KR20010050049A - Low permeability non-planar ferromagnetic sputter targets - Google Patents

Abstract

PURPOSE: To provide a non-planar sputtering target for magnetron cathode sputtering of magnetic thin film, capable of eliminating waste of expensive ferromagnetic material, reducing the frequency of replacement of target, and causing no deposition of foreign particles, by reducing the magnetic permeability of at least part of the ferromagnetic material to a value lower than the intrinsic magnetic permeability of the material. CONSTITUTION: The reduction in magnetic permeability can be attained by bending the ferromagnetic material in the part of targets 10 and 100 where most of sputtering occurs. By the reduction in magnetic permeability, considerable increases in leakage flux 26 and 126 at the target surface 38 and 138 are brought about and argon pressure reduction necessary to obtain stable plasma takes place. The reduction in magnetic permeability makes possible the increase of target thickness, which results in the prolongation of target life and reduction in the frequency of target replacement. Because of the absence of machining and target gap, waste of material can be eliminated and deposition of foreign particles can be prevented.

Description

Low permeability non-planar ferromagnetic sputter targets

The present invention relates to a ferromagnetic non-planar sputter target for improving target performance by having a low magnetic permeability, and a method of manufacturing the same.

Sputter targets made of ferromagnetic materials are critical for thin film deposition in industries such as data storage and ultra high density integrated circuits (VLSI). Sputtering of the electron cathode is one means of sputtering magnetic thin films.

The negative electrode sputtering method includes ion bombardment of a target containing ferromagnetic material. The ferromagnetic target forms part of the cathode assembly in a vacuum chamber containing an inert gas such as argon. An electric field is applied between the cathode assembly and the anode in the chamber, and the gas is ionized by collision with electrons emitted from the surface of the cathode and forms a plasma between the target surface and the substrate. Positive gas ions are attracted to the cathode surface, and particles of material are removed as the ions hit the target and then traverse the closure, to a substrate or substrates located on a support held at or near the anode potential. It is deposited as a thin film.

Although the sputtering method can be performed solely on the electric field, essentially increased deposition rates are possible by cathodic sputtering of the macronet, where an arcuate magnetic field formed in a closed loop on the sputter target surface is produced by the electric field. Nested in The magnetic field of the arcuate closed loop traps electrons in an annular region adjacent to the surface of the target, thereby splitting the collision between electrons and gas atoms to produce a corresponding increase in ion water in the region. The magnetic field is typically generated by positioning one or more magnets behind the target. This causes a magnetic field leakage on the surface of the target so that the plasma density can be increased.

Particle erosion from the sputter target surface occurs in a very narrow ring region corresponding to the magnetic field shape of the closed loop. Only part of the entire target material in the erosion groove, ie the so-called "race track", is consumed before the target must be replaceable. These results typically only use 18-25% of the target material. Thus, in general, a very expensive amount of material must be consumed or recycled. In addition, a significant amount of "stop time" of deposition apparatus arises due to the need for frequent target replacement.

In order to solve this drawback of the magnetron sputtering method, various possible solutions have been sought. One potential solution is to increase the thickness of the target. If the target is very thick, sputtering can be handled for a very long time before the race track area is consumed. However, ferromagnetic materials exhibit difficulties that do not occur in non-ferromagnetic materials. For macronet sputtering, the leakage magnetic field at the magnetic leakage flux (MLF) or the target sputter surface must be high enough to start and support the plasma. In typical sputtering conditions, such as an argon pressure of 5-10 mTorr, the maximum MLF is approximately 150 gauss, preferably about 200 gauss for high speed sputtering. For a typical stuttering state, a magnetic strength of at least about 1000 gauss is required. The magnetic strength of the partially negative cathode determines the MLF. The higher the magnetic strength is, the higher the MLF is. However, in the case of ferromagnetic sputter targets, the high intrinsic magnetic permeability of the material shields the magnetic field from the magnets behind the target, thus reducing the MLF at the target surface.

