50nm及50nm以下同步辐射X射线光刻光束线设计

X射线光刻相对于其他下一代光刻技术而言有许多优点,比如其工艺宽容度大、成品率高、景深大、曝光视场大、成本低等,更为重要的是,其技术已经比较成熟。对于100nm同步辐射X线光刻系统而言,它采用的波长通常为0．7-1．0nm,而当光刻分辨率达到50nm以下时,采用的同步辐射X射线波长范围应该为0．2—0．4nm。探讨了在北京同步辐射3B1A光刻束线上进行50nmX射线光刻的可能性。     

聚焦离子束曝光技术

聚焦离子束技术是一种集形貌观测、定位制样、成份分析、薄膜淀积和无掩模刻蚀各过程 于一身的新型微纳加工技术。它大大提高了微电子工业上材料、工艺、器件分析及修补的精度和速 度,目前已经成为微电子技术领域必不可少的关键技术之一。对聚焦离子束曝光技术作了介绍。     

Transistors Formed from a Single Lithography Step Using Information Encoded in Topography

This paper describes a strategy for the fabrication of functional electronic components (transistors, capacitors, resistors, conductors, and logic gates but not, at present, inductors) that combines a single layer of lithography with angle‐dependent physical vapor deposition; this approach is named topographically encoded microlithography (abbreviated as TEMIL). This strategy extends the simple concept of ‘shadow evaporation’ to reduce the number and complexity of the steps required to produce isolated devices and arrays of devices, and eliminates the need for registration (the sequential stacking of patterns with correct alignment) entirely. The defining advantage of this strategy is that it extracts information from the 3D topography of features in photoresist, and combines this information with the 3D information from the angle‐dependent deposition (the angle and orientation used for deposition from a collimated source of material), to create ‘shadowed’ and ‘illuminated’ regions on the underlying substrate. It also takes advantage of the ability of replica molding techniques to produce 3D topography in polymeric resists. A single layer of patterned resist can thus direct the fabrication of a nearly unlimited number of possible shapes, composed of layers of any materials that can be deposited by vapor deposition. The sequential deposition of various shapes (by changing orientation and material source) makes it possible to fabricate complex structures—including interconnected transistors—using a single layer of topography. The complexity of structures that can be fabricated using simple lithographic features distinguishes this procedure from other techniques based on shadow evaporation.     

Symmetric metamaterials based on flower-shaped structure

We proposed new models of metamaterials (MMs) based on a flower-shaped structure (FSS), whose “meta-atoms” consist of two flower-shaped metallic parts separated by a dielectric layer. Like the non-symmetric MMs based on cut-wire-pairs or electric ring resonators, the symmetrical FSS demonstrates the negative permeability at GHz frequencies. Employing the results, we designed a symmetric negative-refractive-index MM [a symmetric combined structure (SCS)], which is composed of FSSs and cross continuous wires. The MM properties of the FSS and the SCS are presented numerically and experimentally.     

Local etching of copper films by the Scanning Electrochemical Microscope in the feedback mode: A theoretical and experimental investigation

A model of the Scanning Electrochemical Microscope (SECM) as a lithographic tool is presented and used to get quantitative kinetic information from lithographic experiments. It is illustrated in the specific case of the local etching by anodic dissolution of a copper substrate by the SECM in the feedback mode. A theoretical model presents the expected profile of the etched hole in the simple case of the positive feedback behaviour. A steady-state behaviour is expected for the dimensionless shape of the hole, which depends only on the tip-substrate separation distance. The hole depth is then expected to linearly depend on the etching time. The model is then confronted to different experimental conditions where a Cu substrate is locally oxidized by a tip-electrogenerated Fe(bpy)₃³⁺ oxidant. The experiments agree with the theoretical predictions (steady-state dimensionless profile and linear evolution of the depth with time). Even though the system behaves under positive feedback, the kinetics of the etching process can readily be extracted from the hole characterization and its conversion into Faradaic yield.