METHODS AND APPARATUSES FOR ETCH PROFILE OPTIMIZATION BY REFLECTANCE SPECTRA MATCHING AND SURFACE KINETIC MODEL OPTIMIZATION
1 Assignment
0 Petitions
Accused Products
Abstract
Disclosed are methods of optimizing a computer model which relates the etch profile of a feature on a semiconductor substrate to a set of independent input parameters (A), via the use of a plurality of model parameters (B). In some embodiments, the methods may include modifying one or more values of B so as to reduce a metric indicative of the differences between computed reflectance spectra generated from the model and corresponding experimental reflectance spectra with respect to one or more sets of values of A. In some embodiments, calculating the metric may include an operation of projecting the computed and corresponding experimental reflectance spectra onto a reduced-dimensional subspace and calculating the difference between the reflectance spectra as projected onto the subspace. Also disclosed are etch systems implementing such optimized computer models.
22 Citations
67 Claims
-
1-34. -34. (canceled)
-
35. A method of optimizing a computer model which relates an etch profile of a feature on a semiconductor substrate to a set of independent input parameters, the method comprising:
-
(a) specifying at least one model parameter to be optimized; (b) identifying multiple sets of values for a selected set of independent input parameters; (c) for each set of values specified in (b), receiving an experimental reflectance spectra generated from an optical measurement of an experimental etch process performed using the set of values specified in (b); (d) for each set of values specified in (b), generating a computed reflectance spectra from the model using the set of values specified in (b); (e) modifying a value of the model parameter specified in (a) and repeating (d) with the modified value so as to reduce a metric indicative of the differences between the experimental reflectance spectra received in (c) and corresponding computed reflectance spectra generated in (d) with respect to one or more sets of values for the selected independent input parameters specified in (b); (f) using the computer model with the modified value from (e) to determine a pattern of the lithographic mask; and (g) applying the pattern to create the lithographic mask. - View Dependent Claims (36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46)
-
-
47. A method of fabricating an etcher apparatus by optimizing a computer model that relates the etch profile of a feature on a semiconductor substrate to a set of independent input parameters, the method comprising:
-
(a) specifying at least one model parameter to be optimized; (b) identifying multiple sets of values for a selected set of independent input parameters; (c) for each set of values specified in (b), receiving an experimental reflectance spectra generated from an optical measurement of an experimental etch process performed using the set of values specified in (b); (d) for each set of values specified in (b), generating a computed reflectance spectra from the model using the set of values specified in (b); (e) modifying a value of the model parameter specified in (a) and repeating (d) with the modified value so as to reduce a metric indicative of the differences between the experimental reflectance spectra received in (c) and corresponding computed reflectance spectra generated in (d) with respect to one or more sets of values for the selected independent input parameters specified in (b); and (f) fabricating an etcher apparatus by using the computer model with the modified value from (e) to identify a reactor design for the etcher apparatus. - View Dependent Claims (48, 49, 50, 51, 52, 53, 54)
-
-
55. A method of etching a semiconductor substrate by optimizing a computer model which relates the etch profile of a feature on a semiconductor substrate to a set of independent input parameters, the method comprising:
-
(a) specifying at least one model parameter to be optimized; (b) identifying multiple sets of values for a selected set of independent input parameters; (c) for each set of values specified in (b), receiving an experimental reflectance spectra generated from an optical measurement of an experimental etch process performed using the set of values specified in (b); (d) for each set of values specified in (b), generating a computed reflectance spectra from the model using the set of values specified in (b); (e) modifying a value of the model parameter specified in (a) and repeating (d) with the modified value so as to reduce a metric indicative of the differences between the experimental reflectance spectra received in (c) and corresponding computed reflectance spectra generated in (d) with respect to one or more sets of values for the selected independent input parameters specified in (b); (f) identifying a set of etch conditions by using the computer model with the modified value from (e); and (g) etching the semiconductor substrate using the set of etch conditions. - View Dependent Claims (56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67)
-
Specification