WO2013169342A1 - Multi-block sputtering target with interface portions and associated methods and articles - Google Patents

Abstract

A sputtering target that includes at least two consolidated blocks, each block' including an alloy including a first metai (e.g., a refractory metal such as molybdenum in an amount greater than about 30 percent by weight) and at least one additional alloying ingredient; and a joint between the at least two consolidated blocks:, the joint being prepared free of any microstructure derived from a diffusion bond of an added loose powder. A process for making the target includes hot isostatically pressing (e.g., below a temperature of 1080°C), consolidated preform blocks that, prior to pressing, have interposed between- the consolidated powder metal blocks at least one continuous solid interface portion. The at least one continuous solid interface portion may include a cold spray body, which may be a mass of cold spray deposited powders on a surface a block, a sintered preform,, a compacted powder body {e.g,, a tile), or any combination thereof.

Description

f¾ULT!- LOC SPUTTE I a TARGET WITH

INTERFACE PORTIONS AND ASSOCIATED METHODS -AND ARTICLES

CL M OF BENEFIT Of FfLfWG DATE

[801 J The present application claims the benefit of the filing date of United States

Application Serial No, 61/644/568 filed May 9, 2012, and United States Application No. 13/793,043 filed arch 1 1 , 013 the contents of whic are expressl incorporated by reference,

F W OF THE INVEMTSQW

|0O21 The presen t invention relates generally ^"to sputtering , and- more particularly to improved multi-component sputtering targets and their manufacture and use to produce thin films that include a plurality of blocks joined together during a consolidation operation (such a a hot isostaticaliy pressing operation), which, avoids diffusion ondi g of loose powder, to define at least one interface portion.

SAC GROU P OF THE Jk Efcmo^

[003] Sputtering ocesses re employed to deposit thin films onto substrates to manufacture an of a variety of devices. Sputtering processes typically involve bombarding a. solid s utteri g ta ge with e ergiz d particles to eject atoms from the target, in recent years, there has been a growing need fo large area sputtering targets. This is especially so for certain applications i which large sized products ar made. For example, fiat panel displays often require the deposition of uniform thin films onto a substrate. The demand for larger displays, such as for televisions,, continues to strain materials producers to develop alternative approaches to the efficient supply of suc materials.

004| In one specific application, according to U.S. Patent No. 7,336,324 (Kim et al), the deposition of a molybdenum-titanium barrier layer onto a substrate has been employed for the manufacture of a liquid crystal display device. Such application intensifies the need for large display devices capable of delivering such materials, particularly targets that contain both molybdenum and titanium.

[00S1 in the manufacture of large area sputtering targets it is often deemed critical and imperative that the targe exhibit uniformity in composition, microsiruciure, or a combination of both. For some device manufacturers thai rely upon the targets to manufacture devices, the slightest Imperfections are perceived as a potential quality control •risk. By way of example... one concern for manufacturers i the- potential formation of particles (e.g., atomic clusters or aggregates having an atomic composition different, than the atomic composition of other regions of the film) during device manufacture, U.S. Patent No.

6,755,948 (Fukisyo et- l) discusses the potential effects of particles in the context of titanium targets.

[006] Activities in the sputtering target field are illustrated by reference to a number Of patent tings. By way f illustration, U.S. Patent Application No. 20WQQ899& describes the formation of a large area sputtering target by the use of a powder between cQld-isostatical y pressed blocks of a mixture of molybdenum and titanium powders. The use of such powder generally results in the formation of a conspicuous bond line between adjoinin blocks. Even if such bond line does not actually adversely affect performance, its conspicuous nature_. Is a potential concern for device manufacturers. For instance, some manufacturers have the perception that the bond line.-niay contribute to the formation of und sired particles during sputtering; if generated, there is a belief that such particles potentially might affect performanc of resulting devices. U.S. Patent No. 4,594,219 (Hostafier at at) addresses side~by-side consolidation: of preforms to form complex or compound shaped articles (e.g., connecting rods and hand wrenches). Consolidation (e.g.. by hot isosiatic pressing) of molybdenum and/or titanium powder containing preforms is not described. Moreover, particular processing steps to achieve successful result in the consolidation of molybdenum and/or titanium powder containing preforms is also not described,

07 U S, Patent Application No. 20050191202 (iwasaki ef al) discloses a molybdenum sputtering target (in which an examp!e is provided of a 70.0 at% Mo-3p.p at/% Ti material). The application discloses a requirement for use of relatively high temperatures and pressures, stating at paragraph 40 that if a. pressure below 100 fvlPa and a temperature below 1000°C Is used, "It is hard to produce the sintered body haying a relative densit of not less than 98%", The application describes process by which a relatively large sfee body is consolidated from secondary powders and then the sintered body is cut into separat targets, One example illustrates a further hot plastic working step.

0Q|] ϋ .8 , Patent Application Publication 20050189401 (Sut er) discloses a method of making a large Mo billet or bar for a sputtering target wherein two or more bodies comprising M ar placed adjacent one another (e.g. stacked one on the other) with Mo_. powder metal present at gaps or joints between the adjacent bodies. The adjacent bodies are hot isostatica!ly pressed to form a diffusion bond at each of the rneial-fo-Mo powder iayer o~metai joint between adjacent bodies to form a billet or bar that ca be machined or otherwise formed to provide a large ^'sputtering target This patent publication appears to disclose bonding of major side surfaces, not edge-to-edg bonding of plates.

|O0S] U.S. Patent Application No 20060218602 (Zimmerman et at) describes another method for making large area sputtering targets with a olybdenurr>titanium composition , which includes a cold spray deposition step for joining a plurality of targets at an interface. Though acknowledging certain electron beam welding and hot isostatic pressing processes to join targets, in paragraphs 165-166 (referring to Figs, 17 and 18)., the patent application indicates that electron beam welding results in porosity; and the hot isostatic pressing results in a brittle alloy phase.

I001QJ U.S. Patent Application Ho. 20070251820 {Nitta et a!) describes an example of soother^' approach to the manufacture of a moiybdenusTi-titanium sputtering target, in this publication, diffusion Joining (at a temperature of at least 10GG°C) of two -or mo previously sintered or melted sputter targets along at least one side is addressed. The use of aTA Ti powder in the joint is described.

[0011 j U.S. Patent Application Mo. 20070289884 (Zhifei et a!) identifies a need in large area sputtering targets to f ill gaps between multiple target sections carried o a common backing plate. Th patent illustrates the material deposition processes between adjoining target portions. Interestingly, the patent recognizes that the manufacture of larg molybdenum piate targets poses difficulties, and the need for efficient manufacturing,

[00 2| Cold spray technology is an approach t ai as been employed to deposit, a powder materia! onto a substrate in the absence of heating the powder materials. The use of cold spray processes in the field of sputtering targets is Illustrated in United States Patent Application Nos. 20080216802; 20100086800; 20110303535; and United States Patent No, 7,0 0,051 , all incorporated by reference herein for ait purposes.

£0813] The formation of -multi -component large scale sputtering targets that include molybdenum and at least one additional alloying element is taught in commonly owned United States Provisional Application Serial No, 81/484,450 filed on May 10, 2011 , and 13/487.323 filed on ¾ay 9,2012, and also PCT Publication No. WO 2012/15481?, eac incorporated by reference herein for all purposes.

