Very informative article looking at rising costs when going under 28nm........

http://www.fool.com/investing/general/2014/06/03/a-potential-problem-for-qualcomm-inc.aspx

"You might think that this cost increase isn't all that bad, but the mere fact that it increases at all is devastating. Take Qualcomm's 28-nanometer Snapdragon 800. According to Chipworks, the die-size comes in at about 118 square millimeters. Given that Apple's A7 -- built on a similar 28-nanometer process -- can pack about 1 billion transistors into about a 102 square millimeter area, we can conclude that the Snapdragon 800 has roughly 1 billion transistors.

Qualcomm says the Snapdragon 808 and 810 (next-generation parts built on TSMC's 20-nanometer process) will be "multi-billion transistor" designs. Let's assume, for the sake of discussion, that this means the Snapdragon 808 is a 2-billion transistor design and the 810 (with beefier graphics, more CPU cores) has 2.5 billion transistors. This would suggest the cost of building these chips will be twice or more that of the prior generation."