CN102361004B - Barrier layer and seed layer integrated - Google Patents

Abstract

The present invention generally relates to filling features by depositing a barrier layer, depositing a seed layer on the barrier layer, and depositing a conductive layer on the seed layer. In one embodiment, the seed layer includes a copper alloy seed layer deposited on the barrier layer. For example, a copper alloy seed layer may include copper and metals such as aluminum, magnesium, titanium, zirconium, tin, and combinations thereof. In another embodiment, the seed layer includes a copper alloy seed layer deposited on the barrier layer and a second seed layer deposited on the copper alloy seed layer. The copper alloy seed layer may include copper and metals such as aluminum, magnesium, titanium, zirconium, tin, and combinations thereof. The second seed layer may comprise a metal, such as undoped copper. In yet another embodiment, the seed layer includes a first seed layer and a second seed layer. The first seed layer may include metals such as aluminum, magnesium, titanium, zirconium, tin, and combinations thereof. The second seed layer may comprise a metal, such as undoped copper.

Description

Integration of barrier and seed layers

The present invention is a divisional application of a patent application whose PCT international filing date is September 9, 2002, application number is 02821308.4, and the invention name is "integration of barrier layer and seed layer".

technical field

The present invention generally relates to apparatus and methods for depositing barrier layers and seed layers over the barrier layers. More particularly, the present invention relates to apparatus and methods for depositing barrier layers and depositing seed layers comprising copper and other metals over the barrier layers.

Background technique

Reliable fabrication of sub-micron or smaller features is one of the keys to next-generation large-scale integration (VLSI) and ultra-large-scale integration (ULSI) of semiconductor devices. However, the shrinking dimensions of interconnects in VLSI and ULSI technologies place additional demands on process capability due to the strip-limited circuit technology. The multilevel interconnects at the heart of this technology require precise processing of high aspect ratio features such as vias and other interconnects. The reliable formation of these interconnections is very important to the success of VLSI and ULSI, as well as to the continuing effort to increase the circuit density and quality of individual substrates.

As circuit density increases, the width of vias, contacts, and other features, as well as the dielectric material between them, decreases to submicron dimensions (e.g., less than 0.20 microns or less), while the thickness of the dielectric layer is substantially less. As a result, the aspect ratio of the features, i.e. their height divided by their width, increases. Many conventional deposition processes have difficulty filling submicron structures with aspect ratios greater than 4:1, especially at aspect ratios greater than 10:1. Accordingly, substantial efforts are being made to form substantially void-free and seam-free submicron features with high aspect ratios.

Currently, copper and its alloys are the metals of choice for submicron interconnects because copper has a lower resistivity than aluminum (1.7 μΩ-cm, compared to 3.1 μΩ-cm for aluminum), and higher current carrying capacity capability and much higher resistance to electromigration. These properties are important both to support the higher current densities experienced at multilevel integration and to increase device speed. Also, copper has good thermal conductivity and is available in a high purity state.

Copper metallization can be achieved by various techniques. A typical method generally involves physical vapor deposition of a barrier layer on the feature, physical vapor deposition of a copper seed layer on the barrier layer, and then electroplating a layer of copper conductive material on the copper seed layer to fill the feature. Finally, the deposited layers and dielectric layers are planarized, such as by chemical mechanical polishing (CMP), to define conductive interconnect features.

One problem with using copper, however, is that the copper diffuses into silicon, silicon dioxide, and other dielectric materials, potentially compromising device integrity. Therefore, conformal barrier layers are becoming more and more important to prevent copper diffusion. Tantalum nitride has been used as a barrier material to prevent copper from diffusing into underlying layers. However, one problem with previously used tantalum nitride and other barrier layers is that these barrier layers are poor wetting agents for copper to be deposited thereon. For example, when depositing a copper seed layer on these barrier layers, the copper seed layer may agglomerate and become discontinuous, which may prevent consistent deposition of a layer of copper conductive material (eg, an electroplated copper layer) on the copper seed layer. In other instances, subsequent processing at elevated temperatures of substrate structures having copper layers deposited over these barrier layers may result in dewetting and voiding. In yet another example, thermal stress in a device formed using the device may result in voiding in the copper layer and damage to the device. Accordingly, there is a need for improved interconnect structures and methods of depositing interconnect structures.

Contents of the invention

The invention generally relates to filling features by depositing a barrier layer, depositing a seed layer on the barrier layer, and depositing a conductive layer on the seed layer. In one embodiment, the seed layer includes a copper alloy seed layer deposited on the barrier layer. For example, a copper alloy seed layer may include copper and metals such as aluminum, magnesium, titanium, zirconium, tin, and combinations thereof. In another embodiment, the seed layer includes a copper alloy seed layer deposited on the barrier layer and a second seed layer deposited on the copper alloy seed layer. The copper alloy seed layer may include copper and metals such as aluminum, magnesium, titanium, zirconium, tin, and combinations thereof. The second seed layer may comprise a metal, such as undoped copper. In yet another embodiment, the seed layer includes a first seed layer and a second seed layer. The first seed layer may include metals such as aluminum, magnesium, titanium, zirconium, tin, and combinations thereof. The second seed layer may comprise a metal, such as undoped copper.

Description of drawings

In order that the above features, advantages and objects of the invention may be obtained and understood in detail, a more particular description of the invention briefly summarized above may be had by reference to the embodiments illustrated in the accompanying drawings.

It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may apply to other equally effective embodiments.

Figure 1 is a schematic cross-sectional view of one embodiment of a processing system that may be used to form one or more barrier layers by atomic layer deposition;

Figure 2A is a schematic cross-sectional view of one embodiment of a substrate with a dielectric layer deposited thereon.

Figure 2B is a schematic cross-sectional view of one embodiment of forming a barrier layer on the substrate structure of Figure 2A.

3A-C illustrate one embodiment of alternating chemisorbed monolayers of tantalum-containing compounds and nitrogen-containing compounds on a portion of a substrate at the stage of barrier layer formation.

4 is a schematic cross-sectional view of one embodiment of a chemical vapor deposition capable processing system that can be used to deposit a copper alloy seed layer.

5A-C are schematic cross-sectional views of an embodiment of depositing a seed layer on the barrier layer of FIG. 2B.

Figure 6 is a schematic top view of one example of a multi-chamber processing system.

detailed description

Process chamber suitable for depositing barrier layers

1 is a schematic cross-sectional view of one exemplary embodiment of a processing system 10 that may be used to form one or more barrier layers by atomic layer deposition in accordance with aspects of the present invention. Of course, other processing systems may also be used.

Processing system 10 generally includes processing chamber 100 , gas panel 130 , control unit 110 , power supply 106 and vacuum pump 102 . The processing chamber 100 generally houses a support 150 for supporting a substrate, such as a semiconductor wafer 190 , within the processing chamber 100 .

In the processing chamber 100 , the support 150 may be heated by embedded heating elements 170 . For example, the pedestal may be resistively heated by providing electrical current from an AC power source to the heating element 170 . In turn, wafer 190 is heated by support 150 and may be maintained within a desired processing temperature range, eg, in a range between about 20°C and about 1000°C, depending on the particular process.

A temperature sensor 172 such as a thermocouple may be embedded in the wafer support 150 to monitor the support temperature. For example, the measured temperature can be used in a feedback loop to control the current applied from the power supply 106 to the heating element 170 so that the wafer temperature can be maintained or controlled at a desired temperature or a desired temperature suitable for a certain processing application within range. The support 150 may also be heated using radiant heating (not shown) or other heating methods.

A vacuum pump 102 may be used to evacuate process gases from the process chamber 100 and may be used to help maintain a desired pressure or a desired pressure within a pressure range within the process chamber 100 . Holes 120 through the walls of the processing chamber 100 are used to introduce processing gases into the processing chamber 100 . The size of the aperture 120 generally depends on the size of the processing chamber 100 .

