Inductively coupled plasma downstream strip module

• US 20040149223A1
• Filed: 12/18/2003
• Published: 08/05/2004
• Est. Priority Date: 03/31/1998
• Status: Abandoned Application

• Current Assignee: Lam Research Corporation
• Original Assignee: Lam Research Corporation
• Inventors: Barnes, Michael S., Collison, Wenli Z., Vereb, Wayne W., Ni, Tuqiang Q., McMillin, Brian K., Berney, Butch
• Application Number:
  US10/740,717
• Publication Number:
  US 20040149223A1
• Time in Patent Office: Days
• US Class Current: 118/723IR
• CPC Class Codes: H01J 37/321 the radio frequency energy being inductively coupled to the plasma
• CPC Class Codes: H01J 37/32357 Generation remote from the workpiece, e.g. down-stream
• CPC Class Codes: H01J 37/3244 Gas supply means
• CPC Class Codes: H01L 21/67069 for drying etching

Abstract

A plasma processing module for processing a substrate includes a plasma containment chamber having a feed gas inlet port capable of allowing a feed gas to enter the plasma containment chamber of the plasma processing module during the processing of the substrate. An inductively coupled source is used to energize the feed gas and striking a plasma within the plasma containment chamber. The specific configuration of the inductively coupled source causes the plasma to be formed such that the plasma includes a primary dissociation zone within the plasma containment chamber. A secondary chamber is separated from the plasma containment chamber by a plasma containment plate. The secondary chamber includes a chuck and an exhaust port. The chuck is configured to support the substrate during the processing of the substrate and the exhaust port is connected to the secondary chamber such that the exhaust port allows gases to be removed from the secondary chamber during the processing of the substrate. A chamber interconnecting port interconnects the plasma containment chamber and the secondary chamber. The chamber interconnecting port allows gases from the plasma containment chamber to flow into the secondary chamber during the processing of the substrate. The chamber interconnecting port is positioned between the plasma containment chamber and the secondary chamber such that, when the substrate is positioned on the chuck in the secondary chamber, there is no substantial direct line-of-sight exposure of the substrate to the primary dissociation zone of the plasma formed within the plasma containment chamber.

Claims

1. A plasma processing module for processing a substrate, the plasma processing module comprising:

a) a plasma containment chamber including a feed gas inlet port capable of allowing a feed gas to enter the plasma containment chamber of the plasma processing module during the processing of the substrate;

b) an inductively coupled source capable of energizing the feed gas and striking a plasma within the plasma containment chamber, the specific configuration of the inductively coupled source causing the plasma to be formed such that the plasma includes a primary dissociation zone within the plasma containment chamber;

c) a secondary chamber separated from the plasma containment chamber by a plasma containment plate, the secondary chamber including a chuck and an exhaust port, the chuck being configured to support the substrate during the processing of the substrate and the exhaust port being connected to the secondary chamber such that the exhaust port allows gases to be removed from the secondary chamber during the processing of the substrate; and

d) a chamber interconnecting port that interconnects the plasma containment chamber and the secondary chamber, the chamber interconnecting port allowing gases from the plasma containment chamber to flow into the secondary chamber during the processing of the substrate, the chamber interconnecting port being positioned between the plasma containment chamber and the secondary chamber such that, when the substrate is positioned on the chuck in the secondary chamber, there is no substantial direct line-of-sight exposure of the substrate to the primary dissociation zone of the plasma formed within the plasma containment chamber.

2. A plasma processing module according to claim 1 wherein the feed gas inlet port and the chamber interconnecting port are connected to the plasma containment chamber such that the flow of any feed gases fed into the plasma containment chamber through the feed gas inlet port is directed substantially through the primary dissociation zone of the plasma within the plasma containment chamber.

3. A plasma processing module according to claim 1 wherein the feed gas inlet port and the chamber interconnecting port are connected to the plasma containment chamber such that the flow of any feed gases fed into the plasma containment chamber through the feed gas inlet port is caused to pass substantially through the primary dissociation zone of the plasma within the plasma containment chamber two times.

4. A plasma processing module according to claim 1 wherein the secondary chamber further includes a baffle plate having a plurality of openings formed through the baffle plate, the baffle plate being positioned within the secondary chamber above the substrate such that the plurality of openings in the baffle plate cause any gases moving through the secondary chamber and out the exhaust port to flow over the substrate in a more uniformly distributed flow pattern compared to what the flow pattern would be without the baffle plate.

5. A plasma processing module according to claim 1 wherein the plasma containment plate separating the plasma containment chamber from the secondary chamber is grounded.

6. A plasma processing module according to claim 1 wherein the module further includes an additional feed gas port, the additional feed gas port being positioned such that additional feed gases may be injected into the plasma processing module without having the additional feed gases flow through the plasma containment chamber.

7. A plasma processing module according to claim 6 wherein the additional feed gas port is connected to the secondary chamber such that additional feed gases may be injected into the secondary chamber without passing through the plasma containment chamber.

8. A plasma processing module according to claim 1 wherein the module includes an RF power supply for powering the inductively coupled source.

