Although not new, it might be timely considering the analysis underway related to Apple's A6 processor from the new iPhone 5.
Paul Boldt has begun to unravel more of the mystery of Apple's semiconductor program
with its latest foray into system-on-chip development. More is sure to come soon.
Until then, here is an educational video from Professor Chris Bishop entitled
How to Make a Microprocessor
that very nicely explains one key aspect of semiconductor manufacturing - lithography. This is the process of printing the physical designs onto chips so that various chemical processing techniques can create the nanoscale features that enable the incredible computing performance we all take for granted.