Pub Date : 2024-01-05DOI: 10.20965/ijat.2024.p0066
Kento Tokuchi, Mikio Kurita, Keisuke Takahashi
Freeform surfaces can realize optical systems with a wide field of view, high throughput, and high contrast. For constructing optical systems with freeform surfaces, measuring technology is essential. However, it is difficult to measure freeform surfaces by existing measurement methods. We have developed a new measurement method of the dragging three-point method (DTPM). To realize further improvement in the accuracy of the DTPM, we propose the DTPM with a circular path. Since the circular path is closed, the measurement error can be reduced by the boundary condition that the height and slope agree with at the start and end points of the measurement. To evaluate this method, we conducted the circular path measurement of an off-axis asphere. The measurement repeatability was RMS = 1.5 nm, and the result agreed well with that of an interferometric test; the difference was RMS = 17.2 nm.
{"title":"Measurement of a Freeform Surface by Dragging Three Point Method Along with a Circular Path","authors":"Kento Tokuchi, Mikio Kurita, Keisuke Takahashi","doi":"10.20965/ijat.2024.p0066","DOIUrl":"https://doi.org/10.20965/ijat.2024.p0066","url":null,"abstract":"Freeform surfaces can realize optical systems with a wide field of view, high throughput, and high contrast. For constructing optical systems with freeform surfaces, measuring technology is essential. However, it is difficult to measure freeform surfaces by existing measurement methods. We have developed a new measurement method of the dragging three-point method (DTPM). To realize further improvement in the accuracy of the DTPM, we propose the DTPM with a circular path. Since the circular path is closed, the measurement error can be reduced by the boundary condition that the height and slope agree with at the start and end points of the measurement. To evaluate this method, we conducted the circular path measurement of an off-axis asphere. The measurement repeatability was RMS = 1.5 nm, and the result agreed well with that of an interferometric test; the difference was RMS = 17.2 nm.","PeriodicalId":43716,"journal":{"name":"International Journal of Automation Technology","volume":"83 8","pages":""},"PeriodicalIF":1.1,"publicationDate":"2024-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139381482","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In fabrication of a thin and large optical element, grinding with the conventional fixture cannot achieve high precision. When such a thin and large workpiece is tightly fixed to the grinder table, the inconsistency in the form of the contact surfaces and thermal expansion of them produce unexpected stress on the workpiece. After finishing grinding with the fixture, the deformation of the ground surface would happen, accompanied by the release of the stress. This paper proposes a stress-free fixture method by removing over-constraint from the fixture structure. Corrective grinding is executed by calculating the deformation of the workpiece due to the load of the grinding wheel. Furthermore, the fixture enables on-machine measurement by an interferometer above the grinder by replicating the same condition as when the optical element is in use. We achieved a precision of RMS 0.30 µm on a one-meter-size glass ceramic of 60 mm in thickness.
{"title":"High-Precision Grinding of Thin and Large Optical Workpieces with the Kinematic Support","authors":"Takeshi Hashigaya, Masaru Kino, Keisuke Takahashi, Mikio Kurita","doi":"10.20965/ijat.2024.p0039","DOIUrl":"https://doi.org/10.20965/ijat.2024.p0039","url":null,"abstract":"In fabrication of a thin and large optical element, grinding with the conventional fixture cannot achieve high precision. When such a thin and large workpiece is tightly fixed to the grinder table, the inconsistency in the form of the contact surfaces and thermal expansion of them produce unexpected stress on the workpiece. After finishing grinding with the fixture, the deformation of the ground surface would happen, accompanied by the release of the stress. This paper proposes a stress-free fixture method by removing over-constraint from the fixture structure. Corrective grinding is executed by calculating the deformation of the workpiece due to the load of the grinding wheel. Furthermore, the fixture enables on-machine measurement by an interferometer above the grinder by replicating the same condition as when the optical element is in use. We achieved a precision of RMS 0.30 µm on a one-meter-size glass ceramic of 60 mm in thickness.","PeriodicalId":43716,"journal":{"name":"International Journal of Automation Technology","volume":"114 22","pages":""},"PeriodicalIF":1.1,"publicationDate":"2024-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139383391","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-05DOI: 10.20965/ijat.2024.p0026
Junichi Kouguchi, Shingo Tajima, Hayato Yoshioka
