Patent US4434036A successfully refreshed from Google Patents.
US4434036A
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Method and apparatus for doping semiconductor material
Assignee: Siemens AG
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Filing: 1982-05-03
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Granted: 1984-02-28
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Expires: 2002-05-03
Abstract
Abstract Method for doping semiconductor material, including a container into which doping material is led and aimed at the semiconductor material by means of an electrical field, which includes maintaining the doping material in a plasma in the container, and leading doping material ions into the semiconductor material by means of the electrical field, and an apparatus for carrying out the method.
Inventors
- 👤 Konstantin Hoerschelmann
- 👤 Helmold Kausche
- 👤 Werner Sp/a/ th
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 15:40
CPC Classifications
C; C30; C30B; C30B31/00; C30B31/06; C30B31/16; C30B31/20; C30B31/22; H; H10; H10P; H10P30/00; H10P30/20; H10P30/202; H10P30/204; H10P30/21; H10P30/28; H10P32/00; H10P32/10; H10P32/12; H10P32/1204
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
91 words
Method for doping semiconductor material, including a container into which doping material is led and aimed at the semiconductor material by means of an electrical field, which comprises placing a low-pressure plasma containing the doping material in a hydrogen-phosphine mixture in the container, maintaining the low-pressure plasma at a pressure of substantially 8×10 -4 torr, placing a high-frequency coil around the container, maintaining the frequency of the coil at substantially 4 MHz, and exciting the plasma to lead doping material ions into the semiconductor material by means of the electrical field.
Claim 2
Dependent Claim
91 words
Method for doping semiconductor material, including a container into which doping material is led and aimed at the semiconductor material by means of an electrical field, which comprises placing a low-pressure plasma containing the doping material in a hydrogen-phosphine mixture in the container, maintaining the low-pressure plasma at a pressure of substantially 8×10 -4 torr, placing a high-frequency coil around the container, maintaining the frequency of the coil at substantially 4 MHz, and exciting the plasma to lead doping material ions into the semiconductor material by means of the electrical field.
Claim 3
Dependent Claim
19 words
Method according to claim 1, which comprises providing the plasma in the form of a capacitively coupled-in high-frequency plasma.
Claim 4
Dependent Claim
19 words
Method according to claim 1, which comprises providing the plasma in the form of an inductively excited high-frequency plasma.
Claim 5
Dependent Claim
27 words
Method according to claim 3, which comprises separately controlling the electromagnetic field for plasma generation and for forming a strain voltage for accelerating ions onto a target.
Claim 6
Dependent Claim
52 words
Method according to claim 1, which comprises generating the plasma in the form of a capacitively excited high-frequency plasma in a doping gas, accelerating the doping material ions onto a target on which the semiconductor material to be doped is provided, and providing the semiconductor material in the form of semiconductor substrates.
Claim 7
Dependent Claim
52 words
Method according to claim 1, which comprises generating the plasma in the form of an inductively excited high-frequency plasma in a doping gas, accelerating the doping material ions onto a target on which the semiconductor material to be doped is provided, and providing the semiconductor material in the form of semiconductor substrates.
Claim 8
Dependent Claim
30 words
Method according to claim 5, which comprises providing the doping gas from the group consisting of PH 3 , B 2 H 6 and phosphoric vapor, from an evaporator source.
Claim 9
Dependent Claim
17 words
Method according to claim 3, which comprises providing the tank in the form of a glass receptacle.
Claim 10
Dependent Claim
31 words
Method according to claim 3, which comprises providing the tank in the form of a glass receptacle, and exciting the plasma in the form of a ring discharge with the coil.
Claim 11
Dependent Claim
24 words
Method according to claim 8, which comprises applying a strain voltage of substantially 500 volts between a target and an anode for several seconds.
Claim 12
Dependent Claim
20 words
Method according to claim 1, which comprises maintaining a current density on a target of substantially 1 mA/cm 2 .
Claim 13
Dependent Claim
24 words
Method according to claim 4, 5, 6 or 10, which comprises maintaining a current density on the target of substantially 1 mA/cm 2 .
Claim 14
Dependent Claim
31 words
Method according to claim 12, which comprises slowly upwardly controlling the strain voltage to reduce the maximal doping level in the semiconductor material and to obtain an optimal output doping profile.
Claim 15
Dependent Claim
27 words
Method according to claim 1, which comprises curing the semiconductor material at substantially 950° C. for substantially 30 minutes, and forming the desired doping profile by diffusion.
Claim 16
Dependent Claim
16 words
Method according to claim 1, which comprises curing the semiconductor material by bombardment with a laser.
Claim 17
Dependent Claim
17 words
Method according to claim 1, which comprises curing the semiconductor material by bombardment with an electron beam.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-02-27 | 1987-08-29 | 1988-02-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-02-27 | 1991-08-29 | 1992-02-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-02-27 | 1995-08-29 | 1996-02-28 | $7700.00 | Window Closed / Lapsed |