US4038158A
Expired / Lapsed
US
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Electrochemical generation of field desorption emitters
Assignee: EIDP Inc
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Filing: 1975-10-22
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Granted: 1977-07-26
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Expires: 1995-10-22
Abstract
Abstract An electrochemically generated field desorption emitter for use in mass spectrometry, and a process for forming such an emitter by immersing a metal support, as a first electrode, and a second electrode in an electrolytic liquid mixture having appropriate concentration of a metal compound, and applying a plurality of short duration, electrical pulses between the electrodes. The emitter so formed comprises an elongated metal support having a plurality of metal dendrites extending in a generally radially outwardly direction therefrom.
Inventors
- 👤 Maurice M. Bursey
- 👤 Deborah M. Hinton
- 👤 Martin C. Sammons
- 👤 R. Mark Wightman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 13:08
CPC Classifications
H; H01; H01J; H01J49/00; H01J49/02; H01J49/10; H01J49/16; Y; Y10; Y10S; Y10S204/00; Y10S204/09
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
109 words
A process for forming a field desorption emitter comprising a metal support and a plurality of metallic dendrites attached to and extending in a generally radially outwardly extending direction from said support, said process comprising the steps of: a. forming an electrolytic liquid mixture having an appropriate concentration of a compound of the metal from which the dendrites are to be formed; b. immersing said support, as a first electrode, in said mixture; c. immersing a second electrode in said mixture in electrodepositing association with said support; and d. applying a plurality of short duration pulses of electrical current with substantially zero current between said pulses across said electrodes.
Claim 2
Dependent Claim
109 words
A process for forming a field desorption emitter comprising a metal support and a plurality of metallic dendrites attached to and extending in a generally radially outwardly extending direction from said support, said process comprising the steps of: a. forming an electrolytic liquid mixture having an appropriate concentration of a compound of the metal from which the dendrites are to be formed; b. immersing said support, as a first electrode, in said mixture; c. immersing a second electrode in said mixture in electrodepositing association with said support; and d. applying a plurality of short duration pulses of electrical current with substantially zero current between said pulses across said electrodes.
Claim 3
Dependent Claim
21 words
The process of claim 1 further comprising the step of optimizing the temperature of said mixture while applying said electrical pulses.
Claim 4
Dependent Claim
20 words
The process of claim 1 wherein the step of forming an electrolytic liquid mixture comprises forming eutectic electrolytic liquid mixture.
Claim 5
Dependent Claim
19 words
The process of claim 1 wherein the step of forming an electrolytic liquid mixture comprises forming an electrolytic solution.
Claim 6
Dependent Claim
20 words
The process of claim 1 wherein the step of forming an electrolytic liquid mixture comprises forming an aqueous electrolytic solution.
Claim 7
Dependent Claim
40 words
The process of claim 1 wherein the step of forming an electrolytic liquid mixture comprises forming an aqueous solution of a compound containing a metal selected from the group consisting of nickel, cobalt, manganese, silver, rhenium, chromium, niobium and tantalum.
Claim 8
Dependent Claim
21 words
The process of claim 1 wherein the step of forming an electrolytic liquid mixture comprises forming an aqueous solution of nickel.
Claim 9
Dependent Claim
32 words
The process of claim 1 wherein the step of forming an electrolytic liquid mixture comprises forming a eutectic molten salt mixture containing a metal selected from the group of tungsten and molybdenum.
Claim 10
Dependent Claim
41 words
The process of claim 1 wherein the step of forming an electrolytic liquid mixture comprises forming an aqueous solution of a compound selected from the group consisting of silver nitrate, nickel chloride, nickel sulfate, nickel nitrate, manganese chloride, and manganese sulfate.
Claim 11
Dependent Claim
26 words
The process of claim 1 wherein said support is an elongated support, and the step of forming an electrolytic mixture comprises forming an aqueous electrolytic solution.
Claim 12
Dependent Claim
48 words
The process of claim 1 wherein said support is a tungsten wire and the process comprises the step of cleaning said support, prior to immersion in said mixture, by immersing said support in a solution containing nitric and hydrofluric acid, and then washing said support in distilled water.
Claim 13
Dependent Claim
41 words
The process of claim 1 wherein the step of applying a plurality of electrical pulses between said electrodes comprises applying at least two series of pulses, separated by a relaxation period during which no electrical pulses are applied between said electrodes.
Claim 14
Dependent Claim
30 words
The process of claim 1 wherein the step of applying a plurality of electrical pulses between said electrodes comprises applying pulses having a peak amplitude of at least 5 volts.
Claim 15
Dependent Claim
41 words
The process of claim 1 wherein the steps of applying a plurality of electrical pulses between said electrodes comprises first applying pulses having relatively low peak amplitude, allowing a relaxation period, and then applying pulses having a relatively high peak amplitude.
Claim 16
Dependent Claim
20 words
The process of claim 1 further comprising the step of cleaning said emitter to remove any residual electrolytic liquid mixture.
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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) | 1980-07-25 | 1981-01-24 | 1981-07-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-07-25 | 1985-01-24 | 1985-07-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-07-25 | 1989-01-24 | 1989-07-26 | $7700.00 | Window Closed / Lapsed |