WO1999061679A1

WO1999061679A1 - Target for pvd and similar processes

Info

Publication number: WO1999061679A1
Application number: PCT/US1999/012085
Authority: WO
Inventors: Kevin Williams
Original assignee: Sputtering Materials, Inc.
Priority date: 1998-05-28
Filing date: 1999-05-28
Publication date: 1999-12-02
Also published as: AU4410499A

Abstract

A PVD target (22) and method of making the same from a CVD process using metal-organic molecular precursors (18), particularly metal carbonyl or metal acetyl acetonates. The deposited target materials comprise metal, metal alloy, metal silicide, or metal oxide.

Description

TARGET FOR PVD AND SIMILAR PROCESSES

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of the filing of U.S. Provisional Patent Application Serial No. 60/087,371 , entitled, Target for Chemical Vapor Deposition, Physical Vapor Deposition and Similar Processes and Method of Making Same, filed on May 28, 1998, and the specification thereof is incorporated herein by reference.

BACKGROUND OF THE INVENTION Field of the Invention (Technical Field):

The present invention relates to targets for physical vapor deposition ("PVD") and similar processes.

Background Art:

Chemical vapor deposition, physical vapor deposition, and similar deposition processes are used in the fabrication of thin film materials. During deposition the desired material is deposited on a substrate surface to form a film of solid material. In PVD the source of the material deposited is often referred to as the target, which generally comprises an ultra-pure metal or an alloy thereof. Some PVD processes use laser ablation or pulsed laser deposition to release a controlled amount of target material in the form of a gas. The material gas is then transported to the heated substrate with which it then reacts to form the thin film. An accelerated plasma can also be used in the PVD process to deliver a heat pulse to the target to release a controlled amount of gaseous target material.

Physical vapor deposition, also known as sputtering, is a process whereby ions of an inert gas such as argon are electrically accelerated in a high vacuum toward a target of an ultra-pure metal or an alloy thereof. The ions physically chip off, or sputter, the target material, which is then deposited as a film on the surface of the substrate. Sputtering is the process often involved in the coating of a semiconductor wafer or other substrate mounted within a processing chamber. An inert gas is introduced into the processing chamber and an electric field is applied to ionize the inert gas. The positive ions of the inert gas bombard the target material and dislodge atoms from the target which are subsequently deposited onto the wafer or other substrate in the form of a thin film. The target is held within the deposition chamber by a device called a sputter coating source. The sputter coating source embodies electrical means for biasing the target material structure with a negative voltage, either DC for conductive targets, or RF for non-conductive targets, so the target will attract positive ions from the plasma of an inert gas. The sputter coating source also contains means for cooling the target structure and often magnetic means for containing and enhancing the plasma. Positive ions extracted from the plasma are then accelerated to a high kinetic energy and strike the surface of the target structure. A portion of the kinetic energy is transferred to the target atoms of the target material. Target atoms that obtain sufficient energy to overcome their respective binding energy escape from the target surface and are ejected into the deposition chamber. Objects, such as a substrate or semiconductor wafer, placed in the line of sight of the target source are then coated by the atoms ejected from the target surface.

Other PVD processes include electromagnetic PVD or use of an electron beam to chip-off or sputter the target material. In electromagnetic PVD processes, a magnetron or a high voltage modulator directs energy toward the target, which typically serves as a cathode. DC or AC high voltage modulators create a cathodic arc that releases highly charged ions from the target.

There are several methods of forming the target material, and the method used is generally chosen as a result of the physical properties of the material. For metals with relatively low melting points, and mixtures of these that form alloys, the most often used method is vacuum melting. Materials are mixed, melted together, and poured into a mold in a vacuum furnace. The vacuum furnace aids the outgassing of volatile constituents in the mix. After vacuum melting and cooling, the resulting ingot is sliced and machined to the desired final shape. After machining the target can be attached to a backing plate, which holds the target in the deposition chamber. Vacuum melting can provide specific compositions of homogeneous alloys, and results in materials that do not out-gas into the CVD chamber during sputtering. However, due to phase separation during cooling the number of homogeneous alloyed materials that can be prepared is limited. Also, the vacuum melting process requires that a considerable amount of expensive machining be employed to provide the final target profile.

