Patent ID: 11934095
Assignee: SAMSUNG ELECTRONICS CO., LTD.
Field: Optics (Instruments)
Classification: CPC G | IPC G

Claim 4:
5. A method of managing a critical dimension error, the method comprising:
defining, in a photomask, N openings having a width corresponding to a target critical dimension, where N is a natural number;
by irradiating light to the photomask, obtaining an intensity Ii of transmitting light at an edge of each of the N openings, where i is a natural number from 1 to N;
obtaining, a real width CDi of each of the N openings;
while, I
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      ⁢
      
        
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          I
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  ,, determining, from among Ii with respect to the natural number i which is from 1 to N, an intensity which is equal to Iave or closest to Iave as Iquasi;
while, C
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  ,, determining, from among CDi with respect to the natural number i which is from 1 to N, a real width which is equal to CDave or closest to CDave, as CDquasi;
using a graph for an opening having the real width determined as CDquasi among the N openings, the graph being obtained by setting locations in and outside the opening as a first axis and an intensity of transmitting light as a second axis perpendicular to the first axis, obtaining ILSquasi which is proportional to an inclination of a tangent to the graph at a location corresponding to an edge of the opening; and
obtaining AIMEEFi which is an aerial image mask error enhancement factor with respect to each of the N openings, according to an equation below:, A
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                ·
                
                  ILS
                  
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        [
        Equation
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