Canon Patent Application: Method of Manufacturing Back Side Illuminated Dual Pixel AF Sensor

This patent application indicates a method of manufacturing of what appears to be a stacked illuminated sensor that appears to be like a Back Side illuminated sensor - at least the resulting sensor is formed to be the same structure as a BSI sensor.

For instance, here's a front side illuminated sensor versus a backside illuminated sensor;

From this, you can see that it's very distinct where the wiring exists between the two sensors.  The BSI (backside illuminated sensor) has the wiring underneath the photodiodes.  While this above diagram is a little simplistic the basic principle is demonstrated.

If we look at this patent, we clearly see the sensor is described is similar to the (1) illustration, a back side illuminated sensor.

This would allow Canon to further increase the dynamic range and sensitivity of their sensors.

As Canon states;

 According to the present invention, the solid-state imaging device is provided having an advantageous structure for the production in accordance with an advantageous manufacturing method and the manufacturing method in the density of the charge accumulation region or pixel.
 

Japan Patent Application 2020-194965