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All of the "sensor cleaning" instructions I've found are actually for cleaning the IR low pass filter in front of it. Unfortunately, I've got a tiny bit of tape residue on the actual CMOS sensor of the camera. (Not to worry, this is a $40 camera not a DSLR.) Any suggestions on cleaning off the tape residue?

Thanks!

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  • \$\begingroup\$ How is that even possible, did you forcibly remove the IR filter somehow? \$\endgroup\$ Feb 5, 2013 at 4:13
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    \$\begingroup\$ Buy another $40 camera. \$\endgroup\$
    – MikeW
    Feb 5, 2013 at 4:21
  • \$\begingroup\$ It's intended as a security camera, so it's built without an IR filter. Ironically, the tape residue got on there in the course of adding an IR filter. (I tested the setup by taping the IR cutoff glass inside. It worked great, but, when I was disassembling it to mount the glass more securely, the tape slipped onto the sensor.) I've actually had a good bit of success by gently brushing the sensor with a microfiber cloth. I haven't managed to get the last little bit off this way, though, so I'm hoping someone might suggest a safe chemical to use. Otherwise, I'll just keep rubbing (gently). \$\endgroup\$
    – user16001
    Feb 5, 2013 at 5:08
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    \$\begingroup\$ In that case I'm positive it'll still have a filter/cover over the sensor - even if it doesn't filter the IR. I believe the only time you'd ever be exposed to a sensor without any plastic/glass layer over it would be if you forcibly removed it. \$\endgroup\$ Feb 5, 2013 at 13:00

3 Answers 3

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Apart from filtering IR, one of the IR filter's other main roles is to protect the sensor underneath.

Depending on the technology used, the surface of a sensor is not smooth, so it needs some type of cover, otherwise you would never be able to get dust particles out of the the millions of tiny microlenses on its surface. It just makes sense for manufacturers to make that cover also incorporate the IR and low pass filter. If you've somehow managed to pull off that filter(s) and have dust actually on the surface underneath, I don't think there is any way to clean it without damaging it.

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    \$\begingroup\$ Any mechanical effort to remove the residue is almost certainly going to damage the microlens structure. But go ahead and do whatever you like with the understanding that you have $40 of sunken cost in this. Maybe at best you can see the effect of damaging the surface of a sensor (pix please). \$\endgroup\$
    – Skaperen
    Feb 5, 2013 at 5:20
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I Suspect very, very strongly that you're not trying to actually clean the silicon surface, but merely the cover-glass that is integrated into almost every CCD/CMOS sensor available. If the sensor it truly exposed, you will indeed have to be very careful, as you're likely to damage the bond-wires by contacting them, even with the softest of brushes.

Anyways, if you are indeed just trying to clean the cover-glass on the image sensor package, the method for cleaning the sensor is the same as cleaning an IR-cut filter.

If you actually have a security camera that doesn't have a glass cover integrated into the die package for the image sensor, I would be very surprised.

Can you tell me where you bought it? I have some experiments that would benefit from having access to a bare-die image sensor.

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  • \$\begingroup\$ Yeah, seconded for curiosity where to find naked sensors! What brand camera etc? \$\endgroup\$
    – NULLZ
    Feb 5, 2013 at 11:33
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I have an idea, If you have the time, chemicals, skills and patience...

Remove the CMOS sensor from the camera and make sure there are as few bits attached to it as possible.

Then. I recommend that you try and get some of the tape that was originally got stuck to the CMOS and experiment with the chemicals to see what dissolves it best before you try it on the CMOS. Look for solvent lists like this

When you find a chemical that works, then try and research the chemical interactions between it and polysilicon (note there are many substances on the CMOS sensor so you might have to do a lot of research...)

Using something like acetone, perhaps butane lighter fluid to try to dissolve the (tape-residue)glue Note (If you can get something like compressed butane fluid to work then you could potentially use it to dissolve and blow away the residue)

When you've found something that dissolves the glue then use it, get a bottle of de-ionized water, rinse with de-ionized water, repeat and dry out in a sterile condition if you can.

Try to replace, and test.

Remember, be safe, things like acetone and butane are highly flammable, can be toxic and some more advanced solvents can be carcinogenic.

If you (or anyone else reading this) do this, you have to let me know if it works and how it went down!

Lastly. Its a $40 camera, think of all the fun you're now having with it! :D

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  • \$\begingroup\$ Acetone! Great stuff for removing things like bad photo-resist from your wafer. \$\endgroup\$
    – Phil
    Feb 5, 2013 at 17:15
  • \$\begingroup\$ But can interact with some of the substances in CMOS sensors i believe. Best to test that it works first on any glues! \$\endgroup\$
    – NULLZ
    Feb 6, 2013 at 13:54

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