US4937205A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Plasma doping process and apparatus therefor
Assignee: Panasonic Holdings Corp
•
Filing: 1988-08-04
•
Granted: 1990-06-26
•
Expires: 2008-08-04
Abstract
Abstract In a plasma doping process utilizing a radio frequency discharging in a vacuum by for doping an impurity into a semiconductor substrate, the radio frequency discharging is made intermittently and under controlling of average current of the discharging, thereby the impurity concentration is desirably controlled; and especially by selecting the vacuum in a range between 1×10 -4 -5×10 -2 torr, undesirable deposition of the impurity on the substrate surface is evadable.
Inventors
- 👤 Ichiro Nakayama
- 👤 Bunji Mizuno
- 👤 Masabumi Kubota
- 👤 Masuo Tanno
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 13:15
CPC Classifications
H; H10; H10P; H10P32/00; H10P32/10; H10P32/12; H10P32/1204
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
103 words
Method for plasma-doping of impurity on a semiconductor substrate comprising the steps of: placing an object semiconductor substrate on a first electrode in a vacuum chamber, introducing a gas of a controlled reduced pressure containing at least one impurity, into said vacuum chamber, impressing a radio frequency current of a high voltage in intermittence across said first electrode and a second electrode in said chamber thereby causing radio frequency discharging in said chamber, to generate plasma doping, and controlling a duty ratio of said intermittence in accordance with a program to control the amount of impurity doped on a surface of said substrate.
Claim 2
Dependent Claim
103 words
Method for plasma-doping of impurity on a semiconductor substrate comprising the steps of: placing an object semiconductor substrate on a first electrode in a vacuum chamber, introducing a gas of a controlled reduced pressure containing at least one impurity, into said vacuum chamber, impressing a radio frequency current of a high voltage in intermittence across said first electrode and a second electrode in said chamber thereby causing radio frequency discharging in said chamber, to generate plasma doping, and controlling a duty ratio of said intermittence in accordance with a program to control the amount of impurity doped on a surface of said substrate.
Claim 3
Dependent Claim
90 words
Method for plasma-doping of impurity on a semiconductor substrate comprising the step of: placing an object semiconductor substrate on a first electrode in a vacuum chamber, introducing a gas of a controlled reduced pressure containing at least one impurity into said vacuum chamber, and impressing a radio frequency current of a high voltage in intermittence across said first electrode and said second electrode in said chamber, the frequency of said intermittence being 0.1 Hz to 50 Hz, thereby causing radio frequency discharging in said chamber to generate a plasma doping.
Claim 4
Dependent Claim
90 words
Method for plasma-doping of impurity on a semiconductor substrate comprising the step of: placing an object semiconductor substrate on a first electrode in a vacuum chamber, introducing a gas of a controlled reduced pressure containing at least one impurity into said vacuum chamber, and impressing a radio frequency current of a high voltage in intermittence across said first electrode and said second electrode in said chamber, the frequency of said intermittence being 0.1 Hz to 50 Hz, thereby causing radio frequency discharging in said chamber to generate a plasma doping.
Claim 5
Dependent Claim
19 words
Method in accordance with claim 1, wherein said object substrate is on single-crystalline silicon, polycrystalline silicon or amorphous silicon.
Claim 6
Dependent Claim
15 words
Method in accordance with claim 1, wherein said impurity is boron, phosphorus or arsenide. PG,26
Claim 7
Dependent Claim
111 words
Method for plasma-doping of impurity on a semiconductor substrate comprising the steps of: placing an object semiconductor substrate on a first electrode in a vacuum chamber, introducing a gas of a controlled reduced pressure containing at least one impurity, into said vacuum chamber, impressing a radio frequency current of a high voltage across said first electrode and a second electrode in said chamber through means for measuring said radio frequency current, thereby causing radio frequency discharging in said chamber to generate a plasma, and controlling said radio frequency current based on a measurement thereof in accordance with a program, to control amount of impurity doped on the surface of said substrate.
Claim 8
Dependent Claim
111 words
Method for plasma-doping of impurity on a semiconductor substrate comprising the steps of: placing an object semiconductor substrate on a first electrode in a vacuum chamber, introducing a gas of a controlled reduced pressure containing at least one impurity, into said vacuum chamber, impressing a radio frequency current of a high voltage across said first electrode and a second electrode in said chamber through means for measuring said radio frequency current, thereby causing radio frequency discharging in said chamber to generate a plasma, and controlling said radio frequency current based on a measurement thereof in accordance with a program, to control amount of impurity doped on the surface of said substrate.
Claim 9
Dependent Claim
19 words
Method in accordance with claim 5, wherein said object substrate is on single-crystalline silicon, polycrystalline silicon or amorphous silicon.
