Quanta FEI FEG250 SEM DVIA-MB1000 — China business trip report (MB1000 P13, October 2015)

China business trip report (MB1000_P13 Set up)

Quanta feg 250 SEM

15.10.26

Depart; arrive at accommodation

15.10.27~15.10.28

MB1000_P11 Set-up and vibration-environment measurement

15.10.29

Active specification discussion

Return

Good overall performance across all axes.

The floor vibration environment was measured as vertical C-Class, horizontal X C-Class, and horizontal Y D-Class. The horizontal-axis floor vibration is especially sensitive at low frequencies.

With active isolation engaged, vibration on the top plate is E-Class on Z, X, and Y, which is satisfactory overall.

In the one-third octave band, polarity reversal above 20 Hz between base and top in all axes is judged to relate to conversational noise, pump noise, and air-conditioning.

A peak appearing on TOP that did not occur on BASE (see Attachment 2 — green-circle callout on the plotted copy) may be SEM frame resonance.

According to the customer, the image shakes at ×520000 active magnification (Attachment 3).

From inspection of the plotted data, isolator behaviour looks adequate overall, though very poor low-frequency floor conditions mean isolation is unlikely to appear perfect everywhere (Attachment 3).