Chip manufacturing

[tnt]

Hi,

If I understood correctly, some of the cost optimization comes from manufacturing more chips per wafer.

I was wondering if they were manufactured with the exact same caracteristics ( 65nm / 1GHz clock ) and just more per wafer (larger wafer ?) or if they were going to be smaller technology.

In anycase, waiting for pictures of the die in high res :p

Cheers,

Sylvain

[Gedece]

Usually, test models are made in lower resolutions to be able to have good distanced connections for hardware tests and design. Then the production model gets miniaturized. This is done to increase the chips per waffer, but also to reduce voltage and power consumption of the chips.

[aolofsson]

DSC00003.JPG (1.34 MiB) Viewed 27914 times

The short answer is that the mass produced parts will be exactly the same design as the low volume 65nm 16-core prototypes we have in place today. This way we minimize project risk.

Getting nice high res pictures is actually a bit of a challenge. We use nine metal layers on our chip, with the top layer being dedicated to supplies. Unless we etch away the toplayer, the picture will just look like a boring plate of metal and not at all like the fancy die shots you would generally see from BigCo. We could go ahead and spend some money/time to get it done, but that will have to wait. In the meantime, here is a picture of our 16-core wirebond package (with the die in the middle).

[tnt]

Thanks for the picture, looks pretty What size is the die ? like 2x2 mm ?

Ok makes sense to minimize risk, especially with the NRE cost in chip fab.

wrt to the metalization layers, yes, I hadn't thought of that. Or maybe the fab itself takes pictures as part of some sort optical inspection or during the first runs ? In anycase, I agree that it's not really a high priority item

[9600]

Andreas found some layout images for the 64-core chip and I've just uploaded these to Flickr:

http://www.flickr.com/photos/parallella ... 545609556/

[tnt]

I've also seen http://www.flickr.com/photos/parallella ... hotostream on that photo stream that I missed before, which I assume is a E16G3. The 'core' itself seems different than the one in http://www.flickr.com/photos/parallella ... 545609556/ though.

[aolofsson]

[notzed]

A little OT - I know a 1c coin from USA means something to a certain proportion of the world population, but an idea for a prop for future 'size' shots might be a metric ruler?