| 摘要 |
PURPOSE:To eliminate an error of measurement caused by various factors, by superposing a ripple signal on the retarding voltage of an energy analyzer to carry out both the gain control and the output signal control at a time and accordingly normalizing the analysis output signal. CONSTITUTION:An electron beam probe 2 and an energy analyzer 4 are provided, and the retarding voltage is controlled to obrain a coincidence between the analysis output signal and the level reference quantity V0. The retarding voltage at that moment is defined as the voltage at the measuring point on a sample 1. In this case, the following means are provided: an LPF13 that delivers the DC component V1 of the analysis output signal; a means 14 that controls the retarding voltage to obtain a coincidence between the filter output signal and the voltage V0; a BPF21 that delivers the ripple component of the analysis output signal in the form of a variation factor signal DELTAV1; and a means 25 that controls the gain of the analyzer 4 to obtain a coincidence between the signal DELTAV1 and the variation reference level DELTAV0. Thus both the gain control of the analyzer 4 and the output signal control are carried out at a time. |
