Scanning electron microscopes for semiconductor device inspection require high-throughput performance for full-wafer inspections. To achieve high-throughput inspections, we need to inspect a large field of view (FOV) with a high current. However, these inspection conditions cause the sample to experience electrical charging. This sample charging causes abnormal contrast and image distortions. In this paper, we show that the sample charging can be controlled by the irradiation current, and image distortion can also be minimized. We also show that the sample charging can be controlled by the voltage applied to the sample, and we explain the mechanism of charge formation.
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