Target materials with high melting points, such as tungsten and molybdenum, and mixtures of materials with one or more of the constituents having high melting points, are generally formed using powder metallurgy. The metals are first reduced to a powder. The powders are mixed and placed in a mold. High pressures and temperatures are then used to compact or sinter the powders to the point that the powders adhere and form a single, solid structure. The compacted shape is then machined to the final dimensions and joined to a backing plate. The methods of powder metallurgy have the advantage of fabrication to near net shape, avoiding much of the machining requirements associated with the vacuum melting process. However, there are disadvantages to fabricating target materials from powder metallurgical processes; the most critical being that the final target is of low density, and gases trapped during the high pressure process are released during sputtering. These trapped and unwanted gases contaminate the deposited film.

A CVD deposition process has also been used to prepare sputtering targets of the refractory metals, molybdenum, tungsten, titanium, and tantalum as well as their corresponding metal suicides. See, Jalby, et. al., U.S. Patent No. 5,0555,246. The CVD process utilizes the reaction of metal halide gases, WX₆, MoXe, TiX^ and TaX₅; X = Cl or F, with silicon hydride gas, Si_nH_2n+2 (n = 1 , 2, 3, . . .) to form the corresponding metal or metal suicide depending upon the relative flow rates of the two gases. However, one disadvantage to this process is that the refractory metal cannot be prepared free of the silicon. In a similar process, Jalby, et. al., U.S. Patent No. 5,230,847, teaches that the lowest amount of silicon that can be achieved by this process is about one part per hundred, i.e., MSio_.01. However, two Japanese patent applications, JP 6-228746 and JP 6-158300, teach the method of preparing molybdenum and tungsten targets relatively free from other metal and non- metal elements from the corresponding metal fluoride and reduction by dihydrogen in a CVD chamber. A major disadvantage of the Japanese process is the formation of hydrogen fluoride, a highly corrosive gas. The corrosive nature of hydrogen fluoride requires specialized and expensive fabrication equipment made of anti-corrosive materials, such as Monel™, and high maintence. Target materials can be formed by a variety of methods, including casting, pressing, hot pressing, extrusion, plasma spraying, and liquid dynamic compaction. For example, the manufacturing method for producing a target material via the hot pressing process comprises the steps of compressing first and second oxide powders followed by sintering to form a third oxide material. This material is then pulverized into a powder to form a new third oxide. The third oxide powder is then compressed under high temperatures and pressures. The hot pressing process method produces a target material that can later be used to deposit metal oxide thin films. Most of these techniques, however, have disadvantages similar to the vacuum melting process. Often it is desirable to form a target with a unique composition of metals and of metal oxides. During the hot pressing process, a multi-mixture may not always maintain phase uniformity or uniform grain size throughout the target material. The final phase and grain size of the target material is dependent upon the temperature profile and the cooling rate. If the temperature profile is uneven, the target may be anisotropic. That is, regions within the target may have a different phase, grain size, and vary in actual composition. During sputtering, such differences may lead to an unacceptable thin film.

Regardless of the method used to form the target material, the material must finally be formed to a final shape such as a disk, cone, square depending on the profile that is required for the particular deposition chamber. Some materials used in sputtering are very difficult to machine, and others are quite fragile. Target shape is an important variable in providing high quality films. PVD processes utilizing lasers, ion beam, electron beam or electromagnetic energy generally result in the non-uniform heating of the target material which results in uneven wear of the target material. This is primarily due to the electromagnetic field surrounding the target, as well as the temperature profile within the target. Often the electromagnetic field lines around the target will change as a function of the target's internal temperature profile. If left uncorrected, the target may wear non-uniformly or in a non-desirable fashion. Magnetic nozzles and ion acceleration grids that control the beam can minimize some of these target wear problems. Also, most disk shaped targets do not wear evenly during the sputtering process. Thus, some have attempted to match target shapes to specific wear profiles.

SUMMARY OF THE INVENTION .DISCLOSURE OF THE INVENTION.

The present invention is of a method for making PVD targets in the absence of molybdenum and tungsten hexafluoride, comprising: providing a substrate in a chemical vapor deposition chamber, providing at least one metal compound to the chemical vapor deposition chamber, reacting the metal compound, preferably in the chemical vapor deposition chamber, depositing the metal onto the substrate to form the target, and removing the resulting target from the chemical vapor deposition chamber. In the preferred embodiment, the substrate comprises a backing plate of a pre-determined shape. The preferred embodiment of the invention also includes at least one metal compound selected from the group consisting of metal carbonyl, metal acetyl acetonate, metal alkyl, and metal halide: preferrably, at least one metal compound selected from the group consisting of cobalt carbonyl, cobalt acetyl acetonate, ruthenium carbonyl, ruthenium acetyl acetonate, titanium hexacarbonyl, zirconium hexacarbonyl, hafnuim hexacarbonyl, niobium pentacarbonyl, tantalum pentacarbonyl, molybdenum hexacarbonyl, tungsten carbonyl, copper acetyl acetonate, silver acetyl acetonate, vanadium carbonyl, vanadium acetyl acetonate, chromium carbonyl, chromium acetyl acetonate, manganese carbonyl, manganese acetyl acetonate, rhodium carbonyl, rhodium acetyl acetonate, iridium carbonyl, iridium acetyl acetonate, platinum acetyl acetonate, nickel tetracarbonyl, and osmium carbonyl.

