Abstract: A photomask with a dummy pattern is inspected in a predetermined detection sensitivity by using photomask pattern data designating a photomask with a dummy pattern to detect defects in the photomask. Coordinates indicating the positions of the defects are also determined. The defects in a design pattern area and those in a dummy pattern area are discriminated by using defect-discriminating data. The defects in the design pattern area and those in the dummy pattern area are examined on the basis of respective inspection specifications.

Abstract: An IC element layout data displaying system includes a magnetic disk unit for storing IC element layout data, and a preprocessor capable of reading the IC element layout data from the magnetic disk unit, of dividing the IC element layout data into a plurality of pattern sets each having an optional number of successive pieces of graphic information on the basis of the IC element layout data in the IC element layout data, and of generating map information including position information representing respective positions of pattern sets. A pattern retrieving unit accesses the IC element layout data by using the map information generated by the preprocessor to obtain graphic information corresponding a display area specified by an input unit. A display unit displays the graphic information retrieved by the pattern retrieving unit.

Abstract: A photomask with a dummy pattern is inspected in a predetermined detection sensitivity by using photomask pattern data designating a photomask with a dummy pattern to detect defects in the photomask. Coordinates indicating the positions of the defects are also determined. The defects in a design pattern area and those in a dummy pattern area are discriminated by using defect-discriminating data. The defects in the design pattern area and those in the dummy pattern area are examined on the basis of respective inspection specifications.

Abstract: An IC element layout data displaying system includes a magnetic disk unit for storing IC element layout data, and a preprocessor capable of reading the IC element layout data from the magnetic disk unit, of dividing the IC element layout data into a plurality of pattern sets each having an optional number of successive pieces of graphic information on the basis of the IC element layout data in the IC element layout data, and of generating map information including position information representing respective positions of pattern sets. A pattern retrieving unit accesses the IC element layout data by using the map information generated by the preprocessor to obtain graphic information corresponding a display area specified by an input unit. A display unit displays the graphic information retrieved by the pattern retrieving unit.

Abstract: Databases are prepared for data of circuit parts to be used in designing ASICs. Each part data contains functional element indicative of kinds of devices and connection information of the devices, a characteristic element indicative of operational characteristic values for the devices, and structural element indicative of sizes and shapes of the devices and terminal positions of the devices. By extracting and synthesizing these elements, new part data can be generated. For example, elements are extracted from part data A by a process P1 and elements a1 to a3 are obtained, and elements are extracted from part data B by a process P2 and elements b1 to b3 are obtained. The elements a3, b2 are synthesized by a process P3, and new part data C is generated. The executed processes P1, P2, P3 are stored in a memory in addition to the part data A, B, C. When the part data A is revised, the stored processes P1, P3 are read to recognize the part data C needs the revising.