Laser programmed connections between adjacent lines on the same level of metallization have been developed as a means to achieve high density linking for customization in programmable gate arrays and for additive redundancy in restructurable integrated circuits. The resistances of the connections were approximately 1Ω and the overlaying passivation remained in tact. Links were formed by focusing a pulsed laser between two adjacent lines of metal, one of which was connected to a lower level of metal through a contact via. The mechanism of link formation appears to be a fissure contained within planarized passivation due to the stress of thermal expansion of the metallization with molten aluminum filling the crack.