扫描探针显微学中的云纹方法

在扫描探针显微镜（SPM）的扫描过程中，由SPM的扫描线与物质表面周期性晶格结构进行干 涉可以形成纳米云纹图像.采用高取向热解石墨（HOPG）和云母作为试件，分别对扫描隧道 显微镜（STM）和原子力显微镜（AFM）云纹进行了研究，实验结果与理论分析完全一致.SPM 纳米云纹法在纳米测量和表征方面具有较大的应用前景. 关键词： 云纹 SPM 晶格栅线 纳米测量     

原子力显微扫描云纹法的相移技术研究

提出一种原子力显微镜扫描云纹法的相移新技术 ,运用原子力显微镜的压电扫描头作为相移元件 ,对所得云纹图像可进行 0 - 2 π范围内的四步相移。对该方法的测量原理和实验技术进行了详细的阐述。作为典型实验和应用实例 ,分别对由全息光栅和含热变形的电子封装试件栅形成的云纹进行相移分析。成功的实验结果表明 ,该方法是可行的 ,为微米云纹方法的条纹处理提供了一种新途径。该方法可望在微观变形的云纹法测量中发挥积极作用     

扫描隧道显微镜纳米云纹法的实验研究

提出了应用扫描隧道显微镜(STM)纳米云纹法测量面内位移的原理。测量中,把扫描隧道显微镜的探针扫描线作为参考栅,把物质原子晶格栅结构作为试件栅,对这两组栅线干涉形成的云纹进行了纳米级变形测量。对扫描隧道显微镜纳米云纹的形成原理及测量方法进行了详尽的讨论,并运用该方法对高定向裂解石墨(HOPG)的纳米级变形虚应变进行了测量研究,得到了随扫描范围变化的虚应变场,并与理论值进行了比较。     

AFM制作纳米光栅技术研究

在扫描探针纳米加工技术的基础上,提出了利用原子力显微镜(AFM)来制作高频光栅的新工艺。利用AFM硅制探针,在接触模式下对光盘(聚碳酸酯材料)进行刻划试验。对刻划光栅的工艺参数进行优化,得到了纳米量级光栅。并将刻划所得光栅应用于数字云纹法,与数字参考栅干涉形成微/纳米数字云纹。实验结果表明,该法所制得的光栅可以应用于实际变形的测量。     

高分辨显微镜纳米云纹方法的发展与应用

介绍了近年来发展的纳米云纹法及其新的应用。这些方法是基于原子力显微镜、扫描隧道显微镜和透射电子显微镜的原理提出来的。纳米云纹法能够对物体的微/纳观变形提供定量的分析。详述了这些方法的测量原理和实验技术,并进行了新的应用研究。实验结果论证了这些方法的可行性,并证实了这些方法具有纳米级的位移测量灵敏度。     

TEM纳米云纹法测量纳米碳管变形

提出了透射电子显微镜(TEM)纳米云纹法的新技术,首次将该方法用于单根单壁碳纳米管的残余变形测量。纳米云纹由计算机显示器扫描线与碳纳米管束TEM图像干涉而成。该方法具有纳米级空间分辨率,可直接测量碳纳米管的力学性能。对TEM纳米云纹法的原理进行了详细的阐述,并利用不同管径的单壁碳管束产生了云纹。对直径为7.5nm的弯曲碳管束的残余变形进行测量,直接得到了其中一根直径为1.0nm的单壁碳管的残余变形场。实验结果证明了该方法的可行性。该方法为纳米尺度的碳管力学性能测量提供了新途径。     

激光扫描共聚焦显微镜中云纹法的实验研究

将激光扫描共聚焦显微镜与实验力学中的云纹法相结合,提出了激光扫描共聚焦显微镜云纹法并对其进行了实验研究.实验中以激光扫描共聚焦显微镜的扫描线作为虚拟参考栅,以1 200 lines/mm的全息光栅作为试件栅,这两组栅线相干涉形成云纹条纹.对激光扫描共聚焦显微镜中云纹的形成原理和出现条件进行了讨论,对实验结果与理论分析进行了比较.结果表明,激光扫描共聚焦显微镜云纹法是真实可行的.由于该方法无需干涉系统且对测量环境无特殊要求,因此有望在待测物体表面微米量级变形观察和测量上得到应用.     

二维云母界面对晶体定向生长的诱导作用研究

利用原子力显微镜(AFM)研究了云母衬底对氯化钠晶体定向生长的诱导作用,发现云母表面的氯化钠按照夹角60°左右的方向或者相互平行、相互垂直的方向生长,此角度分布规律与文献中生物分子在云母表面诱导下组装的纳米结构的夹角相互一致。说明云母表面不但可以用于诱导生物分子按照一定的方向进行自组装,还可以用于诱导无机晶体按照特定的方向进行组装生长。     

用激光加工硅钢片降低铁损残余变形的云纹干涉法测量研究

应用双镀层高温高频光栅和云纹干涉法对激光加工硅钢片降低铁损的残余变形进行了测量研究。分别对采用ＣＯ２连续激光和ＹＡＧ脉冲激光不同参数处理后硅钢片表面的残余变形进行了测量，对双镀层Ｃｒ－Ｃｒ光栅的制作方法、云纹干涉法测量残余变形的原理进行了讨论。实验结果表明，硅钢片在激光加工后，试件表面产生负性残余应变是细化磁畴，降低铁损的直接原因     

