Patent Number: 
Section: claims

1. A mask data generation method, comprising:arranging first and second auxiliary patterns adjacent to a device pattern, andperforming, by a computer, an optical proximity correction (OPC) process,wherein a first distance at which the first auxiliary pattern is spaced from a short side of the device pattern is set to be longer than a second distance at which the second auxiliary pattern is spaced from a long side of the device pattern upon arranging auxiliary patterns. 2. The mask data generation method according to claim 1, wherein:the first distance varies depending upon a dimension of the short side of the device pattern. 3. The mask data generation method according to claim 1, wherein:the first distance is predetermined with a table lookup method by a dimension of the short side of the device pattern. 4. The mask data generation method according to claim 1, wherein:the first distance falls within a range from a minimum dimension to 1.6 times the minimum dimension. 5. The mask data generation method according to claim 1, wherein:the auxiliary pattern spaced from the short side of the device pattern is located a minimum separation dimension away from a position of an OPC pattern obtained by an OPC process without the auxiliary patterns. 6. A mask produced by the mask data generation method according to claim 1. 7. A mask produced by the mask data generation method according to claim 2. 8. A mask produced by the mask data generation method according to claim 3. 9. A mask produced by the mask data generation method according to claim 4. 10. A mask produced by the mask data generation method according to claim 5. 11. A mask data generation method, comprising:arranging first and second auxiliary patterns adjacent to a device pattern, andperforming, by a computer, an optical proximity correction (OPC) process,wherein a first distance at which the first auxiliary pattern is spaced from a first side of the device pattern is set to be longer than a second distance at which the second auxiliary pattern is spaced from a second side of the device pattern upon arranging auxiliary patterns. 12. The mask data generation method according to claim 11, wherein:the first distance varies depending upon a dimension of the first side of the device pattern. 13. The mask data generation method according to claim 11, wherein:the first distance is predetermined with a table lookup method by a dimension of the first side of the device pattern. 14. The mask data generation method according to claim 11, wherein:the first distance falls within a range from a minimum dimension to 1.6 times the minimum dimension. 15. The mask data generation method according to claim 11, wherein:the auxiliary pattern spaced from the first side of the device pattern is located a minimum separation dimension away from a position of an OPC pattern obtained by an OPC process without the auxiliary patterns. 16. A mask produced by the mask data generation method according to claim 11. 17. A mask, comprising:first and second auxiliary patterns being arranged adjacent to a device pattern,wherein a first distance at which the first auxiliary pattern is spaced from a first side of the device pattern is set to be longer than a second distance at which the second auxiliary pattern is spaced from a second side of the device pattern upon arranging auxiliary patterns. 18. The mask according to claim 17, wherein:the first distance varies depending upon a dimension of the first side of the device pattern, and wherein said first side comprises a short side and said second side comprises a long side of the device pattern. 19. The mask method according to claim 17, wherein:the first distance is predetermined with a table lookup method by a dimension of the first side of the device pattern. 20. The mask according to claim 17, wherein:the first distance falls within a range from a minimum dimension to 1.6 times the minimum dimension.