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Combined electron microscopy and atom-probe field-ion microscopy
AbstractsostheScandinavian Society forElectron Microscopy
AUTOMATIC EVALUATION OF SURFACE TOPOGRAPHY BY CROSS-CORRELATION OF SEM STEREO
PAIR IMAGES Michael
Alff
Kontron D-8056
Bildanalyse Eching, BRD
Gmbh', Breslauer2,
Surface profiles are traditionally determined by the pointwise interactive measurement of shift vectors in stereo image pairs, a slow procedure unsuitable for the quantitativeevaluation of statistically meaningful surface areas. A fully automatic cross-correlation algorithm was recently implemented into the KONTRON/ZEISS image processing systems, which proves to be particularly useful for the evaluation of SEM images digitized in on-line operation with the microscope. Surface topography resulting from the pixel-wise correlation of image pairs is displayed as grey or coloured image, where heights are coded in grey levels Time requirements for the or colours. correlation of two images 512x512 depend on the size of the window used for correlation and range from 3 to 10 minutes. Selected applications in the evaluation of metal and ceramic fracture surfaces,integrated circuit topography and petrographic structure analysis axe presented. COMBINED ELECTRON MICROSCOPY PROBE FIELD-ION MICROSCOPY Hans-Olof
AND ATOM-
Department of Physics, versity of Tpchnoloqy, GClteborg, Sweden
method of microscopy is very helpful, and the combination of EM and AP-FIM is However, with combined no exception. EM and AP-FIM we understand the examin-ration of the same specimen with the two The use of the same specitechniques. men gives two important advantages: 1. Specimens containing a microstructural feature of interest can be selected for the AP-FIM, which makes AP-FIM less timeconsuming. 2. Specimens containing the microstructural feature of interest can be Epared in a controlled manner, which reduces the limit-of a small search volume. Some designs of AP-FIM specimen holders for the EM will be shown. The following examples of combined EM and AP-FIM studies will be described: 1. Grain boundary dislocations in tungsten. 2. Heavy ion damage (vacancy clusters) in tungsten. 3. MC precipitation in stabilized stainless steels. 4. Grain boundary segregation of boron in stainless steels. 5. Segregation of cobalt to carbide phase boundaries in cemented carbides. APPLICATIONS OF ANALYTICAL MICROSCOPY IN MINERALOGY
Chalmers S-412 96
Uni-
The resolution of the transmission electron microscope has improved considerably with the advent of new equipment and techniques, both in imaging (HREM) and microanalysis (AEM). In spite of this progress, better spatial resolution is still offered by atom-probe field--ion microscopy CAP-FIM), both in the imaging (FIM) and microanalytical (AP) modes. However, AP-FIM can only be used for a more limited range of materials, and the volume accessible for imaging and analysis is also considerably smaller in APFIM, where specimens must have the shape of a sharp needle. It is often found that the study of the same material with more than one _--
ELECTRON
P. E. Champness Department Manchester,
Andrbn
401
of Geology, Manchester
University of Ml3 9PL, UK
If the mechanisms of geological reactions are to be understood, their very earliest stages must be investigated. As such reaction textures are usually very small and can be chemically complex, analytical electron microscopy is the ideal tool for their investigation. A number of metamorphic reactions are being investigated in Manchester, both in natural rocks and synthetic analogues. An example is the reaction in which sillimanite, A12Si05, is produced within biotite mica, a K-rich sheet silicate. The reaction is initiated by the formation of Al203 and Si02-enriched amorphous regions along stacking faults in biotites. Excess Fe, Mq, Ti, K and Na diffuse away from the reaction site along the fault. Later crystallization of the amorphous region results in fibrous sillimanite intergrown with quartz, Si02.
AUTOMATIC EVALUATION OF SURFACE TOPOGRAPHY BY CROSS-CORRELATION OF SEM STEREO
PAIR IMAGES Michael
Alff
Kontron D-8056
Bildanalyse Eching, BRD
Gmbh', Breslauer2,
Surface profiles are traditionally determined by the pointwise interactive measurement of shift vectors in stereo image pairs, a slow procedure unsuitable for the quantitativeevaluation of statistically meaningful surface areas. A fully automatic cross-correlation algorithm was recently implemented into the KONTRON/ZEISS image processing systems, which proves to be particularly useful for the evaluation of SEM images digitized in on-line operation with the microscope. Surface topography resulting from the pixel-wise correlation of image pairs is displayed as grey or coloured image, where heights are coded in grey levels Time requirements for the or colours. correlation of two images 512x512 depend on the size of the window used for correlation and range from 3 to 10 minutes. Selected applications in the evaluation of metal and ceramic fracture surfaces,integrated circuit topography and petrographic structure analysis axe presented. COMBINED ELECTRON MICROSCOPY PROBE FIELD-ION MICROSCOPY Hans-Olof
AND ATOM-
Department of Physics, versity of Tpchnoloqy, GClteborg, Sweden
method of microscopy is very helpful, and the combination of EM and AP-FIM is However, with combined no exception. EM and AP-FIM we understand the examin-ration of the same specimen with the two The use of the same specitechniques. men gives two important advantages: 1. Specimens containing a microstructural feature of interest can be selected for the AP-FIM, which makes AP-FIM less timeconsuming. 2. Specimens containing the microstructural feature of interest can be Epared in a controlled manner, which reduces the limit-of a small search volume. Some designs of AP-FIM specimen holders for the EM will be shown. The following examples of combined EM and AP-FIM studies will be described: 1. Grain boundary dislocations in tungsten. 2. Heavy ion damage (vacancy clusters) in tungsten. 3. MC precipitation in stabilized stainless steels. 4. Grain boundary segregation of boron in stainless steels. 5. Segregation of cobalt to carbide phase boundaries in cemented carbides. APPLICATIONS OF ANALYTICAL MICROSCOPY IN MINERALOGY
Chalmers S-412 96
Uni-
The resolution of the transmission electron microscope has improved considerably with the advent of new equipment and techniques, both in imaging (HREM) and microanalysis (AEM). In spite of this progress, better spatial resolution is still offered by atom-probe field--ion microscopy CAP-FIM), both in the imaging (FIM) and microanalytical (AP) modes. However, AP-FIM can only be used for a more limited range of materials, and the volume accessible for imaging and analysis is also considerably smaller in APFIM, where specimens must have the shape of a sharp needle. It is often found that the study of the same material with more than one _--
ELECTRON
P. E. Champness Department Manchester,
Andrbn
401
of Geology, Manchester
University of Ml3 9PL, UK
If the mechanisms of geological reactions are to be understood, their very earliest stages must be investigated. As such reaction textures are usually very small and can be chemically complex, analytical electron microscopy is the ideal tool for their investigation. A number of metamorphic reactions are being investigated in Manchester, both in natural rocks and synthetic analogues. An example is the reaction in which sillimanite, A12Si05, is produced within biotite mica, a K-rich sheet silicate. The reaction is initiated by the formation of Al203 and Si02-enriched amorphous regions along stacking faults in biotites. Excess Fe, Mq, Ti, K and Na diffuse away from the reaction site along the fault. Later crystallization of the amorphous region results in fibrous sillimanite intergrown with quartz, Si02.