Mass separator for ionized cluster beam

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.

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.