Patent US5046498A successfully refreshed from Google Patents.
Patent US5334556A successfully refreshed from Google Patents.
US5334556A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for improving gate oxide integrity using low temperature oxidation during source/drain anneal
Assignee: Texas Instruments Inc
•
Filing: 1993-03-23
•
Granted: 1994-08-02
•
Expires: 2013-03-23
Abstract
Abstract A method of annealing a partially fabricated semiconductor device which comprises the steps of annealing a partially fabricated semiconductor device in an atmosphere of an inert gas and an oxidizing gas. The inert gas is preferably one of nitrogen and argon and the oxidizing gas is preferably one or more of oxygen, hydrogen chloride and nitrogen trifluoride. The oxidizing gas is from about 1 to about 10% by volume of the atmosphere. The annealing step comprises maintaining the partially fabricated semiconductor device at a first temperature, preferably about 700° C., for a first time period, preferably about 20 minutes, ramping up the temperature at a rate to a second temperature, preferably about 800° C., maintaining the second temperature for a second time period, preferably about 20 minutes, ramping up the temperature at a rate, preferably about 10° C./minute, to a third temperature, preferably about 900° C. maintaining the third temperature for a third time period, preferably about 45 minutes, ramping down the temperature at a rate, preferably about 3° C./minute, to a fourth temperature, preferably about 800° then maintaining the fourth temperature for a fourth time period while maintaining the oxidizing gas in the atmosphere only during at least one of the first time period, the first ramping up, the second time period, the second ramping up, the ramping down or the fourth time period.
Inventors
- 👤 Richard L. Guldi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 02:29
CPC Classifications
H; H10; H10P; H10P30/00; H10P30/20; H10P30/21; H10D; H10D30/00; H10D30/01; H10D30/021; H10D30/0223; H10D30/0227; H10P30/202; H10P30/204; H10P30/28; Y; Y10; Y10S; Y10S148/00; Y10S148/003; Y10S438/00; Y10S438/909
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
133 words
A method of improving gate oxide integrity of a partially fabricated semiconductor device, comprising the steps of: (a) providing a partially fabricated semiconductor device by the steps of: (i) providing a semiconductor substrate having a moat region delineated by a field oxide; (ii) forming a gate oxide in said moat region; (iii) forming a polysilicon gate over said gate oxide layer; and (iv) forming spaced apart source and drain regions adjacent said polysilicon gate; and (b) annealing said partially fabricated semiconductor device in an atmosphere of an inert gas and an oxidizing gas at a temperature commencing from about 600° C. and gradually ramped up to about 900° C.; and (c) further annealing said partially fabricated semiconductor device in an atmosphere of an inert gas when reaching said temperature of about 900° C.
Claim 2
Independent Claim
133 words
A method of improving gate oxide integrity of a partially fabricated semiconductor device, comprising the steps of: (a) providing a partially fabricated semiconductor device by the steps of: (i) providing a semiconductor substrate having a moat region delineated by a field oxide; (ii) forming a gate oxide in said moat region; (iii) forming a polysilicon gate over said gate oxide layer; and (iv) forming spaced apart source and drain regions adjacent said polysilicon gate; and (b) annealing said partially fabricated semiconductor device in an atmosphere of an inert gas and an oxidizing gas at a temperature commencing from about 600° C. and gradually ramped up to about 900° C.; and (c) further annealing said partially fabricated semiconductor device in an atmosphere of an inert gas when reaching said temperature of about 900° C.
Claim 3
Dependent Claim
22 words
The method of claim 1 wherein said inert gas is taken from the group consisting of nitrogen, argon or a combination thereof.
Claim 4
Dependent Claim
29 words
The method of claim 1 wherein said oxidizing gas is oxygen, further including adding to the ambient from about 0.01% to about 10% nitrogen trifluoride, fluorine or hydrogen chloride.
Claim 5
Dependent Claim
29 words
The method of claim 1 wherein said oxidizing gas is oxygen, further including adding to the ambient from about 0.01% to about 10% nitrogen trifluoride, fluorine or hydrogen chloride.
Claim 6
Dependent Claim
21 words
The method of claim 1 wherein said oxidizing gas is from about 1 to about 10% by volume of said atmosphere.
Claim 7
Dependent Claim
21 words
The method of claim 2 wherein said oxidizing gas is from about 1 to about 10% by volume of said atmosphere.
