From a blogger :
In less than three years, the estimated NRE cost has jumped from $85 M for a 45 nm design to over $170 M for 28 nm. Included in these NRE estimates are the cost of the design work, masks, embedded software (IP licenses), and yield ramp-up cost. The data presented shows an exponential growth for NRE for each new process node. Rough extrapolation would place 14 nm at $340 M and 7 nm at $680 M respectively.
http://hightechbizdev.com/2014/02/04/ira-feldman-high-technology-business-development-semi-iss-2014-scaling-innovation
Are these figures reasonable?