A pattern creation method, including laying out data of a most extreme end pattern of integrated circuit patterns on a first layer and laying out data of the integrated circuit patterns excluding the most extreme end pattern on a second layer, extracting data of a first most proximate pattern being most proximate to the most extreme end pattern from the second layer and converting the extracted data to a third layer, generating data of a contacting pattern which contacts both the first most proximate pattern and the most extreme end pattern in a fourth layer, generating data of a non-overlapping pattern of the contacting pattern excluding overlapping portions with the most extreme end pattern and the first most proximate pattern in a fifth layer, extracting data of a second most proximate pattern being most proximate to the non-overlapping pattern and converting the extracted data to the first layer.