System and method for thermal management of reticle in semiconductor manufacturing

1 . A method, comprising:

producing a data set, comprising:

exposing a plurality of workpieces using a sample reticle by an exposure tool to obtain processed workpieces;

measuring overlay values of the processed workpieces after exposure by the exposure tool;

establishing a relationship between the overlay values of the processed workpieces and a control limit of the processed workpieces; and

measuring temperature profiles of the sample reticle that are related to the overlay values of the processed workpieces after exposure by the exposure tool;

selecting a target state of a reticle based on the data set, wherein the target state is a state in which a deformation of the reticle is substantially unchanged;

regulating the reticle to reach the target state; and

performing an exposure process on a target workpiece by using the reticle.

2 . The method of claim 1 , wherein selecting the target state of the reticle comprises:

determining a target temperature of the reticle based on the data set, wherein when the reticle is at the target temperature, the deformation of the reticle is substantially unchanged by added exposure.

3 . The method of claim 2 , further comprising:

calculating a difference between the target temperature of the reticle and a current temperature of the reticle before regulating the reticle to reach the target state.

4 . The method of claim 3 , wherein regulating the reticle to reach the target state comprises:

changing the temperature of the reticle from the current temperature to substantially the target temperature.

5 . The method of claim 1 , wherein regulating the reticle to reach the target state comprises:

applying an amount of thermal energy to the reticle stored in a reticle library.

6 . The method of claim 5 , wherein a plurality of the reticles is stored in the reticle library, and applying the amount of thermal energy comprises:

applying at least two different amounts of thermal energy to the plurality of the reticles stored in the reticle library.

7 . The method of claim 1 , wherein the temperature profiles of the sample reticle are measured by a temperature sensing unit.

8 . The method of claim 1 , wherein an open ratio of the reticle is substantially equal to that of the sample reticle.

9 . A method, comprising:

calculating a target temperature of a reticle on the basis of given data from a plurality of workpieces by a computing device, wherein the given data comprises an overlay result data of the workpieces and parameters of the reticle, and the parameters of the reticle comprise a material, a light transmission rate, an open ratio, a thermal expansion coefficient, deformation profiles, or distortion maps;

matching a temperature of the reticle to the target temperature; and

performing an exposure process on a target workpiece using the reticle at the target temperature in an exposure area coupled to the computing device, wherein when the reticle is at the target temperature, the reticle reaches a state in which the reticle is substantially free of deformation as the exposure process continues.

10 . The method of claim 9 , further comprising:

before calculating the target temperature of the reticle, measuring the deformation profiles of the reticle.

11 . The method of claim 9 , wherein matching the temperature of the reticle to the target temperature comprises:

heating the reticle stored in a reticle library coupled to the computing device to reach substantially the target temperature.

12 . The method of claim 11 , further comprising after the heating:

transferring the reticle stored in the reticle library to the exposure area to conduct the exposure process.

13 . The method of claim 11 , wherein a plurality of the reticles is stored in the reticle library, the method further comprises:

heating the plurality of the reticles stored in the reticle library.

14 . The method of claim 11 , wherein the reticle is heated by using a heating component coupled to the computing device to apply an amount of thermal energy to the reticle.

15 . The method of claim 9 , further comprising before performing the exposure process:

adjusting a parameter of an exposure tool based on the reticle that is at the target temperature.

16 . A method, comprising:

exposing a workpiece by using a reticle;

measuring a temperature profile of the reticle and an overlay of the workpiece;

correlating the overlay of the workpiece to the temperature profile of the reticle;

repeating the exposing, the measuring and the correlating to generate a target overlay performance data;

determining a target state of the reticle on the basis of the target overlay performance data;

regulating a target reticle to reach a state that is similar to the target state of the reticle;

adjusting a parameter of an exposure tool on the basis of the target overlay performance data; and

performing an exposure process on a plurality of target workpieces by using the target reticle, wherein after the reticle reaches the target state, a deformation of the reticle is substantially unchanged as the exposure process continues.

17 . The method of claim 16 , wherein when repeating the exposing by using the reticle, the reticle absorbs an amount of an exposing light to reach the target state.

18 . The method of claim 16 , wherein regulating the target reticle comprises:

selecting the target reticle in a reticle library, wherein an open ratio of the target reticle is substantially equal to that of the reticle; and

applying an amount of thermal energy to the target reticle in the reticle library.

19 . The method of claim 18 , after applying the amount of thermal energy to the target reticle, further comprising:

transferring the target reticle in the reticle library to an exposure area to conduct the exposure process.

20 . The method of claim 16 , wherein after performing the exposure process on the plurality of target workpieces, the target reticle remains at the target state.