Meaning
Database standard structures store graphical representations of integrated circuit layouts for semiconductor manufacturing. The GDSII format remains the industry standard for transferring layout data between design tools and photomask fabrication facilities. It uses a binary file system to define the geometric shapes that represent the circuit layers.
Data Representation
Geometric shapes are organized into hierarchical structures called cells to represent complex electronic circuits. The GDSII format describes these features using polygons and paths on numbered layers, representing the actual silicon regions. This structured representation allows designers to build reuse blocks for repetitive circuit elements.
Manufacturing Handover
Fabrication facilities use this layout file to generate the photolithographic masks required to build the chip. Transferring the GDSII format file represents the final checkpoint where the design phase ends and the physical manufacturing begins. This handover is preceded by physical verification checks to ensure the geometry is buildable.
These checks confirm that the design does not violate the foundry’s manufacturing tolerances.
Legacy Challenge
Design complexity has increased beyond the limits of older file formats. The GDSII format lacks features like compression, which results in files of extreme size for modern chip architectures. This limitation has led to the adoption of newer formats for complex layouts.
