Patent US1405955A successfully refreshed from Google Patents.
Patent US5520969A successfully refreshed from Google Patents.
US5520969A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for in-situ liquid flow rate estimation and verification
Assignee: Applied Materials Inc
•
Filing: 1994-02-04
•
Granted: 1996-05-28
•
Expires: 2014-02-04
Abstract
Abstract The flow of a liquid reagent gas into a vapor deposition process chamber is adjusted in response to control information provided by a process controller. The controller executes a prescribed mathematical algorithm which utilizes first and second steady-state pressure differentials. The first pressure differential is measured during the flowing of a carrier gas into the chamber. The second pressure differential is measured after the release of the liquid reagent into the chamber.
Inventors
- 👤 Hiroshi Nishizato
- 👤 Visweswaren Sivaramakrishnan
- 👤 Jun Zhao
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 02:03
CPC Classifications
G; G05; G05D; G05D7/00; G05D7/06; G05D7/0617; G05D7/0629; G05D7/0635; G05D7/0641; G05D7/0658; C; C23; C23C; C23C16/00; C23C16/44; C23C16/448; C23C16/4481; C23C16/52; G05D11/00; G05D11/02; G05D11/13; G05D11/135
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
116 words
A method of controlling a liquid mass flow rate of a liquid reagent into a vapor deposition process chamber, the method comprising: flowing a carrier gas into the chamber; measuring a first steady-state pressure of the chamber with the carrier gas flowing into the chamber; flowing the liquid reagent into the flow of carrier gas for delivery of the liquid reagent into the chamber in a vaporized state; measuring a second steady-state pressure of the chamber while the carrier gas is delivering the vaporized liquid reagent to the chamber; computing control information from the first and second steady-state pressures; and controlling the liquid mass flow rate of the liquid reagent in response to the control information.
Claim 2
Independent Claim
116 words
A method of controlling a liquid mass flow rate of a liquid reagent into a vapor deposition process chamber, the method comprising: flowing a carrier gas into the chamber; measuring a first steady-state pressure of the chamber with the carrier gas flowing into the chamber; flowing the liquid reagent into the flow of carrier gas for delivery of the liquid reagent into the chamber in a vaporized state; measuring a second steady-state pressure of the chamber while the carrier gas is delivering the vaporized liquid reagent to the chamber; computing control information from the first and second steady-state pressures; and controlling the liquid mass flow rate of the liquid reagent in response to the control information.
Claim 3
Dependent Claim
59 words
The method of claim 1 further comprising: establishing a base pressure in the process chamber prior to flowing said carrier gas into the chamber; and after establishing a base pressure in said chamber, measuring said base pressure, wherein the computing step comprises using the measured base pressure and the first and second steady-state pressures to compute said control information.
Claim 4
Dependent Claim
54 words
The method of claim 2 wherein the computing step comprises: determining a pressure ratio, R, by computing ##EQU3## where P0 is the measured base pressure, P1 is the first steady-state pressure, and P2 is the second steady-state pressure; using R to compute a calibration constant, C; and using C to generate the control information.
Claim 5
Dependent Claim
34 words
The method of claim 3 wherein the step of using R to compute the calibration constant, C, comprises calculating ##EQU4## wherein Ro is a pressure ratio offset and Re is an expected pressure ratio.
Claim 6
Dependent Claim
28 words
The method of claim 4 further comprising determining Ro and Re during an initialization procedure that is performed using said deposition chamber prior to performing the aforementioned steps.
Claim 7
Dependent Claim
71 words
The method of claim 5 wherein the step of determining Ro comprises: determining a first pressure ratio, Re1, for a first liquid mass flow rate, Q1, of said liquid reagent into process chamber in a vaporized state; determining a second pressure ratio, Re2, for a second liquid mass flow rate, Q2, of said liquid reagent into the process chamber in a vaporized state; and computing Ro from the following relationship: ##EQU5##
Claim 8
Dependent Claim
70 words
The method of claim 3 wherein the computing step comprises: determining a pressure ratio, R, by computing ##EQU6## where P0 is the first steady-state pressure, P1 is the second steady-state pressure, and P2 is the third steady-state pressure; and comparing R to an expected pressure ratio, Re; wherein the controlling step comprises adjusting the liquid mass flow rate if R deviates from Re by more than a predetermined threshold amount.
Claim 9
Dependent Claim
31 words
The method of claim 7 wherein the controlling step further comprises refraining from adjusting the liquid mass flow rate if R deviates from Re by less than the predetermined threshold amount.
Claim 10
Dependent Claim
67 words
The method of claim 1 wherein the step of flowing the liquid reagent into the flowing carrier gas for delivery of the liquid reagent into the chamber in a vaporized state comprises: flowing the liquid reagent into a vaporizer; within the vaporizer, using the flowing carrier gas to vaporize the liquid reagent that is flowed into the vaporizer; and supplying the vaporized liquid reagent to the chamber.
References Cited (Backward Citations)
US3708658A
Cited
US4439463A
Cited
US4517220A
Cited
US4542650A
Cited
US4671097A
Cited
US5250135A
Cited
US4989160A
Cited
EP0361171A1
Cited
US5114752A
Cited
WO1991019017A1
Cited
US5220515A
Cited
WO1992021789A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-05-28 | 1999-11-27 | 2000-05-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-05-28 | 2003-11-27 | 2004-05-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-05-28 | 2007-11-27 | 2008-05-28 | $7700.00 | Window Closed / Lapsed |