[001 ] In view of the above, there remains a need in the art for alternative sputtering targets (especially large size targets, such as targets exceeding about 0,5 meters, about 1 meter, or even about 2 meters for its largest dimension) _f and approaches to their manufacture that meet on or any combination of the needs for genera! uniformity of composition, general uniformity of micro-structure, insubstantial likelihood of particle formation, or relatively high strength (e.g., relatively high/transverse rupture strength), Moreover, there remains a need in the art for alternative sputtering targets that avoid the need for powder during any final hot Isostatic pressing process. For instance, it may be desirable that my added material that will become part of a joint between adjoining blocks is a generally solid and cohesive mass of material prior to a final consolidation (e.g., fe a heft isostatio pressing operation). The ability to minimize any visible Joint lines or other visible variations in continuity of structure, though not critical for present purposes, may also be desirable attribute.

SUM ARY Of THE VENTi H

100153 In one aspect, the present teachings meet one or more of the above needs by providing a sputtering target, which may in particular be a relatively large sputtering target (e.g., exceeding about 0.5 meters, about 1 meter, or even about 2 meters for its largest dimension; or stated_, in another way, exceeding about 0.3 square meters Cm²)_.. 0,5 m^i;, 1 rn\ or e en 2 m^a for the target sputtering surface available for sputtering), comprising at least two consolidated blocks, each block including an alloy including a first metal (e.g., a refractory metal such as molybdenum, whic may he present in an amount greater than about 30 percent by weight) and at feast one additional alloying element: at least ^'one continuous solid interface portion; and a joint between the at feast two consolidated blocks, which joins the blocks together to define a target body. The joint may include at feast one continuous solid interface portion (which desirably may be a -generally coherent metallic mass, such as one that Is formed in situ from a partieuiated starting material (e.g., such as by cold spray deposition of a etallic powder mixture), one that is formed in a separate densificalion operation (e.g., compacting, sintering or both), or both). Desirably, the sputtering targe along the joint will also exhibit a transverse rupture strength per AST!vi Β528-Ί0, of at least about 400 f¾.

|00103 in another aspect, the teachings herein meet one or more Of the above needs by providing a method for maki g a sputtering target comprising the steps of providing first and second at least partially consolidated powder metal biscks each optionally having a prepared surface, and each including an alloy including a first metal (e.g., a refractory metal such as molybdenum, which may he present in an amount greater than about 30 percent by weight), and at least one additional alloying element: interposing between the consolidated powder metal blocks at least one continuous solid interface portio (e.g., before a final consolidating step); contacting ^'the prepared surface of the first block indirectly with the prepared surface of the second block via the at least one continuous solid interface portion in the substantial absence of any .bonding agent between the contacted surfaces to form a contacted joint structure; isostatically pressing the contacted structure at a temperature (e.g., one that is less than about 108O^eC), at a pressure and for a time sufficient to realize a consolidated joint between the first and second blocks. |0017J The continuous solid interface portion may be formed n the absence of applying po der between blocks prior to a joining step; namely the steps of - manufacture would avoid any loose powder between blocks to accomplish diffusion bonding during a hot isosiatlc pressing ste that results in the formation of a target body, such as a large scale target body, -which includes the blocks, The continuous solid interface portion may be formed by employing a step selected from (a) cold spraying a metal powder onto at ieasi one of the blocks or forming the at least one continuous solid interface portion (e.g., along a side edge of one or more blocks); (b) compacting a body of metal- powder (e.g., a metal powder admixture} to form the at least one continuous solid interface portion (which Is thereafter interposed between blocks}; _. (c) sintering -a body of a metal powder mixture to form the at least one continuous solid interface portion (whic is thereafter interposed between blocks); (d) cold spray ing a metal powder into a d ie for forming the at least one continuous ^'.solid interface portion; fe) cold spraying a metal powder onto a substrate to form the at least one continuous sold interface portion thai may optionally include, but preferably omits, the substrate; or |f) an combination of fa) through (e). The continuous so!id interface portion thus may be the result o employing a cohesive mass that is formed In situ with metal powder blocks (e.g., by a cold spraying operation) or is formed a a preform (e.g., a tile that is compacted, sintered, and/or cold sprayed, and Is- thereafter interposed between blacks). Though the cohesive mass is contemplated to have some porosity, desirably the average see of any pores is sufficiently small and the pores are substantially u niformly distributed so that voids would not result In irregular shrinkage in a consolidated joint following a final consolidating step to make a large area target.

0O1SJ in general, when a mixtur Of molybdenum and tftanium is employed t make the continuous solid interface portion, conditions may be employed so that prior to arty final consolidating step, the amount of uncombmed titanium remains generally high. For example, the amount of starting titanium ^' powder in the mixture that remains unalloyed prior to a final consolidating step to form a resulting tar et is at least 50%, 60%, 70%, 80%, 90% or more by weight of the total titanium in the mixture. Thus the step of forming any continuous soiid interface portion precursor (e g. , a cold sprayed mass, tile, a sintered body- or any combination thereof) may be done at. a temperature below the melting point of titanium. If steps are performed above the melting point of titanium in the mixture, then they ar performed for a time sufficient for avoiding aiioy formation with other metals in the mixture by which less than about 50%, 40%, 30%,, 20%, or even 10% by weight, of the starting titanium in the powder mixture becomes alloyed with another metal in the powder mixture:

1001 ø] The target bodies in accordance with the teachings herein may have a

Vickers Hardness (HVN) per ASTM £384-06 of a! least about 280, about 275 or even about

S 300; for example, it may have an HVN of about 260 to about 325, The target, the target body, the alloy, one or more consolidated blocks, or any combination thereof may include molybdenum in an amount greater than about 30 weight percent. The target, the target ^'Body, the alloy, one or more consolidated blocks, or any combination thereof may include roo brJe.num in an amount greater than about 30 atomic percent, The target, the target body, the alloy, the consolidated blocks, or any combination thereof preferably may include ^■molybdenum in an amount greater than about 30 volume percent. Th target body may have a density of at least about 0,92, 0.95 or even 0.98 times the theoretical density of the overall material per ASTM B31.1-08. For one illustrative target that consists essentially of molybdenum and titanium, the target body may have a density in the range of about 7.12 to about 7,30, and more specifically about 7,20 to about 7,25 g cn . The .sputtering target body may also be sufficiently strong so that it withstands, without fracture, routine stresses encountered during subsequent assembly operations (e.g., a three point straightening assembly operation, a creep flattening operation, or some other operation during which the target body and any Joint may be subjected to load of greater than about 0.6 MPa}.

P020J in yet another aspec of the teachings herein , if is contemplated that sputtering is performed using a sputtering target in accordance with the present teachings. It also is contemplated that thin films result that are used in any of a number of electronic devices {e.g., as a barrier layer, an electrod layer or both), such as one or more of a television, a video display, a smartphone, a tablet computer, a personal digital assistant, a navigation device, a sensor a portable entertainment device (e.g. , video players, music players, etc), or even a photovoltaic device. The thin films may .have a reduced amount of structural artifacts attributable to particles as compared wit sputtering using targets made with powder josnts.

DESCRifTSON OF THE D AWLS

[0021] Fig 1 is an illustration of a cold spray joint preparation.

|0023¾ Fig, 2 is an illustration a cold spray formation of a tile.

10023} Fig. 3 is a exploded perspective view of a biock-tiie-block structure.

