OPC method for graphic structure with different graphic density ends

Abstract

The invention discloses an OPC method for a graphic structure with different graphic density ends. The method comprises the following steps: 1, finding out the graphic structure with different graphic density ends on a layout, wherein the graphic structure has a first dense end and an isolated end; and 2, changing the graph of the graphic structure to change the isolated end of the graphic structure into a second dense end; 3, adding a cutting layer pattern, wherein the cutting layer graph is used for cutting off the added graph outside the isolated end in a second dense end; and 4, performing OPC correction on the graphic structure after the step 2 and the cutting layer graph respectively. According to the method, the graph size control difficulty of the graphic structure with different graph density ends can be reduced, so that the consistency of the graph sizes is improved.

Description

technical field [0001] The invention relates to a semiconductor integrated circuit manufacturing method, in particular to an optical proximity correction (Optical Proximity Correction, OPC) method for pattern structures with different pattern density ends. Background technique [0002] With the continuous development of semiconductor technology, the integration of design layout is getting higher and higher, the critical dimensions are getting smaller and smaller, and the requirements for controlling the size of key layers are becoming more and more stringent. Due to the complexity of the layout, the amount of compensation required after lithography and etching for graphics in different structural environments is not the same. In order to ensure the accuracy of size control, it is necessary to collect a large number of graphics lithography and etching with different size spacing. The final size value is compensated by OPC. [0003] In the actual layout, there usually exists ...

AI Technical Summary

Problems solved by technology

[0003] In the actual layout, there usually exists a graphic structure composed of long line graphics such as the graphic structure in the middle connection layer (MD). The long line graphics of this graphic structure will not be aligned due to different lengths, which will make the long lines One end of the graph is in the dense (dense) graph distribution area, while the other end is in the isolated (iso) graph distribution area, that is, the graph structure will have both a dense end and an isolated end, and the graph distribution density of the dense end and the isolated end is different. , the sum of the line width and spacing of each graphic is different. It is difficult to control the size of the graphics located at the dense end and the isolated end. It is often difficult to ensure the consistency of the size of this type of graphics through size compensation, especially when the graphics are from dense graphics. Graphics size control in the area where the distribution area transitions to the iso graphics distribution area becomes a difficult point

Images