Thread: difference between database grid and manufacturing grid?

recently I noticed in my tech file, it stated as follows,

0.001 Database Grid (for 3rd party tools)
0.01 Manufacturing Grid size and snap spacing

what's the difference between database grid and manufacturing grid? how can i set grid in layout then?

thanks...

Originally Posted by coffeelox

0.001 Database Grid (for 3rd party tools)
0.01 Manufacturing Grid size and snap spacing

what's the difference between database grid and manufacturing grid? how can i set grid in layout then?

3rd party tools should be applicable to any process size, hence their calculation resolution is rather high. In order to enable the presentation of their results (e.g. polygon generation), it's usually recommended to use a Database Grid with high resolution. In such case I'd suggest to set the minor grid size to the Database Grid size, the major grid size to the Manufacturing Grid size, and the snap spacing to either the Manufacturing Grid size or to (2 * Manufacturing Grid size). In the latter case you always have the chance to correct a rounding error by temporarily setting the snap space to (1 * Manufacturing Grid size).
During streamOut (GDSII generation), all data points will be set to the next Manufacturing Grid point.

Thanks a lot...

Manufacturing grid is determined by the smallest geometry that a
semiconductor foundry can process. All drawn geometries during physical
design must snap to this manufacturing grid.

Routing grids or tracks are used by physical synthesis and place-and-route
tools during detail routing. The routing tracks can be grid-based, gridlessbased,
or subgrid-based.