The present invention aims at reducing the number of scanning exposure and at enhancing throughput. the above-mentioned objective is achieved by allowing a substrate 14 to be placed in sideways with respect to a substrate holder 15a (placing the longer sides of the substrate in parallel to the shorter sides of the substrate holder) depending on the size of the apparatus and the size of the substrate 14. It is acceptable even when areas other than an effective exposure area of the substrate 14 should project out from the substrate holder.