Microsphere assisted microscopy (MAM) has been rapidly developed to meet the measurement needs of microstructures. MAM can be integrated with optical interference microscopy (OIM) to achieve high lateral resolution surface profile measurement. However, the microspheres introduce intricate phase changes, resulting in optical path asymmetry which is very challenging to compensate for. This limitation constrains the application of MAM in OIM. In this paper, simulation analysis reveals that the phase transmission of the microsphere is influenced by parameters such as microsphere diameter and its relative position to the sample. It is concluded that a unique compensation process must be adopted for each individual microsphere. Addressing this issue, we proposed a phase compensation algorithm based on the three-dimensional position control of the microsphere and integrated it into our combined system of MAM and white light interferometry (WLI), reducing the phase errors introduced by the microspheres while enhancing the lateral resolution of optical system. This approach improved the profile measurement accuracy, offering a perspective for optically measuring the surface profile of intricate microstructures.

Two-dimensional transition metal dichalcogenides (2D TMDs) with metal-insulator transition (MIT) have garnered significant attention for their potential in elucidating electronic state regulation mechanisms and advancing novel electronic devices, ultra-low power switches, and memory technologies. Generally, MIT behavior is often obscured by Schottky barrier (SB). Previous approaches, such as using four-probe methods or barrier-free van der Waals (vdW) semimetal electrodes, have aimed to eliminate the influence of SB on MIT. However, these methods are either complicated by intricate fabrication and testing processes or limited by the availability of suitable semimetal electrodes. Here, we demonstrated a bias voltage (V_ds)-switchable MIT in pure vdW TMDs field-effect transistors (FETs) for the first time, driven by V_ds-tunable effective SB and charge injection mechanisms. We identified a conversion voltage (V_conversion), which can be reduced by eliminating extra tunneling barriers introduced by vdW gaps before the inherent SB. This work offers comprehensive perspective on how tunneling barriers influence MIT and introduces a straightforward approach to fabricating MIT-based electronic devices.

Microsphere-assisted microscopy (MAM) is a technique aimed at enhancing the lateral resolution of optical microscopy, enabling high lateral resolution profile measurement when combined with interferometry. MAM can operate in lift mode, facilitating the selection of regions of interest and expanding the field of view. The analysis of the lifting mode of microspheres in microsphere-assisted interferometry is still insufficient, which affects the longitudinal measurement accuracy of microsphere-assisted interferometry. The phase transmission mechanism of the microsphere was simulated in this paper, and the relationship between the phase distribution below the microsphere and the distance between the microsphere and the sample was summarized. A combined system of microsphere-assisted white light interference microscope was constructed, and the magnification factor and phase distribution of the microsphere in lift mode was measured through atomic force microscope atomic force microscope (AFM) control of the microsphere’s position. The experiment validated the simulated results of microsphere phase transmission, providing a theoretical foundation for microsphere-assisted interferometry(MAI) in lift mode.

Flash memories and semiconductor p-n junctions are two elementary but incompatible building blocks of most electronic and optoelectronic devices. The pressing demand to efficiently transfer massive data between memories and logic circuits, as well as for high data storage capability and device integration density, has fueled the rapid growth of technique and material innovations. Two-dimensional (2D) materials are considered as one of the most promising candidates to solve this challenge. However, a key aspect for 2D materials to build functional devices requires effective and accurate control of the carrier polarity, concentration and spatial distribution in the atomically thin structures. Here, a non-volatile opto-electrical doping approach is demonstrated, which enables reversibly writing spatially resolved doping patterns in the MoTe₂ conductance channel through a MoTe₂/hexagonal boron nitride (h-BN) heterostructure. Based on the doping effect induced by the combination of electrostatic modulation and ultraviolet light illumination, a 3-bit flash memory and various homojunctions on the same MoTe₂/BN heterostructure are successfully developed. The flash memory achieved 8 well distinguished memory states with a maximum on/off ratio over 10⁴. Each state showed negligible decay during the retention time of 2,400 s. The heterostructure also allowed the formation of p-p, n-n, p-n, and n-p homojunctions and the free transition among these states. The MoTe₂ p-n homojunction with a rectification ratio of 10³ exhibited excellent photodetection and photovoltaic performance. Having the memory device and p-n junction built on the same structure makes it possible to bring memory and computational circuit on the same chip, one step further to realize near-memory computing.

Inefficient sample preparation methods hinder the performance of high-throughput single-molecule force spectroscopy (H-SMFS) for viscous damping among reactants and unstable linkage. Here, we demonstrated a sample preparation method for H-SMFS systems to achieve a higher ratio of effective target molecules per sample cell by gas-phase silanization and reactant hydrophobization. Digital holographic centrifugal force microscopy (DH-CFM) was used to verify its performance. The experimental result indicated that the DNA stretching success ratio was improved from 0.89% to 13.5%. This enhanced efficiency preparation method has potential application for force-based DNA stretching experiments and other modifying procedures.