The bore 120 is partially connected to a gas panel 130 through a valve 125 . A gas panel 130 may be arranged to receive and then provide final process gases from two or more gas sources 135 , 136 to the process chamber 100 through holes 120 and valves 125 . The gas sources 135 , 136 may store the precursor in a liquid state at room temperature, which is then heated while in the gas panel 130 to convert the precursor to a vapor state for introduction into the processing chamber 100 . The gas sources 135, 136 may also be adapted to provide the precursors by using a carrier gas. Gas panel 130 may in turn be configured to receive and then provide purge gas from purge gas source 138 to process chamber 100 through aperture 120 and valve 125 . Showerhead 160 may be connected to hole 120 to supply process gas, cleaning gas, or other gas to wafer 190 on support 150 .

The showerhead 160 and the support 150 may serve as separate electrodes for providing an electric field to trigger the plasma. RF power source 162 may be connected to showerhead 160, RF power source 163 may be connected to mount 150, or RF power sources 162, 163 may be connected to spray head 160 and mount 150, respectively. The matching network 164 may be connected to the RF power sources 162 , 163 and may be connected to the control unit 110 so as to control the power supplied to the RF power sources 162 , 163 .

A control unit 110, such as a programmable personal computer, workstation computer, etc., may also be configured to control the flow of different process gases through the gas panel 130 and valves 125 at different stages of the wafer processing process. Exemplarily, the control unit 110 includes a central processing unit (CPU) 112 , support circuitry 114 and a memory 116 containing associated control software 113 . In addition to controlling the process gases passing through the gas panel 130, the control unit 110 may be arranged to be responsible for automatic control of other activities in wafer processing, such as wafer transport, temperature control, chamber pumping, among other activities, some of which will be described elsewhere in this paper.

The control unit 110 may be one of any form of general purpose computer processor used in an industrial setting for controlling the different process chambers and sub-processors. CPU 112 may use any suitable memory 116, such as random access memory, read only memory, floppy disk drive, hard disk, or any other form of data storage, local or remote. Various support circuits may be connected to CPU 112 for supporting system 10 . The required software routines 113 may be stored in memory 116 or executed by a remotely located (not shown) second computer processor. Bi-directional communications between control unit 110 and various other components of wafer processing system 10 are handled through a number of digital cables, collectively referred to as signal bus 118 , some of which are shown in FIG. 1 .

barrier layer formation

The exemplary processing chamber depicted in FIG. 1 can be used to perform the following processes. Of course, other processing chambers may also be used. 2A-2B illustrate an exemplary embodiment of barrier layer formation for fabricating an interconnect structure in accordance with one or more aspects of the present invention.

Figure 2A is a schematic cross-sectional view of one embodiment of a substrate 200 with a dielectric layer 202 deposited thereon. Depending on the processing stage, substrate 200 may be a silicon semiconductor wafer or a layer of other material formed on the wafer. Dielectric layer 202 may be an oxide, silicon oxide, silicon carbon oxide, fluorosilicon, porous dielectric, or other suitable dielectric formed and patterned to provide a dielectric layer extending to exposed surface portion 202T of substrate 200 Contact hole or via 202H. For clarity, substrate 200 refers to any workpiece on which thin film processing is performed, and substrate structure 250 is used to represent substrate 200 and other material layers formed on substrate 200 , such as dielectric layer 202 . Those skilled in the art should also understand that the present invention can be used in a dual damascene process flow.

2B is a schematic cross-sectional view of one embodiment of forming a barrier layer 204 on the substrate structure 250 of FIG. 2A by atomic layer deposition (ALD). Preferably, the barrier layer comprises a tantalum nitride layer. Examples of other barrier layer materials that can be used include titanium (Ti), titanium nitride (TiN), titanium silicon nitride (TiSiN), tantalum (Ta), tantalum silicon nitride (TaSiN), tungsten (W), nitride Tungsten (WN), Tungsten Silicon Nitride (WSiN), and combinations thereof.

For reasons of clarity, the deposition of the barrier layer will be described in more detail with reference to an embodiment of a barrier layer comprising a tantalum nitride barrier layer. In one aspect, the atomic layer deposition sequence for a tantalum nitride barrier layer includes providing a tantalum-containing compound and a nitrogen-containing compound into a processing chamber, such as the processing chamber of FIG. 1 . Sequentially providing the tantalum-containing compound and the nitrogen-containing compound may result in alternating chemisorption of multiple monolayers of the tantalum-containing compound and multiple monolayers of the nitrogen-containing compound on the substrate structure 250 .

3A-C illustrate alternating chemisorption of multiple monolayers of a tantalum-containing compound and multiple monolayers of a nitrogen-containing compound on an exemplary portion of a substrate 300 during stages of integrated circuit fabrication, more particularly during barrier layer formation. In FIG. 3A, a monolayer of a tantalum-containing compound is chemisorbed on a substrate 300 by introducing a pulse of a tantalum-containing compound 305 into the processing chamber as shown in FIG. The chemisorption process for adsorbing a monolayer of tantalum-containing compound 305 is believed to be self-limiting in that since the surface of the substrate has a limited number of sites for chemisorption of tantalum-containing compound, only one during a given pulse The monolayer is chemisorbed onto the surface of the substrate 300 . Once a limited number of sites are occupied by the tantalum-containing compound 305, any further chemisorption of the tantalum-containing compound will be prevented.

Tantalum-containing compound 305 typically includes tantalum atoms 310 with one or more active species 315 . In one embodiment, the tantalum-containing compound may be a tantalum-based organometallic precursor or a derivative thereof. Preferably, the organometallic precursor is pentadimethylamino-tantalum (PDMAT; Ta(NMe ₂ ) ₅ ). PDMAT can be advantageous for many reasons. PDMAT is relatively stable. PDMAT has an appropriate vapor pressure, which makes supply easy. In particular, PDMAT can be produced with low halide content. The halide content of PDMAT can be produced with a halide content of less than 100 ppm, and can even be produced with a halide content of less than 30 ppm or even less than 5 ppm. Without wishing to be bound by theory, it is believed that a low halide content organometallic precursor is beneficial because halides, such as chlorine, contained in the barrier layer may attack the copper layer deposited thereon.

The tantalum-containing compound may be other organometallic precursors or derivatives thereof, such as but not limited to pentaethylmethylamino-tantalum (PEMAT: Ta[N(C ₂ H ₅ CH ₃ ) ₂ ] ₅ ), Pentadiethylamino-tantalum (PDEAT: Ta(NEt ₂ ) ₅ ), and any and all derivatives of PEMAT, PDEAT or PDMAT. Other tantalum-containing compounds include, but are not limited to, TBTDET (Ta(NEt ₂ ) ₃ NC ₄ H ₉ or C ₁₆ H ₃₉ N ₄ Ta) and tantalum halides such as TaX ₅ , where X is fluorine (F), bromine (Br ) or chlorine (Cl), and derivatives thereof.

The tantalum-containing compound can be provided as a gas or with the aid of a carrier gas. Carrier gases that may be used include, but are not limited to, helium (He), argon (Ar), nitrogen ( _N2 ) and hydrogen ( _H2 ).

After the monolayer of tantalum-containing compound is chemisorbed to substrate 300, excess tantalum-containing compound is removed from the processing chamber by introducing a pulse of purge gas into the processing chamber. Purge gases that may be used include, but are not limited to, helium (He), argon (Ar), nitrogen (N ₂ ), hydrogen (H ₂ ), and others.

Referring to FIG. 3B, after cleaning the processing chamber, a pulse of nitrogen-containing compound 325 is introduced into the processing chamber. The nitrogen-containing compound 325 may be provided alone, or with the aid of a carrier gas. The nitrogen-containing compound 325 may include nitrogen atoms 330 with one or more reactive species 335 . The nitrogen-containing compound preferably includes ammonia gas (NH ₃ ). Other nitrogen-containing compounds that may be used include, but are not limited to: N _x H _{y where} x and y are integers (e.g. hydrazine (N ₂ H ₄ )), dimethyl hydrazine ((CH ₃ ) ₂ N ₂ H ₂ ) , butylhydrazine (C ₄ H ₉ N ₂ H ₃ ), phenylhydrazine (C ₆ H ₅ N ₂ H ₃ ), other hydrazine derivatives, nitrogen plasma source (eg N ₂ , N ₂ / H ₂ , NH ₃ , or N ₂ H ₄ plasma), 2,2'-azoisobutane ((CH ₃ ) ₆ C ₂ N ₂ ), ethyl azide (C ₂ H ₅ N ₃ ), and other suitable gases. A carrier gas can be used to supply nitrogen-containing compounds, if desired.