Recently, there has been an increased demand for precise monitoring of the milling process using machine tools through a simple and cost-effective method. Accurate estimation of cutting forces is highly effective for this monitoring, and one approach is the modeling of tool spindles and tables of a machine tool. To model machine structures, well-known methods involving the use of impulse hammer response or structural analysis exist. However, the complex modeling is hard to achieve when using the impulse response. Moreover, it is often considerably difficult to achieve the modeling with structural analysis because the preparation of the accurate model and highly complicated calculations are required. Therefore, in this study, we propose a new monitoring method to identify model parameters of the machine structure and estimate cutting forces. First, a simplified assumed structure is prepared based on locations where sensors can be mounted. Next, measurement data during actual milling process are collected through the acceleration sensors mounted on the tool spindle and the dynamometer for the cutting force attached to the table. Subsequently, model parameters are identified from these data using machine learning. A 3-axis NC milling machine was used to evaluate the application range of the model parameters by changing cutting conditions, milling direction, cutting tools, and materials. The model parameters identified using the proposed method were equivalent to those using the impulse response. Furthermore, even in cases where the impulse response was difficult to identify, suitable model parameters were identified using machine learning. Finally, we confirmed that the proposed method can accurately achieve in-process monitoring of cutting forces in the X, Y, and Z directions.
最近,人们越来越需要通过一种简单、经济的方法来精确监控机床的铣削过程。对切削力的精确估算对这种监控非常有效,其中一种方法是对机床的刀具主轴和工作台进行建模。在机床结构建模方面,众所周知的方法包括使用脉冲锤响应或结构分析。然而,使用脉冲响应很难实现复杂的建模。此外,由于需要准备精确的模型和进行非常复杂的计算,使用结构分析建模往往相当困难。因此,在本研究中,我们提出了一种新的监测方法来确定机床结构的模型参数并估算切削力。首先,根据可安装传感器的位置准备一个简化的假定结构。然后,通过安装在刀具主轴上的加速度传感器和安装在工作台上的切削力测力计,收集实际铣削过程中的测量数据。随后,利用机器学习从这些数据中确定模型参数。使用一台三轴数控铣床,通过改变切削条件、铣削方向、切削刀具和材料来评估模型参数的应用范围。使用建议方法确定的模型参数与使用脉冲响应确定的参数相当。此外,即使在脉冲响应难以确定的情况下,也能通过机器学习确定合适的模型参数。最后,我们证实所提出的方法可以准确地实现对 X、Y 和 Z 方向切削力的过程监控。
{"title":"Machine-Learning-Based Model Parameter Identification for Cutting Force Estimation","authors":"Junichi Kouguchi, Shingo Tajima, Hayato Yoshioka","doi":"10.20965/ijat.2024.p0026","DOIUrl":"https://doi.org/10.20965/ijat.2024.p0026","url":null,"abstract":"Recently, there has been an increased demand for precise monitoring of the milling process using machine tools through a simple and cost-effective method. Accurate estimation of cutting forces is highly effective for this monitoring, and one approach is the modeling of tool spindles and tables of a machine tool. To model machine structures, well-known methods involving the use of impulse hammer response or structural analysis exist. However, the complex modeling is hard to achieve when using the impulse response. Moreover, it is often considerably difficult to achieve the modeling with structural analysis because the preparation of the accurate model and highly complicated calculations are required. Therefore, in this study, we propose a new monitoring method to identify model parameters of the machine structure and estimate cutting forces. First, a simplified assumed structure is prepared based on locations where sensors can be mounted. Next, measurement data during actual milling process are collected through the acceleration sensors mounted on the tool spindle and the dynamometer for the cutting force attached to the table. Subsequently, model parameters are identified from these data using machine learning. A 3-axis NC milling machine was used to evaluate the application range of the model parameters by changing cutting conditions, milling direction, cutting tools, and materials. The model parameters identified using the proposed method were equivalent to those using the impulse response. Furthermore, even in cases where the impulse response was difficult to identify, suitable model parameters were identified using machine learning. Finally, we confirmed that the proposed method can accurately achieve in-process monitoring of cutting forces in the X, Y, and Z directions.","PeriodicalId":43716,"journal":{"name":"International Journal of Automation Technology","volume":"2 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2024-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139383147","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-05DOI: 10.20965/ijat.2024.p0004
Jiucheng Wu, Yifang Hong, Dong Wook Shin, R. Sato, Lue Quan, H. Matsukuma, Wei Gao
