Photomask manufacturing method and photomask
View Patent ↗According to one embodiment, a photomask manufacturing method for patterning a multilayer film into a mask pattern in the multilayer film is provided. The photomask manufacturing method includes preparing a substrate including the multilayer film provided on the substrate, obtaining an amount of position variation before and after the multilayer film is patterned if a position of the mask pattern is deviated before and after patterning the multilayer film, forming the mask pattern at a position deviated by the amount of the position variation from a target position, if the multilayer film is patterned and a pattern of the multilayer film is formed at the target position, and patterning the multilayer film with the mask pattern.
1. A method of patterning multilayer films using mask patterns provided on the multilayer films, the method comprising:
preparing a first multilayer film provided on a first substrate, the first multilayer film including first molybdenum films alternately stacked with first silicon films;
forming a first etch mask pattern on the first multilayer film;
patterning the first multilayer film to form a first resulting pattern therein using the first etch mask pattern;
measuring an amount of position variation between the first resulting pattern formed in the first multilayer film and a target pattern, the position variation being due to release of stress in the first multilayer film in response to the step of patterning the first multilayer film;
preparing a second multilayer film provided on a second substrate, the second multilayer film including second molybdenum films alternately stacked with second silicon films;
forming a second etch mask pattern on the second multilayer film at a position based on the amount of the position variation measured for the first multilayer film; and
patterning the second multilayer film to form a second resulting pattern therein using the second etch mask pattern.
2. The method according to claim 1 , wherein in the step of forming the second etch mask pattern, the second etch mask pattern is offset from a target position in a first direction opposite to a direction of the amount of the position variation measured for the first multilayer film.
3. The method according to claim 1 , wherein each of the steps of forming the first etch mask pattern and the second etch mask pattern comprises writing the respective first and second etch mask patterns onto a respective resist layer located on the respective first and second multilayer films.
4. The method according to claim 1 , wherein the step of forming the second etch mask pattern includes:
creating etch mask pattern data to be used in forming the second etch mask pattern such that the second etch mask pattern is offset from a target position in a first direction opposite to a direction of the amount of the position variation measured for the first multilayer film; and
forming the second etch mask pattern based on the etch mask pattern data.
5. The method according to claim 1 , wherein
the amount of the position variation measured for the first multilayer film is obtained from a measured result on a previously manufactured mask or an evaluation of the pattern opening area.
6. The method according to claim 1 , wherein the step of measuring the amount of the position variation comprises:
measuring the stress, or a stress distribution, of the first substrate and the first multilayer film by measuring respective positional deviations at a plurality of positions of the first substrate and the first multilayer film.
7. The method according to claim 1 , wherein the step of measuring the amount of the position variation comprises:
measuring deformation of the first substrate, which is generated by the first multilayer film formed on the first substrate, and
determining the stress and a stress distribution of the first substrate and the first multilayer film based on the measured deformation of the first substrate.
8. The method according to claim 1 ,
wherein the amount of the position variation measured for the first multilayer film is caused by stress releasing of the film multilayer film which results when portions of the first multilayer film are removed during the step of patterning thereof.
9. The method according to claim 1 , further comprising:
forming a light absorber layer on the second multilayer film, and
removing, during the patterning the second multilayer film, a portion of the light absorber layer and the second multilayer film under the portion of the light absorber layer.
10. The method according to claim 1 , further comprising:
in the step of patterning the second multilayer film, patterning a circuit pattern on the second multilayer film.
11. The method according to claim 9 , further comprising forming a light shielding frame at a location where the portion of the light absorber layer and the second multilayer film under the portion of the light absorber layer have been removed.
12. The method according to claim 1 , wherein the second substrate is a glass substrate.
13. The method according to claim 1 , wherein the second substrate includes a conductive film formed on a second surface thereof, the second surface being opposite a first surface on which the second multilayer film is formed.
14. The method according to claim 1 , further comprising forming a first layer on the second multilayer film, the first layer including ruthenium.
15. The method according to claim 14 , further comprising forming a second layer on the first layer, the second film including tantalum nitride and tantalum oxide.
16. A method of patterning multilayer films using mask patterns provided on the multilayer films, the method comprising:
preparing a first multilayer film provided on a first substrate, the first multilayer film including first molybdenum films alternately stacked with first silicon films;
forming a first etch mask pattern on the first multilayer film;
patterning the first multilayer film to form a first resulting pattern therein using the first etch mask pattern;
measuring deformation of the first substrate generated by the first multilayer film formed on the first substrate;
estimating stress and a stress distribution of the first substrate and the first multilayer film based on the measured deformation of the first substrate;
obtaining an amount of position variation between the first resulting pattern formed in the first multilayer film and a target pattern, the amount of the position variation being determined based on the estimated stress and the estimated stress distribution of the first substrate and the first multilayer film;
preparing a second multilayer film provided on a second substrate, the second multilayer film including second molybdenum films alternately stacked with second silicon films;
forming a second etch mask pattern on the second multilayer film at a position based on the amount of the position variation obtained for the first multilayer film; and
patterning the second multilayer film to form a second resulting pattern therein using the second etch mask pattern.
17. The method according to claim 16 , wherein in the step of forming the second etch mask pattern, the second etch mask pattern is offset from a target position in a first direction opposite to a direction of the amount of the position variation obtained for the first multilayer film.
18. The method according to claim 16 , wherein each of the steps of forming the first etch mask pattern and the second etch mask pattern comprises writing the respective first and second etch mask patterns onto a respective resist layer disposed on the respective first and second multilayer films.
19. The method according to claim 16 , wherein the step of forming the second etch mask pattern includes:
creating etch mask pattern data for forming the second etch mask pattern such that the second etch mask pattern is offset from a target position in a first direction opposite to a direction of the amount of the position variation obtained for the first multilayer film; and
forming the second etch mask pattern based on the etch mask pattern data.
20. The method according to claim 16 , wherein
the amount of the position variation is obtained from a measured result on a previously manufactured mask or an evaluation of the pattern opening area.
21. The method according to claim 16 , wherein the step of obtaining the amount of the position variation comprises:
measuring the stress, or a stress distribution, of the first substrate and the first multilayer film by measuring respective positional deviations at a plurality of positions of the first substrate and the first multilayer film.
22. The method according to claim 16 ,
wherein the amount of the position variation is caused by stress releasing of the first multilayer film which results when portions of the first multilayer are removed during patterning thereof.
23. The method according to claim 16 , further comprising:
forming a light absorber layer on the second multilayer film, and
removing, during the patterning the second multilayer film, a portion of the light absorber layer and the second multilayer film under the portion of the light absorber layer.
24. The method according to claim 16 , further comprising:
in the step of patterning the second multilayer film, patterning a circuit pattern on the second multilayer film.
25. The method according to claim 23 , further comprising forming a light shielding frame at a location where the portion of the light absorber layer and the second multilayer film under the portion of the light absorber layer have been removed.