提高石英表面聚焦离子束微纳直写精度的方法

针对聚焦离子束在绝缘材料表面直写微纳图形时因电荷积聚原因导致加工效果差的情况,将单晶硅湿法各向异性腐蚀工艺应用于单晶硅片表面制备倒金字塔形通孔,作为微窗硅基盖板覆盖于绝缘衬底表面。当聚焦离子束穿过通孔在非导电衬底表面进行溅射刻蚀时,微窗硅基盖板的导电特性可提高溅射出的带电粒子的迁移率,降低电荷积聚-放电的频率,从而有助于聚焦离子束在绝缘衬底表面进行微纳加工。试验在具备高分辨率扫描电子显微镜成像和聚焦离子束微纳加工功能的双束系统中进行。试验结果显示被微窗硅基盖板的通孔环绕的石英表面的刻蚀结果与未被环绕的对比,刻蚀效果有显著改善,甚至部分刻蚀结果与单晶硅表面的刻蚀结果一致。

Applications of nanostructures in wide-field, label-free super resolution microscopy

Super resolution imaging capable of resolving details beyond the diffraction limit is highly desired in many scientific and application fields, including bio-medicine, nanomaterial science, and opto-electronic integration. Up to now, many different methods have been proposed, among which wide-field, label-free super resolution microscopy is indispensable due to its good applicability to diverse sample types, large field of view（FOV）, and high imaging speed. In recent years,nanostructures have made a crucial contribution to the wide-field, label-free subdiffraction microscopy, with various working mechanisms and configuration designs. This review summarizes the recent applications of the nanostructures in the wide-field, label-free super resolution microscopy, with the emphasis on the designs of hyperlens with hyperbolic dispersion, microsphere with ＂nano-jets＂, and nanowire ring illumination microscopy based on spatial frequency shift effect. The bottlenecks of the current techniques and possible solutions are also discussed.

A modulated sparse random matrix for high-resolution and high-speed 3D compressive imaging through a multimode fiber

Multimode fiber(MMF)possesses intrinsic,ultrathin,noninvasive geometric characteristics and high mode density optical characteristics,having great potential in endoscopic imaging[1,2].A typical MMF endoscopic imaging system involves a camera placed behind the fiber distal end to calibrate the transmission matrix(TM)of the fiber,and when imaging into narrow channels,such as bronchus,or performing insertion into brain tissues,the camera should be replaced by a single-pixel detector placed outside in a reflection mode to record the signal.A traditional MMF imaging system adopts the point scan mode,whose resolution is limited by the numerical aperture(NA)of the fiber,and the imaging speed is restricted by the refresh rate of the modulator and the Nyquist sampling law.The need for high resolution,high speed,and three-dimensional(3D)imaging for observation of biological processes,such as neural activity,blood flow detection,and cellular dynamics,calls for original imaging approaches.

Spatial-frequency-shift enables integrated super-resolution microscopy:advance and perspective

The invention of the optical microscope is significant to the development of many aspects of science and technology,including novel materials,life sciences and medicine,for its superiorities in resolving fine structures.But,restrained by the Abbe diffraction limit。