For air and nonferromagnetic materials, the magnetic permeability is very close to 1.0. As used herein, ferromagnetic material refers to a material whose intrinsic magnetic permeability is greater than 1.0. Magnetic permeability refers to the reaction (magnetization) of a material under magnetic field. In the CGS unit, this is

Permeability = 1 + 4π (M / H) is defined.

Here, M represents magnetization and H represents magnetic field. For sputter targets currently available, the permeability range is from 1.0 to 100 or more. The value depends on the particular material and method of preparation. For example, the processed Co sputter target has a permeability of about 10 or less, while the processed NiFe and Fe sputter targets have a permeability greater than 20.

Due to the high permeability and low MLF, ferromagnetic sputter targets are generally made thinner than nonmagnetic sputter targets to ensure that sufficient magnetic fields are leaked to maintain the plasma required for Macnetron sputtering. Non-ferromagnetic targets are typically 0.25 inches or more, while ferromagnetic targets are generally 0.25 inches or less. For some ferromagnetic materials, especially at high magnetic permeability, the target must be processed to less than 0.0625 inches to achieve an MLF of 150 gauss, and some very high magnetic permeability materials can simply achieve an MLF of 150 gauss. It is impossible to sputter the magnetron because there is no. Thus, these ferromagnetic targets cannot simply be thickened to reduce the downtime of the device, but they must be made substantially thinner. In order to increase the thickness, the MLF must be increased to some extent;

U. S. Patent No. 4,401, 546 describes a planar ferromagnetic target that achieves a thickness of 0.20 inch (5 mm) by a segmented target, wherein the segment has a magnetic field leakage to produce 200 gauss of MLF at the surface of the target. Separated by gaps. This is an improvement over conventional ferromagnetic targets that can be processed no thicker than 0.055 inches (1.4 mm), preferably 0.028 inches (0.7 mm) to generate 200 gauss of MLF.

US Pat. No. 4,412,907, in the embodiment of FIG. 4, is one inch thick with each segment having an inclined portion such that the magnetic field produces an angular gap that leaks to produce more than 730 gauss of MLF at the surface of the target. (25 mm) or more segmented planar ferromagnetic targets are described.

U. S. Patent No. 5,827, 414 also describes a planar ferromagnetic target to achieve a thickness of 0.16-1.0 inch (4-25 mm) by the gap in the target. In this configuration, the gap is a radial gap formed by the slots of the target body perpendicular to the flux of the magnetron, so that the sputtering plasma density is parallel to the body surface of the target and more effective and uniform leakage to the magnetic field. Generates.

The method of assembling the target from each segment and processing the slots with the target body to increase the MLF is not preferred because it allows the target to be thicker, but the gap allows deposition and sputtering of debris from the backing plate. . Foreign matter in the thin film sacrifices the density of the target. In addition, this method of increasing the target thickness does nothing to increase the amount of target material consumed.

Another way to solve the above problem is to remove the target portion outside of the race track area or to change the design of the target to increase the efficiency of erosion in the race track area. In some applications the initial sputtering from the surface of the target that is completely flat tends to be nonuniform because of the influence of the arcuate closed magnetic field. As sputtering spreads, eroded valleys form on the target surface in the region of the closed loop magnetic field. The deposition of sputtered material from the target becomes more uniform when the valley shape becomes stable. Thus, non-planar targets with preformed notches, grooves or curvatures machined into the race track area can be used to obtain uniform sputtering from the start. Plate- or cup-shaped targets are particularly useful for a variety of reasons, since the curvature is designed to correspond to the valleys in which the curvature can naturally form, and unnecessary material in the center of the race track area is removed prior to sputtering. to be. These non-planar target shapes reduce target material consumption, increase efficiency, and increase the uniformity of the deposited film, but they do nothing to increase the target thickness of the ferromagnetic target to reduce the time needed for target replacement. Do not. In addition, such a non-planar target is usually formed into a circular or circular target blank by being processed in a shelf or the like. Processing is simply a method of material removal, resulting in unnecessary amounts of material being consumed prior to magnetron sputtering.