A differential angle sensor is newly developed to calibrate the pitch deviations of a linear scale grating with a nominal pitch of 1.6 µm on an ultra-precision lathe. The angle sensor is composed of two angle detection units based on the laser autocollimation method. A collimated laser beam with a diameter of 1 mm, which is output from a laser diode with a wavelength of 685 nm, is projected onto the linear scale grating. The positive and the negative first-order diffracted beams from the scale are received by the two angle detection units, respectively. The X-slide of the ultra-precision lathe is employed to generate the necessary scanning motion for the calibration. Based on the fact that the pitch deviations will cause changes in the positive and the negative first-order diffraction angles, which are equal in magnitude and opposite in sign, the pitch deviations can be obtained from the differential output of the angle sensor. The tilt error motion of the X-slide, which is a major error factor in on-machine calibration, can also be removed in the differential output. The robustness of the developed angle sensor for on-machine calibration has been confirmed by testing the basic performances of the sensor on the machine tool. The feasibility of the on-machine calibration result of pitch deviations has been verified through comparing with the off-machine calibration result.
{"title":"On-Machine Calibration of Pitch Deviations of a Linear Scale Grating by Using a Differential Angle Sensor","authors":"Jiucheng Wu, Yifang Hong, Dong Wook Shin, R. Sato, Lue Quan, H. Matsukuma, Wei Gao","doi":"10.20965/ijat.2024.p0004","DOIUrl":"https://doi.org/10.20965/ijat.2024.p0004","url":null,"abstract":"A differential angle sensor is newly developed to calibrate the pitch deviations of a linear scale grating with a nominal pitch of 1.6 µm on an ultra-precision lathe. The angle sensor is composed of two angle detection units based on the laser autocollimation method. A collimated laser beam with a diameter of 1 mm, which is output from a laser diode with a wavelength of 685 nm, is projected onto the linear scale grating. The positive and the negative first-order diffracted beams from the scale are received by the two angle detection units, respectively. The X-slide of the ultra-precision lathe is employed to generate the necessary scanning motion for the calibration. Based on the fact that the pitch deviations will cause changes in the positive and the negative first-order diffraction angles, which are equal in magnitude and opposite in sign, the pitch deviations can be obtained from the differential output of the angle sensor. The tilt error motion of the X-slide, which is a major error factor in on-machine calibration, can also be removed in the differential output. The robustness of the developed angle sensor for on-machine calibration has been confirmed by testing the basic performances of the sensor on the machine tool. The feasibility of the on-machine calibration result of pitch deviations has been verified through comparing with the off-machine calibration result.","PeriodicalId":43716,"journal":{"name":"International Journal of Automation Technology","volume":"38 4","pages":""},"PeriodicalIF":1.1,"publicationDate":"2024-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139382336","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-05DOI: 10.20965/ijat.2024.p0003
Yasuhiro Takaya, Wei Gao
The Internet of Things is playing an important role, organizing all things that use data and connecting them to the Internet. It has been made possible by the rapid progress in smart and real-time measurement technologies, the miniaturization and speeding up of sensor technologies as well as intelligent data processors, and by the spread of cloud technology, which accumulates huge amounts of data. To establish smart and precision manufacturing, not only the improvement of conventional ultraprecision machining techniques but also the development of the novel, high-performance machining techniques has been made. On-machine and in-process measurement are gaining in importance for emerging machining technologies as well as conventional ones. Advanced techniques of machining and metrology as well as feedback for compensation manufacturing have been required for plasticity to on-machine and in-process conditions. This special issue focuses on metrology and manufacturing measurement and instrumentation for the progress of state-of-the-art on-machine and in-process measurement systems and sensor technologies. It consists of contributions related to, but not limited to, the following topics: - On-machine, in-process measurement and process monitoring - Practical application of on-machine, in-process measurement - Machine tool metrology - Intelligent micro- and nano-metrology - Multi-sensor fusion and multi-sensor cooperation - Form and dimensional measurement and instrumentation - 3D-surface texture and its micro-characteristics - Machine learning, AI aided measurement We would like to sincerely thank all the authors for their contributions, and we sincerely hope that the papers in this special issue further contribute to the development of our future society from a new horizon of metrology.