The monolayer of nitrogen-containing compound 325 may be chemisorbed on the monolayer of tantalum-containing compound 305 . The composition and structure of the precursors on the surface during atomic layer deposition (ALD) is not precisely known. Without wishing to be bound by theory, it is believed that the chemisorbed monolayer nitrogen-containing compound 325 reacts with the monolayer tantalum-containing compound 305 to form the tantalum nitride layer 309 . The reaction species 315, 335 form by-products 340 that can be transported from the substrate surface by the vacuum system. The reaction of the nitrogen-containing compound 325 with the tantalum-containing compound 305 is believed to be self-limiting because only a monolayer of the tantalum-containing compound 305 is chemisorbed on the substrate surface. In another theory, the precursor may be in an intermediate state while on the substrate surface. In addition, the deposited tantalum nitride layer may also contain elements more than the simple elements of tantalum (Ta) and nitrogen (N); instead, the tantalum nitride layer may also contain elements having carbon (C), hydrogen (H) and/or Or a more complex molecule of oxygen (O).

After the monolayer of nitrogen-containing compound 325 is adsorbed on the monolayer of tantalum-containing compound, any excess nitrogen-containing compound is removed by introducing another pulse of purge gas into the process chamber. Then, as shown in Figure 3C, the sequence of alternating chemisorbed tantalum nitride layer deposition sequences of monolayers of tantalum-containing compounds and nitrogen-containing compounds can be repeated, if desired, until the desired tantalum nitride thickness is achieved.

In FIGS. 3A-3C , tantalum nitride layer formation is depicted starting with chemisorption of a monolayer of a tantalum-containing compound on the substrate, followed by a monolayer of a nitrogen-containing compound. Alternatively, tantalum nitride layer formation may begin with chemisorption of a monolayer of a nitrogen-containing compound on the substrate, followed by a monolayer of a tantalum-containing compound. Furthermore, in an alternative embodiment, pumping alone between pulses of reactant gas may be used to prevent mixing of reactant gases.

For each pulse of tantalum-containing compound, nitrogen-containing compound and purge gas, the duration is variable and depends on the volumetric capacity of the process chamber used and the vacuum system connected thereto. For example, (1) lower gas pressure requires longer pulse time; (2) lower gas flow rate requires longer time for chamber pressure to rise and stabilize, requiring longer pulse time; (3) large volume processing It takes longer for the chamber to fill, longer for the chamber pressure to stabilize, and thus longer pulse times. Similarly, the time between each pulse is also variable and depends on the volumetric capacity of the processing chamber and the vacuum system connected thereto. In general, the duration of one pulse of a tantalum-containing compound or a nitrogen-containing compound should be long enough to chemisorb a monolayer of the compound. Typically, the pulse of the purge gas is long enough to remove reaction by-products and/or any residual material left in the process chamber.

In general, pulse times of about 1.0 second or less for tantalum-containing compounds and about 1.0 second or less for nitrogen-containing compounds are typically sufficient to chemisorb alternating monolayers on the substrate. A pulse time of about 1.0 second or less for the purge gas is typically sufficient to remove reaction by-products as well as any residual material left in the process chamber. Of course, longer pulse times can be used to ensure chemisorption of tantalum and nitrogen-containing compounds and to ensure removal of reaction by-products.

During atomic layer deposition, the substrate can be maintained substantially below the thermal decomposition temperature of the selected tantalum-containing compound. For the tantalum-containing compounds demonstrated herein, an exemplary heater temperature range used is approximately between about 20°C and about 500°C at process chamber pressures of less than 100 Torr, preferably less than 50 Torr. When the tantalum-containing gas is PDMAT, the heater temperature is preferably between about 100°C and about 300°C, more preferably between about 175°C and about 250°C. In other embodiments, it should be understood that other temperatures may be used. For example, temperatures above the thermal decomposition temperature may be used. However, the temperature should be chosen such that more than 50% of the deposition takes place by chemisorption processes. In another example, a temperature above the thermal decomposition temperature can be used, wherein the amount of decomposition during each precursor deposition is limited such that the growth mode is similar to the atomic layer deposition growth mode.

An exemplary process sequence for depositing a tantalum nitride layer by atomic layer deposition in the processing chamber as in the processing chamber of FIG. Pentadimethylamine tantalum (PDMAT) is provided at a flow rate of about 1.0 second or less for a period of time, and ammonia is provided at a flow rate of between about 100 seem and about 1000 seem for about 1.0 second or less, preferably at a flow rate of between about 200 seem and about 500 seem and providing the purge gas for about 1.0 seconds or less at a flow rate between about 100 seem and about 1000 seem, preferably between about 200 seem and about 500 seem. The heater temperature is preferably maintained between about 100°C and about 300°C, and the process chamber pressure is between about 1.0 and about 5.0 Torr. This process provides thicknesses between about 0.5 Angstroms and about 1.0 Angstroms per cycle. Alternating sequences can be repeated until the desired thickness is achieved.

In one embodiment, a barrier layer, such as a tantalum nitride barrier layer, is deposited with a sidewall coverage of about 50 Angstroms or less. In another embodiment, the barrier layer is deposited with a sidewall coverage of about 20 Angstroms or less. In yet another embodiment, the barrier layer is deposited with a sidewall coverage of about 10 Angstroms or less. A barrier layer with a thickness of about 10 Angstroms or less is considered to be an adequate barrier layer to prevent copper diffusion. In one aspect, thin barrier layers have the advantage that they can be used to fill submicron or smaller features with high aspect ratios. Of course, barrier layers with sidewall coverage greater than 50 Angstroms may be used.

The barrier layer can be further plasma annealed. In one embodiment, the barrier layer can be plasma annealed with argon plasma or argon/hydrogen plasma. The RF power supplied to the RF electrodes may be between about 100W and about 2000W, preferably between about 500W and about 1000W for a 200mm diameter substrate, and preferably between about 1000W and about 2000W for a 300mm diameter substrate. The pressure of the processing chamber may be less than 100 Torr, preferably between 0.1 Torr and about 5 Torr, more preferably between about 1 Torr and 3 Torr. The heater temperature may be between about 20°C and about 500°C. Plasma annealing can be performed in one cycle, multiple cycles, or after barrier layer formation.

In the above, embodiments of barrier layer atomic layer deposition were described as chemisorption of a reactant monolayer on a substrate. The invention also includes embodiments in which the reactants are deposited as more or less than a monolayer. The invention also includes embodiments in which the reactants are not deposited in a self-limiting manner. The invention also includes embodiments in which the barrier layer 204 is deposited primarily in a chemical vapor deposition process in which the reactants are supplied sequentially or simultaneously. The invention also includes embodiments in which the barrier layer 204 is deposited by a physical vapor deposition process in which the target comprises the material to be deposited (ie, a tantalum target in nitrogen for deposition of tantalum nitride).

Process chamber suitable for depositing the seed layer

In one embodiment, the seed layer may be deposited by any suitable technique, such as physical vapor deposition, chemical vapor deposition, electroless deposition, or a combination of these techniques. Suitable physical vapor deposition techniques for depositing the seed layer include high density plasma physical vapor deposition (HDPPVD) or collimated or long stroke sputtering. One type of HDPPVD is self-ionized plasma physical vapor deposition. An example of a processing chamber capable of physical vapor deposition of a seed layer from an ionized plasma is a SIP™ chamber, available from Applied Materials, Inc. of Santa Clara, California. An exemplary embodiment of a processing chamber capable of physical vapor deposition from an ionizing plasma is described in US Patent 6,183,614, entitled "RotatingSputter Magnetron Assembly," which is incorporated herein by reference to the extent not inconsistent with the present invention.

