The main problem as I see it is that Canon don't really have any real development momentum (or budget!) on higher resolution processes. They outsource almost everything except for the larger format sensors.
The biggest difference between the others and Canon is that all the other manufacturers are all dominated by their small-sensor image sensors sales, that already now are manufactured at 90 and 110-130nm metal processes on 300mm wafers. Panasonic and TSMC will start volume shipping of sensors made on 65/45nm rules in Q1 2013. Lower mask resolutions than 130nm are not enough to land you any sales any more. Most cellphone and compact camera sensors are manufactured at those levels now, and have been for the last few years. Also consider the fact that some of the others have very large yearly revenues from logic CMOS processes at 45, 32 and even 22nm levels. All of those markets are areas where Canon totally lack any type of experience. Canon outsource all more advanced fabs on their camera bill-of-materials.
The Digic sensors are made by UMC http://www.umc.com/english/class_300/index.asp, and were designed by Texas Instruments http://www.ti.com/lsds/ti/apps/videovision/end_equipment.page
The memory is most often made by Samsung http://www.samsung.com/global/business/semiconductor/product/consumer-dram/overview
The memory/Digic package-on-package mount has to be outsourced, since Canon cannot do it themselves, and it is believed that UMC does the mounting too.
Other peripheral control and logic chips are TI, Mitsubishi, AD and Fairchild.
And is that different from Nikon how? Canon design their sensors and currently co-design the Digic 5, but to what extent they do it and what extent TI do it is not clear. What is clear is that TI don't sell that part or even mention it on their web site, so it is exclusive to Canon. Does not infer of course who own the most significant IP.
Going from a 500nm process to 180nm is like going from a 10MP FF camera to a 70MP camera in one generation. This means some really noticeable strains on the process, especially since the CMOS manufacturing process isn't as forgiving as just "taking pictures". You cant "scale to web size" and sharpen in post when you're making CIS wafers.
What you're basically asking from your equipment is to all of a sudden provide compact camera type linear resolution in a FF lens projection coverage - something almost unthinkable in the normal photographic world. The process has to be precise, to a degree where every single contrast and item on the new 70MP image is equal to or better than the 10MP camera - per pixel. In normal photographic resolution usage, we just want the final output to be good enough, which means that we downsample most images - we seldom deliver full-res images to the customers, and we seldom use full-res images in our own output.
Going from a 350nm mask to 250 and then 180nm and 12" wafers was a BIG step for most CMOS manufacturers, and most other manufacturers are a LOT bigger than Canon in this area.
So it's not that Canon COULDN'T do it. Even really small (in the imaging field) firms like STMicro can do it by stitching, and thereby tripling the unit prices. For Leica this isn't really a problem since the total BoM on a M series camera is most certainly lower than 2k USD. This gives a healthy margin up to the projected 7k USD end price point.
This isn't what Canon does. They live on volume, not on extreme margins.
Hold on, your making multiple assumptions here
1) Canon needs to make the leap, in volume, on FF at once otherwise they'll what exactly... go bankrupt?
2) Canon needs to sink billions (immediately) in order to compete with Sony's sensor manufacturing capability or indeed other (sensor) manufacturers to stay competitive on their own products
3) A 180nm sensor is the only way Canon can provide competitive products to Nikon / Sony
4) Canon cannot survive if it manufacturers its' own sensors
oh and presumably, Canon has been ignoring all this, has changed culture and wants to do it all together?
They presumably know what investment is possible, and what is required for their
next iteration of sensors. I'm also assuming that this information is not something recent, and that they have been developing capability. Not to the level to suddenly compete with Sony, but to a level that would be sufficient to remain profitable. Whether the next FF or APS-C will be 180um and whether they will design or design / manufacturer frankly is high conjecture. Anyone who wants to make a decision on their future camera purchases based on this conjecture is someone with more disposable income than I!
In another thread, it was mentioned that the latest Sxx sensor was 180um. And clearly that's an ocean away from FF manufacturing @ 180um, but maybe that is the first "volume" process for Canon and that elsewhere they are refining a low-yield FF capability. I'm happy to be wrong, but Sony & Nikon have not been manufacturing FF sensor for more than 5 years (less?), and that's not exactly a high volume capability either. Agreed it is more than Canon have been doing, and that may explain why Canon has taken so long to switch (problems) or just the bean counters (sweat assets / more risk adversed in a shrinking market)
But Sony doesn't have too many other lines of business making money for them. Finding their position in sensor manufacturing has been a great success. Canon is not looking to manufacturer sensor for smartphones and other areas, either because they don't have the capability or don't want to be there.
And presumably, that investment Sony has made is based on the diversity of sensors they produce and indeed the volume. Again, Canon is not in that market, and surely that means the investment - should they decide it will be viable over the next 10 years, is considerably less than Sony needs to.
Finally, are we sure a 320um or 250um with the other sensor tech that has been outlined would not provide a significant step-change for Canon sensors, and since it's been done to death that a photographer / photography is more than his sensor, then if Canon's next APS-C or FF sensor is not 180um does that definitively mean it won't be much different from the current sensors???
Think I'll go back to err, taking pictures on my dinosauric kit