{"title":"Special Issue on On-Machine and In-Process Measurement for Smart and Precision Manufacturing","authors":"Yasuhiro Takaya, Wei Gao","doi":"10.20965/ijat.2024.p0003","DOIUrl":"https://doi.org/10.20965/ijat.2024.p0003","url":null,"abstract":"The Internet of Things is playing an important role, organizing all things that use data and connecting them to the Internet. It has been made possible by the rapid progress in smart and real-time measurement technologies, the miniaturization and speeding up of sensor technologies as well as intelligent data processors, and by the spread of cloud technology, which accumulates huge amounts of data. To establish smart and precision manufacturing, not only the improvement of conventional ultraprecision machining techniques but also the development of the novel, high-performance machining techniques has been made. On-machine and in-process measurement are gaining in importance for emerging machining technologies as well as conventional ones. Advanced techniques of machining and metrology as well as feedback for compensation manufacturing have been required for plasticity to on-machine and in-process conditions.\u0000 This special issue focuses on metrology and manufacturing measurement and instrumentation for the progress of state-of-the-art on-machine and in-process measurement systems and sensor technologies. It consists of contributions related to, but not limited to, the following topics:\u0000 - On-machine, in-process measurement and process monitoring\u0000 - Practical application of on-machine, in-process measurement\u0000 - Machine tool metrology\u0000 - Intelligent micro- and nano-metrology\u0000 - Multi-sensor fusion and multi-sensor cooperation\u0000 - Form and dimensional measurement and instrumentation\u0000 - 3D-surface texture and its micro-characteristics\u0000 - Machine learning, AI aided measurement\u0000 We would like to sincerely thank all the authors for their contributions, and we sincerely hope that the papers in this special issue further contribute to the development of our future society from a new horizon of metrology.","PeriodicalId":43716,"journal":{"name":"International Journal of Automation Technology","volume":"117 18","pages":""},"PeriodicalIF":1.1,"publicationDate":"2024-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139383301","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-05DOI: 10.20965/ijat.2024.p0018
Nozomu Takahiro, Yuki Shimizu
A technique to realize in-situ evaluation of the pitch of interference fringe patterns in a non-orthogonal Lloyd’s mirror interferometer is proposed. The proposed method employs two laser sources with different wavelengths. Two magnified collimated laser beams with different wavelengths are then projected onto a non-orthogonal Lloyd’s mirror interferometer to generate interference fringe patterns with different pitches. The interference fringe patterns with a pitch g1 generated by a laser beam with a wavelength λ1 sensitive to the photoresist layer are employed for the pattern exposure, while the ones generated by a laser beam with a wavelength λ2 insensitive to the photoresist layer are employed to be observed by a microscopic optical system located at the back of the exposure substrate. This enables the estimation of the pitch of the interference fringe patterns with the pitch g1 during the exposure process in optical interference lithography, contributing to accelerating the alignment of the angular position of the reflective mirror in the interferometer. A prototype optical setup consisting of a beam-collimating unit with two laser sources having wavelengths of 405 nm and 780 nm, a non-orthogonal one-axis Lloyd’s mirror interferometer unit, and a microscopic optical system is designed and developed, and experiments are conducted to demonstrate the feasibility of the proposed technique of estimating the pitch of interference fringe patterns for pattern exposure.
