KR20170081680A - Cost effective monolithic rotary target - Google Patents

Abstract

A monolithic rotary target is described. The target includes a sputter region and a flange region, the sputter region is made of a first material, and the flange region is made of a first material. The sputter region and the flange region are formed integrally.

Description

[0001] COST EFFECTIVE MONOLITHIC ROTARY TARGET [0002]

The embodiments described herein relate to layer deposition by sputtering from a target. Embodiments described herein relate specifically to devices including rotary sputter targets and rotary sputter targets. In particular, the disclosure relates to an apparatus for depositing a layer of material on a substrate comprising monolithic rotary targets and monolithic rotary targets.

Known techniques for depositing thin layers on a substrate are in particular evaporation, chemical vapor deposition and sputter deposition. For example, sputtering can be used to deposit a thin layer, such as a thin layer of metal, e.g., aluminum, or ceramic. During the sputtering process, the coating material is transported from the sputtering target composed of the material to be deposited to the substrate by impinging ions on the surface of the target. During the sputtering process, the target is electrically biased such that the ions generated in the process region may impinge on the target surface with sufficient energy to remove atoms of the target material from the target surface. The sputtered atoms can be deposited on the substrate. Alternatively, the sputtered atoms may react with a gas in a plasma such as, for example, nitrogen or oxygen to deposit an oxide, nitride or oxynitride of material on the substrate, for example: this may be referred to as reactive sputtering .

There are two general types of sputtering targets, planar sputtering targets, and rotary sputtering targets. Both flat sputtering targets and rotary sputtering targets have advantages. Due to the geometry and design of the cathodes, the rotary targets have higher utilization and increased operating time than planar targets. Rotary sputtering targets can be particularly useful in large area substrate processing.

High purity metal and metal alloy sputtering targets can be used in semiconductor manufacturing. For example, high purity aluminum alloy sputtering targets can be used in semiconductor manufacturing. Similarly, other metals and metal alloy sputtering targets from, for example, copper, titanium, molybdenum sputtering targets may be used. In view of the material quality, the metal and metal alloy targets may be provided as monolithic targets, i.e., targets without backing tubes. In the case of monolithic targets, the target material itself, which is the material to be deposited on the substrate, can be self-supporting. The target material does not require a backing tube to support the target material.

The semiconductor industry and other industries have a continuing need for manufacturing cost savings including, but not limited to, the cost of ownership of manufacturing equipment that also includes targets. Therefore, there is a continuing need for cost-effective, mechanically reliable rotary targets.

In view of the above, there is provided a monolithic rotary target according to independent claims 1, 9 and 15, a device for depositing a layer of material on a substrate, and a method for manufacturing a monolithic rotary target . Additional aspects, advantages, and features of embodiments of the disclosure are apparent from the dependent claims, the description and the accompanying drawings.

According to one aspect, a monolithic rotary target is provided. The target includes a sputter region and a flange region, the sputter region is made of a first material, and the flange region is made of a first material. The sputter region and the flange region are formed integrally.

According to another aspect, an apparatus for depositing a material is provided. The apparatus includes a process chamber and at least one monolithic rotary target comprising a sputter region and a flange region, wherein the sputter region and the flange region are made of a first material.

According to yet another aspect, a method of manufacturing a monolithic rotary target comprising a sputter region and a flange region is provided. The method includes the step of integrally forming a sputter region and a flange region from the same material.

A more particular description of the embodiments briefly summarized above may be made with reference to the embodiments described herein, in the manner in which the above-recited features of the disclosure embodiments can be understood in detail. BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings relate to embodiments of the present disclosure and are described below:
FIG. 1A illustrates a cross-sectional view of a monolithic rotary target along an axis of rotation, in accordance with the embodiments described herein.
Figure 1B illustrates the details of the flange region of a monolithic rotary target, in accordance with the embodiments described herein.
Figure 2a shows a cross-sectional view of a monolithic rotary target with a reusable cap along its axis of rotation, in accordance with the embodiments described herein.
Figure 2B illustrates details of a reusable cap of a monolithic rotary target, in accordance with the embodiments described herein.
Figure 3 shows a top view of a monolithic rotary target, in accordance with the embodiments described herein.
Figure 4 shows a top view of a deposition apparatus in which monolithic rotary targets are provided therein, in accordance with the embodiments described herein.
Figure 5 shows a top view of another deposition apparatus in which monolithic rotary targets are provided therein, in accordance with the embodiments described herein.