Figure 4 is a schematic cross-sectional view of one embodiment of a physical vapor deposition capable processing system 410 that may be used to deposit a seed layer. Of course, other processing systems and other types of physical vapor deposition can also be used.

The processing system 410 includes a vacuum chamber 412 sealed to a PVD target 414 consisting of material to be sputter deposited on a wafer 416 which is secured to a heater mount 418 . A shield 420 secured within the chamber protects the walls of the chamber 412 from sputtered material and provides an anode ground plane. An optional DC power supply 422 negatively biases the target 414 relative to the shield 420 .

A gas source 424 provides a sputtering working gas, typically the chemically inert gas argon, to the process chamber 412 via a mass flow controller 426 . A vacuum system 428 maintains the processing chamber at a low pressure. A computer-based controller 430 controls the reactor including DC power supply 422 and mass flow controller 426 .

When argon is admitted into the process chamber, a DC voltage between the target 414 and the shield 420 ignites the argon into a plasma, and the positively charged argon ions are attracted to the negatively charged target 414 . The ions bombard the target 414 with sufficient energy to cause target atoms or beams of atoms to be sputtered from the target 414 . Some of the target particles bombard wafer 416, thereby depositing thereon, forming a thin film of target material.

In order to provide efficient sputtering, a magnetron 432 is positioned behind the target 414 . It has opposing magnets 434, 436 in the vicinity of which magnets 434, 436 generate a magnetic field within the processing chamber. The magnetic field traps electrons, and in order to maintain electrical neutrality, the ion density is also increased, thereby forming a high density plasma region 438 within the process chamber adjacent to the magnetron 432 . The magnetron 432 generally rotates about an axis of rotation 458 located at the center of the target 414 to achieve complete coverage when sputtering the target 414 .

Seat 418 creates a DC self-bias that attracts ionized particles from the plasma through the plasma sheath adjacent wafer 416 . This effect can be enhanced by additional DC or RF biasing of the pedestal electrode 418 to provide additional acceleration of the ionized particles passing through the plasma sheath towards the wafer 416, thereby controlling the directionality of the sputter deposition.

seed layer formation

The exemplary processing chamber shown in FIG. 4 can be used to implement the following processes. Of course, other processing chambers may be used. 5A-5C are schematic cross-sectional views of exemplary embodiments of depositing a seed layer on a barrier layer.

One embodiment shown in FIG. 5A includes depositing a copper alloy seed layer 502 on the barrier layer 204 of FIG. 2B and depositing a copper conductive material layer 506 on the seed layer 502 to fill the features. The term "copper conductive material layer" used in this specification is defined as a layer including copper or copper alloy. Copper alloy seed layer 502 includes a copper metal alloy that facilitates subsequent material deposition thereon. The copper alloy seed layer 502 may include copper and a second metal, such as aluminum, magnesium, titanium, zirconium, tin, other metals, and combinations thereof. The second metal preferably includes aluminum, magnesium, titanium, and combinations thereof, and more preferably includes aluminum. In certain embodiments, the copper alloy seed layer comprises a concentration having a lower limit of about 0.001 atomic percent, about 0.01 atomic percent, or about 0.1 atomic percent and an upper limit of about 5.0 atomic percent, about 2.0 atomic percent, or about 1.0 atomic percent. second metal. Concentrations of the second metal ranging from any lower limit to any upper limit are within the scope of the invention. The concentration of the second metal in the copper alloy seed layer 502 is preferably less than about 5.0 atomic percent to reduce the electrical resistance of the copper alloy seed layer 502 . The term "layer" used in this specification is defined as one or more layers. For example, for a copper alloy seed layer 502 that includes copper and a second metal at a concentration ranging between about 0.001 percent and about 5.0 atomic percent, the copper alloy seed layer 502 may include multiple layers, where the total composition of the multiple layers includes copper and a second metal at a concentration between about 0.001 atomic percent and about 5.0 atomic percent. To illustrate, a copper alloy seed layer 502 comprising a plurality of layers, wherein the total composition of the layers includes copper and a second metal at a concentration between about 0.001 atomic percent and about 5.0 atomic percent, examples may include second metal-containing A first seed layer and a copper-containing second seed layer may include a copper-containing/second metal alloy first seed layer and a copper-containing/second metal alloy second seed layer, or may include a copper-containing/second metal alloy Alloyed first seed layer and copper-containing second seed layer, etc.

The copper alloy seed layer 502 is deposited to a thickness of at least about 5 Angstroms covering the sidewalls of the features, or to a thickness of at least continuous coverage of the sidewalls of the features. In one embodiment, the copper alloy seed layer 502 is deposited in the field region to a thickness between about 10 Angstroms and about 2000 Angstroms, preferably between about 500 Angstroms and about 1000 Angstroms for copper alloy seed layers 502 deposited by physical vapor deposition. Between Angles.

Another embodiment shown in FIG. 5B includes depositing a copper alloy seed layer 512 on the barrier layer 204 of FIG. 2B , depositing a second seed layer 514 on the copper alloy seed layer 512 , and depositing a copper conductive Material layer 516 to fill the feature. Copper alloy seed layer 512 includes a copper metal alloy that facilitates subsequent deposition of material thereon. The copper alloy seed layer 512 may include copper and a second metal, such as aluminum, magnesium, titanium, zirconium, tin, other metals, and combinations thereof. The second metal preferably includes aluminum, magnesium, titanium, and combinations thereof, and more preferably includes aluminum. In certain embodiments, the copper alloy seed layer comprises a concentration having a lower limit of about 0.001 atomic percent, about 0.01 atomic percent, or about 0.1 atomic percent and an upper limit of about 5.0 atomic percent, about 2.0 atomic percent, or about 1.0 atomic percent second metal. Concentrations of the second metal ranging from any lower limit to any upper limit are within the scope of the invention. In one embodiment, the second seed layer 514 includes undoped copper (ie, pure copper). In one aspect, a second seed layer 514 comprising undoped copper is used due to lower resistivity than a copper alloy seed layer 512 of the same thickness, and due to higher resistance to surface oxidation.

The copper alloy seed layer 512 may be deposited to a thickness of less than one monolayer (ie, sub-monolayer thickness or discontinuous layer) on the sidewalls of the feature. In one embodiment, the combined thickness of the copper alloy seed layer 512 and the second seed layer 514 at the field region is between about 10 Angstroms and about 2000 Angstroms, for copper alloy seed layer 512 and second seed layer 512 deposited using physical vapor deposition. The seed layer 514 is preferably between about 500 Angstroms and about 1000 Angstroms.

Another embodiment shown in FIG. 5C includes depositing a first seed layer 523 on the barrier layer 204 of FIG. 2B and depositing a copper conductive material layer 526 on the second seed layer 524 to fill the features. The first seed layer 523 includes a metal selected from the group consisting of aluminum, magnesium, titanium, zirconium, tin, and combinations thereof. Preferably, the first seed layer comprises aluminium. In one embodiment, the second seed layer 514 includes undoped copper (ie, pure copper).

The first seed layer 523 may be deposited to a thickness of less than one monolayer (ie, sub-monolayer thickness or discontinuous layer) on the sidewalls of the feature. In one embodiment the first seed layer is deposited to a thickness of less than about 50 Angstroms sidewall coverage, preferably less than about 40 Angstroms sidewall coverage, to reduce the resistance of the combined seed layer. The combined thickness of the first seed layer 523 and the second seed layer 524 at the field region is between about 10 Angstroms and about 2000 Angstroms, preferably for the first seed layer 523 and the second seed layer 524 deposited by physical vapor deposition. Between about 500 Angstroms and about 1000 Angstroms.

