US5894133A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sputter cathode for application of radioactive material
Assignee: Implant Sciences Corp
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Filing: 1996-12-18
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Granted: 1999-04-13
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Expires: 2016-12-18
Abstract
Abstract Making a sputter cathode for applying a radioactive material includes obtaining a wafer containing a base material having a stable precursor dissolved therein. The base material is transmutable into a material having a relatively short atomic half-life. The wafer is atomically activated to transmute a portion of the stable precursor into a radioactive material. The base material may be silicon or germanium. The stable precursor may be 31 P and the radioactive material may be 32 P. Atomically activating the wafer may include exposing the wafer to a source of thermal neutrons by, for example, placing the wafer in a high-flux nuclear reactor for approximately four weeks.
Inventors
- 👤 Anthony J. Armini
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 07:41
CPC Classifications
C; C23; C23C; C23C14/00; C23C14/22; C23C14/34; C23C14/3407; C23C14/3414
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
64 words
A method of causing an object to become radioactive, comprising the steps of: (a) obtaining a solid-state radioactive cathode containing a base material that is transmutable into a material having a relatively short atomic half-life and containing a radioactive material dissolved into the base material; (b) using the cathode as a source of radioactive atoms; and (c) accelerating the radioactive atoms toward the object.
Claim 2
Independent Claim
64 words
A method of causing an object to become radioactive, comprising the steps of: (a) obtaining a solid-state radioactive cathode containing a base material that is transmutable into a material having a relatively short atomic half-life and containing a radioactive material dissolved into the base material; (b) using the cathode as a source of radioactive atoms; and (c) accelerating the radioactive atoms toward the object.
Claim 3
Dependent Claim
31 words
A method according to claim 1, wherein the cathode further includes a surface coating material, substantially encapsulating the cathode and being transmutable into a material having a relatively short atomic half-life.
Claim 4
Dependent Claim
17 words
A method according to claim 2, wherein the surface coating material is less than 10 microns thick.
Claim 5
Dependent Claim
14 words
A method according to claim 2, wherein the coating material is the base material.
Claim 6
Dependent Claim
23 words
A method according to claim 4, wherein the base material and the coating material are silicon and the radioactive material is 32 P.
Claim 7
Dependent Claim
19 words
A method according to claim 1, wherein the base material is silicon and the radioactive material is 32 P.
Claim 8
Dependent Claim
25 words
A method according to claim 6, wherein the 32 P is embedded into the silicon at a depth of between one micron and 500 microns.
Claim 9
Dependent Claim
31 words
A method according to claim 1, wherein the base material is a wafer having a substantially circular shape, a diameter of approximately four inches, and a thickness of approximately 0.5 mm.
Claim 10
Dependent Claim
32 words
A method according to claim 1, wherein the base material is a wafer having a substantially square shape, an edge length of approximately 2 cm., and a thickness of approximately 0.5 mm.
Claim 11
Dependent Claim
28 words
A method according to claim 9, wherein accelerating the radioactive atoms toward the object includes using the cathode in a sputter-type ion source of an ion implantation device.
Claim 12
Dependent Claim
13 words
A method according to claim 1, wherein the object is a medical implant.
Claim 13
Dependent Claim
13 words
A method according to claim 11, wherein the object is an intra-arterial stent.
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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) | 2002-04-12 | 2002-10-12 | 2003-04-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-04-12 | 2006-10-12 | 2007-04-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-04-12 | 2010-10-12 | 2011-04-13 | $7700.00 | Window Closed / Lapsed |