HK1118940A - Metal oxynitride adhesion/corrosion barrier layer and a diamond-like carbon overcoat - Google Patents

Description

Metal oxynitride adhesion/corrosion barrier layer and diamond-like carbon overcoat

Technical Field

The present invention relates to the fabrication of Hard Disk Drives (HDDs), and in particular to a method of protecting magnetic heads and disks by using a diamond-like carbon coating on the underlayer that also serves as a corrosion barrier.

Background

Reducing the head-to-disk spacing (fly height) between the magnetic read/write head and the surface of the rotating disk beneath it has been one of the important ways to achieve ultra-high recording densities in Hard Disk Drive (HDD) storage systems. For commercially available HDDs with 160 gigabyte capacity, the flying height is on the order of 10 nanometers (nm). Maintaining such a small spacing between the rapidly rotating disk and the read/write head that substantially floats thereon is difficult and incidental contact between the disk surface and the head is inevitable. When such contact occurs, damage to the magnetic head and the magnetic disk and loss of information recorded on the magnetic disk may result. To minimize head and disk damage, a thin layer of DLC (Diamond like carbon) coating is applied to the surface of the head and the surface of the disk. The DLC also serves to protect the magnetic material in the head from corrosion by various elements within the environment. Given the importance of the role of DLC, it is essential that DLC be hard, dense and thin, requiring thinness to meet overall float height requirements without running out of any allocated spacing. DLC coatings of between 20-30 angstroms are currently found in the prior art.

Conventionally, the DLC coating thickness is greater thanAnd for this thickness range there is high internal stress resulting in poor adhesion to the base material of the magnetic head and other substrates to which they may be bonded. Because of high internal and thermal stresses, an adhesive layer is required. For example, in cutting edge and drilling tool applications, DLC thicknesses in the micron range and operating temperatures of several hundred degrees celsius, the Coefficient of Thermal Expansion (CTE) of the bond layer also plays an important role. For these reasons, in the prior art, Japanese patents JP2571957, JP2220522 and JP3195301 have proposed Si, SiO_xSiC and SiN_xFor the adhesive layer. Itoh et al (U.S. Pat. No. 5,227,196) discloses SiN on an oxide substrate below a DLC layer_xAnd (7) bonding the layers. Various types of adhesive layers are also found in the prior art. Ishiyama (us patent application 2006/0063040) discloses a carbon-based protective layer of hydrogenated carbon nitride for better adhesion. Hwang et al (U.S. patent application 2005/0045468) teaches a Si adhesion layer for DLC. Hwang et Al (U.S. patent application 2002/0134672) disclose Si, Al₂O₃、SiO₂Or SiN_xAs an adhesion layer under the DLC layer. David et al (U.S. patent No. 5,609,948) describes a SiC adhesion layer underlying a DLC layer.

In addition to these cited prior art, adhesive layers comprising materials other than Si have also been utilized. Natsume et al (U.S. patent No. 7,091,541) discloses TiAlON oxynitride for use in the adhesion layer between the capacitor dielectric layer and the electrode. Fu et al (U.S. patent application No. 6,238,803) show TiO_xN_yAnd a barrier layer. Johnson et al (U.S. patent No. 4,952,904) describe a metal oxide bonding layer between silicon nitride and platinum. Stevens (U.S. patent No. 5,070,036) shows metal oxynitrides as one of the various material regions in VLSI circuits. Gilley (U.S. patent No. 4,861,669) shows a TiON dielectric film.

For a magnetic head, the underlayer should have at least the following properties:

1. electrical isolation properties. For magnetic heads, electrical isolation must be provided for magnetic metal alloy layers, such as those comprising magnetoresistive read heads based on the Giant Magnetoresistance (GMR) effect, or those comprising devices based on the Tunneling Magnetoresistance (TMR) effect. Electrical shorts between these layers and surrounding HDD components will damage the magnetic head or similar device. Thus, the protective layer, in particular the lower layer, should be insulating or semi-insulating. However, due to the semiconductor properties of Si, surface shunting of the Si adhesion layer may introduce noise, such as so-called popcorn noise, into the GMR or TMR reader.

2. Corrosion resistance. DLC films, particularly those produced by the Filtered Cathode Vacuum Arc (FCVA) process of the prior art, are typically embedded with micro or nano particles. These particles can cause pinholes and corrosion of the materials used to form the magnetically active layer, such as NiFe and NiCoFe. The corrosion resistance of the underlying layer is therefore critical to maintain the performance integrity of the sensor.

3. And (4) abrasion resistance. In the case where the total thickness of the underlayer and the DLC layer is reduced to the sub-30 angstrom range, virtually every atom plays a role in protection. Thus, if we can put more atoms into a limited film thickness, better wear resistance can be expected. It is therefore very important that the under layer has both a chemical stability for corrosion protection and a high hardness which is advantageous for friction.

