In end portions of first and second gate patterns aligned in parallel relation to each other, and opposite end portions of third and fourth gate patterns aligned in parallel relation to each other, the end portion of the first gate pattern extends to be positioned closer to the third and fourth gate patterns than the end portion of the second gate pattern is, and the opposite end portion of the fourth gate pattern extends to be positioned closer to the first and second gate patterns than the opposite end portion of the third gate pattern is.