[00241 Fig. 4 i an illustrative scanning electro microscope hackscatter photomicrograph a SOOx for illustrating phase amounts that may be expected In a hot isostaiicaiiy pressed target made from a mixture of SO af% molybdenum. nd 50 at% titanium powders. DETAILED DESCRIPTION

|0S25) Turning now in more detail to particular teachi gs of t e present invention, in general, the present teachings envision a relatively large sputtering target, and particularly sputtering target consolidated from metal powder, w e ein the target is made fay Joining multiple blocks In the absence of a powder interface. The targei generally wii! include a target body (namely, the consolidated portion of the target, and specifically th portion of the overall target assembly that is subjected to bombardment for purposes of matehai removal and sputter deposition) thai may be joined to a backing plate in any suitable art disclosed manner. The sputtering target bod may be any suitable geometry. It may be generally circular (so that it would baye a diameter as s largest dimension), it may be rectangular, and thus hav one of its side edges as having its largest dimension (e.g. , the length of the side edge). It may be tubular. Though the teachings herein also apply to smaller sputtering targets, they have particular utility for larger scale targets. By way of example, larger scale target bodies may be steed such that they exceed about 0.5 meters, about 1 meter, or even about meters for its largest dimension. Examples of such target bodies may be generally rectangular targets having a length i ®t exceeds about 0.S meters, about 1 meter, or even about 2 meters. Such target bodies may have a width that exceeds about 0.5 meters, about 1 meter, or even about 2 meters. The resulting target bodies may exceed about 0.3 square meters (rh²), 0.5 m\ 1 n , or even 2 m^s for the target sputtering surface available for sputtering.

I0G2SJ The target body is typically made to Include at least two consolidated preformed blocks, and a consolidated Joint portion, which preferably may be a continuous solid interlace portion, therebetween. The consolidated blocks-Will typically be sized (©;¾,, length, width, area, or any combination thereof) to be smaller than the overall resulting target body. For example, they may be about one half (or smaller) the ize {e.g., length, width, Or area) of the desired resulting target body (e.g.-, they may be about 1 n the size- of the desired resulting target body, wherein n refers to the total number o? consolidated blocks employed to make^' the^' target ^'body, ^"exclusive of any intermediate ^'tiles as described herein). Each of the consolidated blocks may each be approximately the same size as each other block. One or more consolidated block may be smaller than another othe blocks. The blocks may be of generally the same shape as each other, or they may differ as to shape. The blocks may have a generally rectangular: prism shape. The blocks may be generally cylindrical. The blocks may include one or more channels, through holes or other openings Fo example, the blocks may be generally cylindrical and have a through passage for defining a tubular shaped block. One or more side walls of the block may be generally orthogonally oriented relative to a surface that will function as a sputtering surface, One or more side walls, of the, block m y be general y Oriented at a slope angle of at least ± 5". 0*^20^* or more relative to a plane-that would be perpendicular to a sputtering surface, in this manner it is possible thai a joint may employ a scarf joint between adjoining blocks. Other joint .structures other than a butt joint or a scarf joint may be employed, such as a lap joint, dovetail joint, or any

combination of the above joints,

[002?! More particularly, a plurality of blocks are pre aid by consolidating^' powdered metal. The consolidation may occur from sintering, cold isostatic pressing, hot isosfatic pressing, otherwise compacting (e.g , rolling, die compacting or both) or any combination thereof. For example, one approach is to first compact to about SO to about 85% of theoretical density, such as by eoid isostaiScaiiy pressing a mass of powder of the desired composition (such as is taught in U.S. Patent Application No. 2.0070080884 at paragraph 50 through 53, incorporated herein by reference (Gaydos et al)). The resulting compacted forms may be machined to form block precursor structures. The blocks (or block precursor structures) m y be further densified such as by hot isostaticaily pressing to form blocks that will be joined with others to form a target body, ft is contemplated that the powdered metal, before consolidation, will include one or more powders of a substantiall pure metal (e.g., having a purity (defined to mean free of metallic elements) of at least aboui 99.5%, ¾9.95% or even 99,995% purity).

[0028] The powders, before consolidation, will typically have an average particle size of less than about 59 pm, or even less than about 35 pm_; as meas red according to AST 8822-10. For example molybdenum- powders, before consolidation will typically have an average particle size of less than about 25 prn, o even less than about 5 pm, as measured according to ASTfv? 8822-10! When titanium is employed, the titanium powders may have an average particle size of less than about SO pm, or even less than about 35 pm, The titanium powders may have an average particle $fe© of higher than about S pm.. or eve higher than about 25 pm.

[0029] Prior to consolidation, powders may be blended- in accordance with art disclosed powder blending techniques. For example, mixing may occur by placing the molybdenum and titanium powders in a dry container and rotating the container about its central axis, Mixing is continued for a period of time sufficient to result in a completely blended and uniformly distributed powder. A ball miii or simila apparatus (e.g.,. rotating cylindrical, rotating cone, double cone, twin shell, double planetary, and/or sigma-biade blender) may also be used to accomplish, the blending step. As discussed herein, and unless otherwise stated, references to metal powders ^'include powders of one metal or a combination of two or more metals, (0930J The composition in each block of the resulting target bod will generally include ol bdenu and M least one additional alloying element- For exam le, the composition may include an alloy including molybdenum in an amount so that in the resulting tergal body there is a: substantially pure phase of mol bde um present in an amount greater than about 30-vo!%_< greater than about 35 v6!%, or even greater than about 40 v;oi of the resulting target body, and at least one additional alloying ingredient. The composition may include an alloy including molybdenum in an amount so that in the resulting target body them is a substantially pure phase f molybdenum present in an amount less than about 48 percent by weight, or even less than about 45 percent by weight (e.g. , about 43 percent by weight) of the overall block, and at least one additional alloying ingredient. The amount of the molybdenum in the target, the alloy, or both, may range from about S to^' about 95 at%, more preferably about 20 to about 00 at%, still more preferably about 30 to about 70 at%. it may be about 40 to about 80 at% (e,g„ about SO af%). The remaining alloying elements may make up the balance, For example, the amount of titanium in a system employing only molybdenum and th additional alloying element powder may be about 1 GO at% minus the amount (in at%) of molybdenum. Thus, as can be seen frcn the above, the teachings contemplate a composition of the target, the alloy, or both, of about 30 to about 70 at% Mo and ti e balance being the at least one additional alloying element such as titanium (e.g., about 50 at% Mo and about SO at of another element (such as titanium}}.

I0Q31J In general, when a mixture of molybdenum and titanium is employed t make the continuous solid interface portion, conditions may.be employed so that prior to any final consolidating step_., the amount of uneo bined titanium for use: as -a. continuous solid interface to define the consolidated joint portion remains generally High. For example, the amount of starting titanium powder in the mixture that remains unalloyed prior to a final consolidating step to form a resulting target is at least 50%, 60%, 70%, 80%, S0% or more by weight of the total titanium, in the mixture. Thus, the step of forming art continuous solid interface portion precursor (e.g., a cold sprayed mass, a tile, a sintered body or any combination thereof) may be done at a temperature below the melting point of titanium. If steps are performed above the melting point of titanium in the mixture, then they are performed for a time sufficient for avoiding alloy formation with other metals- i the mixture by which less than about 50%, 40%, 30%, 20%, or even 10% by weight of the starting titanium In the powder mixture becomes alloyed wit another metal in the powder mixture.

|0032| The at least one additional alloying element may be a metallic ^'element, sao si one selected from titanium., chromium, niobium, zirconium, ..tantalum, tungsten or any combination thereof. If is possible that the at feast one additional ailoying element . may includ hafnium and/or vanadium, it is also possible that the at feast one additional alloying element may -include one or more alkali metal (e.g., lithium, sodium and/or potassium in an amount of less than about 10 at% or even 5 at% of th festal composition). Examples of suitable alloying ingredients are disclosed In PCI Application Wo, WO20O 134771 , and U.S. Application Serial N ¾ US 12/990,084; 12/827,SS0 andl 2/827,662 (ail incorporated by reference). The amount of the at least one additional alloying ingredient may be such that it will result in (I) a substantially pure phase of that alioy ing element; and/or (si) an alloy phase thai includes molybdenum and the at least one alloying^' element. S^'y-way of example, the amount of the at least one additional alloying leme t may be sufficient to obtain a substantially pure phase of the at least one additional alloying element that is at teas! about 2, 4 or even about 6 voi% of the resulting target body . The amount of the at least on additional alloying element ma be sufficient to obtain a substantially pure phase of e at least one additional alloying element t at Is less than about 25 voi%, 15 yol% or even about 10 v©! of the resulting target (e.g., the resulting target body).

