Observation method and observation device

摘要

With respect to a charged particle beam device, the step size of focal point measure for executing autofocusing is optimized to a value that is optimal with respect to the spread of an approximation curve for a focal point measure distribution. The step size of focal point measure for executing autofocusing is corrected using an image feature obtained based on a layout image derived from an image obtained at a first magnification or from design data. Autofocusing is executed based on the obtained step size to carry out observation, measurement, or to image the sample under inspection.

主权项

1. A charged particle beam device having autofocusing means that obtains a plurality of images with varying focal positions by shifting a focal position in increments of a predetermined step size and estimates a focusing position based on the plurality of images, the charged particle beam device comprising:
imaging means that obtains images at a first magnification and a second magnification greater than the first magnification; focusing position analysis processing means that obtains an image feature based on a region selected from the image of the first magnification; step size determination means that obtains a step size based on the image feature obtained by the focusing position analysis processing means; and autofocus execution means that executes autofocusing at the second magnification using the step size obtained by the step size determination means.