Mass distribution measuring method and mass distribution measuring apparatus

A mass distribution measuring apparatus comprising:

• an ionizing beam irradiation unit that irradiates an ionizing beam toward a sample surface on a substrate;
• and
• an ion detection unit that detects information including a mass-to-charge ratio and a detection position of ions generated by irradiating the ionizing beam,
• wherein the apparatus further comprises:
• a direction changing unit that changes a direction of irradiating the ionizing beam to the sample surface;
• an image acquiring unit that acquires a plurality of mass distribution images from each information detected by irradiation from a plurality of incident directions;
• and
• an image synthesizing unit that synthesizes the plurality of mass distribution images, and wherein
• the image synthesizing unit aligns an absolute coordinate at each point on the sample with a coordinate of each point corresponding thereto on the images by rotational transform for the plurality of mass distribution images obtained by irradiating the ionizing beams from different directions before synthesizing the mass distribution images.

A mass distribution measuring apparatus comprising:

• an ionizing beam irradiation unit that irradiates an ionizing beam toward a sample surface on a substrate;
• and
• an ion detection unit that detects information including a mass-to-charge ratio and a detection position of ions generated by irradiating the ionizing beam,
• wherein the apparatus further comprises:
• a direction changing unit that changes a direction of irradiating the ionizing beam to the sample surface;
• an image acquiring unit that acquires a plurality of mass distribution images from each information detected by irradiation from a plurality of incident directions;
• and
• an image synthesizing unit that synthesizes the plurality of mass distribution images, and wherein,
• the image synthesizing unit aligns an absolute coordinate at each point on the sample with a coordinate of each point corresponding thereto on the images by rotational transform for the plurality of mass distribution images obtained by irradiating the ionizing beams from different directions before synthesizing the mass distribution images,
• the image synthesizing unit further compares the plurality of mass distribution images to judge a region from which no ion is detected due to a shadow or non-uniformity of the ionizing beam on one mass distribution image, and forms a judged information image that is the judged information imaged, and
• the apparatus further comprises an image output unit that simultaneously displays the synthesized image and the judged information image.

An image acquiring method of acquiring a synthesized image with a reduced influence of an irregularity on a sample surface, comprising:

• obtaining a plurality of mass distribution images by irradiating ionizing beams to the sample surface from different directions;
• transforming the plurality of mass distribution images so that an absolute coordinate at each point on the sample is aligned with a coordinate of each point corresponding thereto on the mass distribution images;
• and
• displaying the plural pieces of transformed image information in a superimposed manner.