| With the development of nano science and technology, theresearch on nanomaterials has been attracting considerableattention due to the important application in the wide fields ofmaterial in physics, chemistry and materials science etc. Nanomeasurement technology promotes nano science and technologyto develop deeply. Scanning Probe Microscope (SPM) system isthe most important tools used for observe and researchnanomaterials.Among the great varieties of SPMs, Atomic ForceMicroscope (AFM) is most widely used. AFM can be use toobserve and research many kinds of materials includingconductors, semiconductors, nonconductors. It is widely appliedto the analysis on the films and surface microstructure because ofits high spatial resolution and its less requirements for the surfaceof sample. The sample can be put in air, liquid or vacuum. Itperformances well, and its applicability is better.The Measurement Principium of AFM:The basic principium of AFM is: there is the tiny cantileverwhich is fixed in the instrument, and another wide a small needleis fixed. There is little force (10-6~10–8N) exists between smallneedle and sample. Because of existing of that force, the tinycantilever is produced tiny form-change. When scanning,examine trans form of tiny cantilever first to measure, thentransform to measure to output by electric voltage or electriccurrent, and pass the feedback again to continuously adjust thepoint of a needle or sample Z position of direction stalk, makethis kind of function the dint(transform scalar) keep the forcesettle constantly. By using the method of examine sample todirection Z the surface facial look for moving, and sample X, ofdirection Y moving to acquiring the image of the sample.AFM has three elementary imaging modes: contact mode,taping mode and non-contact mode.In this paper, AFM (CSPM-3000 SPM) is used as the mainmethod to study different samples with contacting mode in air atroom temperature. And we have got good surface topographyimages through the data processing.First, AFM is used to scan the samples of HAP prepared bychemical precipitation method and HAP-AL2O3 complexes (massratio is 65:35) in different sintering processes. It is observed thatgrain size distributions are not even and agglomerated particlesexist clearly on the samples' surfaces from the AFM graphs. Theconclusion dropped from the result get from AFM and laserparticle analyzer analysis is that the samples' particle sizesincrease with the sintering temperature's increasing.Then,AFM is used to scan the samples of SiO2 nanocrystal,SiO2 and carbon nanotube complexes (mass ratio is 65:35),diamond film etc. And the outcome is as following:1. SiO2 nanocrystalIt is observed that grain size distributions are better even onthe samples' surfaces from the AFM graphs. The conclusiondropped from the result get from AFM and laser particle analyzeranalysis is that the samples' particle sizes increase with thesintering temperature's increasing.2. SiO2 and carbon nanotube complexes (mass ratio is 65:35)It is observed that grain size distributions are better even onthe sample surface, but the two samples can not be recognizedfrom the AFM graphs. It is found that the particle size of thesample surface is nano magnitude.3. Diamond filmMicrostructure can be seen on the AFM graph of diamondfilm. It is found that the particle size of the film surface issubmicron magnitude.The film surface is found not smooth fromthe roughness analysis.During the test, the advantages of AFM are experienced. AndAFM have some shortages such as the scanning speed is lowerthan other microtechnique , it is difficult to seek the characteristicstructure and it requires the sample surface more even, etc.AFM is the most advanced test instrument on nanomagnitude and molecular level. And it is widely used in differentsubject fields. With the manufacturing engineering perfectingcontinuously and people mastering profoundly, AFM will displaymore function in study material surface.
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