A microscopic projection or a characteristic pattern are formed in the vicinity of a region to be processed before processing using electron beam CVD, during processing an image of a region containing the projection or pattern formed by electron beam CVD is captured to obtain a current position of the projection or pattern, a difference between the position before staring and the current position is treated as a drift amount and processing is restarted at a region that has been subjected to microscopic adjustment of the electron irradiation region.