Canon Patent Application: Stacked sensor global shutter

In this patent, Canon describes a method of having the storage cell on the secondary substrate, allowing for high-speed data transfer but this would also have the benefit of reducing the dynamic range loss of what would be the normal configuration of a global shutter based sensor.  From Canon's description, this is "near global shutter" having a storage unit (and a bump to transfer information to the secondary substrate for every 4 pixels)

In patent-speak;

On the other hand, the CMOS sensor provided with the simultaneous imaging function (global shutter functions) operates an electronic shutter as all the pixel coincidence, and it made it coincide exposure time is known. In this CMOS sensor, it has the accumulating part for usually storing the signal charge which the optoelectric transducer generated until reading is performed. And after exposing all the pixels simultaneously, by all the pixels, the signal charge which each optoelectric transducer generated is simultaneously transmitted to each accumulating part, and is held. Next, the signal charge currently held to each accumulating part is sequentially scanned for every line, and it outputs as a pixel signal. At this time, one of the methods of transmitting to an accumulating part simultaneously by all the pixels has the following. 

First, grouping of the pixel provided by the picture element region of the image sensor chip is carried out every 4 pixels, and the output common to each is provided. And the micro pad to which it corresponded to each community output is formed in the wiring layer side of an image sensor chip. Next, in the signal processing chip which faces, grouping of the sample hold circuit (SH circuit) where it corresponded to each pixel is carried out every four pieces, and the input common to each is provided. And the micro pad to which it corresponded to each community input is formed in the wiring layer side of a signal processing chip. It becomes possible to transmit to four SH circuits where it corresponds every 4 pixels to all the pixels by connecting between the micro pads of an image sensor chip and a signal processing chip to which it corresponds by micro bumps (for example, see Patent Document 1). These false global shutter functions enable it to transmit the pixel signal of all the pixels of an image sensor chip to the SH circuit of a signal processing chip substantially simultaneous.

Japan Patent Application 2018-152650