Actually, it's much worse than that -- when you talk about chips akin to
a Pentium 6, which gets (IIRC) 4 dies on a single wafer (and that needs
an "oversize" wafer puller; you'd get 1-2 dies on the "standard" wafer
of 3-4 years ago), price goes up in inverse proportion to the fallout
rate.  It's effectively impossible to fab a wafer without some defects
-- you get crystal imperfections in the wafer substrate, errors in
microlithography and epitaxy in creating the circuitry in/on the
silicon, contamination (even in vacuum fab conditions), and the end
result is that the best fabs on Earth can only produce about 1 wafer in
4 without defects, which means a minimum fallout of around 6% and likely
much higher; as recently as a couple years ago, fallout for Pentium 4
chips was 80% when they first hit the market (which went a long way to
explain their original pricing of close to $1000 each).  The bigger the
chip, the exponentially higher the fallout in a given fab environment,
and it's hideously expensive to reduce fallout by cleaning up a fab
(remember, you're "cleaning up" a place that's already so clean you need
an electron microscope to see the dirt, and might have to search for
hours to find a single speck).

The CCD sensor chips used in the Sloane Digital Sky Survey telescope
instrument cost over $1 million each, in a form factor similar to the
above 56x56 mm and with something like 20+ megapixels, without Bayer or
Foveon color capability.  Things have advanced considerably since those
chips were made (the Survey was completed in 2000, IIRC), but comparable
chips with color capability likely still wholesale for something like
$50,000 (if anyone makes one at all) -- which would translate to a
digital back incorporating such a chip selling for more than most of the
houses in the United States.  The price won't really start to come down
until they can start selling in quantity, which can't happen when you
can't get a second mortgage big enough to buy the end product -- it'll
be several years yet before there's a 56x56 color sensor that can
produce a camera or back under $20k.  There might *never* be one I can
afford, because the limits of silicon fab capability (limits set by the
laws of physics governing the operation of the circuits, not by fab
technology itself) are only about eight years out at Moore's Law growth
rates.

"Mxsmanic" posted:
"...
Well, they need to work on it.
..."

Actually ... they are ... to the tune of several BILLION dollars a year.

That technology is not cheap ... see Donald Qualls posting above for a very
good but very abbreviated look at the actual problem.

[I know ... I know ... you actually meant it as a facetious remark ...]