US4072767A
Expired / Lapsed
US
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Method for controlling chemical vapor deposition
Assignee: Hitachi Ltd
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Filing: 1976-06-07
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Granted: 1978-02-07
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Expires: 1996-06-07
Abstract
Abstract In forming a film of a purposive substance on a substrate by a chemical vapor deposition (CVD), the size of the film-forming substance particles formed in a reactor is detected as an electrical signal and flow rates of respective gases introduced into the reactor are controlled in response to this electrical signal. According to this control method, the fogging phenomenon owing to formation of the film-forming substance in the gas flow can be effectively prevented.
Inventors
- 👤 Kyo Suda
- 👤 Katsumi Takami
- 👤 Akira Shintani
- 👤 Shinobu Hase
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 02:07
CPC Classifications
C; C23; C23C; C23C16/00; C23C16/44; C23C16/52
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
92 words
In a process for chemical vapor deposition of particles of a film-forming substance on a substrate wherein the particles result from a reaction of gases of a gaseous mixture in a reactor, the improvement comprising measuring optically the particle size of particles of the film-forming substance formed in the reactor, converting the optically measured value to an electric signal, and controlling the flow rate of at least one gas of the gaseous mixture to be introduced into the reactor in response to the electric signal whereby a good quality film is produced.
Claim 2
Dependent Claim
92 words
In a process for chemical vapor deposition of particles of a film-forming substance on a substrate wherein the particles result from a reaction of gases of a gaseous mixture in a reactor, the improvement comprising measuring optically the particle size of particles of the film-forming substance formed in the reactor, converting the optically measured value to an electric signal, and controlling the flow rate of at least one gas of the gaseous mixture to be introduced into the reactor in response to the electric signal whereby a good quality film is produced.
Claim 3
Dependent Claim
37 words
A process according to claim 1, wherein the flow rate of at least one of the gases introduced in the reactor is controlled and the flow rates of the other gases are maintained at a constant level.
Claim 4
Dependent Claim
35 words
A process according to claim 1, wherein the flow rate of one of the gases introduced into the reactor is maintained at a constant level and the flow rates of the other gases are controlled.
Claim 5
Dependent Claim
25 words
A chemical vapor deposition control method according to claim 1 wherein the total flow rate of all the gases introduced into the reactor is controlled.
Claim 6
Dependent Claim
17 words
A process according to claim 4, wherein the total flow rate is controlled within a fixed range.
Claim 7
Dependent Claim
94 words
In a process for chemical vapor deposition of particles of a film-forming substance on a heated substrate wherein the particles result from a reaction of a reacting gas and a component of a mixed gas in a reactor, the improvement comprising measuring optically the size of particles of the film-forming substance formed in the reactor, converting the optically measured value to an electric signal, detecting the particle size as the electric signal and controlling the flow rate of at least one of the reacting gas and mixed gas in response to the electric signal.
Claim 8
Dependent Claim
94 words
In a process for chemical vapor deposition of particles of a film-forming substance on a heated substrate wherein the particles result from a reaction of a reacting gas and a component of a mixed gas in a reactor, the improvement comprising measuring optically the size of particles of the film-forming substance formed in the reactor, converting the optically measured value to an electric signal, detecting the particle size as the electric signal and controlling the flow rate of at least one of the reacting gas and mixed gas in response to the electric signal.
Claim 9
Dependent Claim
20 words
A process according to claim 6, wherein the total flow rate of the reacting gas and mixed gas is controlled.
Claim 10
Dependent Claim
17 words
A process according to claim 7, wherein the total flow rate is controlled within a fixed range.
Claim 11
Dependent Claim
104 words
A process according to claim 6, comprising measuring optically the size of the particles by withdrawing particles of the film-forming substance from the reactor for effecting chemical vapor deposition, passing the withdrawn film-forming substance particles through a light scattering cell in the form of an aerosol, directing a laser light beam through the light scattering cell wherein the particles of the film-forming substance cause scattering of the light beam, receiving light scattered by the particles from the light scattering cell, and generating a control signal in response to the received scattered light, which is a measure of the particle size distribution in the aerosol.
