TSMC Kicks Off Volume Production of 7nm Chips

Re:TSMC Kicks Off Volume Production of 7nm Chips by neltnerb on Tuesday April 24, 2018 @10:21PM (#16918231)

The problem is that it is a single crystal of silicon. To keep it atomically flat you cannot cut it at any angle. You must cut it across the axis the crystal grows in or the surface will be rough and the wafer will likely crack in half in a stiff breeze.

I suppose you could go for some more on-axis cuts, but the crystal planes are pretty restrictive on what you can do. You'd end up having super long and narrow pieces and such.

http://www.crystal-scientific.com/xtal_orientation.html

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Re:TSMC Kicks Off Volume Production of 7nm Chips by tropo on Tuesday April 24, 2018 @11:46PM (#16918503)

The orientation is determined by the seed crystal. You can choose whatever you want.

There will of course be long and skinny pieces. These will be much easier to recycle than the unused portions around the edge of a circular wafer; they need not leave the facility that cuts the wafers.

The end result is rectangles of a standard size in one dimension and varying side in the other dimension.

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