Patent US5993555A successfully refreshed from Google Patents.
US5993555A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus and process for growing silicon epitaxial layer
Assignee: SEH America Inc
•
Filing: 1997-01-16
•
Granted: 1999-11-30
•
Expires: 2017-01-16
Abstract
Abstract An apparatus and a process for growing a silicon epitaxial layer on a main surface of a silicon substrate wafer are disclosed. The apparatus and process provide a reactor and a gas feeder system. The gas feeder system utilizes an auxiliary dopant supply mass flow control (MFC) to provide an auxiliary dopant only into a central injector that effects epitaxial deposition on the center of the wafer for autodoping correction. An auxiliary bellows metering valve is provided between the auxiliary MFC and the center injector to absorb pressure variations in the central flow line to prevent the pressure variations from reaching the auxiliary MFC. This results in a stable and consistent dopant concentration and resistivity profile.
Inventors
- 👤 Todd A. Hamilton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 07:26
CPC Classifications
C; C23; C23C; C23C16/00; C23C16/44; C23C16/455; C23C16/45561; C30; C30B; C30B25/00; C30B25/02; C30B25/14; C30B29/00; C30B29/02; C30B29/06; H; H10; H10P; H10P14/00; H10P14/20; H10P14/24; H10P14/29; H10P14/2901; H10P14/2902; H10P14/2905; H10P14/34; H10P14/3402; H10P14/3404; H10P14/3411
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
225 words
An apparatus for growing a silicon epitaxial layer on a main surface of a silicon substrate wafer, said apparatus having a horizontal chamber containing a susceptor mounted within the chamber for holding the silicon substrate wafer in a horizontal position on a top surface of the susceptor so that the main surface of the silicon substrate wafer is facing upward, said apparatus comprising: a series of injectors arranged transversely to a horizontal axis of the chamber, the injectors comprising a central injector passing a flow of a reactive gas past a central part of the chamber and peripheral injectors passing flows of the reactive gas past a peripheral part of the chamber, the reactive gas consisting of a silicon source, a dopant and hydrogen; a gas feeder system connected to the central injector and the peripheral injectors and feeding the reactive gas to the injectors; an auxiliary dopant feeder system connected to the central injector and passing flows of dopant gas past the central part of the chamber, wherein both the gas feeder system and the auxiliary dopant feeder system are connected to the central injector through a central flow line; and means connected between the auxiliary dopant feeder system and the central injector for absorbing pressure variations in the central flow line to prevent the pressure variations from reaching the auxiliary dopant feeder system.
Claim 2
Independent Claim
225 words
An apparatus for growing a silicon epitaxial layer on a main surface of a silicon substrate wafer, said apparatus having a horizontal chamber containing a susceptor mounted within the chamber for holding the silicon substrate wafer in a horizontal position on a top surface of the susceptor so that the main surface of the silicon substrate wafer is facing upward, said apparatus comprising: a series of injectors arranged transversely to a horizontal axis of the chamber, the injectors comprising a central injector passing a flow of a reactive gas past a central part of the chamber and peripheral injectors passing flows of the reactive gas past a peripheral part of the chamber, the reactive gas consisting of a silicon source, a dopant and hydrogen; a gas feeder system connected to the central injector and the peripheral injectors and feeding the reactive gas to the injectors; an auxiliary dopant feeder system connected to the central injector and passing flows of dopant gas past the central part of the chamber, wherein both the gas feeder system and the auxiliary dopant feeder system are connected to the central injector through a central flow line; and means connected between the auxiliary dopant feeder system and the central injector for absorbing pressure variations in the central flow line to prevent the pressure variations from reaching the auxiliary dopant feeder system.
Claim 3
Dependent Claim
16 words
The apparatus of claim 1, wherein said means for absorbing pressure is a bellows metering valve.
Claim 4
Dependent Claim
32 words
The apparatus of claim 1, wherein said reactive gas feeder system further comprises a controller controlling the mass flows of at least one of the silicon source, the dopant, and the hydrogen.
Claim 5
Dependent Claim
31 words
The apparatus of claim 1, further comprising means connected between the gas feeder system and the central injector for providing a predetermined amount of the reactive gas into the central injector.
Claim 6
Dependent Claim
22 words
The apparatus of claim 4, wherein said means for providing the predetermined amount of the reactive gas is a bellows metering valve.
Claim 7
Dependent Claim
13 words
The apparatus of claim 1, wherein said susceptor is a single wafer-processing type.
Claim 8
Independent Claim
206 words
An apparatus for growing a silicon epitaxial layer on a main surface of a silicon substrate wafer, said apparatus having a horizontal chamber containing a susceptor mounted within the chamber for holding the silicon substrate wafer in a horizontal position on a top surface of the susceptor so that said main surface of the silicon substrate wafer is facing upward, said apparatus comprising: a series of injectors arranged transversely to a horizontal axis of the chamber, the injectors comprising a central injector passing a flow of a reactive gas past a central part of the chamber and peripheral injectors passing flows of the reactive gas past a peripheral part of the chamber, the reactive gas consisting of a silicon source, a dopant and hydrogen; a gas feeder system connected to the central injector and the peripheral injectors and feeding the reactive gas to the injectors; a valve having a first end connecting to the gas feeder system and a second end connecting to the central injector for allowing a predetermined amount of the reactive gas into the central injector; and an auxiliary dopant feeder system connecting to the first end of said valve for passing flows of dopant gas past the central part of the chamber.
Claim 9
Independent Claim
206 words
An apparatus for growing a silicon epitaxial layer on a main surface of a silicon substrate wafer, said apparatus having a horizontal chamber containing a susceptor mounted within the chamber for holding the silicon substrate wafer in a horizontal position on a top surface of the susceptor so that said main surface of the silicon substrate wafer is facing upward, said apparatus comprising: a series of injectors arranged transversely to a horizontal axis of the chamber, the injectors comprising a central injector passing a flow of a reactive gas past a central part of the chamber and peripheral injectors passing flows of the reactive gas past a peripheral part of the chamber, the reactive gas consisting of a silicon source, a dopant and hydrogen; a gas feeder system connected to the central injector and the peripheral injectors and feeding the reactive gas to the injectors; a valve having a first end connecting to the gas feeder system and a second end connecting to the central injector for allowing a predetermined amount of the reactive gas into the central injector; and an auxiliary dopant feeder system connecting to the first end of said valve for passing flows of dopant gas past the central part of the chamber.
Claim 10
Dependent Claim
13 words
The apparatus of claim 7, wherein said valve is a bellows metering valve.
References Cited (Backward Citations)
US5487358A
Cited
US5421288A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2002-11-29 | 2003-05-31 | 2003-11-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-11-29 | 2007-05-31 | 2007-11-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-11-29 | 2011-05-31 | 2011-11-30 | $7700.00 | Window Closed / Lapsed |