The copper alloy seed layer 502, 512, first seed layer 523 or second seed layer 514, 524 may be deposited by techniques including physical vapor deposition, chemical vapor deposition, atomic layer deposition, electroless deposition, or a combination of these techniques . Typically, if physical vapor deposition techniques are used to deposit the seed layer, the process chamber, such as process chamber 412 as depicted in FIG. 4 , includes a target, such as target 414 , having a composition similar to the metal or metal alloy desired to be deposited. For example, to deposit copper alloy seed layers 502, 512, the target may include copper and a second metal, such as aluminum, magnesium, titanium, zirconium, tin, other metals, and combinations thereof. The second metal preferably comprises aluminum. In certain embodiments, the target includes a second concentration at a concentration having a lower limit of about 0.001 atomic percent, about 0.01 atomic percent, or about 0.1 atomic percent and an upper limit of about 5.0 atomic percent, about 2.0 atomic percent, or about 1.0 atomic percent. Metal. Concentrations of the second metal ranging from any lower limit to any upper limit are within the scope of the invention. In another example, for depositing the first seed layer 523, the target includes a metal selected from the group consisting of aluminum, magnesium, titanium, zirconium, tin, and combinations thereof. If the seed layer is deposited by chemical vapor deposition or atomic layer deposition, a process chamber such as that shown in Figure 1 is suitable for supplying suitable metal precursors of the metal or metal alloy to be deposited.

One exemplary process for depositing a seed layer by physical vapor deposition in a process chamber such as that shown in FIG. 4 involves using a target of the material to be deposited. The processing chamber can be maintained at a pressure of between about 0.1 mTorr and about 10 mTorr. The target may be DC biased at a power of between about 5 kilowatts and about 100 kilowatts. The socket can be RF biased at a power of about 0 and about 1000 watts. The seat may not be heated (ie room temperature).

The layers of copper conductive material 506, 516, 526 may be deposited by electroplating, physical vapor deposition, chemical vapor deposition, electroless deposition, or a combination of these techniques. Preferably, the layers of copper conductive material 506, 516, 526 are deposited by electroplating, since bottom-up growth can be obtained in electroplating processes. An exemplary electroplating method is described in US Patent 6,113,771, entitled "ElectroDeposition Chemistry," issued September 5, 2000, and is incorporated herein by reference to the extent not inconsistent with the present invention.

Copper alloy seed layers such as copper-aluminum seed layers have been observed to have improved adhesion on barrier layers when compared to undoped copper seed layers on barrier layers. Due to the good adhesion of the copper alloy seed layer on the barrier layer, the copper alloy seed layer acts as a good wetting agent for the material deposited thereon. Without wishing to be bound by theory, it is believed that the concentration of copper and other metals in the copper seed layer provides a seed layer with good wetting properties and good electrical properties. It is further believed that since the copper alloy seed layer provides an improved interface for the adhesion of materials thereon, a copper alloy seed layer having a total thickness of less than one monolayer can be used as long as the second seed layer, such as the undoped seed layer, is deposited thereon to provide at least one combined continuous seed layer.

Similarly, metal seed layers such as aluminum seed layers have been observed to provide improved adhesion on barrier layers when compared to non-doped seed layers on barrier layers. Because the metal seed layer has good adhesion on the barrier layer, the metal seed layer acts as a good wetting agent for the material deposited thereon. Without wishing to be bound by theory, it is believed that since the metal layer provides an improved interface for adhesion of materials thereon, such as an undoped copper seed layer deposited on the metal layer, a seed layer such as aluminum having a total thickness of less than one monolayer can be used. Layer metal seed layer.

The seed layers disclosed herein have improved adhesion on the barrier layer and good wettability for materials deposited thereon. Thus, the seed layer improves the potential for agglomeration, dewetting, or the formation of voids in the copper conductive material layer by reducing the possibility of agglomeration, dewetting, or the formation of voids in the copper conductive material layer during subsequent high temperature processing, and under thermal stress during device use. device reliability.

In one aspect, the seed layer can be used with any barrier layer and can be used with barrier layers deposited by any technique. The seed layer can be deposited by any deposition technique. Also, a layer of conductive material, such as a layer of copper conductive material, may be deposited on the seed layer by any deposition technique.

The invention can take advantage of filling windows with opening widths less than about 0.2 microns and having aspect ratios greater than about 4:1, about 6:1, or about 10:1.

The processes disclosed herein can be performed in stand-alone processing chambers, or in multi-chamber processing systems having multiple processing chambers. FIG. 6 is a schematic top view of one example of a multi-chamber processing system 600 suitable for performing the processes disclosed herein. The device is an ENDURA(TM) system and is commercially available from Applied Materials, Inc., of Santa Clara, California. A similar multi-chamber processing system is disclosed in US Patent 5,186,718, issued February 16, 1993, entitled "Stage Vacuum Wafer Processing System and Method" (Tepman et al.), which is incorporated herein by reference to the extent that it does not contradict this disclosure. The specific implementation of the system 600 is used to illustrate the present invention, and should not be used to limit the scope of the present invention.

System 600 generally includes load locks 602 , 604 for transferring substrates into and out of system 600 . Typically, the load locks 602, 604 can "pump down" a substrate introduced into the system 600 since the system 600 is under vacuum. The first robot 610 may transfer substrates between load lock chambers 602 , 604 , process chambers 612 , 614 , transfer chambers 622 , 624 and other chambers 616 , 618 . The second robot 630 may transfer substrates between the processing chambers 632 , 634 , 636 , 638 and the transfer chambers 622 , 624 . Process chambers 612 , 614 , 632 , 634 , 636 , 638 may be eliminated from system 600 if not necessary for a particular process to be performed by system 600 .

In one embodiment, system 600 is configured such that process chamber 634 is suitable for depositing copper alloy seed layer 502 . For example, the processing chamber 634 used to deposit the copper alloy seed layer 502 may be a physical vapor deposition chamber, a chemical vapor deposition chamber, or an atomic layer deposition chamber. The system 600 can further be configured such that the processing chamber 632 is adapted to deposit the barrier layer 204, wherein the copper alloy seed layer 502 is adapted to be deposited on the barrier layer. For example, the processing chamber 632 used to deposit the barrier layer 204 may be an atomic layer deposition chamber, a chemical vapor deposition chamber, or a physical vapor deposition chamber. In a particular embodiment, processing chamber 632 may be an atomic layer deposition chamber, such as the processing chamber shown in FIG. 1 , and processing chamber 634 may be a physical vapor deposition chamber, such as the processing chamber shown in FIG. 4 .

In another embodiment, the system 600 is configured such that the processing chamber 634 is adapted to deposit the copper alloy seed layer 512 and the processing chamber 636 is adapted to deposit the second seed layer 514 on the copper alloy seed layer 512 . For example, the processing chamber 634 for depositing the copper alloy seed layer 512 and/or the processing chamber 636 for depositing the second seed layer may be a physical vapor deposition chamber, a chemical vapor deposition chamber, or an atomic layer deposition chamber. System 600 may further be configured such that process chamber 632 is adapted to deposit barrier layer 204, wherein copper alloy seed layer 512 is deposited on the barrier layer. For example, the processing chamber 632 used to deposit the barrier layer 204 may be an atomic layer deposition chamber, a chemical vapor deposition chamber, or a physical vapor deposition chamber. In a particular embodiment, processing chamber 632 may be an atomic layer deposition chamber, such as the processing chamber shown in FIG. 1 , and processing chambers 634 , 636 may be physical vapor deposition chambers, such as the processing chamber shown in FIG. 4 .

In another embodiment, system 600 is configured such that process chamber 634 is adapted to deposit metal seed layer 523 and such that process chamber 636 is adapted to deposit a second seed layer on metal seed layer 523 . For example, processing chamber 634 for depositing metal seed layer 523 and/or processing chamber 636 for depositing second seed layer 524 may be a physical vapor deposition chamber, a chemical vapor deposition chamber, or an atomic layer deposition chamber. The system can further be configured such that the process chamber 632 is adapted to deposit the barrier layer 204, with the metal seed layer 523 deposited on the barrier layer. For example, the processing chamber 632 used to deposit the barrier layer 204 may be an atomic layer deposition chamber, a chemical vapor deposition chamber, or a physical vapor deposition chamber. In a particular embodiment, processing chamber 632 may be an atomic layer deposition chamber, such as the processing chamber shown in FIG. 1 , and processing chambers 634 , 636 may be physical vapor deposition chambers, such as the processing chamber shown in FIG. 4 .