9. A plasma processing module according to claim 1 wherein the module includes a biasing arrangement connected to the chuck in the secondary chamber for applying a bias capable of inducing a plasma within the secondary chamber.

10. A plasma processing module according to claim 9 wherein the biasing arrangement is configured to apply a soft bias capable of inducing a plasma having a plasma density of no more than about 10⁸ ions/cm³.

11. A plasma processing module according to claim 9 wherein the biasing arrangement includes an RF power supply for applying the bias.

12. A method of processing a substrate within a plasma processing module, the method comprising the steps of:

a) providing a plasma processing module including

i) a plasma containment chamber having a feed gas inlet port capable of allowing a feed gas to enter the plasma containment chamber of the plasma processing module during the processing of the substrate,

ii) a secondary chamber,

iii) a plasma containment plate separating the plasma containment chamber from the secondary chamber, and

iv) a chamber interconnecting port that interconnects the plasma containment chamber and the secondary chamber allowing gases from the plasma containment chamber to flow into the secondary chamber during the processing of the substrate;

b) placing a substrate within the secondary chamber, the secondary chamber including a chuck and an exhaust port, the chuck being configured to support the substrate during the processing of the substrate and the exhaust port being connected to the secondary chamber such that the exhaust port allows gases to be removed from the secondary chamber during the processing of the substrate;

c) causing a feed gas to be fed into the plasma containment chamber through the feed gas inlet port;

d) using an inductively coupled source to energize the feed gas within the plasma containment chamber and strike a plasma within the plasma containment chamber, the specific configuration of the inductively coupled source causing the plasma to be formed such that the plasma includes a primary dissociation zone within the plasma containment chamber; and

e) exhausting gases from the secondary chamber through the exhaust port such that the feed gas is drawn from the plasma containment chamber through the chamber interconnecting port into the secondary chamber and out of the plasma processing module through the exhaust port, the chamber interconnecting port being positioned between the plasma containment chamber and the secondary chamber such that, when the substrate is positioned on the chuck in the secondary chamber, there is no substantial direct line-of-sight exposure of the substrate to the primary dissociation zone of the plasma formed within the plasma containment chamber.

13. A method according to claim 12 wherein the process of the method is a stripping process for stripping a resist layer from the substrate.

14. A method according to claim 13 wherein the step of feeding a feed gas into the plasma processing chamber includes the step of feeding at least one of O₂ and H₂O vapor into the plasma processing chamber.

15. A method according to claim 12 wherein the feed gas inlet port and the chamber interconnecting port are connected to the plasma containment chamber such that the flow of any feed gases fed into the plasma containment chamber through the feed gas inlet port is directed substantially through the primary dissociation zone of the plasma within the plasma containment chamber.

16. A method according to claim 12 wherein the feed gas inlet port and the chamber interconnecting port are connected to the plasma containment chamber such that the flow of any feed gases fed into the plasma containment chamber through the feed gas inlet port is caused to pass substantially through the primary dissociation zone of the plasma within the plasma containment chamber two times.

17. A method according to claim 12 wherein the secondary chamber further includes a baffle plate having a plurality of openings formed through the baffle plate, the baffle plate being positioned within the secondary chamber above the substrate such that the plurality of openings in the baffle plate cause any gases moving through the secondary chamber and out the exhaust port to flow over the substrate in a more uniformly distributed flow pattern compared to what the flow pattern would be without the baffle plate.

18. A method according to claim 12 wherein the method includes the step of grounding the plasma containment plate separating the plasma containment chamber from the secondary chamber.

19. A method according to claim 12 wherein the plasma processing module further includes an additional feed gas port positioned such that additional feed gases may be injected into the plasma processing module without having the additional feed gases flow through the plasma containment chamber and wherein the method further includes the step of injecting an additional feed gas into the plasma processing module through the additional feed gas port.

20. A method according to claim 19 wherein the additional feed gas port is connected to the secondary chamber such that the additional feed gases are injected into the secondary chamber without passing through the plasma containment chamber.

21. A method according to claim 12 wherein the module includes an RF power supply for powering the inductively coupled source.

22. A method according to claim 12 wherein the plasma processing module further includes a biasing arrangement connected to the chuck in the secondary chamber and wherein the method further includes the step of applying a bias to the biasing arrangement that is capable of inducing a plasma within the secondary chamber.

23. A method according to claim 22 wherein the step of applying a bias to the biasing arrangement includes the step of applying a soft bias to the biasing arrangement thereby inducing a plasma having a plasma density of no more than about 10⁸ ions/cm³.

24. A method according to claim 22 wherein the biasing arrangement includes an RF power supply for applying the bias.

25. A method according to claim 22 wherein

a) the process of the method is a stripping process for stripping a resist layer and various residues from the substrate,

b) the plasma processing module further includes an additional feed gas port positioned such that additional feed gases may be injected into the plasma processing module without having the additional feed gases flow through the plasma containment chamber, and

c) the method further includes the step of injecting an additional fluorine containing feed gas into the plasma processing module through the additional feed gas port.