Reliability investigation of the instrument transfer function calibration technique based on binary pseudo-random array standards

Yashchuk, Valeriy V.; Munechika, Keiko; Rochester, Simon; Chao, Weilun; Lacey, Ian; Piña-Hernandez, Carlos; Takacs, Peter Z.

doi:10.1117/12.2633476

Cited by 6 publications

(12 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…To characterize the microscope's systematic errors, geometrical distortion, and ITF over an increased effective dynamic range, we use specially designed test standards and artifacts (see, for example, Refs. [26][27][28][29][30][31][32][33] and references therein). For the ITF calibration of optical microscopes, binary pseudo-random array standards patterned with the uniformly redundant [9,10] and highly randomized binary [29] arrays (URA BPRAs and HR BPRAs) with fundamental (smallest) feature size of 30 -2,500 nm are now available [30,31].…”

Section: Test Standards For Characterization Of Interferometric Micro...mentioning

confidence: 99%

“…3.3, below), we use the A1 and B1 URA PBRA patterns with the elementary sizes of 2.5 µm and 1.2 µm of a 2-in diameter BPRA standard described in detail in Refs. [31,32] -Fig. 5.…”

Section: Test Standards For Characterization Of Interferometric Micro...mentioning

confidence: 99%

“…[34]). To calibrate the ITF of a microscope in higher resolution configuration, we use a high-resolution HR BPRA standard fabricated on a 1-in diameter super-polished silicon substrate [31,32]. This standard has three HR BPRA patterns with the elementary sizes of 241 nm, 161 nm, and 81 nm, respectively.…”

Section: Test Standards For Characterization Of Interferometric Micro...mentioning

confidence: 99%

See 2 more Smart Citations

Towards super-resolution interference microscopy metrology of x-ray variable-line-spacing diffraction gratings: recent developments

Rochester¹,

English

Lacey

et al. 2022

Advances in X-Ray/Euv Optics and Components XVII

View full text Add to dashboard Cite

We report on recent work towards improving interference microscopy metrology of variable-line-spacing (VLS) x-ray diffraction gratings through a combination of techniques: image reconstruction to correct for distortion and blurring, multi-image super-resolution data acquisition to increase resolution beyond the single-image limit, and image stitching to increase the measurement area. Here, we concentrate on precision characterization and correction for lens distortion (aka geometrical distortion) and provide precise measurements of the effective image pixel distribution. We present and analyze the results of geometrical distortion measurements performed with test samples, including traditional checkerboard test artifacts and binary pseudo-random array (BPRA) standards patterned with two-dimensional uniformly redundant arrays (URA). The URA BPRA standards are also useful for measurement of the instrument transfer function (ITF), a measure of the optical aberrations and limited lateral resolution of the instrument. We also outline other essential elements and the next steps of the project on development of so-called super-resolution interference microscopy, enabling more precise measurements of VLS groove density than previously possible. The global aim of this project is to integrate our metrology technique into the manufacture of high-resolution x-ray gratings.

show abstract

Section: Test Standards For Characterization Of Interferometric Micro...mentioning

confidence: 99%

“…3.3, below), we use the A1 and B1 URA PBRA patterns with the elementary sizes of 2.5 µm and 1.2 µm of a 2-in diameter BPRA standard described in detail in Refs. [31,32] -Fig. 5.…”

Section: Test Standards For Characterization Of Interferometric Micro...mentioning

confidence: 99%

Section: Test Standards For Characterization Of Interferometric Micro...mentioning

confidence: 99%

See 1 more Smart Citation

Towards super-resolution interference microscopy metrology of x-ray variable-line-spacing diffraction gratings: recent developments

Rochester¹,

English

Lacey

et al. 2022

Advances in X-Ray/Euv Optics and Components XVII

View full text Add to dashboard Cite

show abstract

“…Figure 2 shows the upgraded ALS XROL MicroMap/OptoSURF interferometric microscope now in use at ALS XROL. Here, the microscope is arranged for the instrument transfer function (ITF) measurements with a binary pseudo-random array (BPRA) standard [19][20][21][22][23][24][25] (for more details, see also Sec. 5).…”

Section: Upgrade Of the Microscope's Optical Sensormentioning

confidence: 99%

“…To determine resolution capabilities of the upgraded system, we use a highly randomized (HR) BPRA standard [23].…”

Section: Performance Of the Upgraded Microscopementioning

confidence: 99%

The ALS interferometric microscope upgraded for measurements with large x-ray optics and optical assemblies

Lacey

Anderson²,

Barnard³

et al. 2022

Advances in X-Ray/Euv Optics and Components XVII

View full text Add to dashboard Cite

We describe details of a recent deep upgrade of the MicroMap-570 interferometric microscope available at the Advanced Light Source X-Ray Optics Laboratory. The upgrade has included an improvement of the microscope optical sensor and data acquisition software, design and implementation of automated optic alignment and microscope translation systems, and development of a specialized software for data processing in the spatial frequency domain. With the upgraded microscope, we are now capable for automated (remoted) measurements with large x-ray optics and optical systems. The results of experimental evaluation of the upgraded microscope performance and calibration of its instrument transfer function are also discussed. Because the same already obsolete MicroMap-570 microscopes have been used for years at other metrology laboratories at the x-ray facilities around the globe, we believe that our experience on upgrade of the microscope describe in detail in the present paper is broadly interesting and useful.

show abstract

Calibration, modeling, parameterization, and verification of the instrument transfer function of an interferometric microscope

Takacs¹,

Rochester²,

Lacey³

et al. 2022

Interferometry XXI

View full text Add to dashboard Cite

Interferometric microscopes are used to measure surface roughness, from which the computed power spectral density function can be used to extract bandwidth-limited values of the various surface properties, such as root-mean-square (rms) height and slope errors. Measurements with a microscope equipped with different objectives that have an overlapping spatial frequency range usually give different rms results over the common frequency bandwidth. This is a result of different instrument transfer functions (ITFs) that attenuate spatial frequencies by different amounts over the overlapping range. We report on the use of binary pseudo-random array (BPRA) standards to characterize the ITF of an interferometric microscope with the various objectives. We use a simple model of a 1D binary Results show that the spectrum for an undersampled array is a cosine function, rather than a straight line, constant white noise spectrum. We have an analytical model of the ITF that includes the effects of an obscured aperture and defocus, in addition to the usual parameters of numerical aperture, wavelength, and sampling period. In addition, the model includes the effect of aliasing of spatial frequency components beyond the Nyquist back into the sub-Nyquist region. We compare the model PSD predictions to the measurements performed with different objectives. Departures of the measured PSDs from the model predictions indicate that there are higher-order ITF corrections yet to be identified and included in the model.

show abstract

Reliability investigation of the instrument transfer function calibration technique based on binary pseudo-random array standards

Cited by 6 publications

References 35 publications

Towards super-resolution interference microscopy metrology of x-ray variable-line-spacing diffraction gratings: recent developments

Towards super-resolution interference microscopy metrology of x-ray variable-line-spacing diffraction gratings: recent developments

The ALS interferometric microscope upgraded for measurements with large x-ray optics and optical assemblies

Calibration, modeling, parameterization, and verification of the instrument transfer function of an interferometric microscope

Contact Info

Product

Resources

About