[0033] The amount of each of the moly bdenum and the at least one additional alloying element may be sufficient to realize in the resulting target body an alloy phase (i.e., one that includes both molybdenum and the at least one additiona alloying element) In an amount greater than about 30 vei%, 40 vol%, 44 vo!% or even about 48 voi%. For example, the alloy may be present a a major constituent of the block, by volume. The amount of each of the molybdenum and the at least one additional alloying element may be sufficient to realize, in the resulting target body an alloy phase that includes both molybdenum and the at least one additional alloying element i a amount less than about 70 vol%, 60■«©!%, 56 voi% or even about 5.2 vol%. As can be seen, the alloy phase may be present as a major constituent^' of ^'the block, by- volume_*

[0034] The resulting target body may be further characterised by at least one, preferably combination. f at Ieast two features, more preferably a combination of at least three features, still more preferably a combination of at least four features, and even still more preferably a combination of ail features selected from the following^' features fi} through (v)^*.. ^'(i) at ieast one joint between at ieast two consolidated blocks (e.g., side--by-s^'ide or and- to-end adjoining blocks) that is free of irsicrostructure derived from diffusion bonding an added loose powder bonding agent; (it) at least one joint between at feast two consolidated blocks {e.g., side-by-side {such as face-to-faee) or end-to-end adjoining blocks); (Hi) a sputtering target body that Is at least about 0.5 meters, about 1 meter, or even about 2 meters, along its largest dimension, and which exhibits a transverse rupture strength per ASTM 8528*10 that is generally uniform {e.g., the fluctuation from Sow to high is less than about 50% the highest value, or even iess than about 35% of the highest value) throughout the body, including across ^: the joint, and/or which may be at least about 400 MPa, W0 Pa, 800 VlPa, 700 ivtFa, SOOMFa or even 00MP ; Civ) the target body exhibits a View rs Hardness (HVN) of at least about 260, about 2:75 or even about 300 (e.g-, it -ma have an HVN of about 280 to about 325); or (v) the target body may have a density of at least about 0.92, about 0.85 or even about 0.98 times { e theoretics! density of the overall material (e.g.. for a target body that consists essentially of molybdenum and titanium, the target body may have a density in the range of about 7.12 to about 7.30, and more specifically about 7.20 to about 7.25 g/cm³). The sputtering target body ma also be sufficiently -strong so that it withstands, without fracture, routine stresses encountered during subsequent assembly operations (e.g., a three point straightening assembly operation, a cree flattening operation, or some other operation) during which the target body and any joint may be subjected to a load of greater than about 0.8 MP&. Methods herein thus may include one or raore steps of performing an assembly operation {e.g., an assembly operation selected from a three point straig tening operation, a^' creep flattening operation, or both). As discussed previously,, another aspec of the present teachings, which is believed to result in sputter target bodies that exhibit one or more of the features discussed previously in this paragraph pertains to methods for making a sputtering target. Broadly stated, the methods include steps of consolidating at least two ^"blocks into preforms, and joining the blocks together. The joining of the blocks is desirably done under heat and pressure, and in a manner thai otherwise avoid the need for reliance upon an intermediate powder bonding agent between opposing surfaces of the blocks as a primary mode of assuring a bond between the blocks.

|GG3§3 Desirably, the bonding of adjoining blocks relies mainly upon the formation of at least some metallic bonds (with some mechanical bonding being possible as well) between metal from opposing cold-sprayed surfaces of the blocks, opposing surfaces of a block and a preform tile (e g,, a previously sintered and/or a die-compacted file, which itself may be formed by cold-spraying, -may include a cold sprayed surface, or both), or any combination of the above,

£00361 Accordingly, one approach Involves a step of making a plurality of consolidated blocks as preforms. The preforms may have substantially the same composition as each other. The preforms may be made in a substantially identical manner as each other. The preforms may be consolidated in any suitable manner The blocks of the preforms may be any suitable geometry. For example, they may be generally rectangular prisms. They m y be generally cylindrical. They may be hollow (e.g., tubular). Other shapes are also possible,

|0037} Typically the manufacture of the blocks will emplo a powder starting material. The powder may be densified by the application for a desired period of time of heat, pressure or both For example, they may be compacted, sintered, cold isostaticaii pressed, hot isostaticail pressed or any combination thereof. An initial compaction step may occur, for example, an initial step ma be employed to compact a mass of powder to about 50 to about 85% of theoretical density e.g. , about 60 to about 70% of theoretical density'). This may be done by a suitable cold isostatic ress ng operation. One or more secondary operations may also bo performed, such as a cold working step, a ot working step or otherwise.

[0038] A preferred approach ^'to consolidation inc udes a step of hot: isostatically pressing (HIP) a mass (e.g., an unc mpleted -powder mass or a compacted powder mass) at ^'.pressure of at least- about lOO Pa, for e¾ampte, with molybdenum-containing materials (as well as others) , the HiP process desirably may be performed at a temperature below about 1 Q80°C (e.g... at about 1050¾}_; 100Q°C, @S0¾, 900^¾C, or even beiow about 850°C (e.g;, at about 525^£iC)> The HiP process ma range in duration from about 1 to about 12 hours, and more preferably about 4 or 6 to about 10 hours (e.g., about 8 hours). By way of example, without limitation, the. mass may be pressed to generally ^' rectangular blocks -having a thickness of about 10 mm to about 60 mm, and more preferably about^' 15. mm to -about 46 mm (e.g., about 15 mm, about 25 mm, about 3S mm or even about 45 mm). The mass ma be pressed into s _.generally rectangular block having a width of about 25 to about 1-00 mm (e.g. , about 30 mm, about 50 mm or even about SO mm), and more preferably from about 30 mm to about 50. mm. The mass may be pressed into a generally rectangular block having a length of about 70 mm to about 160 mm, and more preferably about 90 mm to about 150 rn (e.g., about 90 mm. about 20 mm, or even about 50 mm).

[0039] Two, three, or more blocks are joined to form a target body. As mentioned, preferably this is done in without employing a loose powder bonding agent as the primary means of Joining. For example, though some amounts of a bonding agent ma be employed, aspects of the present teachings -contemplate that the joining, to ^'ma&e the target body, may be achieved in the absenc of any bonding agent (e.g., absence of any loose powder bonding agent)* By way of illustration, two blocks may be prepared, each having dimension of about 1.5 meters long by about 0,9 meters wide by about 0.18 meters thick. They may be joined together along opposing width edges (e.g., with a continuous solid iriierface portion therebetween) to form a target body. In another illustration, two blocks may be prepared, each having dimensions of about 1.2 meters long by about 0.5 -meters wide by about 0.46 meters thick. They are joined together along opposing length edges to form a targe! body, in sti anoiher illustration, two blocks may be prepared, each having dimensions of about 1.2 meters long by about 0.5 meters wide by about 0,3 meters thick. T hey are joined together, with at least on continuous solid interface portion therebetween, along opposing lengt edges to "form a target body, in still yet another illustration, three blocks may be prepared , each having dimensions of about 0,9 meters long by about 0.3 meters wide by about 0.25 meters thick. They are joined togethe along opposing length edges with at least one -continuous solid interface portion therebetween, to form a target body. Mo e than three biocks can be employed, such as an array of two or more blocks along two or more axes. 0040] Following the pressing, but prior to the joining of the preform blocks to form a sputter target body_... one or more surfaces of the preform blocks may be surface prepared (e,g„ surface roughened and/or polished, whether chemically, mechanically,

.steetrochemfcalJy. a combination thereof or -otherwise) to-impart a desired surface finish, such as for increasing surf ace area of the surface for contacting an adjoining block as compared with a surface that is not surface prepared, or for otherwise increasing contact area between two- or more adjoining blocks. For example, surfaces t at are to oppose eac other when joined desirably ar prepared, (e.g., roughened). They may b prepared so as to achieve an arithmetic average surface roughness (as measured by ASTM 8946-06) that may be at least about SO μ-irs (1.3 p.rn)_> or even at least about 100 μ-Ιη (2.8 pm).{e.g.,:¾bQu! 12-0 μ··Ιη (3 p ) to about 150 μ-in (3-, 8 pm}}. They may be prepared so as to achieve an arithmetic average surface roughness R_A (as ^'measured by ASTM 894$- 06) that may be less than about 200 μ-ιη (5.1 pm), less than at least about 180 μ-Ιη (4.8 μηι), or even less than about 150 p~in (3.8 pm), or even less than about 120 μ-in (3 pm). For example, the arithmetic average surface roughness R_A (as measured by ASTM B946-Q8) may range from about SO μ-in (13 pm) to about 150 p~ln (3.8 pm)), and more specifically about 63 μ-ίπ (1.8 pm) to about 126 μ-Ιη (about 3.2 pmj.

£0041] One possible approach to achieving a desired surface finish is to cold- spray deposit powders onto at least one surface of a consolidated l ck to the desired roughness. This may be done with or without a step of surface roughening prior to the cold spray deposition. It is contemplated that any step of cold spraying may include depositing a mixture of powders of .at least two different unalloyed metals onto a side of at least one of the consolidated blocks to define the afieasi one continuous solid interface portion for causing the powders to^' mechanically- .attach to the block, while gene ally avoiding the presence of loose powders. Illustrative cold spray teachings can be found in United States Patent Application Nos, 20080216802; 20100086800; 20110303535; and United States Patent No. 7910051 , all incorporated by reference herein for all purposes, i general, a suitable device having a o zl (e.g., a cold spray gun) ejects a powder mixture jet at

Supersonic speed to direct the powder mixture onto a surface. It will be. appreciated thai "cold spray" does not exclude other kinetic spray systems. The term cold spray is used throughout the teachings herein. However, it is understood that it is possible to use a kinetic spray process as well

|0042| A gas jet flowing at supersonic speed is imparted upon a mass of powder,, which may have a particle si e of 0.5 to 150 pm. For example, a sufficient gas flow is applied to Kelp ensure a velocity of the powder in the resulting gas powder mixture of 300- to 2,000 m/s, preferably 300 to 1,200 m s. The mixiure Is directed on to the surface of an object. On the surface of the object, the impinging metal powder particles form a layer, the particles ecoming severely deformed, but preferably are not melted. The powder particles are advantageously present in the jet io an amount which ensures a flow rate density of the particles of from 0.01 to 200 an², preferably 0.01 to 100 g/s cm*, very preferably 0.01 g s cm^s to 20 g/s cm², or most preferred from 0,05 g/s cm^2' to^' 17^' g s m³,

[0043} After an surface preparation (e.g., surface roughening, cleaning such as by a step of detergent cleaning, or both) , at^■ least ό » surface of a first block Is contacted, in the absence of any intermediat loose powder, with at least one surface of a second bieck to form a contacted joint structure. The contacting may be direst, .such as by contacting opposing cold-sprayed surfaces of a plurality of blocks. Th contacting may be indirect, such: as via an interface preforra as described herein (e.g., a tile having a side surface that has generally the same dimensions as the block-surface to which it wilt be contacting, and having a thickness of at feast about 2 mm, 4 mm or even 6 mm), The thickness may be about 20 mm or less, or even about 10 mm or less. The preform itself ma include a cold sprayed side surface for contacting.

÷ | When a oo!d sprayed powder layer is deposited onto a surface of a block, an interface preform (e.g., a tile), or both, the average thickness of the layer may be greater than about 1, 2, ^'5, 10, SO, 100 μηι or larger; the cold sprayed powder layer may_.be

deposited to have an average thickness -of the layer of less than about 1 cm, 1 mm, 500 prn, or 200 pm,

I004S| The interface preform (e.g.., tile) may be made by a process capable of achieving a density of the preform of at least about 60% theoretical, 70% theoretical or evert 80% theoretical. By way- of example, conditions ma be such {e.g., sufficient pressure may be applied to the powder during compaction) to define the Interface preform as a tile having a density of about 85% to about -85% of theoretical density throughout the life, and more specifically about 75% to about 85% of theoretical density. The ^'interface preform (e.g.. file) may have a thickness of about 2 to about 10 mm (e,g., about 3 to about 7 mm, or more specifically about 4 to about 5 mm). Larger or smaller thicknesses are also contemplated. 0046} Though cold isostatic pressing is .one possibility, surprisingly, die- compacting a powder mixture is believed to yield excellent results as well, it is also- ossible that a powder mixture can be cold-sprayed info a cavit of a die or other suitable too! to define a preform having the general complementary shape of the tool cavity. As to the latter it is possible that prior to deposition, the fool is contacted with a suitable low f notion coating to aid in removal of the preform in later steps. The interfac preform may he configured with one or more projections or other structural feature to allow gripping for removal. The -tool may be configured with one or more devices for ejecting the part from the cavity,

{0047] On¾ approach is to make an interface preform such as a tile by die compacting a mixture of two or more high purity (e.g., at least §8,5% pure, in relatio to metallic impurities metal powders, A suitable pressure is applied (e.g.. at about worn temperature, and optionally at- an elevated temperature}, for a suitable time to achieve-- near net shape green compact that has a density of at least about 60, 70 or 80 of theoretical density (e.g., to about 60% to about 85% of theoretical density). By way o example, a pressure of at- least about 60 ksi, 70 fesf or 80 ksi (e g.,, on the order of about 12S0 tons over about 30 square inches) may be employed. A pressure of less than about 200ksl, 150kS! or 100 ksi may be employed The pressure may be applied for a time of at least 10 seconds, 15 seconds, 20 seconds or 30 seconds. The pressure may be employed for a time of less than 5 minutes, less than 3 minutes or even iess than one minute.

£0048| Another possible approach to making an interface preform may employ steps that result in loosely sintered preform, such as a tile. That is, sintering may be employed at a temperature and time sufficient for a mass of metal powder to density sufficiently so that a cohesive and self-supporting mass is formed that can be readily handled and is free of loose powder. The preform may b made by mixing a mass of ^: metal powder (which may include powders of one, two or more metals). A binder ma be included within the resulting mixture, The mass of powder with the binder may b spread to a generally uniform thickness and sintered, The selection of the binder and the temperature and times of sintering may be such that, during sintering, the binder is consumed and results in a certain amount of porosity. For example, a polymeric binder may be employed.

Sintering may be employed at a temperature and time sufficient for the mass of metal powder to realize at least about 50%, 60%, 70%, or even 80% of theoretical density.

