Electron beam exposure or system inspection or measurement apparatus and its method and height detection apparatus

A method of obtaining an image of a specimen, comprising the steps of:

• irradiating an electron beam onto a specimen set on a table;
• optically detecting height of a surface of the specimen set on the table by projecting light onto the surface of the specimen from an oblique direction to the surface and detecting light reflected from the specimen;
• focusing the electron beam onto the surface of the specimen by controlling a position of the table in a height direction in accordance with the optically detected height information;
• obtaining an image of the surface of the specimen by detecting a secondary electron emanated from the surface by the irradiation of the electron beam focused on the surface;
• and
• outputting information of a secondary electron image of the surface of the specimen obtained by the obtaining step.

A method of obtaining an image of a specimen, comprising the steps of:

• setting a specimen on a table;
• irradiating an electron beam on a specimen set on the table;
• optically detecting a height of a surface of the specimen set on the table which moves in a predetermined direction by projecting light onto the surface of the specimen from an oblique direction to the surface and detecting light reflected from the specimen;
• focusing the electron beam onto the surface of the specimen by controlling a position of the table in a height direction in accordance with information of the optically detected height;
• obtaining an image of the surface of the specimen by detecting a secondary electron emanated from the surface by the irradiation of the electron beam focused on the surface;
• and
• processing the obtained image and outputting the processed image.

A method of obtaining an image of a specimen, comprising the steps of:

• irradiating an electron beam on a specimen set on a table;
• optically detecting a height of a surface of a specimen set on the table;
• focusing the electron beam onto the surface of the specimen by controlling a relative position of a height direction between a focus position of an electron optical system from which the electron beam is irradiated and the table in accordance with information of the optically detected height;
• obtaining an image of the surface of the specimen by detecting a secondary electron emanated from the surface of the specimen by the irradiation of the electron beam focused on the surface;
• processing the obtained image;
• and
• displaying a processed information on a monitor screen.

A method of inspecting a specimen, comprising the steps of:

• irradiating an electron beam on a specimen set on a table;
• optically detecting height of a surface of a specimen set on the table;
• focusing the electron beam onto the surface of the specimen by controlling a relative position of a height direction between a focus position of an electron optical system from which the electron beam is irradiated and the table in accordance with information of the optically detected height;
• obtaining an image of the surface of the specimen by detecting a secondary electron emanated from the surface of the specimen by the irradiation of the electron beam focused on the surface;
• processing the obtained image to detect a defect of the specimen;
• and
• outputting information of the detected defect on a monitor screen.