In general, the higher the permeability of the ferromagnetic material, the thinner the thickness of the sputter target is required. However, this limitation of target thickness shortens the life of the target, wastes material, and requires more frequent replacement of the target. In addition, the high permeability and low MLF of the ferromagnetic target results in high impedance, low deposition rate, narrow erosion grooves, poor film uniformity and poor film performance. Thus, it is desirable to provide a low permeability, high MLF, non-planar ferromagnetic sputter target that can be made very thick without sacrificing the density of the film.

1 is a side view, shown in cross section, of a non-planar target of the present invention having a right angle shape;

2 is a cross-sectional view of a non-planar tatt of the present invention having a bent shape.

* Description of the symbols for the main parts of the drawings *

10 target 12: bottom

14: side wall portion 16: angled region

18: deformation portion 26: magnetic flux line

38: sputter surface 42: target particles

The present invention provides a non-planar ferromagnetic sputter target for use in magnetron cathode sputtering of magnetic thin films, wherein the ferromagnetic material has a lower magnetic permeability than the intrinsic magnetic permeability of the material in at least a portion of the target. For this purpose, according to the principles of the present invention, the non-planar shape comprises cobalt, nickel, iron or an alloy thereof by means of a deformation technique which basically bends the material in at least one part of the target where most sputtering takes place. It is formed from a solid, single target blank. By this deformation method, the intrinsic magnetic permeability of the material of at least 1.0 is lowered such that an increase in leakage of the magnetic field can occur at least in the deformed region. Thus, the ferromagnetic sputter target can start and maintain a plasma for magnetron sputtering.

An additional feature of the present invention is the ability to achieve a sufficiently high magnetic leakage flux to start and maintain the plasma while increasing the thickness of the non-planar target, with larger thicknesses increasing the lifetime of the target and reducing the frequency of target changes. . Ferromagnetic targets of any ferromagnetic material can be made in accordance with the principles of the present invention with a thickness of at least 0.05 inches to produce a minimum MLF of about 150 gauss. Also, the impedance of the target material is reduced, so that lower argon pressure can be used to obtain a stable plasma in which it can be maintained through the sputtering method.

These and other objects and advantages of the invention will be better understood from the accompanying drawings and the description of the invention.

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention, which illustrate the general description of the invention and the principles of the invention described above and are described in detail below.

The present invention provides a low permeability nonplanar ferromagnetic sputter target. The low permeability is achieved by providing a modification method as described herein. The low magnetic permeability of the ferromagnetic material used for the sputter targets of the present invention results in a large increase in MLF at the surface of the ferromagnetic target and lowers the argon pressure needed to obtain a stable plasma. In addition, the low permeability of the ferromagnetic material allows for an increase in target thickness, which results in longer target life and reduces the frequency of target replacement. The low transmittance allows for a high deposition rate at the same or lower magnetron magnetic field, which contributes to improved film magnetic properties and improves film uniformity. In addition, low permeability results in wider sputter erosion grooves or areas, so the availability of higher targets becomes very important in reducing the consumption for targets made of expensive materials.

Ferromagnetic materials according to the present invention include, but are not limited to, for example:

That is, a) pure Co and Co based alloys such as CoCr, CoCrPt, CoCrTa, CoNiCr, CoCrPtTa, CoCrPtTaNb, CoCrPtTaB, CoCrPtTaMo used for magnetic recording media, and CoFe, CoNiFe, CoNb, CoNbZr, CoTaZr, CoZrCr.

b) alloys of pure Ni and Ni bases such as NiFe and NiFeCo.

c) alloys of pure Fe and Fe bases, such as FeTa, FeCo and FeNi.

d) other binary, tertiary, quaternary and higher alloys including Ni, Fe, Co and other elements with inherent magnetic permeability greater than 1.0.

