More info on black silicon
Don Stauffer
> http://www.photonics.com/Content/ReadArticle.aspx?ArticleID=36474&refer=spectraNewsletter&utm_source=spectraNewsletter_2009_February&utm_medium=email&utm_campaign=spectraNewsletter
>
Either the reporter got it completely wrong, or this is a bunch of bull.
The quantum efficiency of regular silicon is 50%. How can you get 100
times more sensitivity? There are already avalanche versions of silicon
diodes, so that wouldn't do it.
The surface treatment can change the "color", but silicon is silicon.
Paul Furman
> RichA wrote:
>> http://www.photonics.com/Content/ReadArticle.aspx?ArticleID=36474&refer=spectraNewsletter&utm_source=spectraNewsletter_2009_February&utm_medium=email&utm_campaign=spectraNewsletter
>
> Either the reporter got it completely wrong, or this is a bunch of bull.
>
> The quantum efficiency of regular silicon is 50%. How can you get 100
> times more sensitivity?
Here's the last time we discussed this:
http://groups.google.com/group/rec.photo.digital/browse_thread/thread/6ab82020f4b5f3a
> There are already avalanche versions of silicon
> diodes, so that wouldn't do it.
>
> The surface treatment can change the "color", but silicon is silicon.
--
Paul Furman
www.edgehill.net
www.baynatives.com
all google groups messages filtered due to spam
Rich
news:49b293ec$0$89386$815e...@news.qwest.net:
> RichA wrote:
>> http://www.photonics.com/Content/ReadArticle.aspx?ArticleID=36474&refe
>> r=spectraNewsletter&utm_source=spectraNewsletter_2009_February&utm_med
>> ium=email&utm_campaign=spectraNewsletter
>>
>
>
> Either the reporter got it completely wrong, or this is a bunch of
> bull.
>
> The quantum efficiency of regular silicon is 50%. How can you get 100
> times more sensitivity? There are already avalanche versions of
> silicon diodes, so that wouldn't do it.
>
> The surface treatment can change the "color", but silicon is silicon.
Maybe it functions like a passive photomultiplier?
Kennedy McEwen
<stau...@usfamily.net> writes
>
>Either the reporter got it completely wrong, or this is a bunch of bull.
>
>The quantum efficiency of regular silicon is 50%. How can you get 100
>times more sensitivity?
Because sensitivity is not the same as quantum efficiency. The former
is related to SNR, the latter to responsivity.
Using internal avalanche raises the effective QE to the point were the
electrons generated by a single photon exceed the noise level several
times over, resulting in more sensitivity.
The same general principle is used in EMCCDs, although in this case the
avalanche gain is in the readout chain rather than in the sensor itself.
The result is devices with sensitivity matching many image intensifiers.
However with the gain in the pixel the speed of device would be much
higher than EMCCDs.
>There are already avalanche versions of silicon diodes, so that
>wouldn't do it.
>
There are, but limited and variable breakdown voltage tends to restrict
the gain well below the levels claimed of black silicon.
I agree, however, that there is a huge amount of hype around black
silicon. It can't, for example, deliver power panels with 100x the
output of conventional silicon solar cells, which I have seen claimed in
some articles.
--
Kennedy
Yes, Socrates himself is particularly missed;
A lovely little thinker, but a bugger when he's pissed.
Python Philosophers (replace 'nospam' with 'kennedym' when replying)
rjn
> Either the reporter got it completely wrong, or this is a bunch of bull.
What SiOnyx actually claims is at:
http://www.sionyxinc.com
And they do claim 100x for photodetection.
They also depict a DSLR on many pages.
Assuming the 10,000% efficiency is true, and could be
delivered as a camera sensor array, and doesn't have
massive IR pollution, I don't see ISO 10000 coming to
a DSLR real soon.
Today's lenses are too fast, and the shutters too slow.
And no one is going to use a 100x ND filter that you
can't see through.
SiOnyx claims they can tune the process. If so,
I can see low-noise ISO 400 and 800 coming to DSLR.
But no happy news for Foveon here, as wiki notes:
"... such as an enhanced absorption that extends to the
infrared below the band gap of silicon, including the
wavelengths for which unmodified silicon is transparent."
--
Regards, Bob Niland mailto:na...@ispname.tld
http://www.access-one.com/rjn email4rjn AT yahoo DOT com
NOT speaking for any employer, client or Internet Service Provider.
Paul Furman
> Don Stauffer <stauf...@usfamily.net> wrote:
>
>> Either the reporter got it completely wrong, or this is a bunch of bull.
>
> What SiOnyx actually claims is at:
> http://www.sionyxinc.com
>
> And they do claim 100x for photodetection.
> They also depict a DSLR on many pages.
That's a Nikon D200 detail on the front page <g>.
> Assuming the 10,000% efficiency is true, and could be
> delivered as a camera sensor array,
http://www.sionyxinc.com/technology.asp
I can imagine that surface capable of absorbing well, it's like black
velvet. I don't get how you'd chop it up into pixels though as the
'hairs' are randomly spread... maybe there's a few hundred of those in a
single pixel???
http://www.sionyxinc.com/thinlayer.asp
Hmm, much thinner silicon is needed so maybe the circuitry goes on the
back side...
http://www.sionyxinc.com/arrays.asp
Yep, that sounds right, this allows very small pixels to perform like
big pixels...
