Mass separator for ionized cluster beam

Claim 2

A process for selecting particles of a selected mass range from a cluster beam, comprising the steps of: ionizing the particles of the cluster beam to produce an ionized cluster beam; passing the ionized cluster beam through an electrostatic mass separator, the electrostatic mass separator including means for producing an electrostatic field that permits those particles having masses within the selected mass range to pass therethrough but repels particles having lesser masses, and extracting the particles of the selected mass range from the electrostatic mass separator.

Claim 3

The process of claim 1, wherein said step of ionizing utilizes a unipotential ionizer wherein all particles are ionized to the same potential level.

Claim 4

The process of claim 1, wherein the mass separator produces an angularly deflecting electrostatic field which deflects the motion of the particles in accordance with their masses.

Claim 5

Apparatus for producing a beam of ionized clusters, comprising: cluster source means for producing a cluster beam, the cluster beam having therein unclustered atoms and loosely bound clusters of atoms of from about 2 to about 10,000 atoms; ionizer means for receiving unclustered atoms and clusters from said cluster source means and for ionizing the unclustered atoms and clusters to produce an ionized beam; and first mass separator means for receiving the ionized beam, passing those clusters having a mass greater than a selected mass, and not passing the remainder of the cluster beam, said first mass separator means including means for creating an electrostatic field that retards the motion of ionized atoms and clusters in the ionized beam.

Claim 6

Apparatus for producing a beam of ionized clusters, comprising: cluster source means for producing a cluster beam, the cluster beam having therein unclustered atoms and loosely bound clusters of atoms of from about 2 to about 10,000 atoms; ionizer means for receiving unclustered atoms and clusters from said cluster source means and for ionizing the unclustered atoms and clusters to produce an ionized beam; and first mass separator means for receiving the ionized beam, passing those clusters having a mass greater than a selected mass, and not passing the remainder of the cluster beam, said first mass separator means including means for creating an electrostatic field that retards the motion of ionized atoms and clusters in the ionized beam.

Claim 7

The apparatus of claim 4, wherein said ionizer means includes unipotential ionizer means for ionizing atoms and clusters at a single potential level.

Claim 8

The apparatus of claim 4, wherein said mass separator means includes a retarding field electrode.

Claim 9

The apparatus of claim 4, wherein said mass separator means includes an electrode in the form of a grid.

Claim 10

The apparatus of claim 4, wherein said mass separator means includes an entrance electrode and a retarding field electrode.

Claim 11

The apparatus of claim 8, wherein each of said electrodes is in the form of a grid placed in the path of the cluster beam, the openings of the two grids being aligned.

Claim 12

The apparatus of claim 4, further including accelerating means for accelerating said ionized cluster beam.

Claim 13

The apparatus of claim 10, wherein said accelerating means is positioned to receive the ionized cluster beam after it passes through said mass separator means.

Claim 14

The apparatus of claim 4, further including second mass separator means for reflecting those clusters having a mass less than a second selected mass to pass into a target, said second mass separator means being positioned to receive the portion of the ionized cluster beam having masses greater than the selected mass, after it passes through said first mass separator means, so that said first mass separator means and said second mass separator means used in cooperation permit the selection of clusters of a narrow range of masses.

Claim 15

Apparatus for producing a beam of ionized clusters having masses greater than a selected mass, comprising: a cluster source that produces a cluster beam having therein unclustered atoms and loosely bound clusters of atoms of from 2 to about 10,000 atoms; an ionizer disposed so as to receive the cluster beam from said cluster source, said ionizer producing a beam of ionized atoms and clusters; and a first electrostatic mass separator disposed to receive the beam of ionized atoms and clusters from said ionizer, said first mass separator including a retarding field electrode in the form of a grid intercepting the beam of ionized atoms and clusters, so that, upon application of a sufficiently great electrical potential of the same sign as that of the ionization of the ionized cluster beam to said retarding field electrode, clusters of a mass greater than the selected mass pass through the grid to form a beam of ionized clusters having masses greater than the selected mass, and clusters of a mass less than the selected mass do not pass through the grid.

Claim 16

Apparatus for producing a beam of ionized clusters having masses greater than a selected mass, comprising: a cluster source that produces a cluster beam having therein unclustered atoms and loosely bound clusters of atoms of from 2 to about 10,000 atoms; an ionizer disposed so as to receive the cluster beam from said cluster source, said ionizer producing a beam of ionized atoms and clusters; and a first electrostatic mass separator disposed to receive the beam of ionized atoms and clusters from said ionizer, said first mass separator including a retarding field electrode in the form of a grid intercepting the beam of ionized atoms and clusters, so that, upon application of a sufficiently great electrical potential of the same sign as that of the ionization of the ionized cluster beam to said retarding field electrode, clusters of a mass greater than the selected mass pass through the grid to form a beam of ionized clusters having masses greater than the selected mass, and clusters of a mass less than the selected mass do not pass through the grid.

Claim 17

The apparatus of claim 13, wherein said mass separator further includes an entrance electrode in the form of a grid intercepting the cluster beam, the openings of the entrance electrode grid and the retarding field electrode grid being aligned.

Claim 18

The apparatus of claim 13, further including an accelerating means for accelerating the ionized cluster beam.

Claim 19

The apparatus of claim 13, wherein said accelerating means is positioned to receive the ionized cluster beam after it passes through said mass separator.

Claim 20

The apparatus of claim 13, further including a second electrostatic mass separator positioned to intercept the ionized cluster beam after it passes through said first electrostatic mass separator so as to generate a cluster beam with a narrow mass distribution.

Claim 21

The apparatus of claim 13, further including lens means for focusing the cluster beam, said lens means being positioned after said ionizer.

Claim 22

The apparatus of claim 13, further including deflection means for deflecting the cluster beam, said deflection means being positioned after said ionizer.