Final Testing

So what I'm doing is to show you here one of the very early varieties of devices. that we started with that we still supply to customers which is CCD 02's. Compared to what you're interested in these are very small and they sit in a little camera head like that and I'll show an image on the screen in a moment

And what are these CCD's used for now?

Some are used for astronomy, some are used for cameras, and scientific applications like spectroscopy. We pump it out and insert liquid nitrogen through, ok, so it's under vacuum.

So you get all the air out basically. Yes.

This is called a test camera, we have a test chart up on it.

So we can see what an image looks like.

 I just have to tell the program what I'm looking at.  So I am initizling it now to tell it what to do. You'll get a test chart image similar to this in a mon.   If this is right we should get a test chart image. Which gives us the first look at what a chip looks like in a package.

This is the first level of testing that you do?

When it's actually in a package. You can see it's showing a few columns and is very dark. It needs to get cold. 

Oh I see.

This is what it looks like sorta at room temperature. We have a wait a while for it to get cold. And then we will gradually see the test chart appear. So that's one of the smaller variances it will be improved the longer we go.
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Final Testing :: Laser Testing

Currently I'm sorta checking the beam uniformity of the laser beam itself. This is a cross section of the laser beam. At the moment you can see its scale. It's slightly high here and low here. And I am using a few camera systemswe got to check that uniformity and try to improve it. The laser is being used to anneal the back surface of the CCD wafer after it has been implanted with the boron. That mainly reactivates the surface and allows you to get an image out of it.


The beam itself is about 4 mil squared just a little bit under. And the wafer itself is 5 inches. So you can imagine we have to shoot this little laser beam hundreds of times in line. and then sorta scan it up a row and going across again.

The laser is situated underneath here. and it's an exmi laser 248 nm. There's a mirror it bounces off comes up this black tube, through a few optics in here. There's an attenuator box here which allows us to vary the energy that we get out of the laser. Through some more optics which quantify the size and the beam protocol. And then it goes out into the cabinet


This is our laser stages. This is my camera setup which I am using to do bits and bobs of experiments with. A wafer will evidentially sit on a vacuum chuck like this one and that sits up on the actual frame here. The stage moves across and tells the laser when to fire. 

You can just see this very faint pattern on the chuck. So each one of these small little squares is a laser shot. So it will shoot one, move across, shoot another one go across in a row stop, go onto the next row. And it will do 17 passes forward and back of about 34 shots in length all the way across the wafer. And that's one whole array. Then it will offset from the first shot it did in the left-hand corner by a fifth of a square And do another whole pass. Which will eventually blend each individual shot in. So you don't get any uniformity defects rather than shooting a single shot you'll see it here in the image area. So we blend them in against each other.

The laser beam is at the end of the aperture. We have a focal distance that we know the wafer has to be and that's when you get it to focus when you see the spool. If it was too far back or too far forward you'd have blurred spots and it would not anneal at the right density and the right energy. We can adjust the stage forward and back when we have other measurements we have to take