Abstract: There is provided a charged particle beam apparatus capable of obtaining a high SN ratio with a small electron irradiation amount. The charged particle beam apparatus includes a charged particle detection device. The charged particle detection device detects an analog pulse waveform signal (110) in a detection of emitted electrons (1 event) when one primary electron enters a sample, converts the analog pulse waveform signal (110) into a digital signal (111), perform a wave height discrimination (112) with the use of a unit peak corresponding electron, and outputs the digital signal (111) as a multilevel count value.

Abstract: An object of the present invention is to realize both of the accuracy of measuring the amount of secondary electron emissions and the stability of a charged particle beam image in a charged particle beam device. In a charged particle beam device, extraction of detected signals is started by a first trigger signal, the extraction of the detected signals is completed by a second trigger signal, the detected signals are sampled N times using N (N is a natural number) third trigger signals that equally divide an interval time T between the first trigger signal and the second trigger signal, secondary charged particles are measured by integrating and averaging the signals sampled in respective division times ?T obtained by equally dividing the interval time T, and the division time ?T is controlled in such a manner that the measured number of secondary charged particles becomes larger than the minimum number of charged particles satisfying ergodicity.

Abstract: There is provided a charged particle beam apparatus capable of obtaining a high SN ratio with a small electron irradiation amount. The charged particle beam apparatus includes a charged particle detection device. The charged particle detection device detects an analog pulse waveform signal (110) in a detection of emitted electrons (1 event) when one primary electron enters a sample, converts the analog pulse waveform signal (110) into a digital signal (111), perform a wave height discrimination (112) with the use of a unit peak corresponding electron, and outputs the digital signal (111) as a multilevel count value.

Abstract: An object of the present invention is to realize both of the accuracy of measuring the amount of secondary electron emissions and the stability of a charged particle beam image in a charged particle beam device. In a charged particle beam device, extraction of detected signals is started by a first trigger signal, the extraction of the detected signals is completed by a second trigger signal, the detected signals are sampled N times using N (N is a natural number) third trigger signals that equally divide an interval time T between the first trigger signal and the second trigger signal, secondary charged particles are measured by integrating and averaging the signals sampled in respective division times ?T obtained by equally dividing the interval time T, and the division time ?T is controlled in such a manner that the measured number of secondary charged particles becomes larger than the minimum number of charged particles satisfying ergodicity.

Abstract: A focusing apparatus of electron microscope for focusing an electron beam through a focusing lens onto a sample, having a deflecting means for making the electron beam scan on the sample, an astigmatism correcting means of the electron beam, a detecting means for detecting the 2nd electrons from the sample when the sample is scanned by the electron beam, and an optimum exciting current determining means of the focusing lens. The optimum exciting current is obtained by determining the position of the centroid of an area surrounded by a curve Y=f (I) and a fixed straight line. The curve Y shows the relationship between the exciting current for the focusing lens and an electron beam radius corresponding signal which is obtained on the basis of a signal from the detecting means and inversely corresponds to a radius of the electron beam on the surface of the sample.