GDSII

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GDS II stream format, commonly known as GDSII is a database format, which in the integrated circuit industry has been the de facto standard for IC layout data exchange for more than two decades. Originally it was developed by Calma for that company's layout design computer systems "Graphic Data System" ("GDS") and "GDS II". Now the format is owned by Cadence Design Systems.

GDSII - Gerber Data Stream Information Interchange.

It is a binary format for representation of planar geometric shapes, text labels and some other information in hierarchical form. The objects are grouped by numeric attributes assigned to them: "layer number" and optional "datatype" or "texttype". While basically these attributes were to correspond to the "layers of material" used to manufacture an integrated circuit, very soon their meaning had become more abstract, reflecting the way that the physical layout of a circuit is being designed.

Originally it was designed as a format of data files used to control integrated circuit photomask plotting. Despite its limited set of features and low data density, it was ubiquitously used for transfer IC layout data between design tools from different vendors which operated with proprietary data formats.

GDSII files are considered to be the final output of the IC design cycle and are passed to IC foundries for IC fabrication. These GDSII files were originally produced on magnetic tapes, hence the final moment of the IC design process became known as tapeout.

As of October 2004, many EDA software vendors have begun to support a new format, OASIS, which may replace GDSII due to higher data density. It has been claimed that the OASIS format is between 10 to 50 times more efficient than GDSII.[1]

With the free tools "gds2pov" [2] and POV-Ray [3] you can easy convert GDSII data into a nicely rendered 3D view.