Multi charged particle beam writing apparatus and multi charged particle beam writing method

A multi charged particle beam writing method comprising:

• passing a charged beam through an aperture plate to form multiple beams;
• passing the multiple beams through a blanking plate having a plurality of openings;
• providing a plurality of first blankers on a lower surface of the blanking plate around each of the plurality of openings in the blanking plate, each of the plurality of first blankers being arranged around a different opening in the plurality of openings and each of the first blankers being separately operable to deflect one of the multiple beams passing through the corresponding different opening in the plurality of openings;
• providing a plurality of second blankers on an upper surface of the blanking plate around each of the plurality of openings in the blanking plate, each of the plurality of second blankers being arranged around one or more openings in the plurality of openings and each of the second blankers being separately operable to deflect one or more of the multiple beams passing through the one or more openings in the plurality of openings;
• performing blanking control separately with regard to each of the multiple beams using each of the plurality of first blankers;
• detecting a defective beam in multiple beams having passed through one of the plurality of openings;
• commonly deflecting, by one of the plurality of second blankers, the one or more of the multiple beams corresponding to the one of the plurality of second blankers to prevent the one or more of the multiple beams from reaching a target object, the one or more of the multiple beams including the detected defective beam;
• and
• performing multiple writing while executing position shifting such that positions of the detected defective beam in the multiple writing are not located at a same position, and while individually performing the blanking control with regard to the each of the multiple beams.