US4946241A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of manufacturing iron garnet layers
Assignee: US Philips Corp
•
Filing: 1989-07-25
•
Granted: 1990-08-07
•
Expires: 2009-07-25
Abstract
Abstract A method of manufacturing iron garnet layers on a substrate, in a layer sequence of different order by means of RF-cathode sputtering in an inert gas plasma, using a target comprising predominantly an iron garnet phase in addition to residual phases having a substantially equal sputtering rate, the ions of said inert gas plasma bombarding the growing layer having an ion energy of less than 10 2 eV and a pressure in the range from 0.1 to 2.0 Pa, in which method RF-power is fed into the target electrode (cathode) at a RF-voltage of approximately 200 V rms , thereby first depositing an amorphous to X-ray amorphous iron garnet layer as an intermediate layer at a substrate temperature below 460° C. and, subsequently, a polycrystalline iron garnet layer at a substrate temperature exceeding 520° C., while simultaneously applying a RF-voltage of approximately 50 V rms to the substrate electrode, which voltage is linearly reduced during the deposition of the first 5-10 nm of the layer to a floating potential relative to earth.
Inventors
- 👤 Jens-Peter Krumme
- 👤 John Petruzello
- 👤 Wolfgang Radtke
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 13:07
CPC Classifications
C; C23; C23C; C23C14/00; C23C14/06; C23C14/08; C30; C30B; C30B23/00; C30B23/02; C30B29/00; C30B29/10; C30B29/16; C30B29/22; C30B29/28
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
175 words
A method of manufacturing iron garnet layers on a substrate, in a layer sequence of different order by means of RF-cathode sputtering in an inert gas plasma, making use of a target electrode which comprises predominantly an iron garnet phase in addition to residual phases having an almost equal sputtering rate, the ions of said inert gas plasma bombarding the growing layer having an ion energy of less than 10 2 eV, and a pressure in the range from 0.1 to 2.0 Pa, wherein RF-power is first applied to the target electrode at a RF-voltage of approximately 200 V rms , thereby first depositing an amorphous iron garnet layer as an intermediate layer at a substrate temperature below 460° C. and, subsequently depositing a polycrystalline iron garnet layer at a substrate temperature exceeding 520° C., while simultaneously applying a RF-voltage of approximately 50 V rms to the substrate electrode, which voltage is linearly reduced during the deposition of the first 5-10 nm of the polycrystalline iron garnet layer to a floating potential relative to earth.
Claim 2
Independent Claim
175 words
A method of manufacturing iron garnet layers on a substrate, in a layer sequence of different order by means of RF-cathode sputtering in an inert gas plasma, making use of a target electrode which comprises predominantly an iron garnet phase in addition to residual phases having an almost equal sputtering rate, the ions of said inert gas plasma bombarding the growing layer having an ion energy of less than 10 2 eV, and a pressure in the range from 0.1 to 2.0 Pa, wherein RF-power is first applied to the target electrode at a RF-voltage of approximately 200 V rms , thereby first depositing an amorphous iron garnet layer as an intermediate layer at a substrate temperature below 460° C. and, subsequently depositing a polycrystalline iron garnet layer at a substrate temperature exceeding 520° C., while simultaneously applying a RF-voltage of approximately 50 V rms to the substrate electrode, which voltage is linearly reduced during the deposition of the first 5-10 nm of the polycrystalline iron garnet layer to a floating potential relative to earth.
Claim 3
Dependent Claim
22 words
A method as claimed in claim 1, wherein the amorphous intermediate layer is deposited in a thickness of up to 5 nm.
Claim 4
Dependent Claim
17 words
A method as claimed in claim 1, characterized in that argon is used as the inert gas.
Claim 5
Dependent Claim
28 words
A method as claimed in claim 1, wherein the pressure of the inert gas atmosphere is adjusted at a value in the range from 0.3 to 1.0 Pa.
Claim 6
Dependent Claim
18 words
A method as claimed in claim 4, wherein the pressure is adjusted at a value of 0.6 Pa.
Claim 7
Dependent Claim
70 words
A method as claimed in claim 1, wherein the iron garnet layers have a composition in accordance with the general formula (A, B) 3 (A, B) 5 O 12 , wherein A=at least one element selected from the group consisting of rare earth metals, Bi, Pb and/or Ca, and B=at least one element selected from the group consisting of Ga, Al, Fe, Co, Ni, Mn, Ru, Ir, In and/or Sc.
Claim 8
Dependent Claim
36 words
A method as claimed in claim 6, wherein the polycrystalline iron garnet layer has a composition in accordance with the formula Gd 2 ,11 Bi 1 ,01 Fe 4 ,06 Ga 0 ,82 O 12 .
Claim 9
Dependent Claim
36 words
A method as claimed in claim 6, wherein the amorphous iron garnet layer has a composition in accordance with the formula Gd 2 ,18 Bi 0 ,36 Fe 4 ,31 Ga 1 ,15 O 12 .
Claim 10
Dependent Claim
13 words
A method as claimed in claim 1, wherein a monocrystalline substrate is used.
Claim 11
Dependent Claim
20 words
A method as claimed in claim 9, wherein a monocrystalline disc of a semiconductor material is used as the substrate.
Claim 12
Dependent Claim
15 words
A method as claimed in claim 10, wherein a III-V-compound is used as the substrate.
Claim 13
Dependent Claim
15 words
A method as claimed in claim 11, wherein a substrate of gallium arsenide is used.
Claim 14
Dependent Claim
15 words
A method as claimed in claim 11, wherein a substrate of indium phosphide is used.
Claim 15
Dependent Claim
14 words
A method as claimed in claim 10, wherein a substrate of silicon is used.
Claim 16
Dependent Claim
13 words
A method as claimed in claim 1, wherein a non-monocrystalline substrate is used.
Claim 17
Dependent Claim
13 words
A method as claimed in claim 15, wherein a glass substrate is used.
Claim 18
Dependent Claim
27 words
A method as claimed in claim 1, wherein a magnetron is used as the target electrode, into which the RF-power required for the sputtering process is fed.
Claim 19
Dependent Claim
17 words
An optical waveguide comprising layers being manufactured in accordance with the method as claimed in claim 1.
Claim 20
Dependent Claim
17 words
An integrated optoelectronic component, comprising layers manufactured in accordance with the method as claimed in claim 1.
References Cited (Backward Citations)
US4608142A
Cited
US4832980A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-08-06 | 1994-02-05 | 1994-08-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-08-06 | 1998-02-05 | 1998-08-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-08-06 | 2002-02-05 | 2002-08-07 | $7700.00 | Window Closed / Lapsed |