Calibration standard member, method for manufacturing the member and scanning electronic microscope using the member

A method for fabricating a standard member for calibration a scanning electronic microscope, wherein, from information for intensity of secondary or reflected electrons generated by scanning an observation region of a specimen to be measured by an incident electron beam, the scanning electronic microscope performs measurement of a pattern within the observation region, and

• wherein the standard member for calibration comprising a calibration pattern area on a cross-section surface of a bonded substrate and the calibration pattern area comprising a pair of concavity and convexity patterns,
• the method comprising steps of:
• forming a first substrate having a multi-layer film structure over a substrate whose surface comprises a (110) surface or a (100) surface by depositing different materials in layers periodically at a constant pitch between layers over the substrate surface;
• forming a second substrate having a multi-layer film structure not including layers formed at the same pitch linewidth as in the multi-layer film structure of the first substrate over a substrate whose surface comprises a (110) surface or a (100) surface;
• bonding the first and second substrates together such that the surfaces of both multi-layer film structures join together, thus forming a bonded substrate;
• making a sample cube with cross-section sides of the bonded substrate being exposed;
• and
• selectively etching one of the materials of the layers deposited periodically in the multi-layer film structure in one of the cross-section sides and making a bonded cross-section sample having a constant pitch concavity and convexity pattern,
• wherein, in the step of making the sample cube, the cross-section surfaces are (111) surfaces when the surface of the each substrate is a (110) surface and the cross-section surfaces are (110) surfaces when the surface of the each substrate is a (100) surface.

A scanning electronic microscope that, from information for intensity of secondary or reflected electrons generated by scanning an observation region of a specimen to be measured by an incident electron beam, performs measurement of a pattern within the observation region, the scanning electronic microscope comprising:

• a specimen stage that supports the specimen or a standard member for calibration;
• an irradiation optical system that scans the specimen on the specimen stage by an electron beam;
• a detector that detects secondary or reflected electrons generated by scanning by the electron beam;
• a signal processing means that makes a length measurement of the specimen by processing electronic signals obtained from the detector;
• a display means on which length measurement results are displayed;
• a bias power supply that applies a voltage to the specimen stage to control a voltage accelerating the electron beam;
• and a calibration function that performs magnification calibration of the irradiation optical system from information for intensity of the secondary or reflected electrons with respect to the standard member for calibration mounted on the specimen stage,
• wherein the standard member for calibration comprises:
• a bonded substrate into which a first sample cube and a second sample cube, each comprising a multi-layer film structure in which different materials are alternately deposited in layers over the surface of a substrate and its cross-section surfaces, are bonded together, their plane directions being aligned in the same orientation at the surfaces of both the multi-layer film structures;
• and
• a calibration pattern area defined on one of the cross-section surfaces of the bonded substrate,
• wherein a pair of concavity and convexity patterns are formed in the calibration pattern area by fabricating the each multi-layer film structure, the cross-section surfaces are (111) surfaces when the surfaces of the both substrates are (110) surfaces, and the cross-section surfaces are (110) surfaces when the surfaces of the both substrates are (100) surfaces.