Originally posted by Peter Zack more than $5,000 per finished chip.
Originally posted by rparmar The price of sensors goes up exponentially with the size
Old sources, exaggerated cost estimates...
From
IC Knowledge - 300mm Wafer Costs, a 300mm 0.13µm linewidth logic wafer was $3,400 in 2001. It surely is less than $2,000 today.
A 300mm wafer has the surface of thirty 56×41.5mm^2 chips(81 FF chips). Maybe twenty sensors due to waste (imperfect layout).
The yield goes down "exponentially" with size. But that's only a problem for very large sizes, not for normal sizes.
Let y1 be the yield rate (good/overall rate) for APS-C and y2 that for medium size.
Then: y2 = y1^6.3
With y1=90%, we get y2=51% (=twice the cost due to lower yield rate). I think a yield rate of 90% for APS-C is realistic because pixel defects can be tolerated.
Overall, this yields a cost estimate for a medium format sensor (2009) of
Cost (56mm×41.5mm CMOS sensor) = $200 ($2000 / 20 / 0.51)
jct us101 was rather correct in his comment even if by pure chance
--
Note:
If y1=80% only, y2 drops to 25% and the cost estimate increases to $400, and $1000 for y1=70%. But that's about it.
Note 2:
Add to the above cost for cutting, testing and packaging.
UPDATE:
I found this for the defect density:
http://www.icknowledge.com/trends/defects.pdf
With a defect density of 0.04/cm^2 (year 2000, 2009 projection is 0.01/cm^2 ...), we get 0.147 defects / APS-C-sized CMOS chip.
This translates with good accuracy to y1=85% or y2=35% => $290 per medium format sensor.
Add to this the cost for development depreciation, cutting, testing, packaging and we end up at about
$500.