"Our lab staff have removed the imaging chip from the 12 MP camera module and have found a Sony back-illuminated (Exmor R) CMOS image sensor. We were expecting to find TSV arrays around the periphery of the active pixel array, corresponding to Sony’s stacked chip (Exmor RS) technology platform. Sony hasn’t publicly announced the IMX260, but based on what we’ve been reading, we assume that is the part number. It’s a bit of a surprise that the IMX260 isn’t an Exmor RS sensor, as we’ve been documenting a lot of Sony design wins based on its 1st and 2nd generation Exmor RS technology. It seems the full chip PDAF functionality, which requires dual readout from each pixel, was implemented with a multi-chip solution rather than a stacked (CIS + ISP) solution.
The Sony IMX260 die size, as measured from the die seals, is 6.69 mm x 5.55 mm (37.1 mm2). There are no conventional die identification markings in use on the die, consistent with back-illuminated (stacked/non-stacked) Sony CIS chips. We confirmed a pixel pitch of 1.4 µm and a Bayer-patterned color filter array."
The 5MP front camera is based on 1.34um BSI pixel Samsung S5K4E6XP sensor:
Cnet's Youtube video shows Samsung Galaxy S7 camera presentation at MWC 2016: