| 摘要 |
Disclosed are apparatus and methods for optically inspecting a voltage contrast type test structure, product circuit pattern, or the like. An optical image of a voltage contrast type test structure is generated. When the optical image has a first type of intensity pattern, it is determined that there is a defect within the test structure. When the optical image has a second type of intensity pattern, it is determined that there is no defect. The intensity patterns correspond to different voltage potential patterns that are expected to be generated if the test structure were subject to a voltage contrast inspection. That is, the first intensity pattern corresponds to a first voltage potential pattern that would be generated during a voltage contrast inspection when there is a defect present, and the second intensity pattern, corresponds to a second voltage potential pattern that would be generated during a voltage contrast inspection when there is not defect present. For example, if the test structure was expected to have a same voltage potential during a voltage contrast inspection, the test structure may be expected have a corresponding uniform intensity value during an optical inspection. When this example test structure has an intensity pattern which includes different intensity values, it is determined that there is a defect within the test structure. |
