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1.
GaInAsSb是红外探测器中重要的半导体材料之一。我们用水平常压金属氧化物化学气相淀积(MOCVD)技术在n型GaSb衬底上成功地生长了GaInAsSb外延层,用PL谱、红外吸收谱、X射线衍射和扫描电子超声显微镜(ScanningElectronAcousticMicroscopy,SEAM)等实验手段对GaInAsSb外延层进行了表征。用GaInAsSb材料制作的红外探测器的光谱响应的截止波长达2.4μm,室温探测率D*达1×109cmHz(1/2)/W,2.25μm波长时的量子效率为30%。本文首次给出了GaInAsSb外延层的扫描电子超声显微镜像(SEAM像),为扫描电子超声显微镜在半导体材料方面的应用开辟了一个新的领域。  相似文献   

2.
光子扫描隧道显微镜探测场的数值模拟计算   总被引:3,自引:0,他引:3  
郭宁  夏德宽 《光电工程》1994,21(2):20-26
对光子扫描隧道显微镜(PSTM)的显微成象机理。扫描探测模型做了较为系统的分析和论述。针对具体的探测模型,利用微机编程计算PSTM探测光场的空间分布,并对场分布随扫描控制参量的变化规律进行系统的研究,得到了与实际探测结果一致的分布规律,最终为PSTM的显微成象技术提供了更为具体的理论指导。  相似文献   

3.
采用光学显微镜、扫描电子显微镜(SEM)及扫描俄歇微探针(SAM)等表面分析技术对GaAs功率场效应管(FET)源--漏烧毁失效现象进行了分析研究。SEM分析结果表明,源--漏烧毁失效的表面形貌状况较为复杂,烧伤区域的表面形态不尽一致。有源极烧毁较为严重的情况,也有漏极烧伤较严重的情况。SAM分析结果说明,源--漏烧毁FET中烧毁处附近的外表完好的源、漏条Au薄膜下欧姆接触金属薄膜层已完全消失,烧  相似文献   

4.
采用扫描电镜(SEM)和扫描俄歇微探针(SAM)对国内研制开发的微波GaAs功率FET芯片在射频测试中的烧毁进行了分析研究。探讨其烧毁机理及物理过程。  相似文献   

5.
扫描隧道显微镜(SEM)和原子力显微镜(AFM)具有原子级的极高分辨率,可在纳米尺度上获得实空间的表面微观三维菜貌,且可定量表征,因此可用来研究材料断裂与疲劳的微观机理。简要介绍STM和AFM在该领域的应用及所取得的若干进展。  相似文献   

6.
用扫描电镜(SEM)和扫描俄歇微探针(SAM)对国内研制开发的微波GaAs功率FET芯片在测试中的直流烧毁进行了分析研究,探讨了直流烧毁机理及物理过程。  相似文献   

7.
采用光学显微镜、扫描电子显微镜(SEM)及扫描俄歇微探针(SAM)等表面分析技术对GaAs功率场效应管(FET)源-漏烧毁失效现象进行了分析研究。SEM分析结果表明,源-漏烧毁失效的表面形貌状况较为复杂,烧伤区域的表面形态不尽一致。有源极烧毁较为严重的情况,也有漏极烧伤较严重的情况。SAM分析结果说明,源-漏烧毁FET中烧毁处附近的外表完好的源、漏条Au薄膜下欧姆接触金属薄膜层已完全消失,烧毁源、漏条部位表面化学元素有C、O、Ti、N和Ga,其中C、O在表层几十纳米深度内均有相当高的含量。结合分析结果,讨论了源-漏烧毁的物理机理。  相似文献   

8.
扫描近场光学显微镜的光纤探针   总被引:1,自引:0,他引:1  
刘秀梅  王佳 《光电工程》1999,26(2):25-29,34
扫描近场光学显微镜(SNOM)打破了传统光学显微镜的衍射极限分辨率,自80年代中期出现以来在10多年的时间内获得了迅速的发展,并在很多的领域有很广阔的应用前景。扫描探针的形状及针尖的大小是影响SNOM分辨率的关键因素之一。  相似文献   