Sintering may be employed at a temperature and time sufficient for the mass of metal powder to density to iess than about 95%, 90% or even 85% theoretical density. The sintering may be performed under evacuated conditions. The sintering may be performed u der an inert atmosphere or under a reducing atmosphere. The sintering atmosphere may be fre of hydrogen,

10049} Another approach is to make an interface preform such as a tile by cold spraying a powder mixture onto both sides of a thin sheet that includes molybdenum and at least one other element (e.g., Ti). The cold sprayed powder layer may be deposited to have an average thickness of the layer of less than about 1 cm, 1- mm, 500 pm, or 200 psn, {¾0§0} it is also possible to cold spray a powder mixture onto a sacrificial or disposable substrate (e.g., brass sheet, zinc sheet; or gaivanfeed steel sheet) to make art interface preform such as a tile, instead of preparing the substrate as Is typically done using such methods as a grit blasting sfep, it Is also possible to prepare the substrate with a detergent cleaning step to avoid embedding ceramic grit particles iff the substrate surface. Detergents based on dipropyiene glycol methyl ether may be employed to clean th substrate, followed by a wate rinse with distilled deionfeed water ntil the surface passes the "Standard Test et od for Hydrophobic Surface Films fay the Wafer-Break Test," per ASTM F22~02(20Q?>, Following the detergent cleaning step, the substrate can be cold sprayed in successive layers, preferably of greater than about 50 pm and less than about 250 pm per pass, to build a cold spray deposit with a prefera le' total thickness of greater than about 1,5 iw and less than about 2 mm. Each _.pass may be performed under the same or varied conditions. Preferably., the first pass may be performed at high density conditions to achieve greater adhesion (e.g., increased gas velocity and increased pressure from the nozzle through which the metal powder mixture Is emitted), To achieve less than Mi density on successive passes, the gas velocity can be reduced. Following the cold spray application, a relatively smooth surface of the deposit is desired; however, some porosity .is. also ^'desirable throughout the body of the cole! spray deposit to allow for creep or movement during the hot isostatic pressing process. Porosit ma b achieved by varying the velocity of the stream of the metal powder mixture through the no zle during the cold spray process by controlling the temperature and gas pressure. The cold spray deposit surface may have a certain amount of porosity, which may he generally uniform throughout. For example, the porosity may range from about 5 to about 25% by volume (e.g., about ίδ%) as measured by ASTfvl 896.2-08, The resulting exposed cold spray deposit surface may also have a surface topography that Includes a generally uniform distribution of peaks and valleys., such as a topography by which there is between; about 25 pm and SO pm from peak to valley,

|0051] Processing to form the interface preform (e.g., file} may be under suitabie conditions for avoiding shrinkage of the preform during subsequent steps. That is, for instance, the continuous solid interface portion thus may be the result of employing a cohesive mass that is formed in situ with metal powder blocks (e.g., by a cold spraying operation) -or is..^'formed -as perform (e.g., a tiie that is compacted, sintered, and/or cold sprayed). Though the cohesive mass Is contemplated to have some porosity, desirably the average size of any pores is sufficiently small and the pores are substantially uniforml distributed so that voids would not result In irregular shrinkage in a^■consolidated Joint following a final consolidating step to make a large area target

[0QS2] The blocks may be contacted along their respective side edges (e.g.. at least partially along a length or a width of each block). It also may be possible to stack two or more blocks. The contacted blocks are encapsulated in a pressing vessel, such as a suitable hoi isostatic pressing container (e.g.. a mild steei can that is hermetically sealed for pressing). They are then hot isos afea!ly pressed to a desired shape at a temperatur that is less tha about 1100 or 1000°C (e.g , for molybdenum-containing materials and others) and at a pressure and for a time^■sufficient to realize a consolidated Joint between the first and second blocks. A preferred approach may include a step of hot Isostaticaiiy pressing a powder mass at a pressure of at least about 75 MPa, or even at least about 100 MPa, A preferred approach ma include a ste of hot isosiatica!iy essing a powder mass at a pressure of less than about 300 Pa, less than about 250 MPa,_: or even less than about 175 Ps. The HIP process desirably may be performed and at a iemperai re below about 108O^Qe (e.g. , about i 05G°C), below about 1.0QQ°C« below about 9S8¾, or even be o about SO0°C (e.g., at about 890*0), As such, the HIP process may be free of a step of heating the owde , the can, or both to a temperature of about 1000^¾C of higher, The HIP process may range in duration from abou 1. to about 6 hours, and more preferably about 3 to about 8 hours (e.g., about 4 hours). After the pressing is completed, the can may be removed. Following the hot tsostaflc pressing process, irregularities within the surface of any cold spray deposits are smoothed out, and there are no detectable pores. Ot er details about pressing operations can be gleaned from U.S. Paten H _* 7,537,929 (iCSaydos et a!) incorporated b reference) (see e.g., the Examples).

[00S3J In yet another aspect of the teachings herein, it is contemplated that sputtering is performed, using a sputtering target In accordance with the present teachings. It also is contemplated that thin films result that are used in any Of a number of electronic devices (e.g., as a barrier layer, and electrode layer or both), such: as one or more of television, a video display, a smartphone, a tablet computer, a personal digital assistant, a navigation device, a sensor, a photovoltaic device, or a portable entertainment device (e.g.. video players, music players, etc).

|0δ§ ϊ The thin films may have a reduced^■■amount of structural artifacts atfributabie to particles as compared with sputtering using targets with powder Joints, and are substantially uniform In structure {e.g,_s greater than about 90%). The thin films may have a thickness of less than about 350 rimy -less than about 225 nm, or even less than about 100 nm. The thin films may have thickness of greater than about 5 nm, or even greater than about 10 nm. For example, the films may have a thickness of about 16 to about 25 nra. The thin film may exhibit a resistivity value of about 70 to about 80, or even about 75 to about 85 pQ:em (using a: four point probe). The thin film ma exhibit a SB adhesio rating, for adhesion io a substrate may of either Corning 1737 glass or amorphous silicon {e.g., amorphous silicon coated glass per ASTM D;33SS-Q2), The thin film preferably exhibits good interfacing capability with copper conductors, such as copper conductive layers in display devices. ΙϋϋΒ } The targets herein may be; made in a process that is free of any hot working step, any forging step, or both. Though the temperatures for hot isostatic pressing preferably are below 110O°C, they may be about 00°C or higher, or even i200¾ or higher.

[O0S81 The teachings herein contemplate that resulting target body materials include at least on pure metallic elemental phase, such as pure Mo {and more preferably at least two pure metallic elemental phases, such as pure Mo and pure Ti), along with at least one alloy phase (e.g., β{Τί, Mo) phase). However, it Is possible that the resulting target body will have substantially no alloy phase, such as a jSCTi, Mo) phase (i.e., about 15% (by volume) or less).

[0057] The miorostructure of resulting target bodies preferably is substantially uniform throughout t e body. In a typical target body that includes molybdenum and at least one other element (e,g„ Ti), the micrdsiructure preferably exhibits a matrix of pure molybdenum, with regions of the other element distributed substantially uniformly throughout the matrix. Regions of the other element phase (e.g., pure titanium phase) are generally equiaxed. Regions of the other element phase (e.g., pure titanium phase): may vary In size substantially uniformly throughout the body. For example, such regions may achieve a largest region diameter on the order of about 200 pm. Regions of the pure element phase (e.g., pure titanium phase) may have an average region diameter of about 50 to about 00pm.

fDOSSJ Bonding of adjoining blocks may take place along a side edge of a block, across a face of a block, or both.

|00S9| With reference to the drawings, Fig. 1 illustrates an example of a block 10, having an upper surface 12 (which may be a sputtering su face- in a finished target) and a side wall 1.4. The side wall 14 is shown having a layer of cold spray deposited powder on if. The powder may be delivered, via an apparatus {not shown) having a ozzle 16 through which a stream 18 of a metal powder mixture is emitted while at a temperature (e.g., about room temperature) below the atmospheric pressure melting temperature of any of the metals of the metal powder mixture. Two or more blocks such as block 10 (each having a layer of cold sprayed powder deposited in it) may thereafter be contacted with each other, encapsulated, and hoi i^'sostaticaiiy pressed as described herein.

