Standard sample and method for measuring near field scanning optical microscope (NSOM) probe hole diameter

Abstract

The invention provides a standard sample for measuring near field scanning optical microscope (NSOM) probe hole diameter size, which comprises a transmitting substrate (1) and a light-proof film layer (2) on the surface of the substrate (1), wherein the film layer (2) is provided with at least one measuring unit (3); each measuring unit (3) comprises at least two rectangular film-free layer areas; the film-free layer areas are arranged in sequence along the axis direction of the measuring unit; adjacent two film-free layer areas are divided by a film line (5); and the width of the film line (5) is larger than the probe hole diameter size to be measured. The invention also provides a method for measuring NSOM probe hole diameter according to the standard sample. The standard sample and the method for measuring probe hole diameter size are suitable for various NSOMs, do not need any additional attachment equipment and are convenient for use; by adopting the firm substrate and the film layer, the invention ensures that the performance of a probe can not be influenced in measurement and the probe can be reused; and the invention has accurate a measurement result and ensures that the probe hole diameter size corresponds to an NSOM set parameter.

Description

technical field [0001] The invention relates to the field of measurement, in particular to a standard sample for measuring the aperture of a near-field scanning optical microscope probe and a measurement method thereof. Background technique [0002] Near-field scanning optical microscope (NSOM) is a scanning probe microscope developed after STM and AFM. NSOM has broken through the optical diffraction limit. The optical spatial resolution of NSOM has reached 50nm. It is an important nanoscience research. Measurement equipment (see: "Optical Instruments" Volume 22, Issue 6, 2000, article entitled "Traditional Optical Microscope and Near-field Optical Microscope"). The spatial resolution of NSOM is mainly determined by the size of the probe aperture. The image is formed by point-by-point scanning. If the scanning step is larger than the probe aperture, there will be missing optical information. If the scanning step is smaller than the probe aperture, there will be Optical info...

AI Technical Summary

Problems solved by technology

Therefore, during the measurement process, people do not know the exact size of the probe aperture, which brings difficulties to the measurement and analysis of the measurement results. For this reason, people have been trying to measure the size of the probe aperture

[0003] At present, the existing probe aperture detection methods are not practical, such as scanning electron microscope measurement, which is not only expensive but also cannot give a practical aperture size; some people use a metal film after arranging organic balls on a glass substrate, and then remove the organic balls The method of measuring the aperture with a metal circular hole is not only inaccurate, but also easily causes damage to the probe; there is also the use of microelectronic etching technology to engrave the gold film plated on the glass substrate into a pattern for measurement , because of the plasma enhancement of the gold film, reliable measurement results cannot be given; there is also the use of far-field detection to detect the spatial distribution of the near-field light intensity of the probe, and then calculate the probe aperture (US Patent: US 6791071B2), not only High-sensitivity detectors are required, and the equipment is complicated, and the results given are neither accurate nor practical; the knife-edge method is also commonly used in the measurement of the probe aperture. When the probe sweeps across the knife-edge, the rising or falling part of the measurement signal is used. The pore diameter of the probe can be determined, provided that the thickness of the knife edge is much smaller than the pore size, and the thickness of the film layer that can be used to measure the pore size of the NSOM probe is greater than 50nm, which is in the same order of magnitude as the pore size of the NSOM probe. The measured rise or The falling signal is between two planes with a difference greater than 50nm at different heights, and the measurement result will deviate from the actual probe aperture size value. Therefore, the knife-edge method is not suitable for the measurement of the NSOM probe aperture

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