Large gds file

[Sharon Oh]

I am having problems streaming my layout to gds. I have a very simple
unit cell, which is a pcell with just two circles. Within this pcell,
I have set x and y repetition. This generates a lot of circles
(almost
a million polygons) in the final layout. When I export to gds, the
file is large (around 600 Meg). Is this normal? The file is a bit
unwieldy to ftp... is there any way to reduce its size (before zipping
it, that is)?

Sharon

 

[Roger Light]

Sharon Oh wrote:

I am having problems streaming my layout to gds. I have a very simple
unit cell, which is a pcell with just two circles. Within this pcell,
I have set x and y repetition. This generates a lot of circles (almost
a million polygons) in the final layout. When I export to gds, the
file is large (around 600 Meg). Is this normal? The file is a bit
unwieldy to ftp... is there any way to reduce its size (before zipping
it, that is)?

By default, pcells are flattened when they are exported as gds2 (gds2
does not support the notion of pcells). This means your simple pcell
with repetitions becomes a very large layout cell that does not take
advantage of the redundancy of your design.

Would it be possible to simply create a mosaic of your two circle pcell?
Obviously this depends on how your repetition works.

If you can do this, the gds2 file will contain one structure that is
your pcell and another structure that is the mosaic and will hence be
much smaller. Your current gds2 file effectively has a million
structures whereas what I have proposed would have two.

Hope this helps.

Regards,

Roger