KR20060052683A - Method and apparatus for generating a precursor for a semiconductor processing system - Google Patents

Abstract

Embodiments of the present invention are directed to an apparatus for generating a precursor for a semiconductor processing system (320). The apparatus includes a canister (300) having a sidewall (402), a top portion and a bottom portion. The canister (300) defines an interior volume (438) having an upper region (418) and a lower region (434). In one embodiment, the apparatus further includes a heater (430) partially surrounding the canister (300). The heater (430) creates a temperature gradient between the upper region (418) and the lower region (434). Also claimed is a method of forming a barrier layer from purified pentakis (dimethylamido) tantalum, for example a tantalum nitride barrier layer by atomic layer deposition.

Description

Method and apparatus for generating a precursor for a semiconductor processing apparatus {METHOD AND APPARATUS FOR GENERATING A PRECURSOR FOR A SEMICONDUCTOR PROCESSING SYSTEM}

The present invention generally relates to depositing a barrier layer on a semiconductor substrate.

Reliable creation of ultrafine and smaller features is one of the key technologies for the next generation of ultra-large scale integrated circuits (VLSI) and ultra high density integrated circuits (ULSI) in semiconductor devices. However, as circuit technical knowledge shrinks, additional requirements have arisen in the processing capacity due to the decreasing dimensions of the interconnects in the VLSI and ULSI. The multilevel interconnects at the heart of this technology require accurate handling of high aspect ratio features such as vias and other interconnects. Reliable formation of such interconnects is critical to the success of VLSI and ULSI and the constant effort to increase the circuit density and quality of individual substrates.

As the circuit density increases, the dielectric materials between them as well as the widths of the vias, contacts and other features decrease to ultrafine dimensions (dimensions smaller than about 0.20 micrometers or less), while the dielectric Since the thickness of the layers remains substantially constant, the aspect ratios of the features, ie the height / width of the features, increase. Many conventional deposition processes have difficulty filling ultrafine structures, the aspect ratio of which exceeds 4: 1 and specifically the aspect ratio exceeds 10: 1. Therefore, considerable efforts and research are underway on the formation of voids and seamless formation with high aspect ratios.

Currently, copper and copper alloys have been selected as metals for ultra-fine interconnect technologies because they have lower resistivity than aluminum (1.7 μΩ · cm compared to 3.1 μΩ · cm of aluminum), and high current transfer This is because it has a capacity and a significantly higher electromigration resistance. These properties are very important to support the high current density and increased device speed seen at high integration levels. Moreover, copper has thermal conductivity and is available even in high purity conditions.

Copper metallization can be accomplished by various techniques. Typical methods generally include physical vapor deposition of a barrier layer to a feature, physical vapor deposition of a copper seed layer to the barrier layer, and electrical transfer of a layer of copper conductive material to the copper seed layer to fill the feature. Plating. Finally, the deposited layers and dielectric layers are planarized by chemical mechanical polishing (CMP) or the like to form conductive interconnect features.

However, one problem with the use of copper is that copper diffuses into silicon, silicon dioxide, and other dielectric materials that can degrade the density of devices. Therefore, barrier layers of the same shape have become extremely important in preventing copper diffusion. Tantalum nitride has been used as a barrier material to prevent copper from diffusing into the underlying layers. However, chemicals used in depositing barrier layers, such as pentakis (dimethylamido) tantalum (PDMAT; Ta [NH ₂ (CH ₃ ) ₂ ] ₅ ), may contain impurities, which may cause semiconductor devices to Defects can be caused in the manufacture of these and the process yield can be reduced. Therefore, a need exists for a method of depositing a barrier layer from a high-purity precursor.

Embodiments of the invention relate to neglect to create a precursor for a semiconductor processing system. Such a device includes a canister having side walls, top and bottom. The canister defines an internal volume having an upper region and a lower region. The apparatus further includes a heater surrounding the canister. The heater creates a temperature gradient between the upper region and the lower region.

In the manner in which the mentioned features of the invention are retained and better understood, the detailed description of the invention summarized above will be further detailed with reference to the embodiments of the invention shown in the accompanying drawings. However, it is to be understood that the accompanying drawings are merely exemplary embodiments of the present invention, and therefore should not be regarded as limiting the present invention, and that embodiments having other equal effects are possible.

1 is a schematic cross-sectional view of one embodiment of a barrier layer formed on a substrate by atomic layer deposition (ALD).

2A-2C illustrate an embodiment of alternating chemisorption of monolayers of tantalum containing compound and nitrogen containing compound on an exemplary portion of a substrate.