In one aspect, barrier layer 204 and seed layers (such as copper alloy seed layer 502, copper alloy seed layer 512 and second seed layer 514, or metal seed layer 523 and second seed layer 523 and second seed layer 514) can be performed in a multi-chamber processing system under vacuum layer 524) to prevent air or other impurities from entering the layers and maintain the seed structure on the barrier layer 204.

Other embodiments of the processing chamber 600 are within the scope of the present invention. For example, the location of a particular process chamber on the system may change. In another example, a single processing chamber can be adapted to deposit two different layers.

example

Example 1

A TaN layer was deposited on the substrate by atomic layer deposition to a thickness of approximately 20 Angstroms. A seed layer was deposited by physical vapor deposition on the TaN layer to a thickness of about 100 Angstroms. The seed layer comprises any of the following compositions: 1) undoped copper deposited using a target containing undoped copper, 2) an aluminum concentration of about 2.0 atomic percent deposited using a copper-aluminum target having an aluminum concentration of about 2.0 atomic percent 3) a copper alloy having a tin concentration of about 2.0 atomic percent deposited using a copper-tin target having a tin concentration of about 2.0 atomic percent, or 4) using a copper-tin target having a zirconium concentration of about 2.0 atomic percent The zirconium target deposits a copper alloy containing a zirconium concentration of about 2.0 atomic percent. The resulting substrate was annealed at about 380° C. for a period of about 15 minutes in an ambient of nitrogen (N ₂ ) and hydrogen (H ₂ ).

Scanning electron micrographs show agglomeration of the undoped copper layer after annealing. Copper-zirconium alloys exhibit less agglomeration than non-doped copper. Copper-tin alloys exhibit less agglomeration than copper-zirconium alloys. Copper-aluminum alloys show insignificant agglomeration.

Example 2

Copper-aluminum alloy films containing about 2.0 atomic percent aluminum were deposited on different substrates by physical vapor deposition using a copper-aluminum target having an aluminum concentration of about 2.0 atomic percent. The resulting substrate included 1) a copper-aluminum layer deposited to a thickness of about 50 angstroms on an ALDTaN layer, 2) a copper-aluminum layer deposited to a thickness of about 50 angstroms on a layer of about 100 angstroms of Ta, 3) a layer of 4) a copper-aluminum layer deposited to a thickness of approximately 100 angstroms on a silicon nitride (SiN) layer, and 5) a layer of copper deposited to a thickness of approximately 100 angstroms on a silicon nitride (SiN) layer thick copper-aluminum layer. The resulting substrate was annealed at about 380° C. for a period of about 15 minutes in an ambient of nitrogen (N ₂ ) and hydrogen (H ₂ ). Scanning electron micrographs showed no apparent agglomeration of the copper-aluminum alloys on the various substrates.

Example 3

Using a copper-aluminum alloy target with an aluminum concentration of about 2.0 atomic percent, a copper-aluminum alloy film with an aluminum concentration of about 2.0 atomic percent is deposited on the ALDTaN layer to a thickness of 50 angstroms or 100 angstroms by physical vapor deposition. The resulting substrate is annealed at a temperature of about 380°C, about 450°C, or about 500°C for a period of about 15 minutes in an ambient of nitrogen ( _N2 ) and hydrogen ( _H2 ). Scanning electron micrographs show no apparent agglomeration of the copper-aluminum alloy for substrates annealed at temperatures of about 380°C or about 450°C. Copper-aluminum alloys show some dewetting onset for substrates annealed at temperatures around 500°C.

Example 4

Using a copper-aluminum alloy target with an aluminum concentration of about 2.0 atomic percent, a copper-aluminum alloy film with an aluminum concentration of about 2.0 atomic percent is deposited on the ALDTaN layer to a thickness of 50 angstroms or 100 angstroms by physical vapor deposition. The resulting substrate was annealed at a temperature of about 450° C. for a period of about 30 minutes in an atmosphere of nitrogen (N ₂ ) and hydrogen (H ₂ ). Scanning electron micrographs showed no apparent agglomeration of the copper-aluminum alloy for the substrate annealed at a temperature of about 450°C for a period of 30 minutes.

While the foregoing relates to a preferred embodiment of the invention, other and further embodiments of the invention are conceivable without departing from its essential scope, which is defined by the claims.

Claims (73)

1. A system for processing a substrate comprising: at least one atomic layer deposition barrier chamber for depositing a barrier layer comprising tantalum nitride on a substrate, wherein the at least one atomic layer deposition barrier chamber is connected to a gas panel configured to extract from A first source of which receives a tantalum-containing gas and a nitrogen-containing gas from a second source containing ammonia, wherein the chlorine concentration of the PDMAT is less than or equal to 100 ppm, and the atomic layer deposition barrier chamber is further configured to sequentially provide: Tantalum-containing gases including PDMAT at flow rates between 100 sccm and 1000 sccm for less than or equal to 1 second; purge gas less than or equal to 1 second; Nitrogen-containing gases, including ammonia, having a flow rate between 100 sccm and 1000 sccm of less than or equal to 1 second; and purge gas less than or equal to 1 second; Wherein the deposition thickness of each cycle of the atomic layer deposition barrier chamber is between and between the tantalum nitride layers, and at least one physical vapor deposition metal seed chamber comprising a copper alloy target and configured for depositing a copper alloy seed layer over the barrier layer, wherein the copper alloy target comprises copper and is selected from aluminum, magnesium, titanium, A metal selected from the group consisting of zirconium, tin, and combinations thereof, and the copper alloy target comprises the metal at a concentration between 0.01 atomic percent and 2.0 atomic percent. 2. The system of claim 1, wherein the chlorine concentration of the PDMAT is less than or equal to 30 ppm. 3. The system of claim 2, wherein the chlorine concentration of the PDMAT is less than or equal to 5 ppm. 4. The system of claim 1, wherein the physical vapor deposition metal seed chamber is a high density plasma physical vapor deposition metal seed chamber. 5. The system of claim 1, further comprising one or more transfer chambers for transferring substrates between the ALD barrier chamber and the PVD metal seed chamber. 6. The system of claim 1, wherein the at least one physical vapor deposition metal seed chamber is configured to deposit the copper alloy seed layer directly on the barrier layer comprising tantalum nitride. 7. The system of claim 1, wherein the copper alloy target comprises the metal at a concentration between 0.1 atomic percent and 1.0 atomic percent. 8. The system of claim 1, wherein the gas panel is configured to receive purge gas from a purge gas source. 9. The system of claim 1, wherein the copper alloy target comprises copper and aluminum. 10. The system of claim 1, wherein the copper alloy target comprises copper and titanium. 11. A system for processing a substrate comprising: at least one atomic layer deposition barrier chamber for depositing a barrier layer comprising tantalum nitride on a substrate, wherein the at least one atomic layer deposition barrier chamber is connected to a gas panel configured to extract from A first source of which receives a tantalum-containing gas and a nitrogen-containing gas from a second source containing ammonia, wherein the chlorine concentration of the PDMAT is less than or equal to 100 ppm, and the atomic layer deposition barrier chamber is further configured to sequentially provide: Tantalum-containing gases, including PDMAT, at flow rates between 100 sccm and 1000 sccm for less than or equal to 1 second; purge gas less than or equal to 1 second; Nitrogen-containing gases, including ammonia, having a flow rate between 100 sccm and 1000 sccm of less than or equal to 1 second; and purge gas less than or equal to 1 second; Wherein the deposition thickness of each cycle of the atomic layer deposition barrier chamber is between and between the tantalum nitride layers, at least one physical vapor deposition copper alloy seed chamber containing a copper alloy target and configured for depositing a copper alloy seed layer over the barrier layer, wherein the copper alloy target comprises copper and copper alloys selected from aluminum, magnesium, titanium A metal selected from the group consisting of , zirconium, tin and combinations thereof, and At least one physical vapor deposition undoped copper seed chamber configured for depositing an undoped copper seed layer over the copper alloy seed layer. 12. The system of claim 11, wherein the chlorine concentration of the PDMAT is less than or equal to 30 ppm. 13. The system of claim 12, wherein the chlorine concentration of the PDMAT is less than or equal to 5 ppm. 14. The system of claim 11, wherein the physical vapor deposition copper alloy seed chamber is a high density plasma physical vapor deposition copper alloy seed chamber, and the physical vapor deposition undoped copper seed chamber is a high Density plasma physical vapor deposition undoped copper seed chamber. 15. The system according to claim 11 , further comprising one or more of said ALD barrier chamber, said physical vapor deposition copper alloy seed chamber and said physical vapor deposition undoped copper seed crystal Transfer chamber for transferring substrates between chambers. 16. The system of claim 11, wherein the at least one physical vapor deposition copper alloy seed chamber is configured to deposit the copper alloy seed layer directly on the barrier layer comprising tantalum nitride. 17. The system of claim 11, wherein the copper alloy target comprises the metal at a concentration between 0.001 atomic percent and 5.0 atomic percent. 18. The system of claim 11, wherein the copper alloy target comprises the metal at a concentration between 0.01 atomic percent and 2.0 atomic percent. 19. The system of claim 11, wherein the gas panel is configured to receive purge gas from a purge gas source. 20. The system of claim 11, wherein the copper alloy target comprises copper and aluminum. 21. The system of claim 11, wherein the copper alloy target comprises copper and titanium. 22. A system for processing a substrate comprising: at least one atomic layer deposition barrier chamber for depositing a barrier layer comprising tantalum nitride on a substrate, wherein the at least one atomic layer deposition barrier chamber is connected to a gas panel configured to extract from A first source of which receives a tantalum-containing gas and a nitrogen-containing gas from a second source containing ammonia, wherein the chlorine concentration of the PDMAT is less than or equal to 100 ppm, and the atomic layer deposition barrier chamber is further configured to sequentially provide: Tantalum-containing gases including PDMAT at flow rates between 100 sccm and 1000 sccm for less than or equal to 1 second; purge gas less than or equal to 1 second; Nitrogen-containing gases, including ammonia, having a flow rate between 100 sccm and 1000 sccm of less than or equal to 1 second; and purge gas less than or equal to 1 second; Wherein the deposition thickness of each cycle of the atomic layer deposition barrier chamber is between and between the tantalum nitride layers, at least one physical vapor deposition metal seed chamber comprising a metal target and configured for depositing a metal seed layer over the barrier layer, wherein the metal target comprises metal targets selected from the group consisting of aluminum, magnesium, titanium, zirconium, tin, and the metals selected from the group formed by the combination; and At least one physical vapor deposition undoped copper seed chamber configured for depositing an undoped copper seed layer over the metal seed layer. 23. The system of claim 22, wherein the PDMAT has a chlorine concentration of less than or equal to 30 ppm. 24. The system of claim 23, wherein the chlorine concentration of the PDMAT is less than or equal to 5 ppm. 25. The system of claim 22, wherein the physical vapor deposition metal seed chamber is a high density plasma physical vapor deposition metal seed chamber, and the physical vapor deposition undoped copper seed chamber is a high density plasma Physical vapor deposition undoped copper seed chamber. 26. The system of claim 22, further comprising one or more barrier chambers for said ALD, said PVD metal seed chamber, and said PVD undoped copper seed chamber A transfer chamber for transferring substrates between them. 27. The system of claim 22, wherein the at least one physical vapor deposition metal seed chamber is configured to deposit the metal seed layer directly on the barrier layer comprising tantalum nitride. 28. A system for processing a substrate comprising: at least one atomic layer deposition barrier chamber connected to a gas panel configured to receive a tantalum-containing gas from a first source containing PDMAT and a nitrogen-containing gas from a second source containing a nitrogen precursor, wherein the PDMAT The chlorine concentration is less than or equal to 100ppm, the ALD barrier chamber is further configured to sequentially provide: Tantalum-containing gases, including PDMAT, at flow rates between 100 sccm and 1000 sccm for less than or equal to 1 second; purge gas less than or equal to 1 second; A nitrogen-containing gas including a nitrogen precursor having a flow rate between 100 sccm and 1000 sccm of less than or equal to 1 second; and purge gas less than or equal to 1 second; At least one physical vapor deposition metal seed chamber having a copper alloy target comprising copper and a metal selected from the group consisting of aluminum, titanium, and combinations thereof, wherein the copper alloy target is present at 0.001 atomic percent and 5.0 Concentrations between atomic percent contain said metal; and At least one transfer chamber configured for transferring a substrate between the ALD barrier chamber and the physical vapor deposition metal seed chamber. 29. The system of claim 28, wherein the PDMAT has a chlorine concentration of less than or equal to 30 ppm. 30. The system of claim 29, wherein the PDMAT has a chlorine concentration of less than or equal to 5 ppm. 31. The system of claim 28, wherein the copper alloy target comprises the metal at a concentration between 0.01 atomic percent and 2.0 atomic percent. 32. The system of claim 31, wherein the copper alloy target comprises the metal at a concentration between 0.1 atomic percent and 1.0 atomic percent. 33. The system of claim 31, wherein the copper alloy target comprises copper and aluminum. 34. The system of claim 31 , wherein the copper alloy target comprises copper and titanium. 35. The system of claim 28, wherein the nitrogen precursor is ammonia. 36. A system for processing a substrate comprising: at least one atomic layer deposition chamber for depositing a barrier layer comprising tantalum nitride on a substrate, wherein the at least one atomic layer deposition chamber is connected to a gas panel configured to extract from a compound containing tantalum A first source of which receives a tantalum-containing gas and a nitrogen-containing gas from a second source comprising a nitrogen precursor, the tantalum-containing compound having a chlorine concentration of less than or equal to 100 ppm, and the atomic layer deposition chamber is further configured to sequentially provide: Tantalum-containing gases, including tantalum-containing compounds, at flow rates between 100 sccm and 1000 sccm for less than or equal to 1 second; purge gas less than or equal to 1 second; A nitrogen-containing gas including a nitrogen precursor having a flow rate between 100 sccm and 1000 sccm of less than or equal to 1 second; and less than or equal to 1 second of purge gas; and At least one physical vapor deposition metal seed chamber configured for depositing a copper-containing seed layer on the barrier layer. 