Patent ID: 9741526
Date: 2017-08-22
CPC Classifications: H01J

Claim:
1. A charged-particle beam apparatus comprising: a charged-particle optical column that irradiates a sample with a primary charged-particle beam; a housing that forms a part of the charged-particle beam apparatus and that has an inside thereof which is evacuated by a vacuum pump; a membrane which is able to maintain differential pressure between a space which is evacuated and a space in which the sample is disposed, and through which the primary charged-particle beam transmits or passes; a detector that detects secondary charged-particles that are obtained by irradiating the sample with the primary charged-particle beam; a distance adjusting mechanism that varies a distance between the sample and the membrane; and a control section that monitors the distance between the sample and the membrane based on a detection signal that is output from the detector or an image that is generated from the detection signal; wherein the control section detects that the distance between the sample and the membrane becomes a specific distance or becomes closer than the specific distance by brightness information or resolution information of the detection signal or brightness or resolution of an image generated from the detection signal when the primary charged-particle beam is applied by first irradiation energy; further comprising: an irradiation energy control section that varies irradiation energy of the primary charged-particle beam to the sample in at least two or more conditions; wherein the control section acquires the image of the sample from the detection signal that is obtained from the sample by applying the primary charged-particle beam by second irradiation energy that is higher than the first irradiation energy after the distance between the sample and the membrane is detected to be the specific distance or closer than the specific distance.