
Inside the Intel 1405: die photos of a shift register memory from 1970 - jekub
http://www.righto.com/2014/12/inside-intel-1405-die-photos-of-shift.html
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kabdib
Lovely stuff. I wonder how close you could get to making this stuff in your
garage now, given a silicon wafer and maybe a vacuum chamber. (I imagine the
etching chemicals would probably make you unpopular with your neighbors...)

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EvanAnderson
She didn't do anything remotely this complicated, but a few years ago Jeri
Ellsworth did do a couple videos of "homemade" ICs.

[https://www.youtube.com/watch?v=PdcKwOo7dmM](https://www.youtube.com/watch?v=PdcKwOo7dmM)

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arbuge
Really interesting how chips haven't changed much for almost 50 years - except
for getting (much) smaller. This could have been a modern die photo except for
the scale of things...

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kken
Uhm no, absolutely not. The basic operational principle remained the same, but
absolutely everything has been changed many times over. Trillions of dollars
were invested to make it happen.

The only constant is probably that it is still made on a silicon wafer. But
even this wafer changed a lot, and I am not talking about its size.

Would you also compare a horse carriage to a Tesla?

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arbuge
The wafer is a slab of polysilicon, and has been that way for a long time.
Most of those trillions you mention were invested to make the lithography
smaller, which is how you get more transistors into the same die.

Edit: silicon, not poly silicon. Not sure why I said poly there...

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kken
No, simply no.

ICs are made of monocrystalline silicon, not polysilicon. There have been
massive efforts to understand how to make it cleaner (internal gettering) and
how to get wafer mechanics under control (Nitrogen doping). That does not even
touch the changes in production technology to go from 10 mm Wafers to 300 mm
Wafers. (You just make them larger, right...)

A lot of new concepts and materials have been introduced to ICs during the
last decades. Especially since the 130 nm ground rule, lithography has not
been the main limiter. Examples: Copper, Tungsten, Diffusion barriers,
Silicide, Strained Silicon, High-k, metal gates, finfet, 3d integration etc...

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kijiki
10 mm wafers? Were they ever that small? I've never heard of less than 1
inch...