{"title":"A Technique for Estimating the Pitch of Interference Fringe Patterns for Pattern Exposure in a Non-Orthogonal One-Axis Lloyd’s Mirror Interferometer","authors":"Nozomu Takahiro, Yuki Shimizu","doi":"10.20965/ijat.2024.p0018","DOIUrl":"https://doi.org/10.20965/ijat.2024.p0018","url":null,"abstract":"A technique to realize in-situ evaluation of the pitch of interference fringe patterns in a non-orthogonal Lloyd’s mirror interferometer is proposed. The proposed method employs two laser sources with different wavelengths. Two magnified collimated laser beams with different wavelengths are then projected onto a non-orthogonal Lloyd’s mirror interferometer to generate interference fringe patterns with different pitches. The interference fringe patterns with a pitch g1 generated by a laser beam with a wavelength λ1 sensitive to the photoresist layer are employed for the pattern exposure, while the ones generated by a laser beam with a wavelength λ2 insensitive to the photoresist layer are employed to be observed by a microscopic optical system located at the back of the exposure substrate. This enables the estimation of the pitch of the interference fringe patterns with the pitch g1 during the exposure process in optical interference lithography, contributing to accelerating the alignment of the angular position of the reflective mirror in the interferometer. A prototype optical setup consisting of a beam-collimating unit with two laser sources having wavelengths of 405 nm and 780 nm, a non-orthogonal one-axis Lloyd’s mirror interferometer unit, and a microscopic optical system is designed and developed, and experiments are conducted to demonstrate the feasibility of the proposed technique of estimating the pitch of interference fringe patterns for pattern exposure.","PeriodicalId":43716,"journal":{"name":"International Journal of Automation Technology","volume":"117 16","pages":""},"PeriodicalIF":1.1,"publicationDate":"2024-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139383302","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-05DOI: 10.20965/ijat.2024.p0058
T. Uenohara, Makoto Yasuda, Yasuhiro Mizutani, Yasuhiro Takaya
Three-dimensional micro- and submicrometer-scale structures exhibit unique functions that cannot be obtained with bulk materials. To create such three-dimensional microstructures with high precision and efficiency, we proposed laser ablation using a photonic nanojet. A photonic nanojet is an optical beam with both a small beam diameter and a large depth of focus, which is obtained by irradiating a dielectric microsphere using a laser beam. In this study, we proposed an in-process depth measurement method to improve the machining accuracy of laser ablation using a photonic nanojet. We focused on the propagation characteristics of the shock waves generated during laser ablation. Shock waves were generated at the deepest point of the machining area and reached the microspheres as the pressure decayed, showing that different machining depths exerted different pressures on the microspheres. The microspheres were displaced by the pressure of the shock wave, and the amount of displacement depended on the pressure. Therefore, microspheres can be used as probes for shock wave detection, and the machining depth can be determined by measuring the displacement of microspheres during photonic nanojet machining. In this study, the displacement of a microsphere was measured simultaneously during photonic nanojet machining using a confocal optical system. From the obtained microsphere vibration data, the effect of the shock wave pressure was extracted, and the displacement of the microsphere due to the shock wave was obtained. When the hole depth varied from 155 to 1121 nm, the displacement of the microspheres varied from 0.58 to 0.03 µm. The experimental results show that the displacement of the microspheres vibrated by the shock wave decreased as the machining depth increased. This was due to an increase in the shock wave propagation distance and a decrease in the pressure of the shock wave as the machining depth increased. In conclusion, in-process depth measurements are possible in laser ablation using a photonic nanojet with a microsphere as a probe to detect shock waves.
{"title":"Shock Wave Detection for In-Process Depth Measurement in Laser Ablation Using a Photonic Nanojet","authors":"T. Uenohara, Makoto Yasuda, Yasuhiro Mizutani, Yasuhiro Takaya","doi":"10.20965/ijat.2024.p0058","DOIUrl":"https://doi.org/10.20965/ijat.2024.p0058","url":null,"abstract":"Three-dimensional micro- and submicrometer-scale structures exhibit unique functions that cannot be obtained with bulk materials. To create such three-dimensional microstructures with high precision and efficiency, we proposed laser ablation using a photonic nanojet. A photonic nanojet is an optical beam with both a small beam diameter and a large depth of focus, which is obtained by irradiating a dielectric microsphere using a laser beam. In this study, we proposed an in-process depth measurement method to improve the machining accuracy of laser ablation using a photonic nanojet. We focused on the propagation characteristics of the shock waves generated during laser ablation. Shock waves were generated at the deepest point of the machining area and reached the microspheres as the pressure decayed, showing that different machining depths exerted different pressures on the microspheres. The microspheres were displaced by the pressure of the shock wave, and the amount of displacement depended on the pressure. Therefore, microspheres can be used as probes for shock