Claim 8
Dependent Claim
21 words
The method of claim 3 wherein said oxidizing gas is from about 1 to about 10% by volume of said atmosphere.
Claim 9
Dependent Claim
21 words
The method of claim 4 wherein said oxidizing gas is from about 1 to about 10% by volume of said atmosphere.
Claim 10
Dependent Claim
119 words
The method of claim 1 wherein said step of annealing comprises the steps of maintaining said partially fabricated semiconductor device at a first temperature for a first time period, ramping up said temperature at a rate to a second temperature, maintaining said second temperature for a second time period, ramping up said temperature at a rate to a third temperature, maintaining said third temperature for a third time period, ramping down said temperature at a rate and then maintaining said temperature for a fourth time period while maintaining said oxidizing gas in said atmosphere only during at least one of said first time period, said second time period, said fourth time period, said ramping up or said ramping down.
Claim 11
Dependent Claim
119 words
The method of claim 2 wherein said step of annealing comprises the steps of maintaining said partially fabricated semiconductor device at a first temperature for a first time period, ramping up said temperature at a rate to a second temperature, maintaining said second temperature for a second time period, ramping up said temperature at a rate to a third temperature, maintaining said third temperature for a third time period, ramping down said temperature at a rate and then maintaining said temperature for a fourth time period while maintaining said oxidizing gas in said atmosphere only during at least one of said first time period, said second time period, said fourth time period, said ramping up or said ramping down.
Claim 12
Dependent Claim
119 words
The method of claim 3 wherein said step of annealing comprises the steps of maintaining said partially fabricated semiconductor device at a first temperature for a first time period, ramping up said temperature at a rate to a second temperature, maintaining said second temperature for a second time period, ramping up said temperature at a rate to a third temperature, maintaining said third temperature for a third time period, ramping down said temperature at a rate and then maintaining said temperature for a fourth time period while maintaining said oxidizing gas in said atmosphere only during at least one of said first time period, said second time period, said fourth time period, said ramping up or said ramping down.
Claim 13
Dependent Claim
119 words
The method of claim 4 wherein said step of annealing comprises the steps of maintaining said partially fabricated semiconductor device at a first temperature for a firsts time period, ramping up said temperature at a rate to a second temperature, maintaining said second temperature for a second time period, ramping up said temperature at a rate to a third temperature, maintaining said third temperature for a third time period, ramping down said temperature at a rate and then maintaining said temperature for a fourth time period while maintaining said oxidizing gas in said atmosphere only during at least one of said first time period, said second time period, said fourth time period, said ramping up or said ramping down.
Claim 14
Dependent Claim
119 words
The method of claim 5 wherein said step of annealing comprises the steps of maintaining said partially fabricated semiconductor device at a first temperature for a first time period, ramping up said temperature at a rate to a second temperature, maintaining said second temperature for a second time period, ramping up said temperature at a rate to a third temperature, maintaining said third temperature for a third time period, ramping down said temperature at a rate and then maintaining said temperature for a fourth time period while maintaining said oxidizing gas in said atmosphere only during at least one of said first time period, said second time period, said fourth time period, said ramping up or said ramping down.
Claim 15
Dependent Claim
119 words
The method of claim 6 wherein said step of annealing comprises the steps of maintaining said partially fabricated semiconductor device at a first temperature for a first time period, ramping up said temperature at a rate to a second temperature, maintaining said second temperature for a second time period, ramping up said temperature at a rate to a third temperature, maintaining said third temperature for a third time period, ramping down said temperature at a rate and then maintaining said temperature for a fourth time period while maintaining said oxidizing gas in said atmosphere only during at least one of said first time period, said second time period, said fourth time period, said ramping up or said ramping down.
Claim 16
Dependent Claim
119 words
The method of claim 7 wherein said step of annealing comprises the steps of maintaining said partially fabricated semiconductor device at a first temperature for a first time period, ramping up said temperature at a rate to a second temperature, maintaining said second temperature for a second time period, ramping up said temperature at a rate to a third temperature, maintaining said third temperature for a third time period, ramping down said temperature at a rate and then maintaining said temperature for a fourth time period while maintaining said oxidizing gas in said atmosphere only during at least one of said first time period, said second time period, said fourth time period, said ramping up or said ramping down.