In accordance with the principles of the present invention, the ferromagnetic material is formed into a non-planar single sputter target shape by deformation as described herein. By nonplanar, as used herein, is meant to include any sputter target having a non-planar shape, such as the shape of a concave dish, wherein sputtering occurs at or near the area of the target where the sputtering is bent or angled. . Such non-planar shapes have proven to have numerous advantages in planar shapes for some applications.

The ferromagnetic target according to the invention is provided by deforming the target blank only in or in the region where sputtering occurs, so that the permeability of the ferromagnetic material is lowered from its intrinsic value in the deformed region. And, "low permeability" ferromagnetic materials, as used herein, include materials with an intrinsic magnetic permeability of greater than 1.0 and deformed regions with magnetic permeability greater than 1.0 but less than the intrinsic magnetic permeability of the material. Branch refers to the sputter target. In particular, the bent or angled areas of the non-planar targets are formed by deformation in the race track area (as opposed to material removed by processing). Deformation In particular, stresses and strains generated in the material by bending of the material by the deformation method reduce the permeability of the ferromagnetic material in the deformed region. Without being determined by theory, the stresses and strains generated in the material change the magnetic energy of the material and alter the permeability alternately. Thus, the non-planar target will have at least very low permeability in the bent or angled portions of the target that are in the race track area where sputtering occurs. The high permeability in the ferromagnetic target blocks or shields the magnetic field from the magnet, and a decrease in the permeability of the target material in the deformed region causes the magnetic field to leak through the target material, which is at the target surface to maintain the plasma. Generate a higher MLF. If desired, the entire target may be deformed, which will result in reduced permeability through the target material rather than directly in the sputtering region. This will increase the MLF at the surface of the tonic target.

For example, a NiFe target blank processed by a conventional method, which is by no means limiting, exhibits a uniform permeability of 20.5. The permeability of the same NiFe target modified in accordance with the principles of the present invention represents a magnetic permeability of 19 in the modified region. At a thickness of 0.110 inches, a magnetic strength of 1,000 gauss, and an argon pressure of about 5-10 mTorr, the conventional NiFe sputter target has MLF at a sputtering surface of about 3000 gauss, whereas the two 0.110 inches of the present invention. NiFe targets have MLF at sputtering surfaces of 380 gauss and 350 gauss, respectively.

The deformation technique of the present invention includes any deformation method that generates a stress, strain or other microstructure or physical change in the material to produce a uniform or local change in magnetic pitch. Bending, compressing, stretching or other deforming action may also affect all or part of the target blank material. Without limiting the scope of the present invention, for example, the deformation technique may be any spinning, press deformation, roll forming, deep or shallow drawing, deep extrusion, stamping, punching. Drop hammer forming, and explosive forming. Among these techniques, spinning, press molding, dip extrusion and drop hamber molding provide the best results and / or provide the most effective and economical method. For flexural deformation techniques of the material, a good change of about 10 ° or more generates sufficient stress and / or strain to change the permeability.

The spinning technique forms the target blank into a seamless hollow cylinder, or other circular shape, with or without a bottom by a combination of rotation and force. Generally, a bent or angled sputter target is formed at the bottom of the end face.

The press forming technique produces a non-planar target shaped to be designed to match the die and ram by applying pressure to the press ram to force and deform the target blank with a press die. During this deformation method, the speed and holding pressure of the ram can be controlled in close proximity.

The roll forming technique uses three or more rolls to deform the target blank into a non-planar shape with a seam. The technique of roll forming involves bending the material as opposed to other rolling methods that use two opposed rolls that simply reduce the thickness of the material. However, the seam may cause nonuniformity in the deposited film.