wave detection, and the machining depth can be determined by measuring the displacement of microspheres during photonic nanojet machining. In this study, the displacement of a microsphere was measured simultaneously during photonic nanojet machining using a confocal optical system. From the obtained microsphere vibration data, the effect of the shock wave pressure was extracted, and the displacement of the microsphere due to the shock wave was obtained. When the hole depth varied from 155 to 1121 nm, the displacement of the microspheres varied from 0.58 to 0.03 µm. The experimental results show that the displacement of the microspheres vibrated by the shock wave decreased as the machining depth increased. This was due to an increase in the shock wave propagation distance and a decrease in the pressure of the shock wave as the machining depth increased. In conclusion, in-process depth measurements are possible in laser ablation using a photonic nanojet with a microsphere as a probe to detect shock waves.","PeriodicalId":43716,"journal":{"name":"International Journal of Automation Technology","volume":"11 12","pages":""},"PeriodicalIF":1.1,"publicationDate":"2024-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139381017","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-05DOI: 10.20965/ijat.2024.p0011
M. Michihata, S. Kadoya, Satoru Takahashi
This paper describes a diameter measurement method for micro-spheres via coherent scanning interferometry (CSI) with a gauge block as the reference. The CSI system measures the height difference between the sphere and gauge block surface from both the front and back sides; then, the diameter is calculated from the measured heights via CSI and the gauge block length. For the glass sphere measured in this study, the diameter was found to be 270.556 µm with an uncertainty of 0.16 µm (k=2). Interestingly, by selecting a gauge block that matches the sphere diameter, the measurement uncertainty remained virtually unchanged, even for different sphere diameters; the proposed method achieved a relative uncertainty of 10-3–10-4. By utilizing the calibrated reference and the highly sensitive CSI system, and based on the comparator principle, the proposed method enables accurate diameter measurement without requiring specific measurement instruments.
{"title":"Diameter Measurement for Micro-Spheres via Coherent Scanning Interferometry with Reference to Gauge Block","authors":"M. Michihata, S. Kadoya, Satoru Takahashi","doi":"10.20965/ijat.2024.p0011","DOIUrl":"https://doi.org/10.20965/ijat.2024.p0011","url":null,"abstract":"This paper describes a diameter measurement method for micro-spheres via coherent scanning interferometry (CSI) with a gauge block as the reference. The CSI system measures the height difference between the sphere and gauge block surface from both the front and back sides; then, the diameter is calculated from the measured heights via CSI and the gauge block length. For the glass sphere measured in this study, the diameter was found to be 270.556 µm with an uncertainty of 0.16 µm (k=2). Interestingly, by selecting a gauge block that matches the sphere diameter, the measurement uncertainty remained virtually unchanged, even for different sphere diameters; the proposed method achieved a relative uncertainty of 10-3–10-4. By utilizing the calibrated reference and the highly sensitive CSI system, and based on the comparator principle, the proposed method enables accurate diameter measurement without requiring specific measurement instruments.","PeriodicalId":43716,"journal":{"name":"International Journal of Automation Technology","volume":"67 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2024-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139381536","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-05DOI: 10.20965/ijat.2024.p0047
Thitipat Permpatdechakul, P. Khajornrungruang, Keisuke Suzuki, A. Blattler, J. Inthiam
The experimentally observing optical systems for on-machine measurement have been developed to study on nano-polishing phenomena during the chemical mechanical polishing process, which is a wet process in semiconductor manufacturing. The developed optical system employs an evanescent field to selectively enhance exclusively the observatory of phenomena occurring on the surface being polished, offering a lateral resolving power of approximately 400 nm, in the slurry concentration of up to 5 wt% based on the numerical aperture of the objective lens. In addition, there is also the observability of 105 nm and down to 55 nm-sized silica particles without requiring additive fluorescence agents in or around the nano-particles, even when these particles are moving on surfaces such as silica glass or hard materials (silicon carbide: 4H-SiC). Consequently, the motion behavior of nano-particles disjoining with polishing pad asperity was explored and discussed, in this paper. Experimental results revealed that the polishing pad spatially constrains the movement of particles between the pad and the substrate surface, guiding them toward the surface being polished. During pad sliding, fluidically dragged nano-particles exhibit slower movement than the polishing pad sliding speed while retaining the Brownian motion. Furthermore, 105 nm-sized silica particles did not continuously approach to attach onto the SiC surface; the nano-particles approached in steps with reduced Brownian motion in all directions before attaching. This behavior can be attributed to the effects of van der Waals attraction and electrostatic repulsion forces between the particle and the substrate surfaces.
