Mechanisms of nanooxidation of Si(100) from atomic force microscopy

The machining characteristics of the nanolithographic process were studied using atomic force microscopy. Nano-oxidation experiments were conducted to investigate the influence that the different experimental parameters had on height, width and the growth rate of the nanowires and nanodots as well as upon the machining efficiency. The experimental parameters included; the applied voltage, humidity, scanning oxidization time, crystalline orientation and the shape of the probe tip. The results indicated that as the oxidization time and the applied voltage were increased, the nanowire's height and width also increased. `Also, a nanowire with increased height was produced when the humidity was higher. Finally as the probe tip began to wear and the tip's radius increased, a nanowire with a higher height and width was produced.     

海藻酸薄膜表面超微结构的原子力显微镜研究

本文采用原子力显微镜（ＡＦＭ）对海藻酸生物薄膜表面的超微结构进行了实验研究,选择出最佳观察方法。结果发现薄膜上分布不规则的微孔,其长短孔径之比大约为３：２,微孔的中心距为孔径的２倍。     

原子力显微镜在聚合物溶液结构研究中的应用

驱油用水溶性聚合物溶液的应用性能由其聚合物溶液的微观结构所决定,因此在驱油用聚合物合成及配方研究中迫切需要研究其溶液的微观结构。本文使用原子力显微镜（AFM）、环境扫描电镜（ESEM）和透射电镜（TEM）观察了水溶液中聚合物（HAWSP,AP-P4）的微观结构。研究发现常温常压下原子力显微镜观察到的聚合物网络结构图案清晰,边界分辨率高。透射电镜观察到的聚合物网络结构较模糊且网络结构有断裂现象。环境扫描电镜观测到的网络结构尺寸大小是AFM观测到的几倍甚至是十几倍。动态光散射（dynamic light scattering,DLS）结果证明AFM和TEM所观测到的聚合物结构最接近于真实结构。结果表明使用原子力显微镜在观察水溶性聚合物类样品时,能够较真实反映其微观结构。     

Acquisition of high-precision images for non-contact atomic force microscopy

The atomic force microscope (AFM) system has evolved into a useful tool for direct measurements of intermolecular forces with atomic-resolution characterization that can be employed in a broad spectrum of applications. The distance between cantilever tip and sample surface in non-contact AFM is a time-varying parameter even for a fixed sample height, and typically difficult to identify. A remedy to this problem is to directly identify the sample height in order to generate high-precision atomic-resolution images. For this, the microcantilever (which forms the basis for the operation of AFM) is modeled as a single mode approximation and the interaction between the sample and cantilever is derived from a van der Waals potential. Since in most practical applications only the microcantilever deflection is accessible, we will use merely this measurement to identify the sample height. In most non-contact AFMs, cantilevers with high-quality factors are employed essentially for acquiring high-resolution images. However, due to high-quality factor, the settling time is relatively large and the required time to achieve a periodic motion is long. As a result, identification methods based on amplitude and phase measurements cannot be efficiently utilized. The proposed method overcomes this shortfall by using a small fraction of the transient motion for parameter identification, so the scanning speed can be increased significantly. Furthermore, for acquiring atomic-scale images of atomically flat samples, the need for feedback loop to achieve setpoint amplitude is basically eliminated. On the other hand, for acquiring atomic-scale images of highly uneven samples, a simple PI controller is designed to track the desired constant sample height. Simulation results are provided to demonstrate the feasibility of the approach for both sample height identification and tracking the desired sample height.     

乙酰胆碱酯酶分子的原子力显微成像

本文研究了用原子力显微技术对乙酰胆碱酯酶进行成像的方法。在新鲜裂解的云一表面镀一层金膜,金膜与疏基丙酸（ＭＰＡ）的疏基形成Ｓ－Ａｕ键。使ＭＰＡ的游离羧基再通过碳二亚胺反应与ＡＣｈＥ的碱性氨基酸的氨基形成肽键连接,ＡＣｈＥ因而被固定于支持物表面,这样固定的ＡＣｈＥ可获得清晰成像而不脱落。     

原子力显微镜应用于铜合金表面生物沉积膜特性的研究

利用原子力显微镜(atomic force microscope,AFM)得到高分辨率的硫酸盐还原菌(sulfate-reducing bacteria,SRB)形貌,通过测量Si3N4探针与SRB细胞之间的作用力,分析SRB和腐蚀产物等物质构成的生物沉积膜与H70-1AB铜片之间吸附力的变化.结果表明,探针与SRB细胞表面的作用力为-3.81 nN～-4.16 nN,与细胞边缘的作用力为-4.07 nN～-4.80 nN,后者的作用力明显大于前者.     