The deep and shallow drawing technique uses an opposite edged punch or die (drawing ring) that deforms the target blank to produce a cup, cone or similar shape.

The deep extrusion technique involves the displacement of the ferromagnetic material by plastic flow under non-uniform but uniform pressure. The relative motion of the punch and die causes the ferromagnetic material to flow in the required direction. The ferromagnetic materials harden when deformed at temperatures below their recrystallization temperature.

Stamping techniques form a shallow print in the target blank by compression between a punch and a die. Uniform thickness in all areas of the target is generally maintained, but some stretching may occur.

The punching technique is similar to the stamping and pressing method. During this deformation, the shape or contour of the target is controlled by matching the die sections.

Drop hammer forming technology deforms the target blank by a sudden impact from which a high proportion of strain energy is released from the drop hammer. The hammer described above depends on the gravity of its force.

The explosion shaping technique molds the target blank by the immediate high pressure generated from the explosion of the explosive. Such explosive action may occur in a system that is limited or unbounded.

By reducing the permeability of the ferromagnetic material and thus increasing the MLF at the surface of the target, the ferromagnetic target of the present invention can be made thicker than conventionally processed ferromagnetic targets. Magnetic fields that are no longer shielded by high permeability can leak through the thicker target material. Since the target of the present invention can also be formed in a single piece, no foreign matter is introduced into the deposited film due to the target gap.

The specific thickness and shape of the target of the present invention may vary depending on the user and the ferromagnetic material used. In general, any shape and material target can be made thick if modified according to the principles of the present invention. Cobalt and its alloys have a fundamentally lower permeability than nickel and iron, so that larger thicknesses will be obtained with a target of cobalt base, with or without the modification technique of the present invention as compared to targets of nickel and iron bases. The present invention is particularly advantageous for the production of targets of nickel base and iron base, and the magnetic permeability of the material starting here is so high that MLF of 150 gauss cannot be previously achieved, so that magnetron sputtering cannot be used, or such The target must be processed to a very thin size to allow sufficient leakage of the magnetic field. Such materials can be formed with very thick targets that can leak sufficient magnetic fields to maintain and start plasma with the same magnetron field strength, even at higher amounts to increase the deposition rate.

For example, but not by way of limitation, FIG. 1 includes an annular bottom 12, sidewall portions 14 and an angled region 16 between the bottom and sidewall portions to form a single shape of the seamless. A cross-sectional right angle dish-shaped target 10 (shown inverted in use) is shown in cross section. The target 10 is formed from a circular target blank (not shown) by a deformation technique such as spinning, where most of the deformation finally comprises an angled region 16 and a sidewall 14. Applied to part 18 of. Thus, the magnetic permeability of the material is contiguous with the decrease of the permeability less propagating in the direction towards the center 22 of the bottom 12 and is the lowest at the deformation 18. As shown by the magnetic flux line 26, most leakage of the magnetic field occurs from a magnet (not shown) behind the target 10 in the deformed region 18 where the magnetic permeability is lowest. . As shown by the phantom line, the deformed region 18 comprises the region in which the erosion region or groove 30 forms the so-called race track region of the target specifically designed. Thus, a dense plasma 34 is held adjacent to the race track area, where gas ions continuously strike the sputter surface 38 and release target particles 42, and then the target material passes through It is deposited on the substrate 46 as a magnetic thin film until it is sputtered.

In a further embodiment, FIG. 2 shows, in cross section, another embodiment of the invention of a bent dish-shaped target 100 (shown in an inverted use position) mounted to a support backing tray 110, wherein The target 100 has a bottom 112, a sidewall 114, and a bent region 116 between the bottom and the sidewall to form a single shape of the seam. The deformation is applied to the portion 118 of the material that finally includes the bent region 116 and the sidewalls 114. In addition, as shown by the magnetic flux line 126, most leakage of the magnetic field occurs in the strained region 118. Thus, the dense plasma 134 is obtained in an area adjacent to where the erosion groove 130 shown in phantom is formed, so that the target particles 142 are continuously removed from the sputter surface 138, and the magnetic It is deposited on the substrate 146 as a thin film.

