Hitting the physical boundaries of affordable semiconductor
technology is not that scary since we have very satisfactory
computing and semiconductor parts at this point.
640k ought to be enough for everyone - Bill Gates
But seriously. Flash memory is experiencing some problem. The problem is that there were too many foundries built: investment overshoot.
Until some of these go bankrupt or the volume catches up with production volume there will be somewhat less money available for investment of new technology.
But that doesn´t mean that the technological progress is in real danger.
Lithography is still progressing in accordance to Moore's law. EUVL is set for the 22 node, while immersion (in combination with) double patterning are already available for the higher nodes.
Beyond theat it becomes difficult. Except for the challenges sketched above it is going to be extremely tough to find for instance the right resists (foto development layer), or to contain overlay problems (alignment of patterns).
And I don't think that quantum computing is ready to take over in 2013 or so (if ever).
But even for that there is also a solution. Go vertical. They are going to cheat their way out of Moores law. Stacking of structures still allows for an increase of the number of units per chip, while keeping the feature size similar.