FIB Deposited Molybdenum Micro Contact for VLSI Circuit Edit

Abstract

Platinum and tungsten have been widely used for making electrical contact using FIB for circuit edit. However they find limitation in small structure via filling. Molybdenum is becoming one of the promising materials to be used in FIB for electrical contact. Electrical characterization of FIB deposited molybdenum contact is described in this paper. Electrical resistivity, via filling capability, electro migration resistance and environmental resistance of FIB deposited molybdenum has been studied. FIB deposited molybdenum has shown better via filling capability and improved electro migration resistance. However molybdenum contacts are found to be susceptible to humidity induced degradation. Recapping the device after circuit edit with appropriate epoxy potting compound is found to provide excellent protection against humidity induced degradation.