碳纳米管原子力显微镜针尖的研究

本文研究了制作碳纳米管原子力显微镜针尖的方法和过程。在光学显微镜下，通过两个微工作台操纵将纯化后的多壁碳纳米管粘结在传统的原子力显微镜的Si针尖上。运用电蚀的方法优化碳管针尖的长度使其达到高分辨率的要求。我们运用制作的碳纳米管针尖在敲击模式下时G型免疫球蛋白进行扫描成像，结果显示了其典型的Y形结构，这是传统AFM的Si针尖无法获得的。     

AFM反馈系统仿真模型的建立及实验

原子力显微镜（ AFM）广泛应用于纳米尺度的成像和操纵,其较低的扫描速度严重影响了测试的效率。为此,许多研究人员通过设计先进的Z向控制算法改善系统的响应速度,达到提高扫描速度的目的,而先进的控制算法的实现首先需要对AFM的Z向反馈系统进行建模。为此,本文提出一种简单准确的系统辨识方法,通过对系统输入输出数据的分析,得到AFM的Z向反馈系统模型,并利用该模型验证先进控制算法的控制性能。实验表明该方法能为先进控制算法的设计和实现建立有效的仿真模型。     

Effect of Ar annealing temperature on SiO2/4H-SiC interface studied by spectroscopic ellipsometry and atomic force microscopy

The authors have investigated the effects of different annealing temperatures in Ar atmosphere on the SiO₂/4H-SiC interfaces by spectroscopic ellipsometry (SE) and atomic force microscopy (AFM). There is a strong correlation between the annealing temperatures and the quality of SiO₂/4H-SiC interface. Annealing at 600 °C can significantly improve the quality of SiO₂/4H-SiC interface with no transition layer. The reasons for such improvement in the quality of the SiO₂/4H-SiC interface after moderate temperature annealing at 600 °C may be explained by the formation and consumption of carbon clusters and silicon oxycarbides during annealing.     

利用原子力显微镜测量复合微胶囊静态弹性性质

用层-层组装方法制备了直径约为6μm的聚电解质多层复合微囊,并用原子力显微镜研究了微囊的弹性性质.通过用微球修饰的原子力显微镜探针对微囊加载,在空气和水环境下测童了不同刚性探针加载液体填充微囊的力曲线,利用微囊变形理论模型拟合力曲线,得到多层微胶囊的杨氏模量在90 MPa ～180 MPa之间.     

Nanoindentation characteristics on polycarbonate polymer film

The nanoindentation experiment was carried out to estimate nanomechanical characteristics of polycarbonate polymer films. Hardness, effective elastic modulus and contact stress-strain rate curve were obtained. The results showed that the effective elastic modulus and the hardness decreased as the applied load was increased. As the hold time was increased, the effective elastic modulus and the hardness also decreased. Furthermore, decreasing the loading rate also decreased the effective elastic modulus and the hardness. A power-law creep equation was obtained. When taking a log coordinate to the equation, the contact stress increased as the contact strain rate increased and has a linear appearance.     

Chemical-Mechanical polishing of parylene- n films: evaluation by X-Ray photoelectron spectroscopy and atomic force microscopy

The surface quality of parylene-N(PA-N) films, as determined by x-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM), after chemical-mechanical polishing (CMP), is influenced mostly by two factors: quality of the as-deposited film and the slurry composition. The higher the quality of the as-deposited film (more specifically, less oxygen content), the higher the quality of the polished film. The XPS and AFM results show that PA-N film polished in 1% A1₂O₃ abrasive (0.3 Μm particles), NH₄OH (2% by volume), and water, has better quality compared to the other slurries investigated. With high quality PA-N films, the film surface quality affected by CMP is relatively independent of polishing time, indicating that changes in surface chemistry occur in the initial seconds of polishing.     

Macro-scale atomic force microscope: An experimental platform for teaching precision mechatronics

A macro-scale atomic force microscope (macro-AFM) has been designed and used for teaching precision mechatronics. The macro-AFM uses a novel electromagnetic self-sensing self-actuating probe. It operates in frequency-modulation AFM (FM-AFM) mode with intermittent contact. The AFM has an imaging volume of 250 mm × 40 mm × 1 mm with a resolution of about 1 μm at 1 Hz measurement bandwidth. The macro-AFM is simple and relatively inexpensive to build. It is scaled to make motion visible to the eye and is robust for a lab environment, all of which make it an affordable and effective educational tool. The macro-AFM is used in Mechatronics (2.737), a graduate level course at MIT, where in a series of 11 laboratory exercises, the students assembled and programmed the AFM system. This article provides the design and theory used for making and controlling the macro-AFM, as well as experimental results.     

