New Rumor: BSI APS-C sensor coming to the RF mount

In an interesting rumor CanonRumors indicates that according to one of their good sources, an APS-C RF mount camera is coming in the second half of next year featuring a BSI APS-C sensor.  BSI or backside illuminated sensor is something that Canon has never done before.

I'm a little intrigued by this rumor because it seems that Canon is confident in its fabrication of BSI substrates to support mass quantity fabrication by later next year.  A stacked sensor by nature features a BSI substrate for the photodiode layer so we know Canon can do it (sort of).  All we've heard to date is obviously the R3 and some cinema cameras featuring stacked sensors - neither of which are what I would consider significant quantity. However, creating a non-stacked BSI sensor is more of a technical challenge that Canon has never done before.

I suspect this sensor will push above 32MP since Canon already has a very good 32MP sensor.

What will BSI deliver?  A BSI sensor features no wiring around the photodiode, and the photodiode is closer to the top of the sensor. So this delivers slightly better performance in terms of dynamic range and ISO invariance.  The sensors also feature better performance in the corners because the light doesn't have to "bounce" down into the sensor as far to hit the photodiode and when the light angle is low as it is in the corners, the closer the photodiode is to the top the better.  Technically it also can be slightly faster since the wiring is underneath the photodiode and can be more optimized for heat and speed.

The rumors suggest that there will be multiple cameras featuring this sensor.  Could this also be the EOS-M M5? I know "EOS-M is dead, Jim' but until we hear about Canon creating a set of APS-C lenses for the RF mount, the EOS-M is the only APS-C mirrorless system that Canon has, even after they create this RF APS-C camera.

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