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Atomic force microscopy (AFM) has been adopted in both industry and academia for high‐fidelity, full‐profile topographic characterization. Typically, the tiny tip of the cantilever and the limited traveling range of the scanner restrict AFM measurement to relatively flat samples (recommend 1 µm). The primary objective of this work is to address these limitations using a large‐range AFM (measuring height >10 µm) system consisting of a novel repairable high aspect ratio probe (HARP) with a nested‐proportional‐integral‐derivative (nested‐PID) AFM system. The HARP is fabricated using a reliable, cost‐efficient bench‐top process. The tip is then fused by pulling the end of the micropipette cantilever with a length up to hundreds of micrometers and a tip diameter of 30 nm. The design, simulation, fabrication, and performance of the HARP are described herein. This instrument is then tested using polymer trenches which reveals superior image fidelity compared to standard silicon tips. Finally, a nested‐PID system is developed and employed to facilitate 3D characterization of 50‐µm‐step samples. The results demonstrate the efficacy of the proposed bench‐top technique for the fabrication of low‐cost, simple HAR AFM probes that facilitate the imaging of samples with deep trenches. [ABSTRACT FROM AUTHOR]

Ultrahigh frequency ultrasound (>60 MHz) has emerged as a crucial actuating mechanism for non-contact manipulation, owing to its unique acoustic field properties. The acoustic field traps microparticles mainly via the gradient force of acoustic radiation force (ARF) on the transverse plane, which is up to hundreds of nanonewtons. In theory, directly using ARF can strengthen the manipulation force. Currently, the direct implementation of ARF is restricted to a specific frequency and magnitude range, which lacks a comprehensive and versatile control method. Additionally, it lacks an ARF calibration method that accommodates a wide magnitude and frequency range. We propose a variable frequency pulse width modulation-based control method for ARF, which uses an atomic force microscope microcantilever as a mechanical sensor to calibrate the magnitude and frequency. The precise control of ARF emitted by an 85 MHz transducer was achieved with a resolution of hundreds of piconewtons, magnitude range spanning from nanonewtons to micronewtons, and frequency range of 1 kHz to hundreds of kilohertz. This control method breakthrough holds great promise for expanding the application of ultrahigh frequency ultrasound in noncontact manipulation. [ABSTRACT FROM AUTHOR]

With the rapid evolution of microelectronics and nanofabrication technologies, the feature sizes of large‐scale integrated circuits continue to move toward the nanoscale. There is a strong need to improve the quality and efficiency of integrated circuit inspection, but it remains a great challenge to provide both rapid imaging and circuit node‐level high‐resolution images simultaneously using a conventional microscope. This paper proposes a nondestructive, high‐throughput, multiscale correlation imaging method that combines atomic force microscopy (AFM) with microlens‐based scanning optical microscopy. In this method, a microlens is coupled to the end of the AFM cantilever and the sample‐facing side of the microlens contains a focused ion beam deposited tip which serves as the AFM scanning probe. The introduction of a microlens improves the imaging resolution of the AFM optical system, providing a 3–4× increase in optical imaging magnification while the scanning imaging throughput is improved ≈8×. The proposed method bridges the resolution gap between traditional optical imaging and AFM, achieves cross‐scale rapid imaging with micrometer to nanometer resolution, and improves the efficiency of AFM‐based large‐scale imaging and detection. Simultaneously, nanoscale‐level correlation between the acquired optical image and structure information is enabled by the method, providing a powerful tool for semiconductor device inspection. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Developing an effective layer-controllable fabrication technique for two-dimensional materials is crucial, as numerous novel properties are closely related to the varying layers and the artificial nanostructures. To achieve this goal, a novel technique was proposed based on the model between the phase variation and the characteristic parameters of the material. Based on the theoretical estimation and fabrications related to the phase information, cutting with controllable layers and sharp edges was achieved on monolayer and multilayer MoS 2 nanosheets. Both theoretical analysis and experimental results demonstrate the feasibility of our method and suggest its potential for wide application in the future. [ABSTRACT FROM AUTHOR]

Atomic force microscopy (AFM) mechanical-based lithography attracts much attention in nanomanufacturing due to its advantages of low cost, high precision and high resolution. However, debris effects during mechanical lithography often lead to an unstable machining process and inaccurate results, which limits further applications of AFM-based lithography. There is a lack of a real-time debris detection approach, which is the prerequisite to eventually eliminating the influence of the debris, and of a method that can solve the above problems well. The ultrasonic vibration (USV)-assisted AFM has the ability to sense the machining depth in real time by detecting the phase shifting of cantilever. However, whether the pile-up of debris affect the phase response of cantilever is still lack of investigation. Therefore, we analyzed the mechanism of the debris effect on force control mode and investigated the relationship between phase shifting and pile-up of debris. Theoretical analysis and experimental results reveal that the pile-up of debris have negligible effect on phase shifting of cantilever. Therefore, the phase shifting-based method can detect the debris effect on machining depth in force control mode of AFM machining. [ABSTRACT FROM AUTHOR]

Machining or patterning ultra-thin films with specified structures are critical challenges. In this work, a novel mode of atomic force microscopy nanomachining is proposed. The phase response of the cantilever is used as the input of feedback control to modulate the machining force to achieve the desired machined depth. The proposed phase mode, overcoming the disadvantages of force mode, is not affected by the debris piled-up and has the ability to sense the interface of an ultra-thin film and predict the machining depth without post-imaging. The effectiveness of the phase mode has been proven by experiments. [ABSTRACT FROM AUTHOR]