Improved Hughes Module Zoom Test - Almost 100MP

[abem]

Here's an improved zoomable ultra high res image of a Hughes module:
http://www.timetrafficker.com/test/zoom/

This started life as a 4 by 4 matrix of 12 megapixel images (192 megapixels) that was stitched into one big 150 megapixel image, then downsampled to the 67 megapixel image that you see above. To deploy it on the web, the image was chopped up into almost 1500 256x256 pixel tiles that are served up on demand as you zoom or pan around the image.

You can see things like a failed wire bond underneath the main chip that needed to be done over. You can also see each and every trace on the Hughes chip clearly. At this magnification, the edges of the LED display dies look pretty ragged.

To see this as a full screen cinematic experience, click the "full page" button in the lower right hand corner of the window and then hit F11 to make your web browser go full screen.

-abe.

[retroleds]

Those are great photos Abem. Amazing as it is, that is only about the same level of detail we get with the naked human eye and 40-50X magnification. Very hard to work on things at that magnification level - 20-30X has most people feeling like their hands belong to a Parkinson's sufferer. I'll examine things at 40X (I have 10, 20 and 40 available on my microscope) but rarely work above 20X. Take a piece of human head hair(that will usually be between .002-.003"/.051--.076mm and lay it next to a wire bond(roughly .001"). F'n hair looks comparatively huge.

[abem]

Ed,

Makes it hard to believe that humans performed the wire bonding, doesn't it? Does anyone know exactly how that was done - I assume under a stereo microscope, but does anyone know how the wires were actually manipulated? I noticed that each wire bond tends to have a little spot of metal next to it where it was applied to the module traces. Anyone know why that is?

One other thing - I was looking for a used stereo microscope (preferably zoom) for looking at all sorts of stuff (not just watches). If anyone has any suggestions I'd be glad to hear 'em. I currently leaning towards a Nikon SMZ-1 (7 - 30x) but there are a few other models that I'm also looking into. I was hoping to find something in the neighborhood of $300.

-abe.

[retroleds]

The wire bonding could be totally done by hand - manual machines come up on ebay almost every week(generally $3.5k-$12k, depending). WAS largely done by hand, with different levels of automation(or none). Here would be the manual procedure(roughly):
Basically imagine a stereo microscope with specimen area(work bed) that can be moved in two planes(3 on a better machine). So, module is dropped onto a fixture that gets it within .030-40"(say 1 mm). At that point the operator cranks the handles around to get the table so the first point lines up with their "crosshairs" in the microscope. At that point both crank handles are zeroed for easier math. At that point it is merely a matter of moving from point to point following a chart of the proper stopping point along the X & Y axis. The wire-bond wire comes on a spool, and is essentially spot welded to the trace. The operator on a totally manual machine could slowly bring the head down the last .10-15"(.3.5mm),spark, lift the head and crank to the attachment point for the other end, spark and snip the wire in one motion.

These machines, even the manual ones, are infinately better than what they had back in the day. http://www.westbond.com/machines.htm#manual_die

Ebay has lots of nice stereo microscopes. The Amscope brand isn't fancy, but at less than $300, they are the ticket. The microscope cameras are where you will probably find more frustration in finding one that suit you.

[bruce wegmann]

I have been using a Bausch & Lomb StereoZoom for many years. Check out items No. 130336116466 and 290568942075 on eBay...there's your scope and stand within budget, and perfect magnification range for visual work. If you need to get in tighter, there's the 2x Magnifier that doubles the mag (330567480623), $50. For the price, I don't think there's anything out there better...

[abem]

Ed and Bruce,

Both appear to be good suggestions. At first I was leery of Amscope because of the way they spam the eBay listings, but reviews of the Amscope models seem to be quite positive. We used to use Bauch and Lomb models like this in high school and yeah, they were pretty nice. It looks like there's a lot of nice lab equipment being sold off on eBay so I'm inclined to be patient and pick up something used (I just missed a Nikon SMZ-1 with working ringlight for under $200 - #110689333809). I suspect that these are probably all pretty nice 'scopes. Certainly any of these choices would be better than what I have now (loupe and camera with macro lens).

Thanks for the help.

-abe.

[f.e.a.r]

The wire-bond wire comes on a spool, and is essentially spot welded to the trace. The operator on a totally manual machine could slowly bring the head down the last .10-15"(.3.5mm),spark, lift the head and crank to the attachment point for the other end, spark and snip the wire in one motion.

ed, i read on the forum once that the wire bond was fixed onto the trace by a means of vibration? ive ran a search for the thread but cannot locate it, maybe it was j thomas who said it, he has deleted his posts. anyway, is this correct?

[rewolf]

ed, i read on the forum once that the wire bond was fixed onto the trace by a means of vibration? ive ran a search for the thread but cannot locate it, maybe it was j thomas who said it, he has deleted his posts. anyway, is this correct?

Ultrasonic welding.
Yes, I also believe it was JThomas who had written sort of an essay about the "early days".

[retroleds]

I honestly never delved that deeply into the actual attachment methods they used, since it is not available to me - short of buying a wire-bonder(which I have never been able to justify). Just did this search and came on an excellent article that pretty much explains all the techniques commonly used. Makes sense that an electro-resistance melt of the wire was out of the question. So I guess "spark" would be wrong - maybe "touchdown", liftoff, "touchdown " would be more like it. Darn, I have to keep doing this with silver epoxy.

http://nepp.nasa.gov/wirebond/Basic%20Info.htm

Microscopes: The B &L looks like a solid item, but the Amscope(and Variscope, same thing) are a solidly builtv (Chinese, of course) item. Above and below specimen lighting built in. For the careful "watch enthusiast" , they are hard to beat at $150-225.

the contributions of an individual who decided to blow himself, and his [erstwhile] contributions up. Neither exists in any useful frame of reference, other than our memories. I'll start a wire-bond thread, for posterity. I promise I won't destroy the thread in a hissy fit.
http://www.urbandictionary.com/define.php?term=hissy+fit