Introduction

Artwork Conversion offers two useful translators for SolidWorks designers who need to make masks for either printed circuit boards (PCBs) or for integrated circuits: STL2GBR which translates STL files into Gerber for photoplotting and STL2GDS which translates STL files into GDSII for high resolution masks used in the IC industry.

Why STL?

Why use STL when SolidWorks can export DXF and there are already DXF to Gerber and DXF to GDSII translators?

It turns out that the DXF file produced by SolidWorks are generally not useful for producing a two dimensional mask. Much of the reason is that the DXF file format does not support the concept of "holes" or "voids." Therefore the resulting contours expressed in DXF do not differentiate between a contour that represents a filled region and one that represents a void.

STL, on the other hand, is a simple but complete description of a 3D body done by convering the surface of the body with triangles.

How They Work

Both of our STL translators work by "slicing" the STL body (along a user specified X,Y or Z plane at a user specified depth) and converts the resulting contours into either Gerber or GDSII as needed by the mask making equipment.

Our boolean engine is smart enough to deal with the contours that are filled and contours that are voids and to translate that information correctly into Gerber or GDSII formats.

STL to Gerber - produce mask data for PCB photoplotters.

STL to GDSII - produce mask data for IC mask writers and equipment.

New - Importing Gerber/ODB++/GDSII/3Di into SolidWorks

Our customers in the EDA and microelectronics industries have requested us to find a way to import 2 1/2 D layout data into SolidWorks.

We started this project several months ago but it has turned out to be much harder than we originally anticipated. The SolidWorks API is not optimized for import of a large number of elements and we have had to work around a lot of issues.

However we believe we have arrived at a useful importer.

How it Works

The block diagram below summarizes our approach:

Any EDA data to import must be first "conditioned." This involves creating clean contours of overlapping data, correcting any illegal (i.e. self intersecting shapes), and assigning to each layer a height and thickness since we are essentially extruding a 2D series of layers into a 3D body.

The output of the conditioning software is a file format known as 3Di. Artwork developed this format in 2004 in order to model IC packages in 3D. It supports multi-layers, vias, wire bonds and solder balls.

Once in the 3Di format, Read3Di, a SolidWorks plug-in, brings the data into SolidWorks.

More Info ... Read3Di Datasheet