Method for inspecting a wafer and apparatus for inspecting a wafer
AssigneeSamsung Electronics Co., Ltd.
InventorHyo-Cheon Kang
Life of this patent
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Abstract
Disclosed are a method and apparatus for inspecting a wafer for electrical defects. A first electron beam is irradiated onto an area of the wafer including an inspection region to charge the area. A second electron beam is irradiated onto the inspection region to inspect the inspection region after focusing the second electron beam on the inspection region. A third electron beam is irradiated onto the area to discharge charges accumulated on the area. Therefore, the electrical defect of the wafer can be precisely detected with increased voltage contrasts for distinguishing the electrical defect. This method and apparatus have improved detection sensitivity and detection reliability over conventional methods.
Claims10
An apparatus for inspecting a wafer comprising:
- a chamber;
- a stage for loading the wafer, the stage being located in the chamber and horizontally movable;
- a first column for irradiating a first electron beam onto a first region of the wafer to primarily charge the first region;
- a second column for irradiating a second electron beam onto an inspection region of the wafer adjacent to the first region to inspect the inspection region;
- a third column for irradiating a third electron beam onto a second region of the wafer that is adjacent to the inspection region to discharge charges accumulated on the second region;
- a signal processing means for detecting a voltage contrast signal of secondary electrons generated from the wafer by irradiating the second electron beam;
- and
- a defect analyzing means for detecting a defect of the wafer by analyzing a signal generated from the signal processing means.
Dependencies are inferred from the claim text.