Claim 17
Dependent Claim
93 words
The method of claim 9 wherein said first temperature is about 600° C., said first time period is about 30 minutes, said ramping up said temperature is at a rate of about 10° C./minute, said second temperature is about 800° C., said second time period is about 45 minutes, said third temperature is about 900° C., said third time period is about 20 minutes, said ramping down said temperature is at a rate of about 3° C./minute, said final anneal temperature is about 800° C. and said time period is about 20 minutes.
Claim 18
Dependent Claim
93 words
The method of claim 10 wherein said first temperature is about 600° C., said first time period is about 30 minutes, said ramping up said temperature is at a rate of about 10° C./minute, said second temperature is about 800° C., said second time period is about 45 minutes, said third temperature is about 900° C., said third time period is about 20 minutes, said ramping down said temperature is at a rate of about 3° C./minute, said final anneal temperature is about 800° C. and said time period is about 20 minutes.
Claim 19
Dependent Claim
93 words
The method of claim 11 wherein said first temperature is about 600° C., said first time period is about 30 minutes, said ramping up said temperature is at a rate of about 10° C./minute, said second temperature is about 800° C., said second time period is about 45 minutes, said third temperature is about 900° C., said third time period is about 20 minutes, said ramping down said temperature is at a rate of about 3° C./minute, said final anneal temperature is about 800° C. and said time period is about 20 minutes.
Claim 20
Dependent Claim
93 words
The method of claim 12 wherein said first temperature is about 600° C., said first time period is about 30 minutes, said ramping up said temperature is at a rate of about 10° C./minute, said second temperature is about 800° C., said second time period is about 45 minutes, said third temperature is about 900° C., said third time period is about 20 minutes, said ramping down said temperature is at a rate of about 3° C./minute, said final anneal temperature is about 800° C. and said time period is about 20 minutes.
Claim 21
Dependent Claim
93 words
The method of claim 13 wherein said first temperature is about 600° C., said first time period is about 30 minutes, said ramping up said temperature is at a rate of about 10° C./minute, said second temperature is about 800° C., said second time period is about 45 minutes, said third temperature is about 900° C., said third time period is about 20 minutes, said ramping down said temperature is at a rate of about 3° C./minute, said final anneal temperature is about 800° C. and said time period is about 20 minutes.
Claim 22
Dependent Claim
93 words
The method of claim 14 wherein said first temperature is about 600° C., said first time period is about 30 minutes, said ramping up said temperature is at a rate of about 10° C./minute, said second temperature is about 800° C., said second time period is about 45 minutes, said third temperature is about 900° C., said third time period is about 20 minutes, said ramping down said temperature is at a rate of about 3° C./minute, said final anneal temperature is about 800° C. and said time period is about 20 minutes.
Claim 23
Dependent Claim
93 words
The method of claim 15 wherein said first temperature is about 600° C., said first time period is about 30 minutes, said ramping up said temperature is at a rate of about 10° C./minute, said second temperature is about 800° C., said second time period is about 45 minutes, said third temperature is about 900° C., said third time period is about 20 minutes, said ramping down said temperature is at a rate of about 3° C./minute, said final anneal temperature is about 800° C. and said time period is about 20 minutes.
Claim 24
Dependent Claim
24 words
The method of claim 1 further including the step of forming a sidewall spacer on the sidewalls of said polysilicon gate prior to annealing.
Claim 25
Dependent Claim
24 words
The method of claim 4 further including the step of forming a sidewall spacer on the sidewalls of said polysilicon gate prior to annealing.
Claim 26
Dependent Claim
24 words
The method of claim 2 further including the step of forming a sidewall spacer on the sidewalls of said polysilicon gate prior to annealing.
Claim 27
Dependent Claim
24 words
The method of claim 22 further including the step of forming a sidewall spacer on the sidewalls of said polysilicon gate prior to annealing.
References Cited (Backward Citations)
JPS63119229A
Cited
JPS63114121A
Cited
US4833099A
Cited
JPH01255217A
Cited
US5210056A
Cited
US5169796A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-08-01 | 1998-01-31 | 1998-08-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-08-01 | 2002-01-31 | 2002-08-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-08-01 | 2006-01-31 | 2006-08-02 | $7700.00 | Window Closed / Lapsed |