Amorphous magnetic thin films with highly stable easy axis

A sputtered thin film of noncrystalline amorphous magnetic material consisting of Fe, with between about 26 and 42 atomic percent Si, and from zero to ten percent of a transition metal selected from the group consisting of Cr, Mo, V, Ti, Cu, Pd, Pt, Re, Ru, Ta, Zr, Hf, Rh,, Y, and Al, said thin film having been annealed in an external magnetic field below the Curie Temperature and the crystallization temperature to stabilize the magnetic easy axis, said thin film possessing a low H.sub.c of about one Oersted and below for domains with magnetization in the plane, having a well defined easy axis in that the value of H.sub.k exceeds the value of H.sub.c and said stabilized magnetic easy axis remaining unchanged in direction in the absence of heating above the Curie point with a high permeability of above 1000 from DC to high frequencies on the order of 100 megahertz.

A sputtered thin film of noncrystalline amorphous magnetic material consisting of Co, B and from zero to ten percent of a transition metal selected from the group consisting of Cr, Mo, V, Ti, Cu, Pd, Pt, Re, Ru, Ta, Zr, Hf, Rh, Y, and Al, said thin film having been annealed in an external magnetic field below the Curie Temperature and the crystallization temperature to stabilize the magnetic easy axis, said thin film possessing a low H.sub.c of about one Oersted and below for domains with magnetization in the plane, having a well defined easy axis in that the value of H.sub.k exceeds the value of H.sub.c and said stabilized magnetic easy axis remaining unchanged in direction in the absence of heating above the Curie point with a high permeability of above 1000 from DC to high frequencies on the order of 100 megahertz.

A sputtered thin film of noncrystalline amorphous magnetic material consisting of Co, Fe, B and from zero to ten percent of a transition metal selected from the group consisting of Cr, Mo, V, Ti, Cu, Pd, Pt, Re, Ru, Ta, Zr, Hf, Rh, Y, and Al, said thin film having been annealed in an external magnetic field below the Curie Temperature and the crystallization temperature to stabilize the magnetic easy axis, said thin film possessing a low H.sub.c of about one Oersted and below for domains with magnetization in the plane, having a well defined easy axis in that the value of H.sub.k exceeds the value of H.sub.c and said stabilized magnetic easy axis remaining unchanged in direction in the absence of heating above the Curie point with a high permeability of above 1000 from DC to high frequencies on the order of 100 megahertz.

A sputtered thin film of noncrystalline amorphous magnetic material consisting of Fe, Si, B and from zero to ten percent of a transition metal selected from the group consisting of Cr, Mo, V, Ti, Cu, Pd, Pt, Re, Ru, Ta, Zr, Hf, Rh, Y, and Al, said thin film having been annealed in an external magnetic field below the Curie Temperature and the crystallization temperature to stabilize the magnetic easy axis, said thin film possessing a low H.sub.c of about one Oersted and below for domains with magnetization in the plane, having a well defined easy axis in that the value of H.sub.k exceeds the value of H.sub.c and said stabilized magnetic easy axis remaining unchanged in direction in the absence of heating above the Curie point with a high permeability of above 1000 from DC to high frequencies on the order of 100 megahertz.

A method of making amorphous magnetic thin films with a highly stable easy axis comprising depositing upon a surface of an object a thin film of an amorphous alloy consisting essentially of the composition represented by X Y where X is at least one element selected from the group consisting of Fe, Co and Ni and Y is at least one element selected from the group consisting of Si and B, and then annealing said thin film in an atmosphere of an inert gas and in an external magnetic field at a temperature below the Curie temperature and below the crystallization temperature for said alloy to stabilize the magnetic easy axis of said film for a period of time in excess of one hour sufficient to provide substantially increased stabilization of the magnetic anisotropy direction in the plane of the film.

A method of making amorphous magnetic thin films with a highly stable easy axis comprising depositing a thin film of an amorphous alloy consisting essentially of Fe and substantially 17 atomic percent B and then annealing said thin film in an atmosphere of an inert gas and in an external magnetic field at a temperature below the Curie temperature and below the crystallization temperature for said alloy and the maximum annealing temperature is on the order of 350.degree. C. and less than 400.degree. C. for consecutive annealing to stabilize the magnetic easy axis of said film for a period of time in excess of one hour sufficient to provide substantially increased stabilization of the magnetic anisotropy direction in the plane of the film.

