US3632405A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Crystals, in particular crystal whiskers and objects comprising such crystals
Assignee: US Philips Corp
•
Filing: 1969-04-14
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Granted: 1972-01-04
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Expires: 1989-04-14
Abstract
Abstract A method of manufacturing filamentary crystals, i.e., whiskers, and controlling the growth thereof in which a substrate on which are provided particles of a metal powder is heated so that the metal particles melt and form molten droplets while an atmosphere containing the substance forming the crystals is passed over the substrate. The substrate is dissolved in the metal droplets and precipitates growing a filament of whisker epitaxially. The thickness of the crystal is then controlled by adjusting the partial pressure of the metal in the atmosphere which controls the size of the droplets. In some cases, a separate source of metal for controlling the partial pressure of the metal in the atmosphere is provided.
Inventors
- 👤 Wilhelmus Franclsc Knippenberg
- 👤 Gerrit Verspul
- 👤 Johan Charles Marie Basart
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 04:34
CPC Classifications
C; C30; C30B; C30B11/00; C30B11/04; C30B11/08; C30B11/12; C01; C01B; C01B32/00; C01B32/90; C30B29/00; C30B29/10; C30B29/36; C01P; C01P2004/00; C01P2004/10; C01P2004/60; C01P2004/61
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
46 words
A method as claimed in claim 1, wherein obtaining crystals of constant thicknesses, the influence of the factors which may cause thickness variations during the crystal growth are compensated for by adjusting the size of the metal droplets by means of adjusting the said partial pressure.
Claim 2
Dependent Claim
34 words
A method as claimed in claim 1, wherein the size of the metal droplets is varied by varying the said partial pressure so as to obtain crystals having a previously determined variation in thickness.
Claim 3
Dependent Claim
46 words
A method as claimed in claim 1, wherein the partial metal pressure in the crystallization space is controlled by means of a separate source of the metal, the partial metal pressure in the crystallization space being adjusted by the temperature to which said source is exposed.
Claim 4
Dependent Claim
28 words
A method as claimed in claim 4, characterized in that the partial pressure of the metal is increased by increasing the temperature of the source of the metal.
Claim 5
Dependent Claim
35 words
A method as claimed in claim 4 wherein the crystallization is carried out in a gas current and the size of the metal droplets is controlled by controlling the rate of flow of the gas.
Claim 6
Dependent Claim
23 words
A method as claimed in claim 1 wherein the partial pressure of the metal is temporarily reduced by temporarily reducing the gas pressure.
Claim 7
Dependent Claim
41 words
A method as claimed in claim 6, wherein the partial pressure in the crystallization space is temporarily reduced by temporarily leading through a current of gas having a content of the metal which is lower than that in the crystallization atmosphere.
Claim 8
Dependent Claim
35 words
A method as claimed in claim 7, wherein a gas current is led through the crystallization space to which temporarily a substance is added which reacts with the metal forming a volatile compound of it.
Claim 9
Dependent Claim
39 words
A method as claimed in claim 1 wherein for manufacturing crystals with a metal coating, the partial pressure of the metal in the crystallization atmosphere is increased for a short period of time prior to terminating the crystallization growth.
Claim 10
Dependent Claim
27 words
A method as claimed in claim 4 in which the partial pressure of the metal is temporarily reduced by temporarily decreasing the temperature of the metal source.
References Cited (Backward Citations)
US3346414A
Cited
US3493431A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-01-03 | 1975-07-05 | 1976-01-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-03 | 1979-07-05 | 1980-01-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-03 | 1983-07-05 | 1984-01-04 | $7700.00 | Window Closed / Lapsed |