It is an object of the present invention to provide a new class of materials with which to form an underlayer to replace Si and related materials described in the above prior art.

Disclosure of Invention

A first aspect of the invention provides a thin protective layer for a magnetic read/write head or magnetic recording medium to protect them from inadvertent contact and to provide wear resistance between the head and the medium surface.

A second aspect of the present invention provides a protective layer formed as a bilayer, wherein the upper layer is primarily the protective layer and the lower layer is primarily the adhesion enhancing layer and the corrosion protection layer.

A third aspect of the present invention provides such a bilayer wherein the inherently high resistivity of the underlayer eliminates surface shunting, thus reducing noise, such as popcorn noise, from the read/write head.

A fourth aspect of the invention provides such a bilayer wherein the lower layer forms a strong and stable chemical bond with the upper layer.

A fifth aspect of the present invention provides a method for forming a protective bilayer that meets all of the above objectives.

The object of the invention is to obtain an adhesion-enhancing and corrosion-resistant underlayer for forming a protective bilayer by using a material of the class which is a transition metal oxynitride with MeO_xN_yIn the general formula, "Me" represents a transition metal. Examples of transition metals that will meet the objectives of the present invention are Ti, Zr, Hf, V, Nb, Ta, Cr, Mo and W in groups IIIB, IVB and VB of the periodic Table. The transition metal oxynitride can effectively bond to the DLC and the read/write head substrate and the recording medium substrate to form a strong and stable bond. Which has the necessary chemical and mechanical properties to meet the objects of the invention set forth above. Ti, Zr, Hf, V, Nb, Ta, Cr, Mo and W are refractory metals that form carbides that exhibit good adhesion to DLC films. In addition, they also exhibit compatibility with substrate materials used in magnetic read heads and media such as AlTiC, Al₂O₃NiFe and NiFeCo, as well as a variety of other materials widely used in the semiconductor industry. Thus, Ti, Cr, and Ta have been widely used for the adhesion layer. In addition, the chemical, mechanical and physical properties of transition metal oxynitrides can be tailored from covalently dominated nitrides to ionically dominated oxides by varying the oxygen and nitrogen concentrations x and y in the formula. For example, TiN is a good material for the adhesion layer, but its resistance (see FIG. 1) is only 10^-6Range of Ohm cm. However, its resistivity can be increased to 10 by introducing oxygen⁺⁵-10⁺¹⁰The range between ohm cm (see "The physicochemical properties of TiO", M.J. Jung et al_xN_yfiles with controlled gene partial compression ", Surface Coating Technology 171, pp.71-74, 2003). Together with this favorable variation in resistivity, the stress of the film will also be advantageously reduced (S.S. Ang, "Titanium Nitride Films with High Oxygen Concentration" Journal of electronic materials, Vol.17, No.2, pp.95-100, 1988).

Another example that meets the objectives of the present invention is TaO_xN_yTypes of films, as described below, which can be formed by using Ar/O₂/N₂Ion beam and reactive sputtering of a Ta target. As shown in FIG. 1, TaO is introduced_xN_yThe increase in the x/y ratio in the film from about 0 to 20 provides a hardness tuning between about 26GPa to 12 GPa. At the same time, the band gap energy Eg increases from approximately 2.7eV to 4.2 eV. As a result, the resistivity will also increase accordingly. The ability to adjust membrane performance by varying the oxygen/nitrogen ratio is a very advantageous aspect of the present invention.

Yet another example is CrO_xN_yFilm type which can pass through Cr target and Al/O₂/N₂By reactive sputtering. Electrical property of material dependent on CrO_xN_yChange from CrN to CrO_1.5Changing from conductive to insulative.

A further example is MoO_xN_yType wherein an increase in oxygen content in the film reduces the hardness of the film from about 25GPa to about 5 GPa. At the same time, the Young's modulus also decreased from 250GPa to about 50 GPa. The stress decreases from about 1.5GPa to a stress close to zero.

For reference and comparison purposes, FIG. 2 provides a conventional listing of several relevant mechanical and electrical properties of various materials used in the fabrication of magnetic read/write heads.

MeO_xN_yThe lower layer can be prepared by various methods, including:

1. gold (Au)Metal, metal oxide, metal nitride or metal oxynitride target in Ar/O₂/N₂Reactive sputtering in an atmosphere.

2. Plasma treatment of metal films using Plasma Immersion Ion Implantation (PIII), Plasma Immersion Ion Implantation Deposition (PIIID).

Drawings

The objects, features and advantages of the present invention will be understood in the context of the description of the preferred embodiments set forth below. The description of the preferred embodiments is understood within the context of the accompanying drawings, in which:

figure 1 is a graph of the hardness of tantalum oxynitride as a function of the relative percentages of oxygen and nitrogen.

