Start a new topic

GDSII Export

GDSII Export
1 Comment

I ended up re-drawing the AutoCAD design I previously sent you, removing all the blocks and simplified it. It now imports correctly into FAB 3000, but now the issue is that it does export to GDS correctly. The export takes a very long time (over 30mins) and does not complete correctly, with sections missing.


Thanks again for sending the sample file.

The reason for the long export times is primarily due to limitations in GDS-II:

1. For example GDSII doesn't support "Circles" so during export FAB 3000 must convert all those thousands of circles to polygons.  Each polygon for a circles results in several hundred points.

2.  Secondly GDSII doesn't support Negative Data (i.e. holes inside polygons  for example all those "negative" circles I mentioned), so FAB 3000 must create complex polygons which connect all those"negative objects" to the outermost polygons.  To understand exactly what FAB 3000 must do, try loading simple pattern into FAB 3000 and then use the command called "Flatten Composite" (menu:  Tools | Composite Layers | Flatten... ).  I would recommend before export to GDSII that you first "flatten" the composite.

Note:  Most of your patterns appear that they are repeatable, so I will look to see if there is a way to optimize this data (using MInserts) so it outputs quickly & efficiently.  


3.  The error message you receive when plotting at 2400 DPI, is due to memory limitation - I believe.  That's why it works fine at 1200DPI but not 2400 DPI.  FAB 3000 for Windows is built using 32-bit and I believe a pure 64-bit version of FAB 3000 (V6) would be more efficient.  We do offer FAB 3000 (for Linux 64-bit) for our heavy duty users and it seems to work very well for complex/large designs.  I can send you the binaries for FAB 3000 Linux (if you're interested).
Login or Signup to post a comment