Reference will now be made in detail to various embodiments of the disclosure, and one or more examples of the disclosure are illustrated in the drawings. In the following description of the drawings, like reference numerals refer to like components. In general, only the differences to the individual embodiments are described. Each example is provided as an illustration of an embodiment of the disclosure, and is not intended to limit the embodiments. Further, the features illustrated or described as part of one embodiment may be used in other embodiments or with other embodiments to yield yet another embodiment. The description is intended to include such modifications and variations.

In the art of sputtering, the sputtering target assembly may have a sputtering target and a backing plate or a backing tube. For example, the target may be bonded onto a backing plate or backing tube made of a backing tube, such as stainless steel, copper, aluminum or alloys thereof. This configuration of the bonding process and target assembly not only adds cost to the entire assembly, but also creates the risk of adding weight during use and de-bonding the target assembly. With the continued progress of the industry to use increasingly larger targets, this risk of de-bonding is further increased. Since the backing plate can be made of a material different from the target material, there is a risk of further contamination caused by these materials present with the target material. Thus, monolithic targets may be preferred.

The term "monolithic " as used herein refers to a single piece target unit without any separate or attached backing plate structure or backing tube structure.

Monolithic targets usually have a target area, i.e., a sputter area, and a flange area made of a different material compared to the sputter area. Monolithic rotary targets can be produced by casting or sintering of the target material. Thus, a metal or metal alloy billet may be pressurized to a predetermined height, for example, at room temperature. Recrystallization annealing of the billet is then performed, followed by quenching at room temperature. The recrystallized billets can be mechanically cold worked.

Figure 1A shows a monolithic rotary target 100 along a rotation axis 10. The monolithic rotary target 100 may include a sputter region 110 and a flange region 120. The sputter region may be made of a first material. The flange region may be made of the same material as the sputter region. As shown in FIG. 1A, the sputter region 110 and the flange region 120 may be integrally formed. The first material may be a material to be deposited on the substrate. Thus, during sputtering of the target, material can also be sputtered from the flange region if it can occur for any reason, without the risk of contamination caused by other materials present with the rotary target. According to some embodiments, which may be combined with other embodiments described herein, the flange region 120 may include a flange 122 and a middle portion 320. The intermediate portion 320 may be provided between the flange 122 and the sputter region 110. The flange region 120 may also be adapted for attachment of the rotatable target 100 to an end-block within the process chamber or deposition apparatus by using bolts or other mechanical fasteners (not shown) . The end-block can be configured for rotation of the rotary target during sputtering. Additionally, or additionally, the end-block may be configured to provide cooling fluid and / or power to the target for its sputtering.

The term "rotatable target " as used herein refers to any cathode assembly including a target structure adapted to be rotatably mounted to a deposition apparatus and adapted to be sputtered. Thus, the term "rotatable target" is used herein synonymously with "rotary cathode ". Similarly, the term "sputter region" as used herein refers to any shell formed of a material suitable for being sputtered, in particular as a hollow cylinder. According to further embodiments that may be combined with other embodiments described herein, the rotary target may be cylindrical, for example, so that the distance between the substrate and the target surface is constant during rotation of the rotary target. Further, in accordance with other further embodiments that may be combined with other embodiments described herein, the rotatable target includes a single deposition material as compared to sputtering applications, and switching between different target materials may be accomplished by either The switching between different targets is provided by the rotational movement of different targets, or the switching between different targets is provided by the rotational movement of different targets.

FIG. 1B shows an enlarged cross-sectional view of the flange region 120 of FIG. 1A. According to some embodiments that may be combined with other embodiments described herein, the flange area may be provided with increased strength. Thus, the target deflection during sputtering is reduced, and the mechanical reliability of the target is improved. As a result, a cost effective and mechanically reliable target is provided. According to some embodiments that may be combined with other embodiments described herein, this may be advantageously used for cantilever targets that are supported only at one end of the target.