The PVD target resulting from the method of the present invention results in the deposition of at least one metal on a substrate, preferably a backing plate, by chemical vapor deposition. The metal or metals deposited are selected from the group consisting of niobium, tantalum, titanium, hafnium, zirconium, copper, cobalt, silver, vanadium, manganese, chromium, ruthenium, osmium, molybdenum, tungsten, rhodium, iridium, and platinum. In the invention, a single metal may be deposited or any combination of the listed metals to form an alloy. The invention is also of a method of depositing a thin film by a PVD process using a PVD target produced by providing a substrate in a chemical vapor deposition chamber, providing at least one metal compound to the chemical vapor deposition chamber, reacting the metal compound, preferably in the chemical vapor deposition chamber, depositing the metal onto the substrate to form the target, and removing the resulting target from the chemical vapor deposition chamber.

The invention is also of a PVD target produced by providing a substrate in a chemical vapor deposition chamber, providing at least one metal compound to the chemical vapor deposition chamber, reacting the metal compound in the chemical vapor deposition chamber, depositing the metal onto the substrate to form the target, and removing the resulting target from the chemical vapor deposition chamber.

The present invention is of a method for making metal suicide targets comprising: providing a substrate in a chemical vapor deposition chamber, providing at least one metal compound, with the exception of Xe, MoXe, TiX₄, and TaX where X = Cl or F, and at least one silicon compound to the chemical vapor deposition chamber, reacting the metal compound and silicon compound, preferably in the chemical vapor deposition chamber, depositing the metal and silicon onto the substrate to form the target and removing the resulting target from the chemical vapor deposition chamber. In the preferred embodiment, the substrate comprises a backing plate of a pre-determined shape. The preferred embodiment of the invention also includes providing at least one metal compound selected from the group consisting of metal carbonyl, metal acetyl acetonate, metal alkyl, and metal halide, and providing at least one silicon compound selected from the group consisting of silicon tetrachloride, silicon hydrides, and silicon chlorohydrides. Preferrably, at least one metal compound is selected from the group consisting of cobalt carbonyl, cobalt acetyl acetonate, ruthenium carbonyl, ruthenium acetyl acetonate, titanium hexacarbonyl, zirconium hexacarbonyl, hafnuim hexacarbonyl, niobium pentacarbonyl, tantalum pentacarbonyl, molybdenum hexacarbonyl, tungsten carbonyl, copper acetyl acetonate, silver acetyl acetonate, vanadium carbonyl, vanadium acetyl acetonate, chromium carbonyl, chromium acetyl acetonate, manganese carbonyl, manganese acetyl acetonate, rhodium carbonyl, rhodium acetyl acetonate, iridium carbonyl, iridium acetyl acetonate, platinum acetyl acetonate, nickel tetracarbonyl, and osmium carbonyl.

The metal silicide target resulting from the method of the present invention results in the deposition of at least one metal and silicon on a substrate, preferably a backing plate. In the preferred embodiment the metal or metals deposited are selected from the group consisting of niobium, tantalum, titanium, hafnium, zirconium, copper, cobalt, silver, vanadium, manganese, chromium, ruthenium, osmium, molybdenum, tungsten, rhodium, iridium, and platinum. In the invention, a single metal may be deposited to form a single metal silicide, MSi_z. Alternatively, any combination of the above metals can be deposited to form an alloyed silicide, M_mM'_nSi_z, M_mM'_nM"₀Si_z, etc.

The invention is also of a method of depositing a thin film through a PVD process using a PVD metal silicide target produced by providing a substrate in a chemical vapor deposition chamber, providing at least one metal compound and at least one silicon compound to the chemical vapor deposition chamber, reacting the metal compound and silicon compound, preferably in the chemical vapor deposition chamber, depositing the metal and silicon onto the substrate to form the target, and removing the resulting target from the chemical vapor deposition chamber.

The invention is also of a PVD target produced by providing a substrate in a chemical vapor deposition chamber, providing at least one metal compound and at least one silicon compound to the chemical vapor deposition chamber, reacting the metal compound and silicon compound, preferably in the chemical vapor deposition chamber, depositing the metal and silicon onto the substrate to form the target, and removing the resulting target from the chemical vapor deposition chamber. The present invention is of a PVD device comprising a target comprising a substrate and at least one metal deposited on said substrate by chemical vapor deposition. In the preferred embodiment, the substrate comprises a backing plate of a pre-determined shape, and the metal deposited comprises at least one metal, other than tungsten and molybdenum, selected from the group consisting of niobium, tantalum, titanium, hafnium, zirconium, copper, cobalt, silver, vanadium, manganese, chromium, ruthenium, osmium, rhodium, iridium, and platinum.

The present invention is of a PVD device comprising a target comprising a substrate and at least one metal and silicon deposited on said substrate by chemical vapor deposition. In the preferred embodiment, the substrate comprises a backing plate of a pre-determined shape, and the metal deposited comprises at least one metal, other than tungsten, molybdenum, tantalum, and titanium, selected from the group consisting of niobium, hafnium, zirconium, copper, cobalt, silver, vanadium, manganese, chromium, ruthenium; osmium, rhodium, iridium, and platinum.

A primary object of the present invention is the process of making target materials having properties that are highly desirable for producing high quality thin films with uniform crystal size and layer thickness.

A further object of the present invention is to provide metal, metal alloy, metal silicide, or metal oxide target materials of ultra-high purity, select grain size, or high densities.

A primary advantage of the present invention is that target materials comprised of various metals and non-metals can be produced with relatively high phase uniformity, selected densities, and selected grain sizes.

A further advantage of the present invention is the target material is grown directly onto the backing plate, thus eliminating the manufacturing step joining the target to the backing plate with either a soldering or an adhesive process.

A further advantage of the present invention is the target material can be grown to specific shapes with specific molds, thus eliminating the need for costly and extensive machining of the target material. A further advantage of the present invention is the target material can be refilled following partial depletion using the same process used for the backing plates. This process is especially important for precious metals.

Other objects, advantages and novel features, and further scope of applicability of the present invention will be set forth in part in the detailed description to follow, taken in conjunction with the accompanying drawings, and in part will become apparent to those skilled in the art upon examination of the following, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are incorporated into and form a part of the specification, illustrate several embodiments of the present invention and, together with the description, serve to explain the principles of the invention. The drawings are only for the purpose of illustrating a preferred embodiment of the invention and are not to be construed as limiting the invention. In the drawings:

Fig. 1 is a schematic diagram of the CVD deposition apparatus of the invention used to make a nickel target from nickel carbonyl; and

Fig. 2 is a schematic diagram of the CVD deposition apparatus used to make a target from any cobalt metal carbonyl.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

(BEST MODES FOR CARRYING OUT THE INVENTION.

The present invention is of a device and method for building a target through a chemical vapor deposition (CVD) process. The targets formed by the invention have properties that are highly desirable for producing a thin film with uniform crystal size and layer thickness. The invention also allows for the design of metal alloy and metal silicide targets over a wide compositional range. Overall, the invention enables the production and use of targets with comparatively superior properties and characteristics.

In the specification and claims, the term "reacting" includes, but is not limited to, the metal compound decomposing prior to or when in contact with the substrate and combining with other metal or silicon compounds prior to or when in contact with the substrate, in the case of the metal carbonyl compounds, the term "decomposition" includes, but is not limited to, the loss of one or more of the carbon monoxide ligands from the metal compound.

In the specification and claims, the term "acetyl acetonates" is used in its generic form and includes the named "acetyl" derivative, CH₃C(0)CHC(0)CH₃ as well as the other alkyl derivatives known in the art, including, but not limited to ethyl, phenyl, and t-butyl.

The present invention is of a class of PVD targets comprising metal, metal alloys, metal suicides, and metal oxides, and the method of making same by chemical vapor deposition processes. The preferred method of making such targets is by utilizing metal-organic molecular precursors, such as the class of metal carbonyl and metal acetyl acetonates. The metal-organic precursors can be produced in situ from the corresponding metal powder and carbon monoxide gas under known temperatures and pressures, or purchased commercially and stored in an appropriate vessel, commonly known in the art as a bubbler.