37. The system of claim 36, wherein the at least one physical vapor deposition metal seed chamber is a high density plasma physical vapor deposition metal seed chamber. 38. The system of claim 37, further comprising one or more transfer chambers for transferring substrates between the at least one atomic layer deposition chamber and the at least one physical vapor deposition metal seed chamber. 39. The system of claim 36, wherein the tantalum-containing compound is an organometallic precursor of tantalum. 40. The system of claim 39, wherein the organometallic precursor of tantalum is PDMAT. 41. The system of claim 40, wherein the PDMAT has a chlorine concentration of less than or equal to 30 ppm. 42. The system of claim 41, wherein the PDMAT has a chlorine concentration of less than or equal to 5 ppm. 43. The system of claim 40, wherein the nitrogen precursor is ammonia. 44. A system for processing a substrate comprising: at least one atomic layer deposition chamber for depositing a barrier layer comprising tantalum nitride on a substrate, wherein the at least one atomic layer deposition chamber is connected to a gas panel configured to extract from an organic layer comprising tantalum A first source of a metal precursor receives a tantalum-containing gas and a nitrogen-containing gas from a second source containing a nitrogen precursor, wherein the organometallic precursor of tantalum has a chlorine concentration of less than or equal to 100 ppm, and the atomic layer deposition chamber is also configured to in turn provide: Tantalum-containing gases comprising organometallic precursors of tantalum at flow rates between 100 sccm and 1000 sccm for less than or equal to 1 second; purge gas less than or equal to 1 second; A nitrogen-containing gas including a nitrogen precursor having a flow rate between 100 sccm and 1000 sccm of less than or equal to 1 second; and purge gas less than or equal to 1 second; At least one physical vapor deposition metal seed chamber configured for depositing a copper-containing seed layer on the barrier layer. 45. The system of claim 44, wherein the organometallic precursor of tantalum is PDMAT. 46. A system for processing a substrate comprising: at least one atomic layer deposition chamber for depositing a barrier layer comprising tantalum nitride on a substrate, wherein the at least one atomic layer deposition chamber is connected to a gas panel configured to extract from a compound containing tantalum A first source of which receives a tantalum-containing gas and a nitrogen-containing gas from a second source comprising a nitrogen precursor, the tantalum-containing compound having a chlorine concentration of less than or equal to 100 ppm, and the atomic layer deposition chamber is further configured to sequentially provide: Tantalum-containing gases, including tantalum-containing compounds, at flow rates between 100 sccm and 1000 sccm for less than or equal to 1 second; purge gas less than or equal to 1 second; A nitrogen-containing gas including a nitrogen precursor having a flow rate between 100 sccm and 1000 sccm of less than or equal to 1 second; and less than or equal to 1 second of purge gas; and At least one deposition chamber configured for depositing a copper-containing layer on the barrier layer, the deposition chamber selected from the group consisting of a physical vapor deposition chamber, an electroless deposition chamber. 47. The system of claim 46, wherein the at least one deposition chamber is a physical vapor deposition chamber. 48. The system of claim 47, wherein the physical vapor deposition chamber is a high density plasma physical vapor deposition metal seed chamber. 49. The system of claim 48, further comprising one or more transfer chambers for transferring substrates between the at least one atomic layer deposition chamber and the physical vapor deposition chamber. 50. The system of claim 46, wherein the tantalum-containing compound is an organometallic precursor of tantalum. 51. The system of claim 50, wherein the organometallic precursor of tantalum is PDMAT. 52. The system of claim 51, wherein the PDMAT has a chlorine concentration of less than or equal to 30 ppm. 53. The system of claim 52, wherein the PDMAT has a chlorine concentration of less than or equal to 5 ppm. 54. The system of claim 51, wherein the nitrogen precursor is ammonia. 55. A system for processing a substrate comprising: at least one atomic layer deposition chamber for depositing a barrier layer comprising tantalum nitride on a substrate, wherein the at least one atomic layer deposition chamber is connected to a gas panel configured to extract from an organic layer comprising tantalum A first source of a metal precursor receives a tantalum-containing gas and a nitrogen-containing gas from a second source containing a nitrogen precursor, wherein the organometallic precursor of tantalum has a chlorine concentration of 100 ppm or less, the atomic layer deposition barrier chamber is also configured to in turn provide: Tantalum-containing gases comprising organometallic precursors of tantalum at flow rates between 100 sccm and 1000 sccm for less than or equal to 1 second; purge gas less than or equal to 1 second; A nitrogen-containing gas including a nitrogen precursor having a flow rate between 100 sccm and 1000 sccm of less than or equal to 1 second; and less than or equal to 1 second of purge gas; and At least one deposition chamber selected from a physical vapor deposition chamber and an electroless deposition chamber for depositing a copper-containing layer on said barrier layer. 56. The system of claim 55, wherein the organometallic precursor of tantalum is PDMAT. 57. A system for processing a substrate comprising: at least one atomic layer deposition chamber for depositing a barrier layer comprising tantalum nitride on a substrate, wherein the at least one atomic layer deposition chamber is connected to a gas panel configured to extract from a compound containing tantalum A first source of which receives a tantalum-containing gas and a nitrogen-containing gas from a second source comprising a nitrogen precursor, the tantalum-containing compound having a chlorine concentration of less than or equal to 100 ppm, the atomic layer deposition chamber further configured to sequentially provide: Tantalum-containing gases, including tantalum-containing compounds, at flow rates between 100 sccm and 1000 sccm for less than or equal to 1 second; purge gas less than or equal to 1 second; A nitrogen-containing gas including a nitrogen precursor having a flow rate between 100 sccm and 1000 sccm of less than or equal to 1 second; and less than or equal to 1 second of purge gas; and at least one physical vapor deposition metal seed chamber configured for depositing a metal seed layer on the barrier layer, wherein the metal seed layer comprises copper and metals selected from aluminum, magnesium, titanium, zirconium, tin, and Metals selected from the group consisting of their alloys and combinations. 58. The system of claim 57, said tantalum-containing compound having a chlorine concentration of less than or equal to 30 ppm. 59. The system of claim 58, said tantalum-containing compound having a chlorine concentration of less than or equal to 5 ppm. 60. A method of preparing a substrate structure for copper metallization comprising the steps of: During an atomic layer deposition process, a thickness less than or equal to The tantalum nitride barrier layer: Tantalum-containing gases including PDMAT with a flow rate between 100 sccm and 1000 sccm for less than or equal to 1 second, where the PDMAT has a chlorine concentration of less than or equal to 100 ppm; purge gas less than or equal to 1 second; Nitrogen-containing gases, including ammonia, having a flow rate between 100 sccm and 1000 sccm of less than or equal to 1 second; and less than or equal to 1 second of purge gas; and maintaining the temperature of the heater between 100°C and 300°C during the atomic layer deposition process; and then A seed layer comprising copper and a metal selected from the group consisting of aluminum, magnesium, zirconium, and combinations thereof is deposited over the tantalum nitride barrier layer. 61. The method of claim 60, wherein the tantalum nitride barrier layer has a sidewall coverage less than or equal to 62. A method of preparing a substrate structure for electroplating copper comprising the steps of: During an atomic layer deposition process, a thickness less than or equal to The blocking layer: Tantalum-containing gases including PDMAT with a flow rate between 100 sccm and 1000 sccm for less than or equal to 1 second, where the PDMAT has a chlorine concentration of less than or equal to 100 ppm; purge gas less than or equal to 1 second; Nitrogen-containing gases, including ammonia, having a flow rate between 100 sccm and 1000 sccm of less than or equal to 1 second; and less than or equal to 1 second of purge gas; and maintaining the temperature of the heater between 100°C and 300°C during the atomic layer deposition process; and A seed layer comprising copper and aluminum is deposited over the barrier layer. 63. The method of claim 62, wherein the barrier layer has a thickness less than or equal to 64. The method of claim 62, wherein the seed layer comprises a copper alloy seed layer comprising aluminum at a concentration between 0.001 atomic percent and 5.0 atomic percent. 65. The method of claim 64, wherein the copper alloy seed layer includes aluminum at a concentration between 0.01 atomic percent and 2.0 atomic percent. 66. The method of claim 64, wherein the copper alloy seed layer includes aluminum at a concentration between 0.1 atomic percent and 1.0 atomic percent. 67. The method of claim 62, wherein the seed layer comprises a first seed layer deposited over the barrier layer and a second seed layer deposited over the first seed layer layer. 68. The method of claim 67, wherein the first seed layer comprises a copper alloy seed layer having a concentration of aluminum in the copper alloy seed layer between 0.001 atomic percent and 5.0 atomic percent, and The second seed layer includes undoped copper. 69. The method of claim 68, wherein the copper alloy seed layer includes aluminum at a concentration between 0.01 atomic percent and 2.0 atomic percent. 70. The method of claim 68, wherein the copper alloy seed layer comprises aluminum at a concentration between 0.1 atomic percent and 1.0 atomic percent. 71. The method of claim 67, wherein the first seed layer comprises aluminum having a thickness between sub-monolayer and and the second seed layer includes undoped copper. 72. The method of claim 62, wherein the barrier layer comprises tantalum nitride. 73. The method of claim 62, wherein the seed layer is deposited using a process selected from the group consisting of physical vapor deposition, chemical vapor deposition, atomic layer deposition, and electroless deposition.