Rapid thermal processing apparatus and methods
View Patent ↗Rapid thermal processing apparatus methods are disclosed. In a disclosed apparatus, rapid thermal processing is carried out when the residual oxygen detected by a residual oxygen detector does not exceed a predetermined tolerance level. Accordingly, it is possible to prevent the contact resistance of the wafers from increasing due to the presence of excessive oxygen.
1. A rapid thermal processing method comprising:
loading a wafer into a load lock chamber;
removing oxygen inside the load lock chamber;
detecting an amount of residual oxygen remaining in each of the load lock chamber and a rapid thermal processing chamber while the load lock chamber is open to the rapid thermal processing chamber;
comparing the detected amount of residual oxygen to a predetermined threshold;
loading the wafer onto a susceptor in the rapid thermal processing chamber if the amount of residual oxygen does not exceed the predetermined threshold, and removing at least some of the residual oxygen without moving the wafer to the rapid thermal processing chamber if the amount of residual oxygen exceeds the predetermined threshold;
rapid thermal processing the wafer in the rapid thermal processing chamber; and
cooling the rapid thermal processed wafer.
2. A rapid thermal processing method as defined in claim 1 , wherein the predetermined threshold is less than or equal to about 1.5 ppm.
3. A rapid thermal processing method as defined in claim 1 , further comprising injecting at least one of nitrogen and argon gas into the load lock chamber such that a pressure inside the load lock chamber reaches a range of about 760˜800 Torr.
4. A rapid thermal processing method as defined in claim 3 , wherein the wafer is thermally treated after injecting the at least one of the nitrogen and argon gas into the rapid thermal processing chamber such that a pressure inside of the rapid thermal processing chamber is at a range of about 760˜800 Torr.
5. A rapid thermal processing method as defined in claim 3 , wherein at least one of the nitrogen or argon gas injected into the load lock chamber has a purity degree of about 99.5%.
6. A rapid thermal processing method as defined in claim 3 , further comprising keeping the pressure inside the load lock chamber above atmospheric pressure.
7. A rapid thermal processing method as defined in claim 3 , comprising injecting nitrogen gas into the load lock chamber.
8. A rapid thermal processing method as defined in claim 3 , comprising injecting argon gas into the load lock chamber.
9. A rapid thermal processing method as defined in claim 1 , wherein a base pressure of the load lock chamber is in a range of about 1˜1000 mTorr.
10. A rapid thermal processing method as defined in claim 1 , wherein the predetermined threshold is less than or equal to about 1 ppm.
11. A rapid thermal processing method as defined in claim 1 , wherein loading the wafer into the load lock chamber further comprises:
loading a cassette holding wafers on a support plate in a shuttle chamber adjacent to the load lock chamber;
lowering the cassette on the support plate;
rotating the support plate; and
raising the cassette on the support plate into the load lock chamber.
12. A rapid thermal processing method as defined in claim 11 , further comprising isolating the load lock chamber and the shuttle chamber with the support plate.
13. A rapid thermal processing method as defined in claim 11 , further comprising replacing the wafer into the cassette after cooling the wafer.
14. A rapid thermal processing method as defined in claim 1 , further comprising removing the wafer from the rapid thermal processing chamber after rapid thermal processing the wafer.
15. A rapid thermal processing method as defined in claim 1 , further comprising opening a slit door that isolates the load lock chamber and the rapid thermal processing chamber.
16. A rapid thermal processing method as defined in claim 1 , further comprising injecting a process gas in the rapid thermal processing chamber through a gas injection line while rapid thermal processing the wafer.
17. A rapid thermal processing method as defined in claim 1 , wherein the wafer contains exposed metal film thereon.
18. A rapid thermal processing method as defined in claim 1 , wherein rapid thermal processing the wafer forms a metal silicide.
19. A rapid thermal processing method comprising:
loading a wafer into a load lock chamber;
removing oxygen inside the load lock chamber;
detecting an amount of residual oxygen remaining in each of the load lock chamber and a rapid thermal processing chamber while the load lock chamber and the rapid thermal processing chamber are in communication for loading the wafer;
comparing the detected amount of residual oxygen to a predetermined threshold;
loading the wafer onto a susceptor in the rapid thermal processing chamber if the amount of residual oxygen does not exceed the predetermined threshold, and removing at least some of the residual oxygen without moving the wafer to the rapid thermal processing chamber if the amount of residual oxygen exceeds the predetermined threshold;
rapid thermal processing the wafer in the rapid thermal processing chamber; and
cooling the rapid thermal processed wafer.
20. A rapid thermal processing method as defined in claim 19 , wherein the predetermined threshold is less than or equal to about 1.5 ppm.
21. A rapid thermal processing method as defined in claim 19 , wherein
loading the wafer into the load lock chamber further comprises:
loading a cassette holding wafers on a support plate in a shuttle chamber adjacent to the load lock chamber;
lowering the cassette on the support plate;
rotating the support plate; and
raising the cassette on the support plate into the load lock chamber.