Explanation of Silicon 'Tape-Outs', Wafers, Chips, etc?

[emilyek]

I'm sort of looking for something more than just a defintion, a little in-depth; maybe some pictures, even.

In my imagination its like a big log of albino taffy being strung out in a clean room, but I'm sure that's probably not right. =p

Anyone got a good link? I could Google myself, but felt a little lazy and social.

 

[emilyek]

So many views and no responses. :/

 

[Tsosczb]

So many search engines, so little queries...

 

[emilyek]

This is true.

I found some...although it wasn't as easy as you might think.

The info is basic at best and the pics are lame, which was disappointing, considering this is the internets and all.

The last link, with the weirdest site, is the best, I think.

http://www.tweak3d.net/articles/howcpusaremade/3.shtml

http://www.extremetech.com/article2/0,1697,1841487,00.asp

http://www.just2good.co.uk/


I guess 'tape out' refers to the actual etching of the wafer, 'tape out' being a carryover term from when magnetic tape was used.

I still wanna know why the wafers are round. Doens't make sense not to make them square.

 

[zephyrprime]

Originally posted by: emilyek
I still wanna know why the wafers are round. Doens't make sense not to make them square.

The reason you didn't get any answers is because so many people here are just hobbiest and not scientists or engineers. Wafers are round because the logs they are sliced from a cylinder. The cylinders are made by chemical vapor deposition around a central core. The log grows outward so even if you started out with a square core, you'd get a mostly round thing. (synthetic sapphires are also grown in big logs too). Being round does lead to some dies being cutoff that reside on the edge of the wafer.

 

[emilyek]

The reason you didn't get any answers is because so many people here are just hobbiest and not scientists or engineers

Yes, I know. Me too.

(synthetic sapphires are also grown in big logs too)

Oh, I see.

 

[oupei]

silicon wafers are crytals and they just grow radially like that. it's like when you made rock candy (aka one big sugar crystal) in middle school. I forget what shape rock candy is in though...

btw, i'm a senior EE at georgia tech, and still i'm not sure of this stuff...

 

[imported_Kensai]

"Tape-Out" = Generally, it's planning/replanning for a failed action.

I'll let someone else find some sites for the others.