Patent US5633212A successfully refreshed from Google Patents.
US5633212A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pyrogenic wet thermal oxidation of semiconductor wafers
Assignee: Yamaha Corp
•
Filing: 1994-07-22
•
Granted: 1997-05-27
•
Expires: 2014-07-22
Abstract
Abstract An oxidizing gas containing water vapor generated by hydrogen combustion is introduced from an external gas burner via gas supply pipes into the upper space of a process tube surrounded by a heater, and exhausted from the lower part of the process tube. Until the flame of hydrogen burnt in the external gas burner becomes stable, a dilute gas such as N 2 is introduced into the upper space of the process tube via other gas supply pipes so as to suppress the initial oxidation. Suppressing the initial oxidation may also be performed by bypassing an oxidizing gas from the external gas burner to an exhaust system while introducing a non-oxidizing gas such as N 2 into the upper space of the process tube.
Inventors
- 👤 Tomohiro Yuuki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 03:40
CPC Classifications
H; H10; H10P; H10P72/00; H10P72/30; H10P72/34; H10P72/3411; H10P72/3412; C; C30; C30B; C30B33/00; C30B33/005; H10P14/00; H10P14/60; H10P14/63; H10P14/6302; H10P14/6304; H10P14/6306; H10P14/6308; H10P14/6309; H10P72/04; H10P72/0431; H10P72/0434; H10P72/33; H10P72/3312; H10P14/6322
Claims Analysis
Total Claims: 30
Claim 1
Independent Claim
144 words
A method of manufacturing a semiconductor device using a furnace system including a main furnace chamber and an external combustion chamber connected to the main furnace chamber upstream of the main furnace chamber, the method comprising the steps of: (a) purging the furnace system with an inert gas; (b) loading semiconductor wafers into the main furnace chamber; (c) activating heating of the external combustion chamber; (d) introducing oxygen into the furnace system; (e) stopping the purging with the inert gas while providing dilute gas into the main furnace chamber without the dilute gas passing through the external combustion chamber; (f) introducing hydrogen into the furnace system while maintaining the introduction of oxygen; (g) stopping the heating of the external combustion chamber; and (h) raising flow rates of the oxygen and the hydrogen to a desired level while stopping the provision of the dilute gas.
Claim 2
Independent Claim
144 words
A method of manufacturing a semiconductor device using a furnace system including a main furnace chamber and an external combustion chamber connected to the main furnace chamber upstream of the main furnace chamber, the method comprising the steps of: (a) purging the furnace system with an inert gas; (b) loading semiconductor wafers into the main furnace chamber; (c) activating heating of the external combustion chamber; (d) introducing oxygen into the furnace system; (e) stopping the purging with the inert gas while providing dilute gas into the main furnace chamber without the dilute gas passing through the external combustion chamber; (f) introducing hydrogen into the furnace system while maintaining the introduction of oxygen; (g) stopping the heating of the external combustion chamber; and (h) raising flow rates of the oxygen and the hydrogen to a desired level while stopping the provision of the dilute gas.
Claim 3
Dependent Claim
15 words
A method according to claim 1, wherein the main furnace chamber is a vertical type.
Claim 4
Dependent Claim
12 words
A method according to claim 1, wherein the inert gas is nitrogen.
Claim 5
Dependent Claim
12 words
A method according to claim 1, wherein the dilute gas is nitrogen.
Claim 6
Dependent Claim
24 words
A method according to claim 1, wherein the inert gas and the dilute gas are selected from a group consisting of argon and helium.
Claim 7
Dependent Claim
25 words
A method according to claim 1, wherein in the step (f), flow rates of the hydrogen and the oxygen are about 3 liters per minute.
Claim 8
Dependent Claim
27 words
A method according to claim 1, wherein the dilute gas is nitrogen and the nitrogen gas is provided from an upper portion of the main furnace chamber.
Claim 9
Independent Claim
156 words
A method of oxidizing a semiconductor substrate using a furnace system including a main furnace, a sub-furnace, a first valve connected between the main furnace and the sub-furnace, and a second valve connected to the sub-furnace to exhaust gas from the sub-furnace, comprising the steps of: (a) purging the furnace system with an inert gas supplied to the sub-furnace; (b) loading the semiconductor substrate into the main furnace; (c) activating a heater provided with the sub-furnace; (d) introducing oxygen into the sub-furnace while opening the second valve and closing the first valve; (e) simultaneously with the step (d), stopping the purging with the inert gas while providing dilute gas into the main furnace; (f) following the step (e), introducing hydrogen into the sub-furnace while maintaining the introduction of oxygen; (g) stopping the heater; and (h) raising flow rates of the oxygen and the hydrogen to a desired level while stopping the provision of the dilute gas.
Claim 10
Independent Claim
156 words
A method of oxidizing a semiconductor substrate using a furnace system including a main furnace, a sub-furnace, a first valve connected between the main furnace and the sub-furnace, and a second valve connected to the sub-furnace to exhaust gas from the sub-furnace, comprising the steps of: (a) purging the furnace system with an inert gas supplied to the sub-furnace; (b) loading the semiconductor substrate into the main furnace; (c) activating a heater provided with the sub-furnace; (d) introducing oxygen into the sub-furnace while opening the second valve and closing the first valve; (e) simultaneously with the step (d), stopping the purging with the inert gas while providing dilute gas into the main furnace; (f) following the step (e), introducing hydrogen into the sub-furnace while maintaining the introduction of oxygen; (g) stopping the heater; and (h) raising flow rates of the oxygen and the hydrogen to a desired level while stopping the provision of the dilute gas.