9.
江月山  刘宁 《真空》1996,(5):20-22
本文介绍了超高真空扫描隧道显微镜(UHV-STM)定位系统的设计方法,并对误差进行了分析和修正。定位系统在操作范围为-560~+560nm时的定位精度达到了0.1nm,该系统性能稳定,运行可靠。达到了设计要求  相似文献   

10.
超高密度信息存储研究是纳米电子学的重要研究领域,有机功能薄膜以其独特的性质有可能成为超高密度信息存储介质之一。利用STM研究了N,N-二甲基-N-(3-硝基苯叉)-对苯二胺(DMNBPDA)有机薄膜的存储特性。高分辨扫描电子显微镜的结果表明,在扫描过程中STM对DMNBPDA薄膜表面进行了二次加工,显微Raman谱表明在加工区依然存在着DMNBPDA薄膜,并用原子力显微镜表征了加工区薄膜的表面形貌  相似文献   

11.
Scanning probe microscopy (SPM), including scanning tunneling microscopy (STM) and atomic force microscopy (AFM), has become a powerful tool in building nanoscale structures required by modern industry. In this article, the use of SPM for the manipulation of atoms and molecules for patterning nanostructures for opt-electronic and biomedical applications is reviewed. The principles and procedures of manipulation using STM and AFM-based technologies are presented with an emphasis on their ability to create a wide variety of nanostructures for different applications. The interaction among the atoms/molecules, surface, and tip are discussed. The approaches for positioning the atom/molecule from and to the desired locations and for precisely controlling its movement are elaborated for each specific manipulation technique. As an AFM-based technique, the dip-pen nanolithography is also included. Finally, concluding remarks on technological improvement and future research is provided.  相似文献   

12.
Whereas scanning probe microscopy (SPM) is highly appreciated for its nanometre scale resolution and sensitivity to surface properties, it generally cannot image solid state nanostructures under the immediate sample surface. Existing methods of cross-sectioning (focused ion beam milling and mechanical and Ar ion polishing) are either prohibitively slow or cannot provide a required surface quality. In this paper we present a novel method of Ar ion beam cross-section polishing via a beam exiting the sample. In this approach, a sample is tilted at a small angle with respect to the polishing beam that enters from underneath the surface of interest and exits at a glancing angle. This creates an almost perfect nanometre scale flat cross-section with close to open angle prismatic shape of the polished and pristine sample surfaces ideal for SPM imaging. Using the new method and material sensitive ultrasonic force microscopy we mapped the internal structure of an InSb/InAs quantum dot superlattice of 18 nm layer periodicity with the depth resolution of the order of 5 nm. We also report using this method to reveal details of interfaces in VLSI (very large scale of integration) low k dielectric interconnects, as well as discussing the performance of the new approach for SPM as well as for scanning electron microscopy studies of nanostructured materials and devices.  相似文献   

13.
This review discusses the recent progress in the application of scanning probe microscopy (SPM) in catalysis. SPM proves to be an invaluable technique for imaging catalytic surfaces and interfaces. Most SPM research is related to the structural and morphological transformation associated with catalyst preparation and use. Real-time SPM observation of surface dynamics including adsorption, diffusion and reaction, provides invaluable insights to the mechanism of catalysis. SPM is also used to shape and manipulate surfaces and surface processes. Fabrication of nanostructured catalysts, direct manipulation of adsorbed atoms and molecules and tip-mediated reactions are some examples of new SPM approach in catalyst research.  相似文献   

14.
Energy storage and conversion systems are an integral component of emerging green technologies, including mobile electronic devices, automotive, and storage components of solar and wind energy economics. Despite the rapidly expanding manufacturing capabilities and wealth of phenomenological information on the macroscopic device behaviors, the microscopic mechanisms underpinning battery and fuel cell operations in the nanometer–micrometer range are virtually unknown. This lack of information is due to the dearth of experimental techniques capable of addressing elementary mechanisms involved in battery operation, including electronic and ion transport, vacancy injection, and interfacial reactions, on the nanometer scale. In this article, a brief overview of scanning probe microscopy (SPM) methods addressing nanoscale electrochemical functionalities is provided and compared with macroscopic electrochemical methods. Future applications of emergent SPM methods, including near field optical, electromechanical, microwave, and thermal probes and combined SPM‐(S)TEM (scanning transmission electron microscopy) methods in energy storage and conversion materials are discussed.  相似文献   