扫描离子束云纹法

提出了一种在微米尺度下测量物体面内位移的新型扫描离子束云纹法。对该方法的测量原理以及变形测量的精度进行了阐述。以平行云纹和转角云纹为典型实验对该方法的测量精度进行了检验。该方法成功地应用于微电子系统结构在去除SiO2牺牲层后的残余变形测量。实验结果证实了该方法的可行性。     

双成象单元扫描隧道显微镜与原子尺纳米计量技术

研制了双成象单元扫描隧道显微镜(STM),可同时对参考样品的原子晶格和被测样品扫描成象.计数原子晶格的数目,即可精确测定被测样品图象的尺度,以原子尺方式实现严格的纳米计量.本文介绍双成象单元的STM的原理和仪器系统,讨论原子尺纳米计量的可行性,给出被测样品图象的纳米计量结果.     

Effects of Substrate Hydrophobicity/Hydrophilicity on Height Measurement of Individual DNA Molecules

Effects of substrate hydrophobicity/hydrophilicity on height measurement of individual ds-DNA molecules are investigated with tapping mode atomic force microscopy （TMAFM） and vibrating mode scanning polarization force microscopy （VSPFM）. The measured heights of ds-DNA on hydrophobic highly oriented pyrolytic graphite （HOPG） are remarkably less than those on hydrophilic bare mica and Ni^2＋ treated mica in both TMAFM and VSPFM. By analysing the results, we propose that the hydrophobicity/hydrophilicity of substrate can greatly influence the height measurement of DNA molecules.     

Folding and cracking of graphene oxide sheets upon deposition

Graphene Oxide (GO) sheets, suspended in an aqueous solution, were deposited on freshly cleaved highly oriented pyrolytic graphite (HOPG) and studied using Raman spectroscopy, atomic force microscopy (AFM) and scanning tunneling microscopy (STM). AFM phase imaging shows a distinct contrast between GO and the underlying HOPG substrate. Raman spectroscopy clearly showed the presence of GO sheets on the top of HOPG substrate. The AFM and STM images also reveal wrinkling, folding, and tearing of individual GO sheets after depositing onto an HOPG substrate. We have also observed a distinct cracking of a GO sheet after folding. We attribute this new cracking phenomenon to a weakening of C–C bonds during the oxidation of a graphene sheet.     

原子力显微镜扫描成像DNA分子

采用Mg2+处理DNA、APTES或戊二醛修饰云母表面、DNA拉直方法制备了λ-DNA及DNA-组蛋白复合物样品.室温下原子力显微镜以轻敲模式在空气中扫描样品成像.实验结果表明:AFM扫描成像的效果与样品的制备方法有关,同时也受操作因素影响.     

原子力显微镜

研制成功了一台使用光学偏转法检测的原子力显微镜，通过对云母、光栅、光盘等样品的观测证明仪器达到原子分辨率，最大扫描范围可达７μｍ×７μｍ。文中将对这台原子力显微镜的原理、结构及一些应用结果进行讨论。     

Structure modification of highly ordered pyrolytic graphite by Ar plasma beam scanning at different incident angles

The surface of highly ordered pyrolytic graphite (HOPG) was modified by Ar plasma beam scanning at a controllable angle of incidence. The characteristics of plasma modified HOPG were investigated by atomic force microscope (AFM), micro-Raman, X-ray photoemission spectroscopy (XPS), and grazing incident angle of X-ray diffraction (GIAXRD). A smooth surface of HOPG can be obtained by adjusting the incident angles of Ar plasma beam scanning. The surfaces of HOPG become smoother with increasing angle of incidence after Ar plasma beam scanning. Raman spectra indicate that the plasma beam scanning breaks the hexagonal structures of sp² C=C bonds near the surface of HOPG. The broken hexagonal network structures can form C–O bonds that increase the amount of oxygen on the surface of HOPG, supported by C_1s and O_1s XPS spectra. GIAXRD data support that the co-existence of both crystalline structures of 2H and 3R in HOPG. The carbon bond breaking in 2H and 3R is different and depends on the angle of incidence. Most broken carbon bonds form damaged aromatic rings near the surface of HOPG.     

Laser scribing on HOPG for graphene stamp printing on silicon wafer

Highly oriented pyrolytic graphite (HOPG) was scribed by pulsed laser beam to produce square patterns. Patterning of HOPG surface facilitates the detachment of graphene layers during contact printing. Direct HOPG-to-substrate and glue-assisted stamp printing of a few-layers graphene was compared. Printed graphene sheets were visualized by optical and scanning electron microscopy. The number of graphene layers was measured by atomic force microscopy. Glue-assisted stamp printing allows printing relatively large graphene sheets (40×40 μm) onto a silicon wafer. The presented method is easier to implement and is more flexible than the majority of existing ways of placing graphene sheets onto a substrate.