Open Artwork System Interchange Standard

Open Artwork System Interchange Standard (OASIS) is a language used by computers to represent and express an electronic pattern for an integrated circuit during its design and manufacture. The language defines the code required for geometric shapes such as polygons, rectangles and trapezoids. It defines the type of properties each can have, how they can be organized into cells containing patterns made by these shapes and defines how each can be placed relative to each other.

OASIS is the purported commercial successor to the integrated circuit design and manufacturing electronic pattern layout language, GDSII.

GDSII had been created in the 1970s when integrated circuit designs had a few hundred thousand geometric shapes, properties and placements to manage. Today, there can be billions of shapes, properties and placements to manage. OASIS creators and users have claimed what the growth of workstations data storage and handling capabilities was far outpaced by the growth of Integrated Circuit layout complexity. Therefore, OASIS tries to solve the purported problem of the large size of the GDSII files by introducing a complicated types of the geometric shapes (25 types of trapezoids only) to reduce the data size. Also, variable-length numeric format (similar to Run-length encoding) for coordinates was implemented. Finally, each cell in the OASIS file can be independently compressed by the gzip-like algorithm.

The effort to create the OASIS format has started in June 2001. The release of version 1.0 took place in March 2004. Its use required the development of new OASIS readers and writers that could be coupled to design and manufacturing equipment already equipped with GDSII readers and writers. Its adoption was born out of a concerted effort by integrated circuit design, equipment, photomask, fabless, 3rd party Intellectual Property (IP) and manufacturing companies from the United States, Japan, Taiwan, Korea and Europe.

A constrained version of OASIS, called OASIS.MASK, addresses the unique needs of semiconductor photomask manufacturing equipment such as pattern generators and inspection systems. Both OASIS and OASIS.MASK are industry standards.

Below is a human-readable text representation of the OASIS binary file that allowed the expression of the above "top" cell view called "Placed_shapes_and_cells_within_an_IC_cell". The top cell is defined by a file-level standard PROPERTY record named S_TOP_CELL. The PROPERTY record below references a PROPNAME record (refNum=0) that has a propname-string called S_TOP_CELL. The top cell contains the placement of three cells called "bottom cells". Bottom cells contain geometric shapes only.

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