| 摘要 |
PURPOSE:To prevent the breakage of a tester head or the like, by providing a discharge detecting device inside the column of the electron beam device where an electron beam probe and a LSI tester are connected with each other, thereby detecting a micro discharge so as to cutoff the feed of high voltage. CONSTITUTION:Inside an electron beam probe 1, electron beams 14 from an electron gun 14 is irradiated to a sample 10 on a tester head 11 driven by a LSI tester 12 and the secondary electron is detected by a detector 5 so that the voltage of the sample is measured. In this case, a high frequency antenna 16 as a discharge detecting means is arranged inside the column 2. Then, the high frequency signal 16a and the signal 17a passed through a delay circuit are input to a differential amplifier 18 so as to obtain the differential signal, which is compared with the reference value 20 in a comparator 19, and then the exceeding value is input as a micro discharge which is a leading discharge. Therefore, the input is allowed to cutoff the feed of the high voltage so that it is possible to prevent the breakage of the expensive tester head or the like.
|
