TSMC's 12-inch wafer fab
Cowen & Co. analyst Timothy Arcuri cited Asian supply chain checks when making the prediction in a Monday morning note to investors. A copy of the report was provided to AppleInsider.
Arcuri's sources signaled that the 5.5-inch iPhone will feature a more powerful application processor than its smaller sibling, though no details were given as to the disparity. Apple has made similar moves in the past; the A7 processor in the iPad Air is clocked at 1.39 gigahertz, for instance, compared to 1.29 gigahertz for the otherwise-identical part in the iPad mini with Retina display.
There is some indication that the difference could be more than semantic, however. Arcuri also said that the processor in the 5.5-inch model could ship with a larger die, hinting at a more wide-ranging architectural split.
A larger die might be a sign that the 5.5-inch model will feature additional on-die silicon, such as a larger array of graphics processing cores. Alternatively, it might suggest that Apple will make the two chips -- believed to be the "A8" -- in different fabrication plants using different processes.
At least one rumor previously suggested that Apple would split A8 manufacturing between Taiwanese semiconductor giant TSMC and South Korea-based Samsung, though further reports indicated that TSMC had instead won the full order.
In addition the processor differences, Arcuri believes that both iPhone 6 models could sport different touch modules. Taipei-based TPK currently supplies touch modules for the iPhone, though a change could be in the works as the company is said to have been chosen as the manufacturer of silver nanowire-based parts for the so-called "iWatch."