Software for converting DXF files to GDS and performing logical operations
Description:
This software can be used to convert DXF files into GDSII. It is also useful for performing logical operations on layers within a GDSII file. For example, the inversion of the tone of a layer can be performed quite easily using this software.
Note: In cases where L-Edit fails to invert a pattern, LinkCAD will usually work.
Invoking:
LinkCAD is available on all CNF Windows systems... double click the LinkCAD icon on the Desktop.
Capabilities:
Convert between GDS, DXF, bitmap (image) and EPS files
Perform logical operations including: AND, OR, XOR, NOT
Documentation:
AutoCAD allows unclosed polygons, zero-width lines, hatching, more than 200 vertices in a polygon, self-intersecting polygons, but these structures are not supported by the GDS format. If you are converting AutoCAD DXF files to GDS, follow the design rules at the URL below and summarized here:
Rule 1: Use zero-width closed polylines
Rule 2: Don't use hatching
Rule 3: Close open boundaries using LinkCAD's polygon repair feature
Rule 4: Avoid drawing polylines with more than 200 vertices
Rule 5: No self-intersection (boundary crosses itself)
Simple Image Reversal / Tone Reversal example:
Put features on layer 2;
Make a large bounding box on layer 1 around all features;
Read the GDS file into LinkCAD;
Use Tools -> Layer Operations
Specify First Layer to be layer 1 and Second Layer to be layer 2, place result on layer 1
Choose "Subtract 2nd from 1st" radio button
Press START and OK
Continue pressing NEXT button to write output file