The bubbler is comprised of an inlet and outlet flow whereby during deposition an inert or other carrier gas, preferably argon, enters the bubbler and exits the bubbler with the metal-organic precursor. For most metal carbonyis and metal acetyl acetonates used in the invention, the bubbler is heated to the appropriate temperature to increase and maintain a constant vapor pressure of the metal-organic precursor within the bubbler. Through maintenance of a constant vapor pressure the amount of metal-organic precursor released to the CVD chamber is controlled by the flow of the inert or other carrier gas. Some metal-organic precursors, e.g., Ni(CO)4, do not require transfer by a carrier gas to the CVD chamber. The apparatus for making targets by CVD preferably includes a parallel series of bubblers, each containing a different metal-organic precursor.

The metal-organic precursor may react prior to entering the CVD chamber, within the CVD chamber, or on the heated substrate. Preferably, the deposition parameters, i.e., substrate temperature, partial and total pressures, and metal mass flow rates, are designed such that the metal-organic precursor reacts with the substrate. In the case of the metal carbonyis, the metal carbonyl reacts with the substrate to form the metal target and carbon monoxide. The carbon monoxide is vented from the CVD chamber. In the case of the metal acetyl acetonates, the metal acetyl acetonate reacts with the substrate to form the metal target and various organic products.

These organic products are vented from the CVD chamber. As is known in the art, it is important that the temperature profile of the substrate be uniformly maintained to prevent uneven deposition of the target metal. The uniform temperature control in combination with the substrate or the predetermined shaped backing plate in the present invention results in the formation of a select target shape.

Following deposition of the target material onto the backing plate, the target along with the backing plate is removed from the deposition chamber and shipped to the end-user. The target shape may also be refined while still in the CVD chamber or in an adjacent chamber by controlled ion or electron beam, laser ablation, or similar processes. Alternatively, some machining may be necessary outside the CVD chamber. The target can also be packaged in a non-oxidizing environment to prevent surface oxidation during shipping.

In contrast to the wide variety of target processing methods presently available, the present invention offers a single processing method for a wide range of metals as well as their alloys. In the present invention, the same or similar processing method is used for both high melting refractory metals, such as tungsten and tantalum, and relatively low melting metals, such as titanium. Moreover, the same or similar processing method is used when an alloy is made from a high and low melting metal, such as a tungsten-titanium alloy. In other words, a tungsten, titanium, or tungsten- titanium target can be fabricated by the same or very similar deposition equipment.

The use of metal carbonyis or in some cases the metal acetyl acetonates in the present invention results only in the formation of the pure metal or alloy and an organic by product. The corrosive gases such as hydrogen fluoride or hydrogen chloride gas that are produced from the reaction of the corresponding metal halides with the reducing gas dihydrogen are not produced by the present invention. This has tremendous advantages in regard to the original costs of capital equipment as well as the maintenance of the equipment.

The present invention also results in target materials with the desired properties required by the semiconductor industry. Unlike targets made from hot pressing, the present invention results in target metals and alloys of high densities with negligible amounts of trapped impurities. Also, the present invention offers the opportunity to select optimal grain size of the final target by slight changes in operating conditions, such as flow rates and temperatures. Target density and grain size are major factors to be considered in the fabrication of high quality thin films.

The present invention also eliminates the need to attach the final target material to the backing plate of the sputtering device since the target is deposited directly onto the backing plate. The target material can also be deposited to any particular shape since the final shape will depend upon the selected shape of the backing plate. This eliminates the need to extensively machine the final material to a desired shape, thus allowing the target to wear uniformly throughout the process of depositing the thin film. Also, once the chip producer depletes the source of the target material, the backing plate can be shipped back to the manufacturer and the target re-deposited. This is an especially important option when rare and expensive metals, such as osmium or iridium, are selected by the chip manufacturer.

The invention produces targets comprising all materials currently used in physical vapor deposition and similar processes. For instance, the process may be used for fabricating target materials comprising niobium, tantalum, titanium, hafnium, zirconium, copper, cobalt, silver, vanadium, manganese, chromium, ruthenium, osmium, molybdenum, tungsten, rhodium, iridium, and platinum as well as their alloys, suicides, oxides and other compounds.

The process of the present invention also enables the formation of high density targets with variable grain sizes including grain sizes of less than 500 microns.

