Chipworks image sensor analyst Ray Fontaine publishes his thoughts on IISW 2015 and related topics, and also covering some parts of Ray's paper at the Workshop. Few quotes:
"As we head into the 3D integration era, I predict packaging inventions will rise as a percentage of the whole. It’s also natural that as the imaging community gains access to lower power and higher density processing all the dreams of years past will come to fruition in the form of innovation at the systems and software level."
"For the time being pixel scaling has essentially plateaued at the 1 µm generation so all the mobile small-pixel leaders have been looking for other knobs to turn. A lot of development has been done to embed color filters into the tungsten aperture grid metal. Sony and ON Semiconductor (Aptina) currently hold the world record (based on Chipworks’ analysis) for getting down to a 1.5 µm thick optical stack, as measured from the back-illuminated (BSI) silicon (Si) surface to the surface of the microlens. There doesn’t seem to be much more to do here, but time will tell."
"Sony has about a two year lead in the domain of stacking image sensor chips... Depending on which flavor of Sony stacked chip system used, the image signal processor (ISP) can be either a homegrown (Sony) 65 nm chip or a TSMC fab’d 40 nm chip... My summary presentation slide and message was: if you aren’t excited about chip stacking, you should become excited about chip stacking!"
Ray's IISW paper can be freely downloaded from Chipworks site.