Research On New Extraction Algorithm Of Image Layout

With the development of semiconductor industry, very large scale integration circuit(VLSIC) arises at the historic moment with the development of nanotechnology.At the moment of component towards miniaturization and circuit scale towards integration, layout optimization is becoming increasingly important as the link between layout design and the processes. Since most nets of CIF layout and the real defect outlines in the manufacturing process are irregular shaped in the actual layout optimization, layout optimization of random defects with the aid of image layout will be more effective, so the extraction of image layout from CIF layout becomes the necessary path to solve the problem of layout optimization.According to actual large scale integration circuit(LSIC) layout characteristics, this paper will propose two extraction algorithms to realize visualizing for larger and large scale CIF layout.For larger CIF layout, the new extraction algorithm based on sliding window defines the rectangular range of basic primitives, the rectangular range of CIF layout, the location of sliding window and the slide rule of sliding window. This algorithm realize multiple output by controlling the slide of output window in CIF rectangle range so as to get the complete extraction of larger CIF layout. At the same time, the new algorithm can extract the number of nets, the time of extraction and the number of image layout while extraction, all this results lay a strong foundation for the further layout optimization.Compared with the existing extraction algorithm, this algorithm can solve the problem of complete extraction from larger CIF layout and has the advantages of accurate parameters and transparent extraction processes.Large scale CIF layout has high data volume, the extraction time is rapid growth with the growth of data quantity. The new extraction algorithm based on judgment model gives the judgment model between basic graph of CIF layout and output window. It will chooses effective data by the positional relation and skips the invalid data before processing so as to reduce the time of invalid data processing. The new extraction algorithm reads data in chunks and outputs image layout with multiple ports while processing the data of large scale CIF layout. In terms of data read, block read is instead of whole read or read line by line to minimize the times of data exchange between internal and external storage so as to shorten the time of data reading. In terms of image layout output, multiple ports output is instead of single port output to reduce the the number of CIF file opens so as to shorten the time of file processing. The extraction on experimental layouts and Open SPARC circuits show that this new extraction algorithm not only has the higher efficiency extraction of large scale CIF layout but also has the advantages of higher stability, good portability and easy extension.