An optimised process is presented to fabricate co-planar metal-insulator-me
tal nanojunctions down to an inter-electrode distance of 5 nm. Simulation o
f the e-beam insulation of the PMMA/SiO2/Si interface is used to optimise t
he PMMA resist thickness and the exposure strategy. The process was well st
abilised to provide a full statistical analysis of the number of nanojuncti
ons produced per wafer. A 10% throughput was reached for 5 nm giving a mass
production of about 100 nanojunctions per 2 inches wafer all equipped with
their interconnection pads.