The low permeability targets of the present invention allow for higher rates of deposition with the same or lower magnetron field strength. High rates of deposition help in many cases to improve the magnetic properties of the film. In addition, low permeability results in more uniform film thicknesses, wider sputter erosion grooves, and higher target availability. Thus, the target of the present invention reduces the replacement period of the target, reduces the consumption of the target material, and also provides a uniform and high purity magnetic thin film.

An additional advantage of the present invention is that the increase in MLF of the target is a corresponding decrease in sputtering impedance, which reduces the minimum argon pressure needed to obtain a stable plasma. High impedance causes plasma ashing which makes the plasma unstable, making the target more difficult to sputter. By reducing the impedance of the target of the present invention, a stable plasma can be obtained, and a low minimum argon pressure can be maintained through the sputtering method.

To demonstrate the effect of the present invention, two NiFe sputter targets with ashtray shape and 0.110 inch thickness are sputtered in the subnormal state by magnetron cathode sputtering. The cathode comprises a standard S-gun magnet having a plasma formed near the corner of the inner ashtray shaped ring. Standard S-gun magnets, such as those sold by Sputter Film Incorporated in Santa Barbara, California, have a magnetic strength of only about 400 gauss and are typically used to sputter nonferromagnetic materials such as aluminum. The standard S-gun magnet generates weaker magnetic flux at the corners of the magnet and the target surface. The minimum argon pressure required to obtain a stable plasma and the magnetic flux at the surface of the target are shown in Table 1 for conventional uniform permeability targets and the target of the present invention.

Magnetic flux Minimum Ar Pressure (mTorr) Conventional NiFe Targets 37 20 Enhanced NiFe Target 61 16 Improving % 65% 20%

The smaller argon pressure is required to obtain a stable plasma for the improved NiFe target of the present invention for targets of the same thickness and shape. In achieving and maintaining the stable plasma, higher MLF is generated at the surface of the target of the present invention than 65% more than the surface of the conventional target.

In order to achieve an MLF of at least about 150 gauss, the ferromagnetic target must be sputtered under uniform conditions. In order to achieve a normal state, a small intensity of at least 1000 gauss is typically required, although it can be made smaller for ferromagnetic targets, or very thin targets, with regions of low permeability close to 1.0. An example of a strength magnet of about 1000 gauss that can be used in accordance with the principles of the present invention is a model RMX-34 magnet sold from Orangeburg Materials Research Corporation, New York. In addition, higher strength magnets can be used in accordance with the principles of the present invention for higher MLF readings or larger target weights, such as 2000-3000 gauss model SYM-4B magnets sold from Sony Corporation, Tokyo, Japan. Using high intensity magnets designed for ferromagnetic targets and argon pressures of only 5-10 mTorr or less is necessary to achieve and maintain a stable plasma.

The present invention provides a non-planar ferromagnetic sputter target for use in magnetron cathode sputtering of magnetic thin films, wherein the ferromagnetic material has a lower magnetic permeability than the intrinsic magnetic permeability of the material in at least a portion of the target. By this deformation method, the intrinsic magnetic permeability of the material of at least 1.0 is lowered such that an increase in leakage of the magnetic field can occur at least in the deformed region. Thus, the ferromagnetic sputter target can start and maintain a plasma for magnetron sputtering.

Then, a sufficiently high magnetic leakage flux is achieved to start and maintain the plasma while increasing the thickness of the non-planar target, with the larger thickness increasing the lifetime of the target and decreasing the frequency of target change. Also, the impedance of the target material is reduced, so that lower argon pressure can be used to obtain a stable plasma in which it can be maintained through the sputtering method.