According to different embodiments that may be combined with other embodiments described herein, the flange region 120 may undergo a working process. According to further embodiments, which may be combined with other embodiments described herein, the work process may be a work hardening process that can increase the strength of the material in the flange region. According to embodiments of the present disclosure, the work process may create a permanent deformation on the material within the flange region. As a result, the strength of the flange region can increase. Examples of work hardening processes may include induction hardening, shot peening, bead blasting, mechanical rolling, and the like.

High frequency curing can be used to selectively cure areas of the assembly or regions of the piece without affecting the properties of the assembly as a whole or piece. According to these embodiments, during high frequency curing, the flange region 120 can be heated by high frequency heating and then be etched. The so-called flanged region can undergo a martensitic transformation to increase its hardness. Shot peening can be used to create a compressive residual stress layer and to change the mechanical properties of the metals. According to these embodiments, which may be combined with other embodiments described herein, during shot peening, the surface of the flange region 120 may have a shot (e.g., Round metallic, glass or ceramic particles).

As can be seen from FIG. 1A, the flange region 120 may be adjacent to the sputtering region 110 of the target 100. Thus, increased strength can be provided to reduce target deflection during sputtering and to improve the mechanical reliability of the target. As a result, a cost effective and mechanically reliable target is provided.

According to further embodiments that may be combined with other embodiments described herein, the monolithic rotary target 100 may include a cap 210, for example, a reusable cap as shown in Figure 2a, . The cap 210 may be made of a second material. The second material may be different from the first material.

According to embodiments of the present disclosure, the first material may comprise metals and metal alloys such as aluminum and aluminum alloys. In particular, the first material may be high purity aluminum. In particular, the first material may be 5N Al with 99.999 wt-% purity. According to further embodiments, which may be combined with other embodiments described herein, the metal and metal alloy may be selected from the group consisting of copper, titanium, molybdenum, chromium and zinc. More specifically, the metal alloy may be selected from the group consisting of grade 3.8 to 4.9 wt-% copper, 3.0 to 3.9 wt-% titanium, and 3.0 to 3.95 wt-% molybdenum.

According to other further embodiments that may be combined with other embodiments described herein, the first material may comprise semiconductor materials and dielectric materials (e.g., ceramics). These materials can be used when it is possible to produce monolithic targets from themselves.

According to different embodiments that may be combined with other embodiments described herein, the second material may comprise a metal or a metal alloy. Specifically, the second material may be a metal alloy. More specifically, the second material may be an Al alloy.

According to the embodiments described herein, the cap 210 may be a reusable cap 210. The reusable cap may be adjacent the sputter region 110 in the longitudinal direction of the target and be opposed to the flange region 120. The reusable cap may provide a sealed interior of the target, for example, where a cooling fluid may be provided. In addition, the reusable cap provides a cost effective method of manufacturing a sealed interior of the target. According to some embodiments that may be combined with other embodiments described herein, the reusable cap 210 may be attached, e.g., screwed, to the target 100. Thus, the reusable cap and target may include threads. For example, the reusable cap may include a male thread, and the target may include a female thread. As a result, the reusable cap can be screwed onto the target, as shown in Figure 2B. The attachment between the male and female threads is shown at 230.

According to other further embodiments that may be combined with other embodiments described herein, the target and / or cap may include threads such that a screw may be used to attach the cap to the target. Alternatively, the cap may be attached to the target by other means, for example, the cap may be welded to the target. However, the welded cap may not be reusable.

Figure 3 is a side view of a monolithic rotary target 100 including a flange region 120 including a sputter region 110 and a flange 122 and a middle portion 320, according to embodiments described herein. Fig. As shown in FIG. 3, the sputter region 110 and the flange 122 may be coaxial with each other. The intermediate portion 320 may be provided between the flange 122 and the sputter region 110. Accordingly, the sputter region, the flange, and the intermediate portion may be coaxial with each other.