FIG. 2 is a table listing several relevant properties of materials used to form the read/write head and its protective coatings.

Fig. 3a and 3b are flow charts of a prior art method of forming a protective bilayer (3a) and a method of forming a protective bilayer (3 b).

FIG. 4 is a schematic diagram of a slider mounted read/write head of the type on which the protective bilayer of the present invention is to be formed. The slider floats on top of a rotating magnetic disk of this type, which is also protected by the bilayer of the present invention.

FIG. 5 is a schematic diagram of an apparatus for making a particularly preferred embodiment of the invention using reactive ion beam sputtering.

Fig. 6 is a schematic diagram of an apparatus for making a particularly preferred embodiment of the invention using a scanned focused ion beam.

Fig. 7 is a schematic diagram of an apparatus for making a particularly preferred embodiment of the invention using a pulsed ion beam.

FIG. 8 is a schematic diagram of an apparatus for making a particularly preferred embodiment of the invention using a high energy laser.

Fig. 9 is a schematic diagram of an apparatus for making a preferred embodiment of the invention using ion beam sputtering in the presence of plasma or subsequent processing in the plasma.

Detailed Description

Each of the preferred embodiments of the present invention teaches a method of fabricating a thin protective bilayer over a magnetic read/write head or magnetic recording medium, wherein the protective bilayer comprises a transition metal oxynitride MeO formed as_xN_y(where Me represents a single transition metal element or an alloy formed from two or more of the following transition metal elements: Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, and W) is used to form a hard, protective diamond-like carbon (DLC) overlayer (also referred to as an overlayer) thereon.

Amorphous Si (a-Si) is an adhesion layer widely used in the magnetic recording industry to improve adhesion of DLC layers to substrates of magnetic read/write heads. In the prior art, the coating process starts with the use of Ar⁺The ion beam cleans the head substrate. After this cleaning process, an adhesion layer of amorphous Si is deposited using ion beam sputtering and then the DLC upper layer is deposited using Ion Beam Deposition (IBD) or PECVD or, more preferably, Filtered Cathode Vacuum Arc (FCVA) deposition.

The preferred embodiment of the present invention differs from IBD deposition of a-Si because of the completely different class of materials, transition metal oxynitrides, are formed to act as adhesion and corrosion protection layers. In a preferred embodiment, the layer is formed (or on the head or recording medium) as a MeO_xN_yLayer, Me represents a single element or an alloy formed of two or more of the following transition metal elements: ti, Zr, Hf, V, Nb, Ta, Cr, Mo, and W in groups IIIB, IVB, and VB of the periodic Table. This layer may be deposited by reactive ion sputtering, Plasma Enhanced Chemical Vapor Deposition (PECVD), reactive Pulsed Laser Deposition (PLD), and other methods described below.

Referring to the flow chart of FIG. 3a, three sequential steps are shown for making a prior art protective bilayer.

1. Using Ar⁺The ion beam acts as an etching mechanism to pre-clean the substrate.

2. An adhesion underlayer of amorphous silicon (a-Si) is deposited using reactive ion sputtering.

3. A protective upper layer of DLC is deposited using IBD, PECVD or FCVA.

Referring to the flow chart of FIG. 3b, there are shown three sequential steps for making the protective bilayer of the present invention.

1. Using Ar⁺The substrate (of the head or media) is pre-cleaned as an etching mechanism.

2. At Ar/O₂/N₂Depositing MeO in an atmosphere from such a metal oxide, metal nitride, or metal oxynitride target using sputtering of a refractory transition metal (Me) or an alloy of such a metal, or by using plasma immersion ion implantation, plasma immersion ion implantation deposition, or reactive pulsed laser deposition_xN_yAdhesion enhancement and corrosion resistance of the underlying layer.

3. The protective upper layer of DLC is deposited using IBD, PECVD or FCVA.

The following embodiments of the present invention are all methods by which a protective layer may be formed on a magnetic read/write head or a magnetic recording medium (typically a magnetic disk), which will satisfy all of the objects of the present invention set forth above. In all embodiments, the protective layer is formed as a bilayer on the surface of the disk or suitable substrate of the read/write head, such as already formed by Ar ions or Ar/O, for example₂A suitable method of ion beam etching cleans the Air Bearing Surface (ABS). It will also be appreciated that it is preferred to have a plurality of read/write heads mounted on a carriage and processed simultaneously by the method.

FIG. 4 shows the head-disk interface (not drawn to scale), where the head slider (10) is mechanically attached to its suspension (110). Slider and shield GMR or TMR read-outA writer or writer (150) and Al₂O₃An overlayer (170) is built on the AlTiC substrate (120). The reader shield, reader and writer materials are primarily formed of magnetic materials including various alloys and compounds of Ni-Fe-Co, which are subject to corrosion when exposed to pre-ambient conditions. The slider is covered with an underlayer (180) of the present invention and an overlayer (190) of DLC.

