Method of manufacturing semiconductor device
A method of manufacturing a semiconductor device includes: providing a first photoresist pattern on a wafer; measuring an overlay of the first photoresist pattern; generating a first overlay model function by a first overlay regression analysis of the measured overlay; and generating a second overlay model function by a second overlay regression analysis of a difference between the measured overlay and the first overlay model function.
1. A method of manufacturing a semiconductor device, the method comprising:
providing a first photoresist pattern on a wafer;
measuring an overlay of the first photoresist pattern;
generating a first overlay model function by a first overlay regression analysis of the measured overlay;
generating a second overlay model function by a second overlay regression analysis of a difference between the measured overlay and the first overlay model function; and
evaluating the first photoresist pattern by using a combined overlay model function of the first and second overlay model functions,
wherein, when the first photoresist pattern is good, an etching process is performed by using the first photoresist pattern.
2. The method according to claim 1 , wherein a basis of the first overlay model function is different from a basis of the second overlay model function.
3. The method according to claim 1 , wherein the first overlay model function comprises a first or lower-order term for each of a first-direction coordinate and a second-direction coordinate.
4. The method according to claim 3 , wherein the second overlay model function comprises a second or higher-order term for each of the first-direction coordinate and the second-direction coordinate.
5. The method according to claim 1 , wherein the first overlay model function comprises a second or higher-order term for each of a first-direction coordinate and a second-direction coordinate.
6. The method according to claim 5 , wherein the second overlay model function comprises a first or lower-order term for each of the first-direction coordinate and the second-direction coordinate.
7. The method according to claim 1 ,
wherein, when the first photoresist pattern is not good, the first photoresist pattern is removed.
8. The method according to claim 7 , further comprising:
after the removal of the first photoresist pattern, providing a second photoresist pattern, which is overlay-compensated by using the combined overlay model function.
9. A method of manufacturing a semiconductor device, the method comprising:
providing a first photoresist pattern on a first wafer;
measuring an overlay of the first photoresist pattern;
generating a first overlay model function by a first overlay regression analysis of the overlay;
generating a second overlay model function by a second overlay regression analysis of a difference between the measured overlay and the first overlay model function; and
providing a second photoresist pattern on a second wafer, the second photoresist pattern being overlay-compensated by the first and second overlay model functions.
10. The method according to claim 9 , wherein the first and second overlay model functions do not have a basis common to each other.
11. The method according to claim 9 , wherein the first overlay model function comprises a constant term and a first-order term.
12. The method according to claim 11 , wherein the second overlay model function comprises third or higher-order terms.
13. The method according to claim 11 , wherein an order of the highest-order term of the first overlay model function is 2.
14. A method of manufacturing a semiconductor device, the method comprising:
providing a first photoresist material layer on a wafer;
exposing the first photoresist material layer to a light pattern;
measuring an overlay of the wafer;
generating a first overlay model function by a first overlay regression analysis of the measured overlay;
generating a second overlay model function by a second overlay regression analysis of a difference between the measured overlay and the first overlay model function;
evaluating the first photoresist material layer by using a combined overlay model function of the first and second overlay model functions; and
when the first photoresist material layer is good, performing a development process on the first photoresist material layer,
wherein the first overlay model function comprises only first-order and/or lower than first-order terms and the second overlay model function comprises only second-order and/or higher than second-order terms.
15. The method according to claim 14 , wherein the measuring of the overlay comprises measuring an overlay of the exposed first photoresist material layer.
16. The method according to claim 14 , further comprising:
evaluating the first photoresist material layer by using a combined overlay model function of the first and second overlay model functions; and
when the first photoresist material layer is not good, removing the first photoresist material layer.
17. The method according to claim 16 , further comprising:
after the removing of the first photoresist material layer,
providing a second photoresist material layer onto the wafer; and
exposing the second photoresist material layer by using the combined overlay model function.
18. The method according to claim 14 , further comprising:
generating a photoresist pattern by developing the first photoresist material layer; and
performing an etching process by using the photoresist pattern,
wherein, after the performing of the etching process, the overlay is measured.