| 摘要 |
PROBLEM TO BE SOLVED: To provide a charged particle beam device in which a picture without any change in picture quality can be obtained even if magnification of the picture is changed. SOLUTION: In the charged particle beam device, when the magnification of a picture is changed, a control of a first picture signal quantity is carried out so that S/N measurement value may be in a prescribed range. Then, a control of a second picture signal quantity is carried out so that the picture quantity may be optimum. As a control method of the picture signal quantity, there are methods such as a method to control charged particle beam dose, a method to control acquisition time of the picture, a method to control accumulated number of sheet of the picture, a method to control detection frequency of the picture, and a method to control beam diameter. COPYRIGHT: (C)2007,JPO&INPIT
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