Industrial Applicability:

The invention is further illustrated by the following non-limiting examples. Example 1

The making of a nickel target according to the invention from the corresponding nickel carbonyl is described as follows. First, the nickel carbonyl was produced by reacting nickel powder with carbon monoxide gas at about approximately 60 to 80° C and 10 to 16 atmospheres. The nickel carbonyl that was generated was cooled to room temperature and stored as a liquid in a pressure vessel 10, Fig. 1. The coating chamber 12 was connected to the nickel carbonyl storage tank according to Fig.1. The liquid nickel carbonyl was first transferred from the storage tank and heated slightly in a pre-chamber 14 to generate nickel carbonyl gas. The gas was then transferred to the CVD chamber where the nickel carbonyl reacted with the heated substrate 16 at about approximately 180° C and 1 atmosphere of total pressure. Nickel metal was deposited on the substrate and CO gas is liberated. Lower processing temperatures were also used, however deposition rates decreased at the lower temperatures.

Example 2

The making of a cobalt target according to the invention from the corresponding cobalt carbonyl is described as follows. Solid Co₂(CO)₈ was stored at low temperature in a storage vessel 18 connected directly to the CVD chamber 20, Fig. 2. The CVD chamber was evacuated to about approximately 10^~6 torr, the valve between the CVD chamber and the storage vessel was opened and the Cobalt deposited on the substrate 22 located within the CVD chamber 20 at about approximately 25° C. Alternatively, a cobalt target can be made from the corresponding cobalt acetyl acetonate as described as follows. The cobalt acetyl acetonate is placed in a storage vessel, commonly known to those in the art as a bubbler, and heated slightly to increase its vapor pressure. An inert gas, preferably argon, flowing through the bubbler transfers the cobalt acetyl acetonate in the gaseous state to the CVD chamber. The cobalt acetyl acetonate reacts with the heated substrate at about approximately 300 to 500 ° C depositing cobalt metal on the substrate.

Example 3

The making of a tantalum or niobium target according to the invention from the corresponding tantalum or niobium pentacarbonyl is described as follows. The pentacarbonyl is placed in a bubbler, and heated slightly to increase its vapor pressure. An inert gas, preferably argon, flowing through the bubbler transfers the carbonyl in the gaseous state to the CVD chamber. The pentacarbonyl reacts with the heated substrate at about approximately 400 to 700 ° C. Tantalum or niobium metal is deposited on the substrate and CO gas is liberated.

Example 4

The making of a ruthenium target according to the invention from Ru(CO)₅ is described as follows. The coating chamber is connected to the Ru(CO) storage tank similar to that described in example 1. The liquid Ru(CO)₅is transferred from the storage tank and heated to generate ruthenium carbonyl gas. The gas is then transferred to the CVD chamber where the Ru(CO)₅ reacts with the heated substrate at about approximately 150 to 300° C. Ruthenium metal is deposited on the substrate and CO gas is liberated.

Alternatively, solid Ru₃(CO)ι₂ is placed in a bubbler, and heated slightly to increase its vapor pressure. An inert gas, preferably argon, flowing through the bubbler transfers the Ru₃(CO)ι₂ in the gaseous state to the CVD chamber. The Ru₃(CO)ι₂ reacts with the heated substrate at about approximately 200 to 500 ° C.

Alternatively, the ruthenium acetyl acetonate is placed in a bubbler, and heated slightly to increase its vapor pressure. An inert gas, preferably argon, flowing through the bubbler transfers the ruthenium acetyl acetonate in the gaseous state to the CVD chamber. The ruthenium acetyl acetonate reacts with the heated substrate at about approximately 500 to 700 ° C.

Example 5

The making of an osmium target according to the invention from Os₃(CO)₁₂ is described as follows. The solid Os₃(CO)ι₂ is placed in a bubbler, and heated slightly to increase its vapor pressure. An inert gas, preferably argon, flowing through the bubbler transfers the Os₃(CO)₁₂ in the gaseous state to the CVD chamber. The Os₃(CO)₁₂ reacts with the heated substrate at about approximately 200 to 500 ° C.

Example 6

The making of a titanium target according to the invention from the corresponding titanium carbonyl is described as follows. The titanium carbonyl is placed in a bubbler, and heated slightly to increase its vapor pressure. An inert gas, preferably argon, flowing through the bubbler transfers the titanium carbonyl in the gaseous state to the CVD chamber. The carbonyl reacts with the heated substrate at about approximately 300 to 600 ° C. Titanium metal is deposited on the substrate and CO gas is liberated.

Example 7 The making of a zirconium or hafnium target according to the invention target from the corresponding zirconium or hafnium carbonyl is described as follows. The carbonyl is placed in a bubbler, and heated slightly to increase its vapor pressure. An inert gas, preferably argon, flowing through the bubbler transfers the carbonyl in the gaseous state to the CVD chamber. The carbonyl reacts with the heated substrate at about approximately 400 to 700 ° C. Zirconium or hafnium metal is deposited on the substrate and CO gas is liberated.

