| 摘要 |
PROBLEM TO BE SOLVED: To improve the accuracy precision of patterns by improving the precision in proximity effect correction with the exposure by the electron beams of 50 kV of acceleration voltage or over. SOLUTION: The energy Ef of the forward scattering electrons absorbed in the irradiated spot of the electron beams on a resist film is calculated. By using a line-and-space pattern in which a distance between lines (s) varies from a distance twice the backward-scattering radiusβb to a distance over twice the backward-scattering electron reaching radius rb, only the line part of a testing resist film of the same specifications as a negative resist film for pattern formation is irradiated with electron beams while varying the exposure quantity. After that, the test resist film is developed. The function D(s) of the first exposure quantity Df which is the minimum exposure quantity by which the center of the line part of the test resist film starts to remain and the second exposure quantity which is the minimum exposure quantity by which the center of the space part of the test resist film starts to remain, with the distance(s) between lines as a variable, is worked out. The third absorbing energy strength distribution by the third exposure source is calculated as (Df/D(s))×Ef and its result is utilized for the proximity effect correction.
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