| 摘要 |
PROBLEM TO BE SOLVED: To obtain a beam with high luminance exceeding a Langmuir limit and high emittance for achieving a multiple beam inspection device with high resolution and a high throughput. SOLUTION: An electron gun includes a flat-face cathode, a drawer electrode or an anode, and a Wehnel electrode shaped like a portion of cone. An electron gun current Ie (mA) is set by a relation with a distance Dac (mm) between a cathode and anode in a range of: 0.388/Dac-0.046≤Ie≤92.8/Dac+9.28, Dac≥3 mm, or 0.388/Dac-0.046≤Ie≤22/Dac+32.7, Dac<3 mm. Alternatively, the electron gun current Ie (mA) is limited in a numerical value (a formula abbreviated) by a relation with a cathode radius. Of the relation between luminance B and cathode current density Jc, a simulation value 571 (dashed line) and an actual measurement value 572 match each other comparatively well, and the luminance exceeds a Langmuir limit 573. COPYRIGHT: (C)2009,JPO&INPIT
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