Example 8

The making of a copper target according to the invention from the corresponding copper acetyl acetonate is described as follows. The copper acetyl acetonate is placed in a bubbler, and heated slightly to increase its vapor pressure. An inert gas, preferably argon, flowing through the bubbler transfers the copper acetyl acetonate in the gaseous state to the CVD chamber. The copper acetyl acetonate reacts with the heated substrate at about approximately 300 to 700 ° C.

Example 9

The making of a silver target according to the invention from the corresponding silver acetyl acetonate is described as follows. The silver acetyl acetonate is placed in a bubbler, and heated slightly to increase its vapor pressure. An inert gas, preferably argon, flowing through the bubbler transfers the silver acetyl acetonate in the gaseous state to the CVD chamber. The silver acetyl acetonate reacts with the heated substrate at about approximately 300 to 700 ° C.

Example 10

The making of a molybdenum or tungsten target according to the invention from the corresponding hexacarbonyl is described as follows. The solid Mo(C0)₆ or W(CO)₆ is placed in a bubbler, and heated slightly to increase its vapor pressure. An inert gas, preferably argon, flowing through the bubbler transfers the hexacarbonyl in the gaseous state to the CVD chamber. The hexacarbonyl reacts with the heated substrate at about approximately 300 to 700 ° C depositing molybdenum and tungsten.

Example 11 The making of a metal silicide target according to the invention where the metal comprises either tantalum, tungsten, titanium, or molybdenum from the corresponding metal carbonyl and silicon hydride gas Si_nH_2n+2 (n = 1 , 2, 3, . . . ) is described as follows. The solid metal carbonyl is placed in a bubbler, and heated slightly to increase its vapor pressure. An inert gas, preferably argon, flowing through the bubbler transfers the metal carbonyl in the gaseous state from the bubbler. Prior to injection into the chamber the metal carbonyl is mixed with the silicon hydride gas. The metal carbonyl and the silicon hydride gas react with the heated substrate at about approximately 600 to 900 ° C to from MSi_z (z = 0.2 to 3.0). The final stoichiometric composition of the metal silicide depends upon the processing temperature and the corresponding flow rates of the metal carbonyl and silicon hydride gas.

Example 12 The making of a tungsten-titanium alloy target according to the invention from the corresponding metal carbonyis is described as follows. The solid metal carbonyis are placed in separate bubblers and are heated slightly to increase their vapor pressure. An inert gas, preferably argon, flowing through the bubblers transfers the metal carbonyis in the gaseous state from the bubbler. Prior to injection into the chamber the metal carbonyis are allowed to mix. The metal carbonyis react with the heated substrate at about approximately 400 to 700 ° C to from WTi_z (z = 0.4 to 40). The final stoichiometric composition of the tungsten-titanium alloy depends upon the processing temperature and the corresponding flow rates of the respective metal carbonyis.

The preceding examples can be repeated with similar success by substituting the generically or specifically described reactants and/or operating conditions of this invention for those used in the preceding examples.

Although the invention has been described in detail with particular reference to these preferred embodiments, other embodiments can achieve the same results. Variations and modifications of the present invention will be obvious to those skilled in the art and it is intended to cover in the appended claims all such modifications and equivalents. The entire disclosures of all references, applications, patents, and publications cited above are hereby incorporated by reference.

Claims

CLAIMSWhat is claimed is:

1. A method for making targets in the absence of molybdenum and tungsten hexafluoride, the method comprising the steps of: a) providing a substrate in a chemical vapor deposition chamber; b) providing at least one metal compound to the chemical vapor deposition chamber; c) reacting the metal compound in the chemical vapor deposition chamber; d) depositing the metal onto the substrate to form the target; and e) removing the resulting target from the chemical vapor deposition chamber.

2. The method according to claim 1 wherein providing a substrate comprises providing a backing plate of a pre-determined shape.

3. The method according to claim 1 wherein providing at least one metal compound comprises providing at least one metal compound selected from the group consisting of metal carbonyl, metal acetyl acetonate, metal alkyl, and metal halide.

