A small-pixel CCD project

[John Geary]

Posted to CCD-world:
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At 12:14 PM 1/11/98 EST, you wrote:
>Posted to CCD-world:
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>*****jj
>
>John,
>
>FYI . .. the only small pixel Sandbox device that comes close to what we have
>developed is the 2k(V) x 1k (H), 9-micron backside illuminated CCD packaged in
>a PCB. It uses four dual-stage amplifiers for 30 frame/sec operation. Slow-
>scan noise is relatively high at 3.5 e- rms (Ts = 4 micro-sec) and a full well
>of 70,000 e- (non MPP).  The CCD was built on Sandbox III. However, devices
>need to be built on 10-micron , 50 ohm epi material in the future (MTF
>problem). 
>
>There are six other formats on Sandbox V (Spectra series) to be built... the
>largest being 4k (H) x 1k (V) .. . however, these are all 12 micron pixels
>(LEDIT designs).  A 4k (V) x 4k (H), 9 micron pixel is in the design phase
>(Sandbox IX). 
>
>Why do you need to butt 8-micron pixels? Even a 4k dimension is small enough
>to come up with decent yield (famous last words).
>
>What is your diving record now? Are you going to sneak in a dive with the
>upcoming eclipse? Jeff says he is going after your record next month.
>
>Jim Janesick

Hi Jim,

The reason for the 4K (V) X 1K (h) partitioning is because of diffentential
tracking required for drift scanning on a wide Schmidt camera field.  Each
narrow field needs to be individually clocked in the vertical direction to
approximate the local sidereal rate.

The issue of defocuss for backside-illuminated small pixels is of course
nontrivial.  Thinning to 10u or less on hi-res material will help, plus
there may be a special tweak called "Hi-CTF" (details unknown to me) that
Sarnoff believes can produce less than 20% crosstalk on these small pixels.
But it is a concern.

The Curacao Eclipse Dive:  I was so looking forward to it, but just this
week I was informed that my father is scheduled for very extensive and
life-threatening surgery that week (last week of Feb).  So, it looks like I
will not be going.  Am looking for a replacement couple for this very
special diving/eclipse holiday.  Contact me at geary at cfa.harvard.edu if
anyone is interested.  Jim, can you contact Jeff pinter and have him give me
a call at (617)495-7431?  I have some travel info for him.

--John Geary
geary at cfa.harvard.edu

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