f¾0SQ] Fig, 2 illustrates a too! 2Q having a cavity 22 info which a stream 18 of cold spray powder may be introduced to define a part that is generally complementary in shape with the shape of the cavity. In this manner a preform (e.g., a tile) ma be formed that will serve as a continuous solid interface portion between opposing blocks.

f MM1] Fig, 3 illustrates an example of the relative positions of a first block 24, a second block 26 and interface preform (e.g., tile) 28 having opposing joining surfaces 30a and 30b, in an assembly made In accordance with the teachings herein. A can be appreciated in instances when on -or both of the blocks have cold spray deposited surface, such as surface 14 of Fig. 1, the preform may be omitted, it is also possible that the preform may have a cold spray deposited side surface (e.g., joining surfaces 30a and/or 30b of Fig, 3 may have a cold spray deposited surface. The blocks 24 and 28 may be assembled together with the Interface preform between them encapsulated , and hot IsostatScally pressed as described herein. [0082] As to ail of the teachings herein, including those in the following examples, the volume percent of the respective phases are determined by a met od that follows the principles from ASTM standards £582- 11 and El 245-03 (2008). Following this method, an SEfV! backscatter detection (BSE) mode image is taken such that the phases are distinguishable by the intensity of pixels in a black-and-white image. Using 8SE mode, the number of scattered electrons will be directly related to atomic number, so heavier elements will appear brighter. For example, the large difference in atomic number of Mo (42) and Ti (22) makes the identification of each element possible from a . backscatter image. The alloy phase will topically appear gray, with an intensity between brightest pure elemental (e.g., Mo) regions (showing as the most white) and the dark s pure elemental (©,§„ Ti) regions, as illustrated in Figs, 4a and 4b below. By analyzing a pixel intensity histogram (8-bit image; Intensities from 0-255), thresholds can be defined and the area percentage of each phase can be calculated by a pixel count of the Intensity rshggi for each phase. Since the material is believed to be substantially homogeneous with no preferred direction for any phase, the area percentage is treated as being equal to the volume percentage of eaoh phase. For the above analysis, the person skilled In the art will recognize that It is possible that the thresholds may be defined in an objective ^'manner by measuring the minima between peaks in a pixel intensity histogram derived from the BSE image, For example, these minima can be calculated by fitting a 2nd--order polynomial equation to the histogram data at the ^'regions between peaks,

[006.3} By way of illustration, with reference to Fig. 4. there is shown generally an illustrative microstructure that may be expected for a o_^Ti. target bod prepared by hot ssostafic pressing of a metal powder mixture having about 50 at% Mo and 50 at% Ti, in these scanning electron microscope image (in backscatter electron detection mode), the pure titanium phas is the darkest phase, The medium shaded phase essentially surrounding the titanium is a titanium/molybdenum alloy phase (e.g., believed to be a β- phase, but which has varying concentrations of titanium and molybdenum throughout), and the lightest phase i molybdenum. For the ^'embodiment of Fig, 4, there is seen to be a volume percentage of f5~phase of about 55, 7 vol%, about 39.6/ vol% Mo and about 4.7 vol%Ti.

0)064] A seen from the above, an approach: to the formation of large area sputtering targets is provided. The approach is predicated generally upon the avoidance of joining consolidated blocks using (as the primary or main joinder mechanism) diffusion bonding via hot isostatic pressing of a ioose powder between the blocks. The present teabhsngs; envision employing a continuous solid interface portion as an intermediate layer between the blocks. The continuous solid interface portion may be mad by (a) cold spraying at least one metal powder onto at least one of the blocks for forming, the at least one continuous solid interface■^■portion; ^"(b) compacting a body of a metal powder mixture to form the at least one continuous solid interface portion; (c) sintering a body of a metal, powder mixture to form the at least on© continuous solid interface portion; (d) eoi spraying at least o e metal powder into a die for ^'forming the at least one at least one continuous solid interface portion: (e) coid spraying a metal powder onto a substrate to form the at feast one continuous solid interface portion that may optionall include, bu preferably omits, the substrate; or (f) any combination of (a through {e}. St should be appreciated that reference to ^continuous solid interface portion'' does not require that such portion be free of any porosity As th teachings indicate, some porosity is to be expected (e.g., prior to a final hot isostatic pressing operation, the density of any of the described .continuous solid interface portions may be at least about 60%, 70%, 80% or higher). Desirably, during any steps of making the continuous solid interface portion starting powders of two or more, though mixed together, remain unstayed, and may not become alloyed until a subsequent hot isostatic pressing operation:.

D0S5I The ..present teachings are illustrated by reference to sputtering targets that include molybdenum with one or more other elements. The teachings may also be applicable to other materials as well, and are not necessarily limited to molybdenum- containing systems. For example, other refractory metals (e,g>, tungsten, niobium, tantalum or any combination thereof) may be employed in a major amount (at%, vo!% or wf.%) of the target. The present teachings may be employed as an alternative for bonding adjoining blocks thai include two discontinuous phases and/or that heretofore require expiosive bonding techniques. By way of example, without limitation, Ta/Ta~-i5W clad plates may be joined using the techniques herein. Further; though the -te c ings herein are particularly applicable to join consolidated powder metallurgy derived target blocks, they can also be employed to join cast or ingot-derived blocks (e.g,, electron beam melted and

tbermof riecharsiea!iy processed blocks) ,

|0066| One be efit of the teachings herein is believed due to the avoidance of potential issues with segregation, low density, and/or shrinkage, which are often associated with hoi isostatic pressing diffusion bonding with the use of a powder for defining a snfer!aye Without intending to be bound by theory, the conditions taught herein are selected to that there Is an enhanced driving force for atomic transport from the solid interface portion during final consolidation step due to the reduction In surface energy (and perhaps strain energy) to the interface, which In turn helps to enhance bonding. These mechanisms are not believed to exist using other techniques In the published literature, and are believed to result in a consolidated interface portion that is chemically, metaSiurgicaliy, and visually substantially indistinguishable from the bulk material in the blocks, £6Q6?J As to ail of the foregoing genera! teachings, as used herein, unless otherwise stated, the teachings envision ^'that -any member of a genus (list) may be excluded from the genus; and/or any member ot a Markush grouping may be excluded ^"from- the ou i g. Percentages of the sputtering target expressed herein refer to the material of the sputtering target available for sputter deposition, nd do not include other sputter target components, such as basking plates,

£$068| Unless otherwise stated, any numerical values recited herei include all values from the lower value to the upper value in Increments of one unit provided that ther is a separation of at least 2 units between an lower value end any higher value, As an example, if it is stated that the amount of a component, property, or a value of a process variable such as. for example, temperature, pressure, time and the like- is, for example, from 1 to 90, preferably from 2D to 80, more preferably from 30 to 70, It is Intended that intermediate range values such as (for example, 15 to 85, 22 to 88, 43 to 51 , 30 to 32 etc.) are within the teachings of this specification, likewise, individual intermediate values are also within the present teachings. For values which are less than one, one unit is considered to be -0,0901,. 0.001 , 0.0 or 9.1 as appropriate. These are only examples of what is specifically Intended and all possible combinations of numerical values between the lowest valu and the highest value enumerated are to be considered to be expressly stated in this application in a similar manner. As can be seen , the teaching of amounts expressed as "parts by weight" herein also contemplates the same ranges expressed in terms of percent by weight. Thus, an expression in the Detailed Description of a range in terms of at "Y parts by weight of the resulting composition" also contemplates a teaching of ranges of th same recited amount of 'x^K in percent by weight of the resulting composition.