A method of making amorphous magnetic thin films with a highly stable easy axis comprising depositing a thin film of an amorphous alloy consisting essentially of Fe and substantially 21-32 atomic percent B and then annealing said thin film in an atmosphere of an inert gas and in an external magnetic field at a temperature below the Curie temperature and below the crystallization temperature for said alloy and the annealing temperature is a maximum of about 400.degree. C. and less than 450.degree. C. for consecutive annealing at increasing temperatures to stabilize the magnetic easy axis of said film for a period of time in excess of one hour sufficient to provide substantially increased stabilization of the magnetic anisotropy direction in the plane of the film.

A method of making amorphous magnetic thin films with a highly stable easy axis comprising depositing a thin film of an amorphous alloy consisting essentially of Fe and and in the range of 37 atomic percent B and then annealing said thin film in an atmosphere of an inert gas and in an external magnetic field at a temperature below the Curie temperature and below the crystallization temperature for said alloy where the maximum annealing temperature is about 450.degree. C. for consecutive annealing at increasing temperatures to stabilize the magnetic easy axis of said film for a period of time in excess of one hour sufficient to provide substantially increased stabilization of the magnetic anisotropy direction in the plane of the film.

A method of making amorphous magnetic thin films with a highly stable easy axis comprising depositing a thin film of an amorphous alloy consisting essentially of Fe and on the order of 28 atomic percent Si annealed for a relatively short time and then annealing said thin film in an atmosphere of an inert gas and in an external magnetic field at a temperature in the range from 225.degree. C. to 275.degree. C. provided by consecutive annealing in increments below the Curie temperature and below the crystallization temperature for said alloy to stabilize the magnetic easy axis of said film for a period of time in excess of one hour sufficient to provide substantially increased stabilization of the magnetic anisotropy direction in the plane of the film.

A method of making amorphous magnetic thin films with a highly stable easy axis comprising depositing a thin film of an amorphous alloy consisting essentially of Fe and on the order of 33 atomic percent of Si said thin film annealed for about one hour in an atmosphere of an inert gas and in an external magnetic field at a temperature in the range of 200.degree.-225.degree. C. below the Curie temperature and below the crystallization temperature for said alloy to stabilize the magnetic easy axis of said film for a period of time in excess of one hour sufficient to provide substantially increased stabilization of the magnetic anisotropy direction in the plane of the film.

An amorphous magnetic thin film with a highly stable easy axis fabricated by sputtering a thin film of an amorphous alloy consisting essentially of Fe and on the order of 36 atomic percent of Si, said thin film annealed for about one-half hour at about 200.degree. C. and the equivalent time and temperature in an atmosphere of an inert gas and in an external magnetic field at a temperature below the Curie temperature and below the crystallization temperature for said alloy to stabilize the magnetic easy axis of said film for a period of time in excess of one hour sufficient to provide substantially increased stabilization of the magnetic anisotropy direction in the plane of the film.

An amorphous magnetic thin film with a highly stable easy axis fabricated by sputtering a thin film of an amorphous alloy consisting essentially of at least about 74 atomic percent of Co, about 5% of Fe, and about 14% of B said thin film annealed from 1 hour at 250.degree. C. and at temperatures and times comprising the equivalent in an atmosphere of an inert gas and in an external magnetic field below the Curie temperature and below the crystallization temperature for said alloy to stabilize the magnetic easy axis of said film for a period of time in excess of one hour sufficient to provide substantially increased stabilization of the magnetic anisotropy direction in the plane of the film.

An amorphous magnetic thin film with a highly stable easy axis fabricated by sputtering a thin film of an amorphous alloy consisting essentially of Fe, B, and at least about 5 to 17 atomic percent of Si with a ratio of about 3 Fe atoms per atom of B and then said thin film annealed in an atmosphere of an inert gas and in an external magnetic field at a temperature below the Curie temperature and below the crystallization temperature for said alloy to stabilize the magnetic easy axis of said film for a period of time in excess of one hour sufficient to provide substantially increased stabilization of the magnetic anisotropy direction in the plane of the film.