On the other hand, the disk (20) is built on a glass or aluminum substrate (210) on top of which is an adhesive layer (220) (not typical in the present invention) and a magnetic layer (230). The surface of the magnetic layer is protected by an adhesion layer (280) formed by the method of the present invention and an upper DLC coating (290). To minimize wear with the slider, a lubrication layer (260) is applied to the disk. The invention provides an adhesive layer for both the slider (180) and the disk (280).

First preferred embodiment

Referring now to FIG. 5, there is shown a schematic perspective view of a device in which the protective bilayer of the present invention may be formed on a magnetic read/write head or on the surface of a magnetic recording disk. In this first preferred embodiment, as an example of a method, the adhesion enhancing layer will be formed as TiO_xN_yAnd (3) a layer.

The first preferred embodiment of the present invention uses a deposition chamber (10) in which less than about 10 is formed by a turbo pump (not shown)^-6Vacuum of the tray. This cavity is essentially a common element in all the following embodiments. Subjecting a reactive ion beam such as Ar⁺A beam (20) is injected into the cavity and directed towards the TiO₂(50) A sputtering target. The beam is generated by an RF source (30) and accelerated by a voltage that generates an ion beam at a beam voltage of between about 300V and 1200V. The injection port (40) allows O₂And N₂The gas is injected into the chamber (10) or ion source at flow rates of about 0 and 20sccm and at different concentration ratios and different durations, depending on the TiO_xN_yThe desired x/y ratio in the lower layer, x being in the range of about 0 to 3 and y being in the range of about 0 to 2. As explained above, Ar⁺Beam-oriented TiO₂Sputtering target (5)0) And the sputtered atoms (60) impinge on a coated device (70) (deposition target) which may be a read/write head or a magnetic disk mounted on a rotatable support (80) that rotates for uniform deposition. The above values of x and y produce a bond and corrosion resistant underlayer having a resistivity of about 10^-6To 10⁺⁶In the ohm cm range. It should also be noted that x and y may be varied as the deposition process proceeds to produce a bond layer having a composition that is a function of layer thickness. In all of the formations of examples one to six, a total thickness of the adhesive layer of not more than 50 angstroms can satisfy the object of the present invention. Adhesion layer thicknesses of less than 20 angstroms are most preferred, although adhesion layers less than 50 angstroms will meet the objectives of the present invention. After the adhesion layer is deposited, a DLC layer (not shown) is formed on the adhesion layer using the methods described above to produce a bonded bilayer that meets the objectives of the present invention.

It should be noted that where Ti is a transition metal and TiO₂The formation of the above-described layer as a target can also be formed in substantially the same manner using a target including a compound of Me, where Me represents a single element or an alloy formed with two or more of the following transition metal elements: ti, Zr, Hf, V, Nb, Ta, Cr, Mo, and W.

After the lower layer is formed, a DLC upper layer is formed on the lower layer using the method described above.

In a second version of the same first embodiment, the apparatus of FIG. 5 is used as above, but the sputter target material (50) is TiN. Ar (Ar)⁺The beam (20) is implanted using an RF source and an accelerating voltage that generates a beam voltage of between about 300V and 1200V and O₂And N₂The gas is injected into the chamber (10) at a flow rate between about 0 and 20sccm and at different concentration ratios and different durations, depending on the TiO_xN_yThe desired x/y ratio of the lower layer, x being in the range of about 0 to 3 and y being in the range of about 0 to 2. When Ar is⁺When the beam hits the TiN sputtering target (50), the resulting sputtered Ti and N atoms (60) are in the injected O₂And N₂Impinging the read/write head or disk (70) in the presence of a gas to generateProduction of desired TiO_xN_yAnd (7) bonding the layers. A plurality of read/write heads or disks are mounted on a rotatable support (80) that rotates for uniform deposition.

It should also be noted that x and y may be varied as deposition proceeds to grow a bond layer having a composition that is a function of layer thickness. In all of these formations, a total thickness of the layer of no more than about 50 angstroms produces results that meet the objectives of the present invention. Layer thicknesses of less than 20 angstroms are most preferred.

It should be noted that the formation of the above-described layer in which Ti is the transition metal and the sputtering target is TiN can be performed in substantially the same manner using a target including a compound of Me, where Me represents a single element of the following transition metal elements or an alloy formed in two or more kinds: ti, Zr, Hf, V, Nb, Ta, Cr, Mo, and W.

After the lower layer is formed, a DLC upper layer is formed on the lower layer using the methods described above.

