Anon (no.delete@this.thanks.com) on June 27, 2022 3:34 am wrote:
> Groo (charlie.delete@this.semiaccurate.com) on June 26, 2022 9:39 am wrote:
> > It is a tad more expensive but not a significant cost in relation to a finished wafer on a modern
> > process. The biggest reason you don't want to do it is the loss of edge area for I/O.
>
> I guess the obvious answer to that would be triangular dies? They still tesselate
> nicely, but they give you higher edge area for a given die size.

I was under the impression that the structures etched into the wafer are aligned with the silicon crystal lattice?

I believe silicon crystallizes as a face centered cubic lattice. That would be compatible with some cartesian 2D grid on the wafer surface (i.e. the usual right angles and rectangles), but not fully compatible with a honeycomb/hexagonal grid[*].

Octagonal would fit better with the crystal; that is, horizontal and vertical as usual, plus the two 45 degree diagonal directions. While you cannot tile the plane with regular octagons, there is a semi-regular grid that would fit the capabilities of the laser cutter that Groo described. Start with any regular grid of square cells; then add all diagonals to all squares, and you get a new square grid, smaller and rotated by 45 degrees. Repeat to reach a desired granularity/resolution.


[*] unless you take those cubes and stand them on a corner, to get a regular hexagon as an "equator".

Okay, enough useless wise-cracking for one post. :-)