4. The method according to claim 3 wherein providing at least one metal compound comprises providing at least one metal compound selected from the group consisting of cobalt carbonyl, cobalt acetyl acetonate, ruthenium carbonyl, ruthenium acetyl acetonate, titanium hexacarbonyl, zirconium hexacarbonyl, hafnuim hexacarbonyl, niobium pentacarbonyl, tantalum pentacarbonyl, molybdenum hexacarbonyl, tungsten carbonyl, copper acetyl acetonate, silver acetyl acetonate, vanadium carbonyl, vanadium acetyl acetonate, chromium carbonyl, chromium acetyl acetonate, manganese carbonyl, manganese acetyl acetonate, rhodium carbonyl, rhodium acetyl acetonate, iridium carbonyl, iridium acetyl acetonate, platinum acetyl acetonate, nickel tetracarbonyl, and osmium carbonyl.

5. The method according to claim 1 wherein the depositing step comprises depositing at least one metal selected from the group consisting of niobium, tantalum, titanium, hafnium, zirconium, copper, cobalt, silver, vanadium, manganese, chromium, ruthenium, osmium, molybdenum, tungsten, rhodium, iridium, and platinum.

6. A method of depositing a thin film through a PVD process using a target produced according to the method of claim 1.

7. A PVD target made according to the method of claim 1.

8. A method for making targets, the method comprising the steps of: a) providing a substrate in a chemical vapor deposition chamber; b) providing at least one metal compound, with the exception of WXe, MoXe, TiX₄, and TaX₅ where X = Cl or F, to the chemical vapor deposition chamber; c) providing at least one silicon compound to the chemical vapor deposition chamber; d) reacting the metal compound and silicon compound in the chemical vapor deposition chamber; e) depositing the metal and silicon onto the substrate to form the target; and f) removing the resulting target from the chemical vapor deposition chamber.

9. The method according to claim 8 wherein providing a substrate comprises providing a backing plate of a pre-determined shape.

10. The method according to claim 8 wherein providing at least one metal compound comprises providing at least one metal compound selected from the group consisting of metal carbonyl, metal acetyl acetonate, metal alkyl, and metal halide.

11. The method according to claim 10 wherein providing at least one metal compound comprises providing at least one metal compound selected from the group consisting of cobalt carbonyl, cobalt acetyl acetonate, ruthenium carbonyl, ruthenium acetyl acetonate, titanium hexacarbonyl, zirconium hexacarbonyl, hafnuim hexacarbonyl, niobium pentacarbonyl, tantalum pentacarbonyl, molybdenum hexacarbonyl, tungsten carbonyl, copper carbonyl, silver acetyl acetonate, vanadium carbonyl, vanadium acetyl acetonate, chromium carbonyl, chromium acetyl acetonate, manganese carbonyl, manganese acetyl acetonate, rhodium carbonyl, rhodium acetyl acetonate, iridium carbonyl, iridium acetyl acetonate, platinum acetyl acetonate, nickel tetracarbonyl, and osmium carbonyl.

12. The method according to claim 8 wherein providing at least one silicon compound comprises providing at least one silicon compound selected from the group consisting of silicon tetrachloride, silicon hydrides, and silicon chlorohydrides.

13. The method according to claim 8 wherein the depositing step comprises depositing at least one metal selected from the group consisting of niobium, tantalum, titanium, hafnium, zirconium, copper, cobalt, silver, vanadium, manganese, chromium, ruthenium, osmium, molybdenum, tungsten, rhodium, iridium, and platinum.

14. A PVD target made according to the method of claim 8.

15. A method of depositing a thin film through a PVD process using a target produced according to the method of claim 8.

16. A PVD device comprising a target comprising a substrate and at least one metal deposited on said substrate by chemical vapor deposition.

17. The PVD device according to claim 16 wherein said substrate comprises a backing plate of a pre-determined shape.

18. The PVD device according to claim 16 wherein the metal deposited comprises at least one metal, other than tungsten and molybdenum, selected from the group consisting of niobium, tantalum, titanium, hafnium, zirconium, copper, cobalt, silver, vanadium, manganese, chromium, ruthenium, osmium, rhodium, iridium, and platinum.

19. A PVD device comprising a target comprising a substrate and at least one metal, other than tungsten, molybdenum, titanium, and tantalum, and silicon deposited on said substrate by chemical vapor deposition.

20. The PVD device according to claim 19 wherein said substrate comprises a backing plate of a pre-determined shape.

21. The PVD device according to claim 19 wherein the metal deposited comprises at least one metal selected from the group consisting of niobium, hafnium, zirconium, copper, cobalt, silver, vanadium, manganese, chromium, ruthenium, osmium, rhodium, iridium, and platinum.