Second preferred embodiment

The second preferred embodiment of the invention uses the apparatus of fig. 6, which is similar to the apparatus of fig. 5 in that: it includes a deposition chamber (10), a reactive ion beam (20) such as Ar⁺An ion beam can be implanted into the deposition chamber (10) and directed toward a Ti sputtering target (50); while the injection port (40) allows O₂And N₂The gas is injected at flow rates of about 0 and 20sccm and at different concentration ratios and different durations, depending on the TiO_xN_yThe desired x/y ratio in the lower layer, x being in the range of about 0 to 3 and y being in the range of about 0 to 2. However, in this embodiment, the reactive ion beam is high-energy scanning focused Ar⁺An ion beam (25) directed at a sputtering target (20) of Ti and the sputtered atoms (60) impinge on a read/write head or disk target (70) mounted on a rotatable support that rotates for uniform deposition. To avoid poisoning the target and eliminating the hysteresis effects associated with deposition, a high energy scanning focused ion beam described by t.nyberg et al (U.S. patent application 2004/0149566a1), the full disclosure of which is incorporated herein by referenceThe contents of which are incorporated herein by reference. It should also be noted that x and y may be varied as the deposition process proceeds to produce an adhesive layer having a composition that is a function of layer thickness. In all of these formations, a total thickness of the layer of no more than 50 angstroms produces results that meet the objects of the present invention. Layer thicknesses of less than 20 angstroms are most preferred.

It should be noted that the formation of the above-described layer in which Ti is the transition metal can be performed in substantially the same manner using a target of a compound including Me, where Me represents a single element or an alloy formed in two or more of the following transition metal elements: ti, Zr, Hf, V, Nb, Ta, Cr, Mo, and W.

After the lower layer is formed, a DLC upper layer is formed on the lower layer using the method described above.

Third preferred embodiment

A third preferred embodiment of the present invention uses the apparatus of FIG. 7, which includes a deposition chamber (10), a reactive ion beam such as Ar⁺An ion beam can be implanted into the deposition chamber (10) and directed toward a Ti sputtering target (50); while the injection port (40) allows O₂And N₂The gas is injected at flow rates of about 0 and 20sccm and at different concentration ratios and different durations, depending on the TiO_xN_yThe desired x/y ratio in the lower layer, x being in the range of about 0 to 3 and y being in the range of about 0 to 2. However, in this embodiment, the ion beam (20) is pulsed Ar with high instantaneous power⁺An ion source directed at a sputtering target (50) of Ti and the sputtered atoms (60) impinge on a deposition target read/write head (70) mounted on a rotatable support that rotates for uniform deposition. To avoid poisoning the target and eliminating hysteresis effects associated with deposition, a high instantaneous power pulsed ion beam described by v.kousnetsov et al (U.S. patent application 6,296,742), the entire contents of which are incorporated herein by reference, is used. It should also be noted that x and y may be varied as the deposition process proceeds to produce an adhesive layer having a composition that is a function of layer thickness. In all of these formations, no more than 50 angstromsThe total thickness of the layers of (a) yields results that meet the objects of the present invention. Layer thicknesses of less than 20 angstroms are most preferred.

It should be noted that the formation of the above-described layer in which Ti is the transition metal can be performed in substantially the same manner using a target of a compound including Me, where Me represents a single element or an alloy formed in two or more of the following transition metal elements: ti, Zr, Hf, V, Nb, Ta, Cr, Mo, and W.

After the lower layer is formed, a DLC upper layer is formed on the lower layer using the method described above.

Fourth preferred embodiment

A fourth preferred embodiment of the present invention uses the apparatus of FIG. 8, which includes a deposition chamber (10) into which a high energy pulsed laser can direct high energy pulsed electromagnetic radiation (25) toward a Ti target (50) while an injection port (40) allows O₂And N₂The gas is injected at flow rates of about 0 and 20sccm and at different concentration ratios and different durations, depending on the TiO_xN_yDesired x/y ratio in the lower layer. In this embodiment, the electromagnetic radiation may be generated by a high energy pulsed laser such as CO₂The atoms generated by the laser, excimer laser, etc. and emitted by the laser beam impinge upon a target read/write head or magnetic disk (70), which read/write head or magnetic disk (70) is mounted on a rotatable support that rotates for uniform deposition. An x value in the range of about 0 to 3 and a y value in the range of between about 0 to 2 are obtained and an adhesive layer satisfying the object of the present invention is produced. It should also be noted that x and y may be varied as the deposition process proceeds to produce an adhesive layer having a composition that is a function of layer thickness. In all of these formations, a total thickness of the layer of no more than 50 angstroms produces results that meet the objects of the present invention. Layer thicknesses of less than 20 angstroms are most preferred.

It should be noted that the formation of the above-described layer in which Ti is the transition metal can be performed in substantially the same manner using a target of a compound including Me, where Me represents a single element or an alloy formed in two or more of the following transition metal elements: ti, Zr, Hf, V, Nb, Ta, Cr, Mo, and W.