Claim 12
Dependent Claim
23 words
A process according to claim 6, wherein the reacting gas is oxygen and the mixed gas is a mixture containing nitrogen and silane.
Claim 13
Dependent Claim
33 words
A process according to claim 6, wherein the flow rate of the reacting gas is controlled and the flow rate of a component of the mixed gas is maintained at a constant level.
Claim 14
Dependent Claim
35 words
A process according to claim 6, wherein the flow rate of at least one component of the mixed gas is controlled and the flow rate of the reacting gas is maintained at a constant level.
Claim 15
Dependent Claim
105 words
In a process for forming a film of a substance on a substrate from a reacting gas of one of oxygen and ammonia and a multicomponent mixed gas containing nitrogen and silane by a chemical vapor deposition, the improved method for controlling the chemical vapor deposition which comprises measuring optically the size of particles of the film-forming substance formed in a reactor, converting the optically measured value to an electric signal, detecting the particle size as the electric signal and controlling the flow rate of at least one of the reacting gas and a component of the mixed gas in response to said electric signal.
Claim 16
Dependent Claim
105 words
In a process for forming a film of a substance on a substrate from a reacting gas of one of oxygen and ammonia and a multicomponent mixed gas containing nitrogen and silane by a chemical vapor deposition, the improved method for controlling the chemical vapor deposition which comprises measuring optically the size of particles of the film-forming substance formed in a reactor, converting the optically measured value to an electric signal, detecting the particle size as the electric signal and controlling the flow rate of at least one of the reacting gas and a component of the mixed gas in response to said electric signal.
Claim 17
Dependent Claim
23 words
A chemical vapor deposition control method according to claim 13, wherein the flow rate of one component of the mixed gas is controlled.
Claim 18
Dependent Claim
23 words
A chemical vapor deposition control method according to claim 13, wherein the flow rate of both components of the mixed gas is controlled.
Claim 19
Dependent Claim
20 words
A chemical vapor deposition control method according to claim 13, wherein the flow rate of the reacting gas is controlled.
Claim 20
Dependent Claim
45 words
A chemical vapor deposition control method according to claim 13, wherein the flow rate of one component of the mixed gas is maintained at a constant level and the flow rates of the reacting gas and the other component of the mixed gas ae controlled.
Claim 21
Dependent Claim
24 words
A chemical vapor deposition control method according to claim 13, wherein the total flow rate of the reacting gas and mixed gas is controlled.
Claim 22
Dependent Claim
21 words
A chemical vapor deposition control method according to claim 18, wherein the total flow rate is controlled within a fixed range.
Claim 23
Dependent Claim
17 words
A chemical vapor deposition control method according to claim 13, wherein the silane is diluted with argon.
Claim 24
Dependent Claim
24 words
A chemical vapor deposition control method according to claim 13, wherein the reacting gas is oxygen and the mixed gas contains nitrogen and silane.
Claim 25
Dependent Claim
17 words
A chemical vapor deposition control method according to claim 21, wherein the silane is diluted with argon.
Claim 26
Dependent Claim
17 words
A chemical vapor deposition control method according to claim 13, wherein the mixed gas further contains phosphine.
Claim 27
Dependent Claim
108 words
A chemical vapor deposition control method according to claim 13, comprising measuring optically the size of the particles by withdrawing particles of the film-forming substance from the reactor for effecting chemical vapor deposition, passing the withdrawn filmforming substance particles through a light scattering cell in the form of an aerosol, directing a laser light beam through the light scattering cell wherein the particles of the film-forming substance cause scattering of the light beam, receiving light scattered by the particles from the light scattering cell, and generating a control signal in response to the received scattered light, which is a measure of the particle size distribution in the aerosol.
Claim 28
Dependent Claim
17 words
A chemical vapor deposition control method according to claim 13, wherein the reactor is a belljar type.
References Cited (Backward Citations)
US3607378A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-02-06 | 1981-08-08 | 1982-02-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-02-06 | 1985-08-08 | 1986-02-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-02-06 | 1989-08-08 | 1990-02-07 | $7700.00 | Window Closed / Lapsed |