According to embodiments of the present disclosure, the outer diameter of the middle portion may be smaller than the outer diameter of the sputter region. Similarly, the outer diameter of the flange may optionally be larger than the outer diameter of the middle portion and larger than the outer diameter of the sputter region. According to different embodiments that may be combined with other embodiments described herein, the outer diameter of the flange may be 165 mm or more, specifically 171 mm or more, more specifically 190 mm or more. The outer diameter of the intermediate portion may be 145 mm or more, specifically 160 mm or more, more specifically 170 mm or more. The inner diameter of the target may be 125 mm or more, specifically 130 mm or more, more specifically 135 mm or more. Thus, the wall thickness of the middle portion in the radial direction may be 5 mm or more and / or 25 mm or less, specifically 7 mm to 20 mm.

FIG. 4 illustrates a deposition apparatus 400 having a process chamber 402 and at least one monolithic rotary target 100. Each monolithic rotary target 100 may include a sputter region and a flange region. The sputter region and the flange region may be made of a first material. The first material may be a material to be deposited on the substrate. Thus, during sputtering of the target, the material can also be sputtered from the flange region without the risk of contamination caused by other materials present with the rotatable target. The flange region may also be adapted for attachment of the monolithic rotary target 100 to the process chamber 402 or deposition apparatus 400 by using bolts or other mechanical fasteners (not shown).

According to further embodiments, which may be combined with other embodiments described herein, increased strength may be provided to the flange region of the monolithic rotary cathode. Thus, the target deflection during sputtering is reduced and the mechanical reliability of the target is improved. As a result, a cost effective deposition apparatus having mechanically reliable targets is provided.

According to other further embodiments that may be combined with other embodiments described herein, the monolithic rotary target 100 may be a monolithic rotary cathode.

The process chamber 402 may be configured to be evacuated. For example, the process chamber may have a vacuum flange 413. In addition, a pumping system (not shown) may be connected to the chamber 402 to provide a technical vacuum within the chamber. Vacuum can be suitably provided for the sputtering process. For example, the process pressure may be between 1 x 10 ^-3 and 10 x 10 ³ mbar.

The substrate support 422 may support the substrate 410 during deposition of the layer or thin film on the substrate by the rotating cathodes. The cathodes may be biased with respect to the anode and / or with respect to the chamber walls. In addition, the substrate 410 or the substrate support 422 may be biased thereon for deposition of a layer.

According to embodiments of the present disclosure, the rotating cathodes may be provided as pairs of cathodes, e.g. rotatable MF Twin-cathodes. For a ceramic target such as ITO, a DC sputtering process may be provided wherein the cathodes are biased with a DC voltage. According to further embodiments, which may be combined with other embodiments described herein, sputtering from a silicon target, an aluminum target, a molybdenum target, or the like may be performed by MF sputtering, i.e., intermediate frequency sputtering. According to embodiments of the present disclosure, the intermediate frequency may be a frequency in the range of 5 kHz to 100 kHz, such as 10 kHz to 50 kHz. Sputtering from the target to the transparent conductive oxide film can be performed as DC sputtering.

According to different embodiments that may be combined with other embodiments described herein, the substrate support 422 in the chamber 402 may be a support pedestal, and the substrate 410 may be an actuator, such as a robot arm, May be provided on a pedestal together. Alternatively, the substrate support may be part of a substrate transfer system, where the rollers may be provided to transfer the substrate into and out of the chamber 402. The roller system can guide the substrate or carrier, which in turn returns the substrate to the inside.

According to other different embodiments that may be combined with other embodiments described herein, in the case of a transport system, the substrate 410 may also be deposited in an in-line process. In an in-line process, the substrate may be moved through the chamber 402 during deposition. In this case, a chamber opening having a valve unit 408, etc. may also be provided on the side of the chamber 402. In addition, another chamber may be provided on the side of the chamber 402 facing the chamber 401. According to further embodiments, the chamber 401 may be a transfer chamber that includes a load-lock chamber, e.g., a robot, or may be a transfer chamber including a processing chamber, such as, for example, a deposition chamber, Lt; / RTI >

