Any idea?
mainly improvement in equipment (lithography) plus solving some technical issues like doping concentration , gate leakage and substrate leakage and MOSfet engineering and tons of other stuff
y not 75nm well y not 74nm , if they have said any number , it would be questionable , but mainly i THINK this depends on the effectiveness of the reduction like from 90nm to 89nm it is not worth it as u will to do tons of R&D work plus pay tons of dollars on new equipment to get a nearly not that much performance difference so u have to do a market survey and see what will make u gain money , like some Fabs are still not going for lower nodes (AMS for instance) because they are satisfied with their own technology and have their paying custmers for this technology and of course their market study is not advising to go any lower (NOW), but someone like intel if they don't enhance their technology then they are done and to keep their performance slope they have to push their technology to the limit