After the lower layer is formed, a DLC upper layer is formed on the lower layer using the method described above.

Fifth preferred embodiment

Referring to FIG. 9, there is shown a schematic perspective view of an apparatus in which a two-step process for forming a protective bilayer on a magnetic read/write head is performed in accordance with a fifth preferred embodiment.

A fifth preferred embodiment of the present invention uses the deposition chamber (10) of FIG. 7, a reactive ion beam such as Ar⁺A beam (20) is injected into the deposition chamber (10). The beam is generated by an RF source (30) and accelerated by voltages that produce an ion beam at a beam voltage in the range of about from 300V to 1200V. The beam (20) impinges on a Ti sputtering target (50) causing Ti atoms to sputter onto a plurality of magnetic read/write heads or disks (70), the plurality of read/write heads or disks (70) being mounted on a rotatable fixture that rotates for uniform deposition.

After depositing Ti sputtered film on read/write head or magnetic medium, the Ti film is exposed to Ar/O₂And Ar/N₂A plasma (90) of a gas, the plasma being respectively treated with O₂And N₂Different concentrations and durations of injection into the cavity (10) depending on the TiO_xN_yThe desired value of the x/y ratio in (1). An x value in the range of about 0 to 3 and a y value in the range of between about 0 to 2 are obtained and an adhesive layer satisfying the object of the present invention is produced. It should also be noted that x and y may be varied as the deposition process proceeds to produce an adhesive layer having a composition that is a function of layer thickness. In all of these formations, a total thickness of the layer of no more than 50 angstroms produces results that meet the objects of the present invention. Layer thicknesses of less than 20 angstroms are most preferred.

It should be noted that the formation of the above-described layer in which Ti is the transition metal can be performed in substantially the same manner using a target of a compound including Me, where Me represents a single element or an alloy formed in two or more of the following transition metal elements: ti, Zr, Hf, V, Nb, Ta, Cr, Mo, and W.

The plasma may be generated and applied using any number of methods known in the art, such as plasma formation from an ion beam, formation and application of a Capacitively Coupled Plasma (CCP), formation of Electron Cyclotron Resonance (ECR), or formation and application of an Inductively Coupled Plasma (ICP).

After the lower layer is formed, a DLC upper layer is formed on the lower layer using the method described above.

Sixth preferred embodiment

The sixth preferred embodiment of the present invention is substantially the same as the fifth embodiment except that the injection of plasma occurs when the sputter beam strikes the read/write head or the magnetic disk. This embodiment uses the deposition chamber (10) of FIG. 9, a reactive ion beam such as Ar⁺A beam (20) is injected into the deposition chamber (10). The beam is generated by an RF source (30) and accelerated by voltages that produce an ion beam at a beam voltage in the range of about from 300V to 1200V. The beam (20) impinges on a Ti sputtering target (50) causing Ti atoms to sputter onto a plurality of magnetic read/write heads or disks (70), the plurality of read/write heads or disks (70) being mounted on a rotatable fixture that rotates for uniform deposition.

In the presence of Ar/O₂And Ar/N₂Plasma (90) of gas, deposition of Ti sputtered film on the read/write head or disk (70), the Ar/O₂And Ar/N₂Plasma (90) of gas with O formed in the chamber (10)₂And N₂Of (or subsequent exposure to Ar/O for different exposure durations)₂And Ar/N₂Plasma (90)) of gas, depending on TiO_xN_yDesired ratio of x/y in (1). The plasma may be generated and applied using any number of methods known in the art, such as plasma formation from an ion beam, formation and application of a Capacitively Coupled Plasma (CCP), formation of Electron Cyclotron Resonance (ECR), or formation and application of an Inductively Coupled Plasma (ICP).

An x value in the range of about 0 to 3 and a y value in the range of about 0 to 2 are obtained and produce an adhesion enhancing and corrosion resistant underlayer that meets the objectives of the present invention. It should also be noted that x and y may be varied as the deposition process proceeds to produce an adhesive layer having a composition that is a function of layer thickness. In all of these formations, a total thickness of the layer of no more than 50 angstroms produces results that meet the objects of the present invention. Layer thicknesses of less than 20 angstroms are most preferred.

Note that the formation of the above-described layer in which Ti is the transition metal can be performed in substantially the same manner using a target of a compound including Me, where Me represents a single element or an alloy formed in two or more of the following transition metal elements: ti, Zr, Hf, V, Nb, Ta, Cr, Mo, and W.

After the lower layer is formed, a DLC upper layer is formed on the lower layer using the method described above.

As will be appreciated by those skilled in the art, the preferred embodiments of the present invention are illustrative of the present invention and not limiting thereof. Modifications and variations may be made in the methods, processes, materials, structures, and dimensions by which a protective bilayer including a transition metal oxynitride adhesion enhancing and corrosion resistant underlayer may be formed on a magnetic read/write head while still providing such a protective bilayer formed in accordance with the present invention as defined by the appended claims.

