Method and apparatus for the production of process gas that includes water vapor and hydrogen formed by burning oxygen in a hydrogen-rich environment
View Patent ↗The aim of the invention is the simple and economical production of a hydrogen-rich process gas from water vapour and hydrogen, whereby the proportion of water vapour to hydrogen may be precisely controllable and reproducible. Said aim is achieved, with a method and device for the production of a process gas for the treatment of substrates, in particular semiconductor substrates, in which the oxygen for formation of a process gas, comprising water vapour and hydrogen, is burnt in a hydrogen-rich environment in a combustion chamber.
1. A method of treating objects, including the steps of:
providing a combustion chamber;
producing a first hydrogen-rich process gas of water vapor and hydrogen in said chamber by burning oxygen in an overstoichiometric, hydrogen-rich environment in said combustion chamber; and
conveying said first process gas into an object-treatment chamber.
2. A method according to claim 1 , which includes the further step of detecting a presence of unburned oxygen downstream of said combustion chamber.
3. A method according to claim 2 , which includes the further step of interrupting the method if unburned oxygen is detected downstream of said combustion chamber.
4. A method according to claim 2 , which includes the further step of introducing an inert gas into said first process gas if unburned oxygen is detected downstream of said combustion chamber.
5. A method according to claim 1 , which includes the further step of introducing hydrogen into said first process gas downstream of said combustion chamber.
6. A method according to claim 1 , wherein prior to burning of the oxygen, said combustion chamber is filled with pure hydrogen, and wherein oxygen is introduced for the first time for triggering the burning.
7. A method according to claim 1 , wherein to produce a second, oxygen-rich process gas, a ratio of oxygen to hydrogen in said combustion chamber is changed during the burning.
8. A method according to claim 7 , wherein during the changing between a production of the hydrogen-rich process gas and the oxygen-rich process gas, a stoichiometric burning of oxygen and hydrogen is carried out for a predetermined period of time.
9. A method according to claim 8 , which during a production of the oxygen-rich process gas, includes the step of detecting a presence of unburned hydrogen downstream of said combustion chamber.
10. A method according to claim 9 , which includes the step of interrupting the method if unburned hydrogen is detected downstream of said combustion chamber.
11. A method according to claim 9 , which includes the step of introducing an inert gas into the process gas if unburned hydrogen is detected downstream of said combustion chamber.
12. A method according to claim 7 , which includes the step of introducing additional oxygen downstream of said combustion chamber after a production of the oxygen-rich process gas.
13. A method according to claim 1 , which includes the step of blocking an oxygen supply line downstream of said combustion chamber if a hydrogen-rich process gas is produced in said combustion chamber.
14. A method according to claim 1 , which includes the step of blocking a hydrogen supply line downstream of said combustion chamber if an oxygen-rich process gas is produced in said combustion chamber.
15. A method according to claim 1 , which includes the step of introducing a further fluid into said first process gas downstream of said combustion chamber.
16. A method according to claim 1 , wherein an oxygen-rich process gas is initially produced in said combustion chamber by burning oxygen in a hydrogen-poor environment, and wherein a ratio of oxygen to hydrogen in said combustion chamber is changed for burning the oxygen in the hydrogen-rich environment.
17. A method according to claim 16 , wherein during a change from the burning of oxygen in the hydrogen-poor environment to the hydrogen-rich environment, a stoichiometric burning of oxygen and hydrogen is carried out for a predetermined period of time.
18. A method according to claim 1 , which includes the step of flushing said combustion chamber with an inert gas prior to the burning process.
19. A method according to claim 1 , wherein said first process gas is used for a thermal treatment of at least one semiconductor wafer, and wherein within a treatment cycle a change is made between the hydrogen-rich process gas and an oxygen-rich process gas.
20. A method according to claim 19 , wherein a concentration of hydrogen or oxygen in said process gas is changed during a thermal treatment cycle.
21. A method according to claim 1 , wherein said first process gas is used for a thermal treatment of at least one semiconductor wafer, and wherein during successive thermal treatment cycles, a change is made between the hydrogen-rich and an oxygen-rich process gas.
22. A method according to claim 21 , wherein a concentration of hydrogen or oxygen in said process gas is changed during a thermal treatment cycle.
23. An apparatus for the treatment of objects and for the production of a process gas for the treatment of the objects, comprising:
at least one process chamber for the thermal treatment of objects;
a burner;
a combustion chamber provided in said burner;
at least one oxygen supply line, and at least one hydrogen supply line, into said combustion chamber;
an ignition unit for igniting an oxygen/hydrogen mixture in said combustion chamber;
a control unit that is controllable in such a way that for a formation of a process gas comprising water vapor and hydrogen, oxygen is ignited in an overstoichiometric, hydrogen-rich environment and is completely burned; and
an outlet conduit that communicates with said burner, wherein said outlet conduit is connected to at least one of said at least one process chamber.
24. An apparatus according to claim 23 , wherein at least one of an oxygen sensor and a hydrogen sensor are disposed in said outlet conduit of said burner.
25. An apparatus according to claim 23 , wherein a hydrogen line is connected with said outlet conduit of said burner.
26. An apparatus according to claim 25 , wherein an oxygen line communicates with said outlet conduit of said burner.
27. An apparatus according to claim 26 , wherein means are provided for locking said oxygen line and said hydrogen line in opposition to one another.
28. An apparatus according to claim 23 , wherein said control unit is controllable in such a way that a combustion in said combustion chamber is changed from a hydrogen-rich combustion to an oxygen-rich combustion.