According to some embodiments that may be combined with other embodiments described herein, the embodiments described herein may be used for display PVD, i.e., sputter deposition on large area substrates for the display market . According to some embodiments, large area substrates or carriers with carriers having a plurality of substrates may have a size of at least 0.67 m < 2 >. The size may be from about 0.67 m (0.73 x 0.92 m - Gen 4.5) to about 8 m ² , more typically from about 2 m ² to about 9 m ² , or even up to 12 m ² . The substrates or carriers on which the structures, devices, e.g., cathode assemblies and methods, in accordance with the embodiments described herein, are provided are large area substrates as described herein. For example, a large area substrate or carrier may have GEN 4.5 corresponding to about 0.67 m 2 substrates (0.73 x 0.92 m), GEN 5 corresponding to about 1.4 m 2 substrates (1.1 m x 1.3 m), about 4.29 m ² substrates GEN 10 corresponding to (1.95 mx 2.2 m) GEN 7.5 , approximately 5.7 of the substrate of the ^{m 2 (2.2 mx 2.5 m)} GEN 8.5, or even from about 8.7 m ² substrates (2.85 mx 3.05 ㎛) corresponding to the corresponding to the Lt; / RTI > Higher generations such as GEN 11 and GEN 12 and corresponding substrate regions may similarly be implemented.

Figure 5 shows a schematic view of a deposition chamber 500 in accordance with the embodiments described herein. The deposition chamber 500 may be adapted to a deposition process such as a PVD or CVD process. One or more substrates may be placed on the substrate transport device. According to some embodiments, the substrate support may be moveable to allow adjustment of the position of the substrate within the chamber. Specifically, in the case of a large area substrate as described herein, deposition with vertical substrate orientation or essentially vertical substrate orientation can be performed. The transfer device may have lower rollers 522 and lower rollers 522 may be driven by one or more drives 525, e.g., motors. The drives 525 may be connected to the roller 522 by a shaft 523 for rotation of the roller. Thus, for example, it may be possible for one motor to drive more than one roller by connecting rollers and belts, gear systems, and the like.

The rollers 524 may be used for supporting the substrates in a vertical or essentially vertical position. The substrates may be vertical or may deviate slightly (e.g., up to 5 [deg.]) From the vertical position. Large-area substrates having substrate sizes from 1 m 2 to 9 m 2 may be very thin, for example less than 1 mm, such as 0.7 mm or even 0.5 mm. To support the substrate and provide the substrates in a fixed position, the substrates may be provided to the carrier during processing of the substrates. Thus, while the substrates are supported within the carrier, they may be transported, for example, by a transport system comprising a plurality of rollers and drives. For example, a carrier having substrates therein can be supported by a system of rollers 522 and rollers 524.

A source of deposition material, i. E., A rotary target, according to embodiments described herein may be provided in the processing chamber toward the side of the substrate to be coated. The source of the deposition material may provide a first material 565 (i.e., an evaporation material) to be deposited on the substrate. As shown in FIG. 5 and according to the embodiments described herein, the rotatable target may be a monolithic rotary target 100 comprising a sputter region and a flange region made of the same material. The sputter region and the flange region may be integrally formed.

According to some embodiments, the deposition material indicated by reference numeral 565 during layer deposition may be selected according to the deposition process of the coated substrate and the subsequent application. For example, the deposition material of the monolithic rotary target may be a material selected from the group consisting of metals, metal alloys, semiconductor materials, and dielectric materials. Thus, an oxide-layer, a nitride-layer, or a carbide-layer, which may include these materials, may be deposited by providing the material from a source or by reactive deposition, i.e. the material from the source may be deposited from the processing gas And reacts with elements such as oxygen, nitride, or carbon.

According to the embodiments described herein, a monolithic rotary target is a PVD chamber available from AKT < ( ^R) >, a subsidiary of Applied Materials, Inc. of Santa Clara, California, or Applied Materials Gmbh ≪ RTI ID = 0.0 > PVD < / RTI > However, the sputtering target assembly is useful in other PVD chambers, including those configured to process large-area substrates, substrates in the form of continuous webs, large-area circular substrates, and those chambers fabricated by other manufacturers As will be understood by those skilled in the art.