Claim 11
Dependent Claim
14 words
A method according to claim 8, wherein the main furnace is a vertical type.
Claim 12
Dependent Claim
12 words
A method according to claim 8, wherein the inert gas is nitrogen.
Claim 13
Dependent Claim
12 words
A method according to claim 8, wherein the dilute gas is nitrogen.
Claim 14
Dependent Claim
25 words
A method according to claim 8, wherein in the step (f), flow rates of the hydrogen and the oxygen are about 3 liters per minute.
Claim 15
Independent Claim
101 words
A method of oxidizing semiconductor wafers using a furnace system including a main furnace and a sub-furnace connected to the main furnace upstream of the main furnace, the method comprising the steps of: (a) providing a mixture of oxygen and hydrogen into the main furnace through the sub-furnace; (b) separately providing a dilute gas, different from the mixture, into the main furnace externally of the sub-furnace; (c) after the step (b), starting combustion of the mixture in the sub-furnace, thereby producing a hydrogen flame; and (d) continuing the providing of said dilute gas at least until said hydrogen flame is stabilized.
Claim 16
Independent Claim
101 words
A method of oxidizing semiconductor wafers using a furnace system including a main furnace and a sub-furnace connected to the main furnace upstream of the main furnace, the method comprising the steps of: (a) providing a mixture of oxygen and hydrogen into the main furnace through the sub-furnace; (b) separately providing a dilute gas, different from the mixture, into the main furnace externally of the sub-furnace; (c) after the step (b), starting combustion of the mixture in the sub-furnace, thereby producing a hydrogen flame; and (d) continuing the providing of said dilute gas at least until said hydrogen flame is stabilized.
Claim 17
Dependent Claim
25 words
A method according to claim 13, wherein in the step (a), flow rates of the oxygen and the hydrogen are about 3 liters per minute.
Claim 18
Dependent Claim
12 words
A method according to claim 13, wherein the dilute gas is nitrogen.
Claim 19
Dependent Claim
18 words
A method according to claim 13, wherein in the step (c), combustion is started by a lamp heater.
Claim 20
Independent Claim
119 words
A method of oxidizing semiconductor wafers using a furnace system including a main furnace and a sub-furnace connected to the main furnace at an upstream to the main furnace, the method comprising the steps of: (a) providing a mixture of oxygen and hydrogen into the sub-furnace at a first level of flow rates; (b) starting combustion of the mixture at the first level of flow rates in the sub-furnace and providing a dilute gas into the main furnace; and (c) raising flow rates of the oxygen and the hydrogen to a second level of flow rates while stopping the dilute gas before the flow rates of the oxygen and the hydrogen reach to the second level of flow rates.
Claim 21
Independent Claim
119 words
A method of oxidizing semiconductor wafers using a furnace system including a main furnace and a sub-furnace connected to the main furnace at an upstream to the main furnace, the method comprising the steps of: (a) providing a mixture of oxygen and hydrogen into the sub-furnace at a first level of flow rates; (b) starting combustion of the mixture at the first level of flow rates in the sub-furnace and providing a dilute gas into the main furnace; and (c) raising flow rates of the oxygen and the hydrogen to a second level of flow rates while stopping the dilute gas before the flow rates of the oxygen and the hydrogen reach to the second level of flow rates.
Claim 22
Dependent Claim
25 words
A method according to claim 17, wherein in the step (a), flow rates of the oxygen and the hydrogen are about 3 liters per minute.
Claim 23
Dependent Claim
12 words
A method according to claim 17, wherein the dilute gas is nitrogen.
Claim 24
Dependent Claim
18 words
A method according to claim 17, wherein in the step (b), combustion is started by a lamp heater.
Claim 25
Dependent Claim
19 words
The method of claim 8 including the step of: (i) opening the first valve and closing the second valve.
Claim 26
Dependent Claim
13 words
The method of claim 21, wherein the main furnace is a vertical type.
Claim 27
Dependent Claim
11 words
The method of claim 21, wherein the inert gas is nitrogen.
Claim 28
Dependent Claim
11 words
The method of claim 21, wherein the dilute gas is nitrogen.
Claim 29
Dependent Claim
24 words
The method of claim 21, wherein in the step (f), flow rates of the hydrogen and the oxygen are about 3 liters per minute.
Claim 30
Dependent Claim
25 words
The method of claim 21 including the step of: (j) unloading the semiconductor substrate from the main furnace following the oxidation of the semiconductor substrate.
References Cited (Backward Citations)
US4154192A
Cited
US4217154A
Cited
US4376796A
Cited
US4599247A
Cited
US4906595A
Cited
US5234501A
Cited
US4911638A
Cited
US5154949A
Cited
US5257926A
Cited
US5388944A
Cited
US5359148A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2000-05-26 | 2000-11-25 | 2001-05-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-05-26 | 2004-11-25 | 2005-05-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-05-26 | 2008-11-25 | 2009-05-27 | $7700.00 | Window Closed / Lapsed |