Patent ID: 9530610
Filing Date: 2016-12-27
CPC Classification: H01J

Claim Text:
1. A method for fabricating a blanking aperture array device for multi-beams comprising: forming, using a substrate over which a first insulating film, a first metal film, a second insulating film, and a second metal film are laminated in order from a lower side, a plurality of electrodes and a plurality of pads on the second metal film; removing a part of the second metal film by etching; removing the second insulating film by etching using, as a mask, the plurality of electrodes, the plurality of pads, and a remaining part of the second metal film; and forming a plurality of openings, each of which is in a position between a pair of electrodes in the plurality of electrodes, and is penetrating the substrate, wherein, when removing the part of the second metal film by etching, the second metal film is etched such that some part of the second metal film remains in a plurality of regions each connecting one of the plurality of electrodes and one of the plurality of pads, and when viewed from above the substrate, a region in which a whole of the plurality of openings having been formed except the plurality of openings themselves is configured by the plurality of electrodes, the plurality of pads, the first metal film, and the second metal film such that an insulating film is not exposed.