{"title":"Experimental In-Situ Observatory on Brownian Motion Behavior of 105 nm Sized Silica Particles During Chemical Mechanical Polishing of 4H-SiC by an Evanescent Field","authors":"Thitipat Permpatdechakul, P. Khajornrungruang, Keisuke Suzuki, A. Blattler, J. Inthiam","doi":"10.20965/ijat.2024.p0047","DOIUrl":"https://doi.org/10.20965/ijat.2024.p0047","url":null,"abstract":"The experimentally observing optical systems for on-machine measurement have been developed to study on nano-polishing phenomena during the chemical mechanical polishing process, which is a wet process in semiconductor manufacturing. The developed optical system employs an evanescent field to selectively enhance exclusively the observatory of phenomena occurring on the surface being polished, offering a lateral resolving power of approximately 400 nm, in the slurry concentration of up to 5 wt% based on the numerical aperture of the objective lens. In addition, there is also the observability of 105 nm and down to 55 nm-sized silica particles without requiring additive fluorescence agents in or around the nano-particles, even when these particles are moving on surfaces such as silica glass or hard materials (silicon carbide: 4H-SiC). Consequently, the motion behavior of nano-particles disjoining with polishing pad asperity was explored and discussed, in this paper. Experimental results revealed that the polishing pad spatially constrains the movement of particles between the pad and the substrate surface, guiding them toward the surface being polished. During pad sliding, fluidically dragged nano-particles exhibit slower movement than the polishing pad sliding speed while retaining the Brownian motion. Furthermore, 105 nm-sized silica particles did not continuously approach to attach onto the SiC surface; the nano-particles approached in steps with reduced Brownian motion in all directions before attaching. This behavior can be attributed to the effects of van der Waals attraction and electrostatic repulsion forces between the particle and the substrate surfaces.","PeriodicalId":43716,"journal":{"name":"International Journal of Automation Technology","volume":"102 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2024-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139383591","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-05DOI: 10.20965/ijat.2024.p0092
Satoshi Itakura, T. Uenohara, Yasuhiro Mizutani, Yasuhiro Takaya
We are currently developing a high-precision and wide-range in-process surface topography measurement system using the laser inverse scattering method. In the laser inverse scattering method, a monochromatic plane wave is illuminated perpendicular to the target surface and the surface topography is measured by retrieving the phase distribution of the reflected light. However, the dynamic range of this method is limited to the sub-micrometer range because of phase wrapping during phase retrieval. In this paper, we propose a laser inverse scattering method using a multi-wavelength light source based on the fact that the phase of light is inversely proportional to the wavelength with the propagation distance as a coefficient. We also constructed a surface profilometer based on the proposed method and measured the profile of a single rectangular groove with a width of 50 µm and a depth of 2 µm. The dimensions of the measured profiles agree well with the nominal dimensions of the rectangular groove.
{"title":"Phase Retrieval Algorithm for Surface Topography Measurement Using Multi-Wavelength Scattering Spectroscopy","authors":"Satoshi Itakura, T. Uenohara, Yasuhiro Mizutani, Yasuhiro Takaya","doi":"10.20965/ijat.2024.p0092","DOIUrl":"https://doi.org/10.20965/ijat.2024.p0092","url":null,"abstract":"We are currently developing a high-precision and wide-range in-process surface topography measurement system using the laser inverse scattering method. In the laser inverse scattering method, a monochromatic plane wave is illuminated perpendicular to the target surface and the surface topography is measured by retrieving the phase distribution of the reflected light. However, the dynamic range of this method is limited to the sub-micrometer range because of phase wrapping during phase retrieval. In this paper, we propose a laser inverse scattering method using a multi-wavelength light source based on the fact that the phase of light is inversely proportional to the wavelength with the propagation distance as a coefficient. We also constructed a surface profilometer based on the proposed method and measured the profile of a single rectangular groove with a width of 50 µm and a depth of 2 µm. The dimensions of the measured profiles agree well with the nominal dimensions of the rectangular groove.","PeriodicalId":43716,"journal":{"name":"International Journal of Automation Technology","volume":"19 9","pages":""},"PeriodicalIF":1.1,"publicationDate":"2024-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139383420","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}