15.
10 micrometer-scale scanning probe microscopy (SPM) local oxidation lithography was performed on Si. In order to realize large-scale oxidation, an SPM tip with a contact length of 15 microm was prepared by focused-ion-beam (FIB) etching. The oxidation was carried out in contact mode operation with the contact force ranging from 0.1 to 2.1 microN. The applied bias voltage was 50 V, and scanning speed was varied from 10 to 200 microm/s. The scan length was 15 microm for one cycle. The influence of contact force on the large-scale oxidation was investigated. At high contact force, the Si oxide with good size uniformity was obtained even with high scanning speed. The SPM tip with larger contact length may increase the spatial dimensions of the water meniscus between the SPM tip and sample surface, resulting in the larger dimensions of the fabricated oxide. Furthermore, the throughput of large-scale oxidation reached about 10(3) microm2/s by controlling the scanning speed and contact force of the SPM tip. It is suggested that SPM local oxidation can be upscaled by using a SPM tip with large contact length.  相似文献   

16.
Deposition of Ti was carried out by laser ablation onto hydroxyapatite porous discs in an Ar atmosphere. Ti nanoparticles were deposited onto HAp surface in order to modify its roughness and morphology as it is observed by scanning electron microscopy (SEM) and scanning probe microscopy (SPM). A homogeneous distribution of Ti over the disc surface was corroborated by elemental mapping. A comparison of the hydroxyapatite hardness before and after deposition was performed using SPM nanoindentation. Transmission Electron Microscopy (TEM) showed that the Ti nanoparticles obtained were covered by an oxygen shell. It is shown that surface modifications of the covered HAp by Ti result in better mechanical properties, reducing the possible damage to the HAp ceramic by friction or impacts as it often happens in meniscus, bone junctions and the inclusion of prosthesis for human treatments.  相似文献   

17.
The cantilever dynamics in single-frequency scanning probe microscopy (SPM) are undefined due to having only two output variables, which leads to poorly understood image contrast. To address this shortcoming, generalized phase imaging scanning probe microscopy (GP-SPM), based on broad band detection and multi-eigenmode operation, is developed and demonstrated on diamond nanoparticles with different functionalization layers. It is shown that rich information on tip-surface interactions can be acquired by separating the response amplitude, instant resonance frequency, and quality factor. The obtained data allow high-resolution imaging even in the ambient environment. By tuning the strength of tip-surface interaction, different surface functionalizations can be discerned.  相似文献   

18.
In this Progress Report, outstanding scientific applications of scanning probe microscopy (SPM) in the field of materials science and the latest technique developments are introduced and discussed. Besides being able to image the organization of matter with sub‐nanometer resolution, SPM, owing to its basic operating principle, provides the power to measure, analyze, and even quantify properties of matter on the nanometer length scale. Moreover, because of its unique potential to manipulate the organization of atoms, molecules, assemblies, or particles and to structure surfaces in a controlled fashion, in the fields of nanoscience and nanotechnology SPM has become one of the most powerful tools for preparation and analysis of nanostructures and their functionality. Because of the tremendous variety of its applications, only selected—but subjectively exceptional—topics are considered in this Progress Report, showing the full potential of SPM.  相似文献   

19.
纳米材料的表征   总被引:19,自引:0,他引:19  
阎峻 《材料导报》2001,15(4):53-55
综述了常用的纳米材料表征方法,简单介绍了其原理及应用。并对近期发展起来的SPM探针现的同科技纳米表征技术进行了介绍。  相似文献   

20.
In this paper recent developments in scanning probe microscopy ( SPM ) on organic materials are reviewed with selected examples. Presented subjects include instrumentation and particularities in connection with SPM imaging on soft organic materials. Exemplary cases of structure-properties investigations with SPM in organic materials science including amorphous polymers, polymer crystal growth effects, interface structure and stability, spinodal decomposition effects, copolymer and liquid crystal (LC) nanophase separation, LC phase transitions on a molecular scale, molecular manipulation as well as structure and properties of other organic materials are presented. Naturally, this paper cannot review all papers published about SPM on organic materials. Rather, main principles and problems as well as the strategy of probe microscopy on organic materials is elucidated with selected examples. SPM is shown to be an effective and forceful organic materials analytic tool for the materials scientist.  相似文献   

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