Method of forming layout of semiconductor device

A method of forming a layout of a semiconductor device, comprising:

• forming a plurality of first line patterns being long straight lines in each areas, wherein the first line patterns extend along a first direction in a first area and a second area, but the first line patterns extend along a second direction in a boundary area between the first area and the second area, wherein the second direction is different from the first direction;
• forming a plurality of second line patterns being long straight lines in each areas, wherein the second line patterns extend along a third direction in the first area and the second area, but the second line patterns extend along a fourth direction in the boundary area between the first area and the second area, wherein the fourth direction is different from the third direction, so that minimum distances between overlapping areas of the first line patterns and the second line patterns in the boundary area are larger than minimum distances between overlapping areas of the first line patterns and the second line patterns in the first area and the second area;
• and
• performing a trimming process to shade the first line patterns and the second line patterns in the boundary area and the second area.