According to some embodiments that may be combined with other embodiments described herein, the monolithic rotary target 100 may be a magnet assembly for obtaining increased deposition rates. A magnet assembly, which may include an array of magnets, may be arranged within the sputtering target, for example in a monolithic rotary target, and may provide a magnetic field for magnetically enhanced sputtering. The target may be rotatable about its longitudinal axis so that it can be rotated relative to the magnetic means.

During operation, the magnet means can become hot. This is due to the fact that they are surrounded by target material bombarded with ions. Impacts on the resulting target material may result in heating of the rotating cathode. To keep the magnet at the proper operating temperature, cooling of the target material and magnets may be provided.

According to other further embodiments that may be combined with other embodiments described herein, a tubular internal structure may be used to cool the monolithic rotary target. In particular, the tubular internal structure can be used to cool the magnet assembly. The tubular internal structure can be mounted liquid-tightly in a coolant tube (not shown). Thus, a cooling fluid, e.g., water, can be circulated within the monolithic rotary target 100 to cool the magnets and / or the target.

According to one aspect, a monolithic rotary target is provided. The target includes a sputter region and a flange region, the sputter region is made of a first material, and the flange region is made of a first material. The sputter region and the flange region are formed integrally.

According to another aspect, a monolithic rotary target is provided. The target includes a sputter region and a flange region, the sputter region is made of a first material, and the flange region is made of a first material. The sputter area and the flange area are formed integrally, and the flange area is provided with increased strength.

According to another aspect, an apparatus for depositing a material is provided. The apparatus includes a process chamber and at least one monolithic rotary target comprising a sputter region and a flange region, wherein the sputter region and the flange region are made of a first material.

While the foregoing is directed to embodiments of the present disclosure, other and further embodiments may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.

Claims (15)

A monolithic rotary target comprising a sputter region and a flange region,
Wherein the sputter region is made of a first material, the flange region is made of the first material,
Wherein the sputter region and the flange region are integrally formed,
Monolithic rotary targets. The method according to claim 1,
Wherein the flange region is provided with increased strength,
Monolithic rotary targets. 3. The method according to claim 1 or 2,
The flange region may be formed of a material that undergoes a working process,
Monolithic rotary targets. 4. The method according to any one of claims 1 to 3,
Wherein the flange region is adjacent a sputter region of the target,
Monolithic rotary targets. 5. The method according to any one of claims 1 to 4,
Comprising a cap,
Said cap being made of a second material different from said first material,
Monolithic rotary targets. 6. The method of claim 5,
The cap is a reusable cap,
Wherein the reusable cap is adjacent to the sputter region and opposite the flange region in the longitudinal direction of the target,
Monolithic rotary targets. 7. The method according to any one of claims 1 to 6,
Wherein the first material comprises metals, metal alloys, semiconductor materials, and dielectric materials.
Monolithic rotary targets. 8. The method according to any one of claims 5 to 7,
Wherein the second material comprises metals, metal alloys, semiconductor materials, and dielectric materials.
Monolithic rotary targets. 9. The method according to any one of claims 1 to 8,
Wherein the flange region comprises a flange and an intermediate portion,
Monolithic rotary targets. 10. The method of claim 9,
The wall thickness of the intermediate portion in the radial direction is 5 mm or more, in particular 7 mm to 20 mm,
Monolithic rotary targets. 11. The method according to claim 9 or 10,
Wherein an outer diameter of the intermediate portion is smaller than an outer diameter of the sputter region,
Monolithic rotary targets. An apparatus for depositing a material,
A process chamber; And
At least one monolithic rotary target comprising a sputter region and a flange region
/ RTI >
Wherein the sputter region and the flange region are made of a first material,
Apparatus for the deposition of materials. 13. The method of claim 12,
Wherein the at least one monolithic rotary target is a monolithic rotary cathode,
Apparatus for the deposition of materials. The method according to claim 12 or 13,
Wherein the at least one monolithic rotary target comprises a magnet assembly,
Apparatus for the deposition of materials. A method of manufacturing a monolithic rotary target comprising a sputter region and a flange region,
Wherein the sputter region and the flange region are integrally formed from the same material,
A method for manufacturing a monolithic rotary target.

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