"enhances silicon's detector response by a factor of 100 or more
enabling 1 ľm2 SiOnyx Black Silicon pixels that produce more signal than
36 ľm2 traditional silicon pixels."
Well their numbers are off, DSLR pixels are about 5-10 microns, P&S
around 2 microns... maybe this implies 30MP cell phones with the
performance of high end astronomy sensors? <g>.
> and doesn't have
> massive IR pollution, I don't see ISO 10000 coming to
> a DSLR real soon.
>
> Today's lenses are too fast, and the shutters too slow.
> And no one is going to use a 100x ND filter that you
> can't see through.
>
> SiOnyx claims they can tune the process. If so,
> I can see low-noise ISO 400 and 800 coming to DSLR.
>
> But no happy news for Foveon here, as wiki notes:
> "... such as an enhanced absorption that extends to the
> infrared below the band gap of silicon, including the
> wavelengths for which unmodified silicon is transparent."
>
> --
> Regards, Bob Niland mailto:na...@ispname.tld
> http://www.access-one.com/rjn email4rjn AT yahoo DOT com
> NOT speaking for any employer, client or Internet Service Provider.
rjn
> ...maybe this implies 30MP cell phones with the
> performance of high end astronomy sensors? <g>.
Full color nightvision.
Pin hole cameras could make a big comeback.
Lenses will need to stop down to f4096 or so.
Good bye bokeh.
Hello diffraction.
And, when you aren't shooting, you can point your
camera at the sun, lock up the mirror, and feed
power back into the grid.
If investors weren't running for the hills, SiOnyx
would make a fabulous IPO, or SEC poster child.
Time will tell.
Don Stauffer
That is an avalanche diode.
Don Stauffer
> Because sensitivity is not the same as quantum efficiency. The former
> is related to SNR, the latter to responsivity.
>
> Using internal avalanche raises the effective QE to the point were the
> electrons generated by a single photon exceed the noise level several
> times over, resulting in more sensitivity.
>
Well, sensitivity is a very fuzzy word in EO. QE is well defined. I
think what you are talking about is responsivity, the voltage or current
out per a ceertain irradiance. Okay, I can see a high responsivity for
something that multiplies electrons.
Paul Furman
> Paul Furman <pa...@-edgehill.net> wrote:
>
>> ...maybe this implies 30MP cell phones with the
>> performance of high end astronomy sensors? <g>.
>
> Full color nightvision.
Yep. And super IR performance too.
> Pin hole cameras could make a big comeback.
> Lenses will need to stop down to f4096 or so.
> Good bye bokeh.
> Hello diffraction.
It would start suffering from diffraction around f/2, and hard to design
a lens faster than that so maybe just a pinhole is all you need. No need
to focus then, and no distortion or chromatic aberrations.
> And, when you aren't shooting, you can point your
> camera at the sun, lock up the mirror, and feed
> power back into the grid.
It should charge the battery when you take pictures. Only reviewing on
the LCD would use energy <g>. Shooting in bright sunny conditions would
require opening a steam release valve <g>.
> If investors weren't running for the hills, SiOnyx
> would make a fabulous IPO, or SEC poster child.
> Time will tell.
--
Kennedy McEwen
<stau...@usfamily.net> writes
And that is all black silicon is and claims to be (plus a little bit of
extra absorption, which is where you started from, but it isn't much -
which is also where you started from). The rest IS hype. :-(
Rich
c4a0b7...@w9g2000yqa.googlegroups.com:
> Paul Furman <pa...@-edgehill.net> wrote:
>
>> ...maybe this implies 30MP cell phones with the
>> performance of high end astronomy sensors? <g>.
>
> Full color nightvision.
>
> Pin hole cameras could make a big comeback.
> Lenses will need to stop down to f4096 or so.
> Good bye bokeh.
> Hello diffraction.
>
>
Integrated ND filters.
George Kerby
On 3/8/09 9:10 PM, in article 6Tz07VAo...@kennedym.demon.co.uk,
"Kennedy McEwen" <r...@nospam.demon.co.uk> wrote:
> In article <49b3ea32$0$48225$815e...@news.qwest.net>, Don Stauffer
> <stau...@usfamily.net> writes
>> Kennedy McEwen wrote:
>>
>>> Because sensitivity is not the same as quantum efficiency. The
>>> former is related to SNR, the latter to responsivity.
>>> Using internal avalanche raises the effective QE to the point were
>>> the electrons generated by a single photon exceed the noise level
>>> several times over, resulting in more sensitivity.
>>>
>>
>> Well, sensitivity is a very fuzzy word in EO. QE is well defined. I
>> think what you are talking about is responsivity, the voltage or
>> current out per a ceertain irradiance. Okay, I can see a high
>> responsivity for something that multiplies electrons.
>
> And that is all black silicon is and claims to be (plus a little bit of
> extra absorption, which is where you started from, but it isn't much -
> which is also where you started from). The rest IS hype. :-(
All I know is that it is good stuff for building aquariums. ;-)