Claim 10
Dependent Claim
14 words
Method in accordance with claim 5, wherein said impurity is boron, phosphorus or arsenide.
Claim 11
Dependent Claim
93 words
Method for plasma doping of impurity of a semiconductor substrate comprising the steps of: placing an object semiconductor substrate on a first electrode in a vacuum chamber, introducing a gas of a pressure of from 1×10 -3 torr to 5×10 -2 torr containing at least one impurity, into said vacuum chamber, intermittently impressing a radio frequency current of a high voltage across said first electrode and a second electrode in said chamber, and controlling the impressed period of said current to contol the amount of impurity doped on a surface of said substrate.
Claim 12
Dependent Claim
93 words
Method for plasma doping of impurity of a semiconductor substrate comprising the steps of: placing an object semiconductor substrate on a first electrode in a vacuum chamber, introducing a gas of a pressure of from 1×10 -3 torr to 5×10 -2 torr containing at least one impurity, into said vacuum chamber, intermittently impressing a radio frequency current of a high voltage across said first electrode and a second electrode in said chamber, and controlling the impressed period of said current to contol the amount of impurity doped on a surface of said substrate.
Claim 13
Dependent Claim
27 words
Method in accordance with claim 8, wherein the surface of the objective substrate is of single-crystalline silicon and have trenches as electrodes of capacitor or isolation region.
Claim 14
Dependent Claim
114 words
Method for plasma-doping of impurity on a semiconductor substrate comprising the steps of: placing an object semiconductor substrate on a first electrode in a vacuum chamber, introducing a gas of a pressure of from 1×10 -4 torr to 5×10 -2 torr containing at least one impurity, into said vacuum chamber, intermittently impressing a radio frequency current of a high voltage across said first electrode and a second electrode in said chamber and microwave into said chamber thereby causing radio frequency discharging and electronic cyclotron resonance discharge in said chamber, to generate plasma doping, and controlling the impressed period of said current to control the amount of impurity doped on a surface of said substrate.
Claim 15
Dependent Claim
114 words
Method for plasma-doping of impurity on a semiconductor substrate comprising the steps of: placing an object semiconductor substrate on a first electrode in a vacuum chamber, introducing a gas of a pressure of from 1×10 -4 torr to 5×10 -2 torr containing at least one impurity, into said vacuum chamber, intermittently impressing a radio frequency current of a high voltage across said first electrode and a second electrode in said chamber and microwave into said chamber thereby causing radio frequency discharging and electronic cyclotron resonance discharge in said chamber, to generate plasma doping, and controlling the impressed period of said current to control the amount of impurity doped on a surface of said substrate.
Claim 16
Dependent Claim
20 words
Method in accordance with claim 10, wherein said object semiconductor substrate is of single-crystalline silicon, polycrystalline silicon or amorphous silicon.
Claim 17
Dependent Claim
14 words
Method in accordance with claim 10, wherein said impurity is boron, phosphorus or arsenide.
Claim 18
Dependent Claim
27 words
Method in accordance with claim 10, wherein the surface of the objective substrate is of single-crystalline silicon and have trenches as electrodes of capacitor or isolation region.
Claim 19
Dependent Claim
93 words
Method for plasma-doping of impurity on a semiconductor substrate comprising the steps of: placing an object semiconductor substrate on a first electrode in a vacuum chamber. introducing a gas of a controlled reduced pressure containing at least one impurity, into said vacuum chamber, and impressing a radio frequency current of a high voltage in intermittence across said first electrode and a second electrode in said chamber thereby causing radio the frequency discharging in said chamber, frequency of said intermittence being changed to make plasma doping with depthwise modulated concentration in said semiconductor substrate.
Claim 20
Dependent Claim
93 words
Method for plasma-doping of impurity on a semiconductor substrate comprising the steps of: placing an object semiconductor substrate on a first electrode in a vacuum chamber. introducing a gas of a controlled reduced pressure containing at least one impurity, into said vacuum chamber, and impressing a radio frequency current of a high voltage in intermittence across said first electrode and a second electrode in said chamber thereby causing radio the frequency discharging in said chamber, frequency of said intermittence being changed to make plasma doping with depthwise modulated concentration in said semiconductor substrate.
References Cited (Backward Citations)
US4434036A
Cited
US4465529A
Cited
US4385946A
Cited
US4382099A
Cited
US4481229A
Cited
JPS5986214A
Cited
US4500563A
Cited
JPS59218728A
Cited
US4521441A
Cited
US4565588A
Cited
US4539217A
Cited
US4698104A
Cited
JPS62120041A
Cited
US4764394A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-06-25 | 1993-12-25 | 1994-06-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-06-25 | 1997-12-25 | 1998-06-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-06-25 | 2001-12-25 | 2002-06-26 | $7700.00 | Window Closed / Lapsed |