基于原子力显微镜技术的单个生物大分子压弹性研究

单个生物大分子力学性质已经成为一个新兴的研究领域,近几年来由于单分子技术的不断发展,这个领域取得了很多突破性的进展。本文介绍了基于原子力显微镜技术的几种单分子压弹性测量技术及这些技术的具体应用,同时也简要阐述了这些技术的局限性。另外对这个领域的发展也进行了初步地探讨。     

AFM的DNA样品制备技术研究

AFM应用中最为关键的一步无疑是样品的制备。本文介绍DNA样品制备的几种主要方法,通过实验发展了两种适合对DNA及其碎片进行长度测量和做统计分析的制样方法,它们分别采用APS-云母和纯云母为衬底。这两种方法不仅丰富了DNA样品制备方法,对推广AFM在生物研究中的应用也具有重要意义。     

单个人体黑素瘤细胞的原子力显微图像及拉曼光谱的研究

利用原子力显微镜对人体单个黑素瘤细胞进行扫描,观察其表面形貌,得到了人体黑素瘤细胞在原子力显微镜扫描下的清晰成像,介绍了原子力显微镜在观察单个人体黑素瘤细胞表面超微结构方面的优势.通过其原子力图像,发现黑素瘤细胞形态各异,表面粗糙,有大小不一的突起.同时给出了单个黑素瘤细胞的拉曼光谱,并对谱峰进行指认,从分子水平对黑素瘤细胞的结构进行分析.将原子力图像及拉曼散射光谱技术应用于人体黑素瘤的研究,为人类黑素瘤的早期和快速诊断提供实验依据.     

基于隧道电流检测方式的原子力显微镜纳米检测系统设计

原子力显微镜（AFM）是当前进行材料表面微观形貌观察及分析的强有力工具之一。本文主要介绍一种隧道显微镜（STM）检测方式的原子力显微镜纳米检测系统（AFM.IPC-208B）,该AFM系统设计是在STM.IPC-205B系统设计的基础上,采用隧道电流工作方式,将STM与AFM功能组合兼容。文章详细阐述了AFM.IPC-208B系统的设计原理、镜体、扫描控制以及数据采集。新设计的AFM.IPC-208B系统仍具有0.1nm的分辨率,检测范围为0～2mm×2mm,系统操作简易,工作效率高,与原STM.IPC-205B系统兼容,工作性能稳定可靠。     

女贞子多糖结构的原子力显微镜研究

水提女贞子粗多糖经过纯化得到三种多糖分别为LL-Ⅰ1,LL-Ⅰ2,LL-Ⅲ。用气相色谱对女贞子多糖组分进行分析,用原子力显微镜对其结构形态进行观测,结果表明,LL-Ⅰ1,含有鼠李糖/核糖、阿拉伯糖、甘露糖、葡萄糖和半乳糖;LL-Ⅰ2,含有鼠李糖/核糖和葡萄糖;LL-Ⅲ含有鼠李糖/核糖、阿拉伯糖、甘露糖、葡萄糖和半乳糖。原子力显微镜分析表明LL-Ⅰ1,LL-Ⅰ2,LL-Ⅲ分别不同程度的聚集成股,且具有螺旋结构。这种现象可能与聚集体的分子间相互作用和糖链间的氢键缔合有关。     

Application of atomic force microscopy to detect edge of mask contaminations that may hinder titanium silicide formation

An atomic force microscope (AFM) was used to study anomalies in the titanium disilicide formation of narrow (0.26 μm) poly lines at the edge of n+ and p+ implant masks; a special test structure was designed both for morphological and electrical evaluations. On poly lines along the borders of the n+ mask, before titanium deposition, the AFM was able to detect some material build-up exactly on the locations where the silicide is severely reduced in thickness or interrupted, as inferred by electrical data and SEM analysis on finished samples. A carbon (or nitrogen) atom knock-on during the arsenic implant was invoked to explain the observed local hindering of the silicide formation.     

利用化学力显微技术直接测定化学键的强度

本文提出了利用化学力显微镜直接测量化学键强度的实验方法,其基本思想是设法使待测化学键形成于探针与样品之间,这可以通过适当的分子设计并对探针和基底进行修饰来实现。然后在成键的环境下测量探针与样品间的粘附力,并对其进行统计处理,即可计算出键能。本文模拟硫醇在金表面上自组装摹成膜过程,即在无水乙醇溶液中现场检测镀金探针与巯基为末端的自组装膜间的粘附力。然后用ＪＫＲ粘滞理论计算实际成键个数,由此测得Ａｕ－