| 摘要 |
PURPOSE:To perform accurate energy analysis by preventing the shift of energy analysis curves accompanied with the variation of heights of samples by a method wherein an off-set voltage is generated from an objective lens control voltage and then added to an analysis voltage, resulting in applying the current on an analysis grid. CONSTITUTION:If the sample 5 placed on a table in the sample chamber of a scanning type electron microscope takes the position 5B in a dotted line instead of the proper position 5A, the objective lens control voltage of a digital-analog converter (DAC)3 for the objective lens is supplied to an off-set voltage control circuit 11, resulting in the generation of the off-set voltage in a functional relation previously determined based on the experimental data, and then the voltage is supplied to an adding amplifier 10, thus added to the output of a DAC9 for the analysis voltage and accordingly impressed on the analysis grid 8. Thereby, the energy analysis curve going to shift as a dotted line can be measured as the energy analysis curve shown by a full line. |
