US 6,037,717 A · Cold-cathode ion source with a controlled position of ion beam

Abstract

A cold-cathode ion source with a closed-loop ion-emitting slit which is provided with means for generating a cyclically-variable, e.g., alternating or pulsating electric or magnetic field in an anode-cathode space. These means may be made in the form of an alternating-voltage generator which generates alternating voltage on one of the cathode parts that form the ion-emitting slit, whereas the other slit-forming part is grounded. The alternating voltage deviates the ion beam in the slit with the same frequency of the alternating voltage. In accordance with another embodiment, the aforementioned means may be an electromagnetic coil which generates a magnetic field which passes through the ion-emitting slit, thus acting on the condition of the spatial-charge formation and, hence, on concentration of ions in the ion beam. The cold-cathode ion source may be of any type, i.e., with the ion beam emitted in the direction perpendicular to the direction of drift of electrons in the ion-emitting slit or with the direction of emission of the beam which coincides with the direction of electron drift.

Claims28

Dependent claims

A method for controlling position of an ion beam on the surface of an object to be treated with said ion beam, comprising:

providing a cold-cathode ion source with crossed electrical and magnetic fields and with at least one ion-emitting slit, said ion source having a voltage source,
an anode connected to a positive potential of said voltage source;
and a
cathode which comprises at least two parts which are electrically isolated from each other and form said ion-emitting slit;
at least one of said two parts being connected to said voltage source;
activating said ion source and generating an ion beam which is emitted through said at least one ion-emitting slit toward said object, said ion beam being charged positively with respect to said at least one part of said cathode which is connected to said voltage source;
applying a potential to said at least one part of said cathode from said voltage source for generating an electric field across said at least one ion-emitting slit;
acting by said electric field onto said ion beam;
and
deviating said ion beam in a direction transverse to said direction of said ion beam.

7 more elements

An ion beam source with a closed-loop ion-emitting slit capable of emitting an ion beam toward an object located in a position reachable by said ion beam, comprising:

a hollow housing that functions as a cathode of said ion beam source;
anode located in said hollow housing and spaced from said cathode to form an ion acceleration and ionization space therebetween for ionization and acceleration of ions formed in said space during operation of said ion beam source;
magnetic field generating means in a magnetoconductive relationship with said anode and said cathode for forming a closed magnetoconductive circuit passing through said anode, said ionization gap, said cathode, and said magnetic field generating means;
said cathode having, on the side hollow housing facing said object, a first part and a second which are spaced from each other to form said closed-loop ion-emitting slit therebetween, said closed-loop ion-emitting slit being in the path of said magnetoconductive circuit;
electric power supply means for applying a positive charge to said anode;
means for generating a cyclically variable field acting on said ion beam on the path of emission of said beam from said ion source and capable of deviating said beam in the direction transverse to the direction of propagation of said beam with a frequency of said variable field;
and
means for the supply of a working medium into said hollow housing of said cathode to form an ion beam when said working medium passes through said acceleration and ionization gap.

5 more elements

Dependencies are inferred from the claim text.

Cold-cathode ion source with a controlled position of ion beam

Life of this patent

Cold-cathode ion source with a controlled position of ion beam

Life of this patent

Abstract

Claims28