[00881 Unless otherwise stated, ail ranges include both endpoints and all numbers between the endpoints. The use of "about" or "approximately" in connection with a range applies to both ends of the range. Thus, "about 20 to 30" is intended to cover "about 20 to about 30", Inclusive of at least the specified endpoints. Concentrations: of ingredients identified in Tables herein may vary ±10%. or even 20% or more and remain within the teachings.

[0070| The disclosures -of all articles and references, includin patent applications and publications, are incorporated by reference for ail purposes. The term "consisting essentially of to describe a combination shall include the elements, ingredients, components or steps identified:, and such othe elements ingredients, components or steps that do not materially affect the basic and novel characteristics of the- combination. The use of the terms "comprising" or "including" to describe combinations of elements. Ingredients, components or steps herein also contemplates embodiments that consist essentially of, or even consist of the elements, ingredients, components OF steps... Plural, elements^ ingredients, components of steps can be provided by a single integrated element, ingredient, component or step. Alternatively, .® single Integr ted element, ingredient, component or step might be divided into separate plural elements, ingredients, components or steps. The ^'disclosure -df "a" or "one" to describe an clement, ingredient, component or step is not intended to foreclose additional elements, ingredients, components or steps. All references herein to elements or metals belonging to a certain Group refer to the Periodic Table of the Elements published and copyrighted by CRO Press, inc., 1989. Any reference: to the Group or Groups shall be to the Group or Groups as reflected in this Periodic Table df the Elements using the lUPAC system for numbering groups, ft is understood that the above description is intended to be illustrative and not restrictive. Many embodiments as_. well as many applications besides the examples provided will be apparent to those of skill in the art upon reading the above description. The scope of the Invention should, therefore, he determined not with reference to the above description, but should Instead be determined with reference to the appended claims., along with the foil scope of equivalents to which such claims are entitled. The disclosures of aii articles and references,: including patent applications and publications, are incorporated by reference for aii purposes. Tire omission in the following claims^' of any aspect of su bject matter that is disclosed .herein Is dot ^"a disclaimer of such subject matter, nor should if fee regarded that t e Inventors did not consider such subject matter to be pari of the disclosed inventive subject matter.

Claims

CLAS!VSS

What is claimed is;

1) A sputtering target, comprising:

a, at least two consolidated blocks, each block including a refractory metai alloy an amount greater than about 30 percent by weight and at least one additional alloying element;

b, at least one continuous solid interface portion derived from a cold spray

deposition, a sintered preform b d , a compacted powder body or any combination thereof; and

c, a joint between the at least two consolidated blocks, which joins the block together to define target body, the joint including the at least one continuous solid interface portion, wherein the sputtering target along the joint; exhibits a transverse rupture strength per A.STM 8528-10, of at teast about.400 MP .

2} The sputtering target of claim 1 , wherein throughout the target body there is a

substantially Continuous and uniform distribution of three phases.

3} The sputtering target of claim 1 or 2, wherein throughout the target body there is a substantially continuous and uniform distribution of a. substantially pure molybdenum phase, a substantially pure phase of the at least one additional alloying element and a third phase that includes an alloy of molybdenum and the at least one additional •alloying element.

4} The sputtering target of any of claims 1 through 3, wherei the at least one additional alloying element includes titanium,

5) The sputtering target of any of claims 1 through 4, wherein the amount of the

substantially pure molybdenum phase is about 30 to about 80 voi of the sputtering target body,

6) The sputtering target of any of claims through 5, wherein the amount of the

substantially pure molybdenum phase is less than about 48 vol% of the sputtering iai-gei body,

7} Th sputtering target of any of claims 1 through 6, wherein the amount of the

substantially pure phase of the at teast one additional alloying element is about 5 to about 25 vol%.

8) The sputtering^' target of an of claims 1 through 7,^■ wherein the substantially pure phase of the at least one additional alloying element is titanium and is present in an amount less than about 10 voi%.

2S 9) The sputtering target of any of claims 1 through 8, wherein the amoun of the alloy of molybdenum and the at least on® additional alloying element, is about 40: to about 65 voi%.

10) The sputtering target of any of claims 1 through 9, wherein the alloy of molybdenum and the at least one additional alloying element includes a β-phase of molybdenum and titanium, in an amount greater than about 40 voi% of the alloy, of the target., or both.

11} A method for mating a sputtering: target of any of claims 1 throug 10, comprising the steps of;

a, providing first and second at least partially consolidated^' powder metal blocks eac optionally having a prepared surface, and each including an alloy including a refractory metal in an amount greater than about 30 percent by weight and at least one additional alloying element;

. interposing between the consolidated powder metal blocks at feast one continuous solid interface portion;

c. contacting the prepared surface of the first block indirectly With the prepared surface of the second block via the at least one continuous solid Interface portion in the substantia! absence of any bonding agent between the contacted surfaces to form a contacted joint structure; and

d, isostatica!!y pressing the contacted structure at a; temperature that Is less than about 1080°C at a pressure and for a time sufficient to reai e a consolidated joint between the first and second blocks.

12} The method of claim 11 ,. wherein the step of providing includes -step of forming the first and second blocks from an alloy that includes molybdenum, and at least one alloying element selected from titanium, chromium, niobium, tantalum, tungsten, zirconium or any combination thereof.

3} The method of claim 11 or 12, wherein th interposing step includes a step selected from (&^*} cold spraying a metal powder onto at least one of the blocks for forming the at least one continuous solid interface portion; (b) compacting a body of metal powder to forrft the at least one continuous solid interface portion; (c) sintering a body of a metal powder mixture to form the at least one continuous solid interface portion; ( ) cold spraying a metal powder into a die for fpnrisng the at least one continuous solid interface portion; {e} fcold spraying a. metal powder onto a substrate to form the at least one continuous solid interface portion that may include or omit the substrate; or if) any combination of (a) through (a). 14} The method of any of claims 1 through 13 wherein the step of isostatieaily pressing includes pressing at a temperature b tween about 500 and about 1080°C while the contacted structure is encapsulated in a sealed Vessel,

10} The method of any of claims 11. through 14, wherein the step of^■isosiaticaiiy pressing includes pressing at a pressure of at least about 70 MFa, while the contacted structure is encapsulates in a sealed vessel.

18) The method of any of cjaims 11 through 1S, wherein the step of isosiaticaiiy pressing includes maintaining a pressure of about 80 to about 140 MPa -at a temperature of about 7O0"C to about 108.0°C for a time of about one to about six hours while the contacted structure is encapsulated in a sealed vessel.

17) The method of any of claims 11 through 16, wherein the at ieast one alloying element is titanium, and the step of isosiaticaiiy pressing is performed under conditions sufficient so that a microsiruef e Is realized that is characterized as including a pure titanium phase, a .pure molybdenum phase and an alloy phase of titanium. and molybdenum,

18) The method of an of claims 11 throug 17, wherein the step of isosiaticaiiy pressing is performed under conditions sufficient so that the resulting consolidated joint provides a structure that has a transverse rupture strength per ASTM 8528-10, of at Ieast about 620 MPa,

19) The method of any of claims 11 through 18, wherein a resulting oxygen weight

concentration of the blocks of the sputtering target is between about 1000 ppm ¾nd 3500 ppm.

20) A sputtering target prepared by the method of any of claims 11 through 19.

21) _. The sputtering target of claim 20, wherein the target has a largest dimension of at least about 13 meters.

22) Use of a sputtering target of claim 20 or 2 .

23) A thin film made by sputtering with a sputtering target of either of claim 20 or 2 ,

24) An article employing a thin film of claim 23.

25} The article of claim 24, wherein the article is selected from a television, a video

display, a srnariphone, a tablet computer., a personal digital assistant, a navigation device, a sensor, a portable entertainment device, or a photovoltaic device.