Claims (41)

1. A protected magnetic read/write head or recording disk comprising:

the read/write head or recording disk;

a protective bilayer formed over the read/write head or the recording disk, the bilayer further comprising:

forming a transition metal oxynitride MeO on the clean substrate surface of the read/write head or recording disk_xN_yThe adhesion enhancement and corrosion resistance of the lower layer;

a diamond-like carbon outer layer formed on the lower layer.

2. The protected read/write head or recording disk of claim 1 wherein Me represents a single element or an alloy formed in two or more of the following transition metal elements: ti, Zr, Hf, V, Nb, Ta, Cr, Mo, and W.

3. The protected read/write head or recording disk of claim 1, wherein x is in a range between about 0 and 3 and y is in a range between about 0 and 2.

4. The protected read/write head or recording disk of claim 1, wherein the underlayer is formed to a thickness of less than about 50 angstroms.

5. The protected read/write head or recording disk of claim 1, wherein the underlayer is formed to a thickness of less than about 20 angstroms.

6. The protected read/write head or recording disk of claim 1, wherein the total thickness is formed to a thickness of less than about 50 angstroms.

7. The protected read/write head or recording disk of claim 1, wherein x and y vary as a function of the thickness of the underlayer.

8. The protected read/write head or recording disk of claim 1 wherein the underlayer is formed by a process of reactive pulsed laser deposition, reactive ion sputtering, pulsed reactive ion sputtering, or scanned focused reactive ion beam sputtering in the presence of oxygen and nitrogen gas or oxygen and nitrogen plasma.

9. A method of forming a protected magnetic recording disk, a protected read/write head, or a plurality of protected read/write heads, comprising:

providing the magnetic recording disk, the read/write head, or a plurality of read/write heads;

cleaning a suitable surface of the disk, the read/write head, or the plurality of read/write heads;

forming on said surface a compound having the general formula MeO_xN_yThe transition metal oxynitride of (1) enhances the adhesion and resists the lower layer with corrosion;

a diamond-like carbon layer is formed on the lower layer.

10. A process according to claim 9 wherein Me represents a single element or an alloy formed in two or more of the following transition metal elements: ti, Zr, Hf, V, Nb, Ta, Cr, Mo, and W.

11. The method of claim 9, wherein the lower layer is formed by a process comprising:

providing a vacuum deposition chamber comprising a rotatable support, a sputter target, means for implanting a reactive ion beam at a selected energy and directing said ions toward said sputter target, means for implanting various gases at a selected flow rate and maintaining said gases at a desired relative concentration within said chamber;

mounting the read/write head or heads on the support;

directing said reactive ions toward a sputter target comprising a refractory transition metal Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, or W, an oxide or nitride, either alone or in combination, or as either alone or in combination;

injecting O at different concentrations and for different durations₂Gas and N₂Gas while the reactive ions collide on the target and while rotating the support for uniform deposition, thus forming the MeO on the read/write head or heads_xN_yThe adhesive layer of (1).

12. The method of claim 11, wherein x is in a range between about 0 and 3 and y is in a range between about 0 and 2.

13. The method of claim 11, wherein said O is₂And N₂The gas is injected at a flow rate between about 0 and 20 sccm.

14. The method of claim 11, wherein the reactive ion beam is pulsed or stabilized Ar with a beam voltage between about 300V and 1200V⁺Ion beam, and the sputtering target is TiN or TiO₂Target, and the lower layer is formed of TiO_xN_yAnd (3) a layer.

15. The method of claim 11, wherein x and y are made to vary as the underlying layer is formed.

16. The method of claim 11, wherein the adhesion layer is formed to a thickness of less than about 50 angstroms.

17. The method of claim 9, wherein the adhesive layer is formed by a process comprising:

providing a vacuum deposition chamber comprising a rotatable support, a sputter target, a laser for directing a pulsed beam of energetic reaction of electromagnetic radiation at said sputter target, means for injecting various gases at selected flow rates within said chamber and maintaining said gases at desired concentrations for desired durations;

mounting the magnetic recording disk, the read/write head, or a plurality of such heads on the support;

directing said electromagnetic radiation at a target comprising a refractory transition metal, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, or W, an oxide or nitride, either alone or in combination, or as either alone or in combination;

mixing O with₂Gas and N₂Gas is injected at different concentrations and for different durations while the reactive ions collide on the target and while the support rotates for uniform deposition, thus forming on the read/write head or headsMeO_xN_yThe lower layer of (2).

