ISO 11952:2014 pdf free

ISO 11952:2014 pdf free.Surface chemical analysis一Scanning-probe microscopy
In the presence of mechanical and acoustic vibrations in particular, it often is sufficient to take relatively simple countermeasures (avoidance of sound, vibration damping, sound-proofing hood or the like, see Annex C). Air currents and dust can be prevented by suitable encapsulation. Electrical interferences can,if necessary, be compensated for by appropriate measures (e.g. net filters, avoidance of ground loops).
Some external effects, such as errors due to electromagnetic disturbances, are, however, observed only in the measurements; their cause or source can then sometimes be identified or remedied, but only at great expense.
Countermeasures sometimes require careful consideration since they can also produce undesired effects.[16] For example, sound-proofing hoods often have the disadvantage that they have a high thermal insulation effect (see example in Annex C). Consequently, heat sources (especially conventional lamps) should preferably be arranged outside the casing as far as possible; active vibration damping stages with external power supply and controllers should be used. As SPMs usually also have some remaining heat sources directly in or on the instrument, the temperature inside such casings will increase.
Calibration should be carried out using certified measurement standards. The results of the preliminary investigations in Clause 6 should be taken into account when selecting the measurement standards best suited for the instrument in question in view of the measurement tasks to be performed.
These preliminary considerations also need to take account of the evaluation methods which will actually be available. The software supplied with the SPM normally differs significantly from manufacturer to manufacturer. The user is encouraged to use certified or at least validated software as far as possible, and to check any other software if it is applicable for the envisaged purpose. On the one hand, the procedures offered are in most cases inappropriately documented and, on the other hand, standardized procedures are usually not available, e.g. step height measurement in accordance with ISO 5436-1. This is why, in the following subclauses, reasonable alternatives are presented, if available, and their advantages and disadvantages discussed. ISO 11952 pdf free download.