Development of a Hybrid Atomic Force Microscopic Measurement System Combined with White Light Scanning Interferometry

Abstract

A hybrid atomic force microscopic (AFM) measurement system combined with white light scanning interferometry for micro/nanometer dimensional measurement is developed. The system is based on a high precision large-range positioning platform with nanometer accuracy on which a white light scanning interferometric module and an AFM head are built. A compact AFM head is developed using a self-sensing tuning fork probe. The head need no external optical sensors to detect the deflection of the cantilever, which saves room on the head, and it can be directly fixed under an optical microscopic interferometric system. To enhance the system’s dynamic response, the frequency modulation (FM) mode is adopted for the AFM head. The measuring data can be traceable through three laser interferometers in the system. The lateral scanning range can reach 25 mm × 25 mm by using a large-range positioning platform. A hybrid method combining AFM and white light scanning interferometry is proposed to improve the AFM measurement efficiency. In this method, the sample is measured firstly by white light scanning interferometry to get an overall coarse morphology, and then, further measured with higher resolution by AFM. Several measuring experiments on standard samples demonstrate the system’s good measurement performance and feasibility of the hybrid measurement method.

Useful surface parameters for biomaterial discrimination

“…The few and weak correlations encountered among nano and microroughness (Table ) suggest that both techniques give complementary information and thus it is of paramount concern to include two different scales. These results are in agreement with previous authors’ recommendations of using optical measuring methods such as white light interferometry to expand the AFM measuring range and to improve roughness measuring efficiency (Tyrrell et al ., ; Guo et al ., ). Therefore, in general S a ‐S ku ‐S mid at the nanoscale and S a ‐S z at the microscale are not correlated being confirmed the complementarity of both groups of parameters.…”

“…This method has been shown to be fast, non‐destructive and accurate. The combination of both techniques has been proposed to improve the measuring efficiency of AFM for the surface characterization of biomaterials (Tyrrell et al ., ; Guo et al ., ).…”

An Optical Fiber Lateral Displacement Measurement Method and Experiments Based on Reflective Grating Panel

“…Capacitive sensors could provide excellent linearity, resolution, and bandwidth in short-range applications [ 4 ]. A sensing method with scanning probe microscopy (SPM) has become an indispensible tool for topographical measurement with nano- and sub-nanometer resolution [ 5 ], but usually the single scanning distance is of the order of 150 × 150 µm, and the scanning speed is also a limitation. Eddy current sensors have a large range with linearity error of less than ±3% [ 6 , 7 ], but they are not widely used because of the temperature sensitivity.…”

A Unique Self-Sensing, Self-Actuating AFM Probe at Higher Eigenmodes

“…Quartz tuning forks are designed for high-precision frequency control and are widely used in clocks, watches, and digital circuit frequency standards. By taking advantage of their extreme stability in frequency, their high quality factor, their self-sensing and self-actuating capabilities, and the ease with which the vibration signal may be obtained with fewer components than the conventional atomic force microscopy (AFM) probes, and so on, they can be used as force sensors in AFM [ 1 , 2 , 3 , 4 ]. The tuning fork AFM probes are typically realized in two forms ( Figure 1 ).…”