A base member includes a lower portion and a lateral portion. The lateral portion includes a first lateral surface, a second lateral surface not adjacent to the first lateral surface, and a third lateral surface adjacent to the first lateral surface, and first to third step portions. The first step portion is arranged inward of the first lateral surface along a portion or an entirety of the first lateral surface, and has a first upper surface provided with a wiring pattern. The second step portion is arranged inward of the second lateral surface along a portion or an entirety of the second lateral surface, and has a second upper surface provided with a wiring pattern. The third step portion is arranged inward of the third lateral surface along only a portion of the third lateral surface, and has a third upper surface provided with a wiring pattern.