Lithographic method using variable-area electron-beam lithography machine

1. Field of the Invention A lithographic method by the use of a variable-area electron-beam lithography machine makes use of an electron beam having a cross section shaped into right-angled isosceles triangles. The lithography machine can shape the cross section into the right-angled isosceles triangles or a rectangle. Where a trapezoidal figure to be written has at least one leg (oblique side) making an angle of 45 degrees with the normal to the bottom base, a portion including the 45-degree leg is extracted and written by the right-angled isosceles triangles.