18. The method of claim 17, wherein x is in a range between about 0 and 3 and y is in a range between about 0 and 2.

19. The method of claim 17, wherein x and y are made to vary with the formation of the underlayer.

20. The method of claim 17, wherein the underlayer is formed to a thickness of less than about 20 angstroms.

21. The method of claim 17, wherein the underlayer is formed to a thickness of less than about 50 angstroms.

22. The method of claim 9, wherein the lower layer is formed by a process comprising:

providing a vacuum deposition chamber comprising a rotatable support, a sputter target, means for implanting a reactive ion beam at a selected energy and directing said ions towards said sputter target, means for forming a plasma within said chamber, said plasma being formed from Ar/O₂Gas and Ar/N₂Gases are formed at different concentrations;

mounting the read/write head or heads on the support;

directing said reactive ion beam at a sputter target comprising a single or a combination of refractory transition metals Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, or W, whereby said single or a combination of refractory transition metal layers can be formed on said read/write head or heads while rotating said support for uniform deposition; then the

After the refractory transition metal layer is formed, the Ar/O is formed in different relative concentration ratios₂Gas and Ar/N₂A plasma of a gas in which the refractory transition metal layer is immersedIn the plasma, simultaneously rotating the support and thus forming the MeO on the read/write head or heads_xN_yThe lower layer of (2).

23. The method of claim 22, wherein x is in a range between about 0 and 3 and y is in a range between about 0 and 2.

24. The method of claim 22, wherein x and y are made to vary with the formation of the underlayer.

25. The method of claim 22, wherein the underlayer is formed to a thickness of less than about 50 angstroms.

26. The method of claim 22, wherein the underlayer is formed to a thickness of less than about 20 angstroms.

27. The method of claim 22, wherein the reactive ion beam is Ar having a beam voltage of between about 300V and 1200V⁺An ion beam.

28. The method of claim 9, wherein the lower layer is formed by a process comprising:

providing a vacuum deposition chamber comprising a rotatable support, a sputter target, means for implanting a reactive ion beam at a selected energy and directing said ions towards said sputter target, means for forming a plasma within said chamber, said plasma being formed from Ar/O₂Gas and Ar/N₂Gases are formed at different concentrations;

mounting the read/write head or heads on the support;

directing said reactive ion beam toward a sputter target comprising a single or a combination of refractory transition metals Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, or W, thereby forming said single or a combination of refractory transition metal layers on said read/write head or heads; then the

Forming the Ar/O₂Gas and Ar/N₂A plasma of gas in which the transition metal layer is immersed while the layer is formed and the support is rotated for uniform deposition, and thus the MeO is formed on the read/write head or heads_xN_yThe lower layer of (2).

29. The method of claim 28, wherein the plasma is formed sequentially from Ar/O₂Plasma and Ar/N₂The plasma being applied for different durations or sequentially from Ar/N₂Plasma and Ar/O₂The plasma is applied for different durations.

30. The method of claim 22, wherein the plasma is formed as an ion beam plasma, an electron cyclotron resonance plasma, an inductively coupled plasma, or a capacitively coupled plasma.

31. The method of claim 28, wherein the plasma is formed as an ion beam plasma, an electron cyclotron resonance plasma, an inductively coupled plasma, or a capacitively coupled plasma.

32. The method of claim 28, wherein the reactive ion beam is Ar having a beam voltage of between about 300V and 1200V⁺An ion beam.

33. The method of claim 25, wherein x is in a range between about 0 and 3 and y is in a range between about 0 and 2.

34. The method of claim 28, wherein x and y are made to vary with the formation of the underlayer.

35. The method of claim 28, wherein the underlayer is formed to a thickness of less than about 50 angstroms.

36. The method of claim 28, wherein the underlayer is formed to a thickness of less than about 20 angstroms.

37. The method of claim 9, wherein the lower layer is formed by a process comprising:

providing a vacuum deposition chamber comprising a rotatable support, a sputter target, means for implanting a high energy scanned focused beam of reactive ions and directing said ions towards said sputter target, means for implanting various gases within said chamber and maintaining the atmosphere of said gases at a desired relative concentration;

mounting the read/write head or heads on the support;

directing a high energy scanning focused beam of said reactive ions at a target comprising a refractory transition metal, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, or W, oxide or nitride, singly or in combination or as singly or in combination thereof;

mixing O with₂Gas and N₂Gas is injected at different relative concentrations while the reactive ions collide on the target, thus forming a MeO on the magnetic recording disk, the read/write head, or heads_xN_yThe lower layer of (2).

38. The method of claim 37, wherein the reactive ion beam is Ar having a beam voltage of between about 300V and 1200V⁺An ion beam.

39. The method of claim 37, wherein the underlayer is formed to a thickness of less than about 50 angstroms.

40. The method of claim 37, wherein the underlayer is formed to a thickness of less than about 20 angstroms.

41. The method of claim 9, wherein the diamond-like carbon layer is formed by ion beam deposition, plasma enhanced chemical vapor deposition, or filtered cathodic vacuum arc.