Apparatus and methods for measuring surface topography are described. The analysis apparatus and methods detect light reflected from the reflective backside of a cantilever assembly including a tip, calculate a background level (BGL) value obtained from an optical scan of a reference sample using a power spectral density (PSD) value obtained from a topographical scan of a reference sample to generate a correlational coefficient between the BGL and the PSD values. The correlational coefficient between the BGL and PSD values is used to measure the BGL value of additional EUV mask blanks by a topographical scan of the EUV mask blanks using the same tip mounted to the cantilever.

Apparatus and methods for measuring surface topography are described. The analysis apparatus and methods detect light reflected from the reflective backside of a cantilever assembly including a tip, calculate a background level (BGL) value obtained from an optical scan of a reference sample using a power spectral density (PSD) value obtained from a topographical scan of a reference sample to generate a correlational coefficient between the BGL and the PSD values. The correlational coefficient between the BGL and PSD values is used to measure the BGL value of additional EUV mask blanks by a topographical scan of the EUV mask blanks using the same tip mounted to the cantilever.

Apparatus and methods for measuring surface topography are described. The analysis apparatus and methods detect light reflected from the reflective backside of a cantilever assembly including a tip, calculate a background level (BGL) value obtained from an optical scan of a reference sample using a power spectral density (PSD) value obtained from a topographical scan of a reference sample to generate a correlational coefficient between the BGL and the PSD values. The correlational coefficient between the BGL and PSD values is used to measure the BGL value of additional EUV mask blanks by a topographical scan of the EUV mask blanks using the same tip mounted to the cantilever.

Apparatus and methods for measuring surface topography are described. The analysis apparatus and methods detect light reflected from the reflective backside of a cantilever assembly including a tip, calculate a background level (BGL) value obtained from an optical scan of a reference sample using a power spectral density (PSD) value obtained from a topographical scan of a reference sample to generate a correlational coefficient between the BGL and the PSD values. The correlational coefficient between the BGL and PSD values is used to measure the BGL value of additional EUV mask blanks by a topographical scan of the EUV mask blanks using the same tip mounted to the cantilever.

A numerically controlled rotary probe switching device based on an environment-controllable atomic force microscope (AFM) includes a cavity upper cover and a probe switching structure. The cavity upper cover is provided with an irregular rectangular boss, an inner groove, a rectangular optical window structure and a sealing flange structure. The irregular rectangular boss is provided with the rectangular optical window structure; a front end of the boss is provided with the sealing flange structure; and a lower portion of the boss is provided with an inner groove for accommodating the probe switching structure and a transition groove for matching with a linear movement of a sample carrier and a rotary switching of probes. The probe switching structure is configured inside the inner groove, and the probe switching structure is provided with at least one probe assembly.

A numerically controlled rotary probe switching device based on an environment-controllable atomic force microscope (AFM) includes a cavity upper cover and a probe switching structure. The cavity upper cover is provided with an irregular rectangular boss, an inner groove, a rectangular optical window structure and a sealing flange structure. The irregular rectangular boss is provided with the rectangular optical window structure; a front end of the boss is provided with the sealing flange structure; and a lower portion of the boss is provided with an inner groove for accommodating the probe switching structure and a transition groove for matching with a linear movement of a sample carrier and a rotary switching of probes. The probe switching structure is configured inside the inner groove, and the probe switching structure is provided with at least one probe assembly.

A scattering-type scanning near-field optical microscope at cryogenic temperatures (cryo-SNOM) configured with Akiyama probes for studying low energy excitations in quantum materials present in high magnetic fields. The s-SNOM is provided with atomic force microscopy (AFM) control, which predominantly utilizes a laser-based detection scheme for determining the cantilever tapping motion of metal-coated Akiyama probes, where the cantilever tapping motion is detected through a piezoelectric signal. The Akiyama-based cryo-SNOM attains high spatial resolution, good near-field contrast, and is able to perform imaging with a significantly more compact system capable of handling simultaneous demands of vibration isolation, low base temperature, precise nano-positioning, and optical access. Results establish the potential of s-SNOM based on self-sensing piezo-probes, which can easily accommodate near-IR and far-infrared wavelengths and high magnetic fields. Using a tuning fork-based Akiyama probe provides nano-imaging capability at room and low temperatures and is used for near-field photocurrent mapping.

A scattering-type scanning near-field optical microscope at cryogenic temperatures (cryo-SNOM) configured with Akiyama probes for studying low energy excitations in quantum materials present in high magnetic fields. The s-SNOM is provided with atomic force microscopy (AFM) control, which predominantly utilizes a laser-based detection scheme for determining the cantilever tapping motion of metal-coated Akiyama probes, where the cantilever tapping motion is detected through a piezoelectric signal. The Akiyama-based cryo-SNOM attains high spatial resolution, good near-field contrast, and is able to perform imaging with a significantly more compact system capable of handling simultaneous demands of vibration isolation, low base temperature, precise nano-positioning, and optical access. Results establish the potential of s-SNOM based on self-sensing piezo-probes, which can easily accommodate near-IR and far-infrared wavelengths and high magnetic fields. Using a tuning fork-based Akiyama probe provides nano-imaging capability at room and low temperatures and is used for near-field photocurrent mapping.