초록 ▼

A surface reaction process for controlled oxide growth is disclosed using a directed, low energy ion beam for compound or oxide formation. The technique is evaluated by fabricating Ni-oxide-Ni and Cr-oxide-Ni tunneling junctions, using directed oxygen ion beams with energies ranging from about 30 to

A surface reaction process for controlled oxide growth is disclosed using a directed, low energy ion beam for compound or oxide formation. The technique is evaluated by fabricating Ni-oxide-Ni and Cr-oxide-Ni tunneling junctions, using directed oxygen ion beams with energies ranging from about 30 to 180 eV. In one embodiment, high ion current densities are achieved at these low energies by replacing the conventional dual grid extraction system of the ion source with a single fine mesh grid. Junction resistance decreases with increasing ion energy, and oxidation time dependence shows a characteristic saturation, both consistent with a process of simultaneous oxidation and sputter etching, as in the conventional r.f. oxidation process. In contrast with r.f. oxidized junctions, however, ion beam oxidized junctions contain less contamination by backsputtering, and the quantitative nature of ion beam techniques allows greater control over the growth process.

대표청구항 ▼

A surface reaction process for compound formation on the surface of a sample material situated in a sample chamber, comprising: forming an ion plasma with an ion source having magnetic field producing means located around a plasma discharge chamber of said ion source, feeding a gas into said ion pla

A surface reaction process for compound formation on the surface of a sample material situated in a sample chamber, comprising: forming an ion plasma with an ion source having magnetic field producing means located around a plasma discharge chamber of said ion source, feeding a gas into said ion plasma which will form a solid compound product when ions of said gas react with said surface of said sample material, extracting said ions of said gas out of said ion plasma to form an ion beam, and applying a voltage potential to said ion source which will accelerate ions of said gas to a low energy in a directed beam which impinges onto said surface of said sample material to produce simultaneous sputter etching and compound formation on said surface, said voltage potential being used to determine the resulting compound thickness, wherein the rate of compound formation balances the rate of sputter etching at said resulting thickness.