RE: [Leica] Chips

["Austin Franklin" <darkroom@ix.netcom.com>]

> I've spoken to a friend in the industry and he has
> confirmed that CCDs are now made the same way as other
> chips, in predetermined die sizes on wafers that are
> then cut up and wire-bonded, etc.

Now?  They've always been made that way.  The only other way is discrete
components!

I've been doing ASIC (Application Specific Integrated Circuit) design for 25
years, and would like to believe I know how it's done ;-)

> There is an inherent difference between CCDs and most
> other chips in that the CCDs are essentially all the
> same element repeated across the surface

So are memory chips, as well as any other video input or output device.

> (pixels
> formed from tiny light-sensitive capacitors) and not a
> complete multi-layer electronic unit formed of
> transistors, diodes, etc, to perform some specific
> function.

That's not what a CCD is.  A CCD is an electrode placed on and insulated
from a p-type silicon substrate.  A CCD is a semi-conductor (a capacitor is
not).  A BBD (Bucket Brigade Device) is a series of capacitors, with
switches (typically FETs or bipolar transistors).  They are not the same as
a CCD.