Although the invention has been described by way of explanation of its embodiments, these embodiments have been described in great detail, they do not limit or limit the scope of the appended claims for the description. Additional advantages and modifications can be readily made by those skilled in the art. For example, although some modification techniques have been described herein, other techniques can be used in accordance with the principles of the present invention as long as they can reduce the magnetic permeability of the material in the modified region of the target. Thus, the invention in its broader aspects is not intended to limit the specific details, representative apparatus and methods and embodiments shown and described. Accordingly, it may be made from the above detailed description without departing from the spirit and scope of the applicant's general inventive concept.

Claims (10)

A method for producing a low permeability, non-planar ferromagnetic sputter target for use in magnetron cathode sputtering, Forming a target blank from a ferromagnetic material having an intrinsic magnetic permeability greater than 1.0; Deforming the target blank into a non-planar sputter target such that a magnetic permeability of the ferromagnetic material is reduced from an intrinsic value in at least a portion of the sputter target. The method of claim 1, wherein the ferromagnetic material is Co, CoCr, CoCrPt, CoCrTa, CoNiCr, CoCrPtTa, CoCrPtTaNb, CoCrPtTaB, CoCrPtTaMo, CoFe, CoNiFe, CoNb, CoNbZr, CoTr, Ni, Fe, CoZr A method for producing low permeability, non-planar ferromagnetic sputter targets selected from the group consisting of FeCo and FeNi. The method of claim 1, wherein the target blank is deformed into a dish shape having a bottom, sidewalls, and a curved or angled region by deforming at least one material of the target blank, which becomes the curved or angled region of the sputter target. And thus the magnetic permeability of the ferromagnetic material is reduced from inherent magnetic permeability in at least the curved or angular regions of the sputter target. The method of claim 1, wherein the target blank is deformed by a method selected from the group consisting of spinning, press forming, roll forming, deep drawing, shallow drawing, deep extrusion, stamping, punching, drop hammer forming and explosion forming. A method for fabricating low permeability nonplanar ferromagnetic sputter targets. Non-planar ferromagnetic sputter targets for use in magnetron cathode sputtering comprising a material selected from the group consisting of cobalt, nickel, iron and alloys thereof having a magnetic permeability lower than the intrinsic magnetic permeability in at least one portion of the target. . 6. The non-planar ferromagnetic sputter target of claim 5, wherein the magnetic permeability of the material is lowered in at least one region where most sputtering occurs. 6. The method of claim 5, wherein the sputter target has a dish shape having a bottom, a sidewall portion and a curved or angular region, wherein the magnetic permeability of the ferromagnetic material is at least one curved or angular region of the sputter target. Non-planar ferromagnetic sputter targets smaller than the intrinsic magnetic permeability of the. The method of claim 5, wherein the material is Co, CoCr, CoCrPt, CoCrTa, CoNiCr, CoCrPtTa, CoCrPtTaNb, CoCrPtTaB, CoCrPtTaMo, CoFe, CoNiFe, CoNb, CoNbZr, CoTaZr, Co, FeCr, Ni, FeFe, Ni And non-planar ferromagnetic sputter targets selected from the group consisting of FeNi. 6. The non-planar ferromagnetic sputter target of claim 5, wherein the sputter target has a magnetic leakage flux of at least 150 gauss at the sputter surface of the sputter target. A non-planar ferromagnetic sputter target for use in magnetron cathode sputtering comprising inherent magnetic permeability material greater than 1.0, The target includes a modified region having a magnetic permeability lower than the intrinsic magnetic permeability of the material, wherein the material is Co, CoCr, CoCrPt, CoCrTa, CoNiCr, CoCrPtTa, CoCrPtTaB, CoCrPtTaB, CoCrPtTaMo, CoFe, CoNib, CoZr Non-planar ferromagnetic sputter targets selected from the group consisting of CoTaZr, CoZrCr, Ni, NiFe, NiFeCo, Fe, FeTa, FeCo and FeNi.