基于干式制冷的低温扫描探针显微镜研究进展  

Advances in dry low-temperature scanning probe microscopy system development

作　　者：黄远志 杨传浩 何颂平 马瑞松 郇庆[1] Huang Yuan-Zhi;Yang Chuan-Hao;He Song-Ping;Ma Rui-Song;Huan Qing(Nanophysics and Devices Laboratory,Institute of Physics,Chinese Academy of Sciences,Beijing 100190,China;ACME(Beijing)Technology Co.,Ltd.,Beijing 101407,China)

机构地区：[1]中国科学院物理研究所,纳米物理与器件实验室,北京100190 [2]中科艾科米(北京)科技有限公司,北京101407

出　　处：《物理学报》2024年第22期49-62,共14页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:T2125014,11927808,12004417);中国科学院关键技术研发团队项目(批准号:GJJSTD20200005)资助的课题.

摘　　要：21世纪以来,扫描探针显微镜(scanning probe microscope,SPM)在微纳尺度形貌表征、物性测量及微纳加工等领域发挥着越来越重要的作用.为了使扫描探针显微镜获得更稳定的运行环境、更高的能量分辨率,人们研发了具备超高真空(ultra high vacuum,UHV)和低温(low temperature,LT)环境的SPM系统(UHV-LT-SPM).目前,大多数的UHV-LT-SPM系统通过向连续流式低温恒温器或低温杜瓦中输送液态氦-4(4He),使SPM的温度达到约4.2 K.然而由于4He元素在自然界中含量低且因需求日益增长,导致液氦价格急剧飙升,严重影响到了4He相关低温设备的正常运行.为应对上述问题,干式制冷技术成为新一代低温技术的发展方向.在此背景下,将干式制冷技术与扫描探针显微镜相结合,搭建干式低温扫描探针显微镜,成为了目前扫描探针仪器领域的研究重点之一.本文主要从扫描探针显微镜系统设计、降温设计、减振方法以及其设备性能等方面,介绍目前已经报道的几种干式LT-SPM系统.最后总结了干式LT-SPM系统目前所遇见的问题和挑战,探讨了该技术未来的发展方向.Since the beginning of the 21st century,scanning probe microscopy(SPM)has played an increasingly important role in investigating the micro-and nanoscale surface characterization,physical property measurement,and micro/nano fabrication.To provide a more stable operating environment and higher energy resolution for SPM,researchers have developed low-temperature scanning probe microscopy(LT-SPM)systems that operate under the conditions of ultra-high vacuum and low temperature.Currently,most of LT-SPM systems have achieved temperatures around 4.2 K by supplying liquid helium-4(4He)to continuous flow cryostats or low-temperature Dewars.However,due to the low natural abundance of 4He and its increasing demand,the significant increase in the price of liquid helium has seriously affected the normal operation of 4He-based low temperature equipment.To solve this problem,dry(cryogen-free)refrigeration technology has emerged as a promising alternative to the next-generation low-temperature systems.In this context,the integration of dry refrigeration technology with SPM to construct Dry-LT-SPM systems has become a key research focus in the field of scanning probe instruments.This paper mainly discusses several reported closed-cycle Dry-LT-SPM systems,focusing on aspects such as system design,refrigeration schemes,vibration reduction methods,and overall performance.Finally,this paper summarizes the current challenges and problems faced by Dry-LT-SPM systems and explores potential future developments in this field.

关 键 词：干式制冷 低温 扫描探针显微镜 振动 

分 类 号：TH742[机械工程—光学工程]