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

4A is a section side view of one embodiment of a gas generating canister;

4B is a section top view of the gas generating canister of FIG. 4A.

5 is a section view of another embodiment of a gas generating canister.

6 is a section side view of another embodiment of a gas generating canister.

7 is a section view of a canister surrounded by a canister heater in accordance with one embodiment of the present invention.

8 is a section view of a canister including a plurality of solid particles in accordance with one embodiment of the present invention.

9 is a cross-sectional view of a number of silos extending from the lower portion of the canister to the upper region in accordance with one embodiment of the present invention.

10 is a top view of a number of silos extending from the lower portion of the canister to the upper region in accordance with one embodiment of the present invention.

1 is a schematic cross-sectional view of one embodiment of a substrate having a dielectric layer 102 and a barrier layer 104 deposited thereon. Depending on the processing step, the substrate 100 may be a silicon semiconductor substrate, or another layer of material that has been formed on the substrate. Dielectric layer 102 may include contact holes or vias 102H extending to an oxide side, silicon oxide, carbon-silicon-oxide, fluoro-silicon, porous dielectric, or exposed surface portion 102T of substrate 100. It may be another suitable dielectric formed and patterned to provide. For clarity, the substrate 100 is referred to as any workpiece on which film processing is performed, and the substrate structure 150 is formed of any material layers formed on the substrate 100, such as the dielectric layer 102 as well as the substrate. Used to indicate. It will be understood by those skilled in the art that the present invention may be used in dual damask process processing. Barrier layer 104 is formed against substrate structure 150 of FIG. 1A by atomic layer deposition (ALD). The barrier layer preferably comprises a tantalum nitride layer.

In one embodiment, atomic layer deposition of the tantalum nitride barrier layer includes sequentially providing the tantalum containing compound and the nitrogen containing compound to the processing chamber. By sequentially providing the tantalum containing compound and the nitrogen containing compound, monolayers of the tantalum containing compound and a single layer of the nitrogen containing compound are alternately chemisorbed onto the substrate structure 150.

2A-2C illustrate alternate chemoadsorption of monolayers of tantalum containing compound and nitrogen containing compound on an exemplary portion of substrate 200 in an integrated circuit fabrication step, more particularly barrier layer forming step. In FIG. 2A, a monolayer of tantalum containing compound is chemisorbed onto the substrate 200 by introducing a pulse of tantalum containing compound 205 into the processing chamber.

Tantalum containing compound 205 typically includes tantalum atoms 210 having one or more reactive species 215. In one embodiment, the tantalum containing compound is pentadimethylamino-tantalum (PDMAT; Ta (NMe ₂ ) ₅ ). PDMAT has advantages for many reasons. PDMAT is relatively stable. In addition, the PDMAT has a suitable vapor pressure that facilitates delivery. In particular, PDMAT can be produced with low halide content. The halide content of the PDMAT should be produced with a halide content of 100 ppm or less. Contrary to theoretical limitations, organic nitrogen precursors with low halide content are beneficial because halides such as chlorine integrated in the barrier layer can invade the copper layer deposited thereon.

Thermal decomposition of the PDMAT during production can lead to impurities in the PDMAT article which are then used to form the tantalum nitride barrier layer. Such impurities may include compounds such as CH ₃ NTa (N (CH ₃ ) ₂ ) ₃ and ((CH ₃ ) ₂ N) ₃ Ta (NCH ₂ CH ₃ ). In addition, due to its reactivity with water, tantalum oxoamide compounds are present in PDMAT products. Preferably, tantalum oxo amide compounds are removed from the PDMAT by sublimation. For example, tantalum oxo amide compounds are removed in a bubbler. PDMAT products preferably have less than about 5 ppm chlorine. In addition, the levels of lithium, iron, fluorine, bromine and iodine should be minimized. Most preferably, the total level of impurities is about 5 ppm or less.

The tantalum containing compound may be provided as a gas or may be provided for the purpose of a carrier gas. Examples of carrier gases that can be used include, but are not limited to, helium (He), argon (Ar), nitrogen (N ₂ ), and hydrogen (H ₂ ).

After monolayers of tantalum containing compound are chemisorbed onto the substrate 200, excess tantalum containing compound is removed from the processing chamber by injecting purge gas into the processing chamber. Examples of purge gases that can be used include, but are not limited to, helium (He), argon (Ar), nitrogen (N ₂ ), and hydrogen (H ₂ ) and other gases.

Referring again to FIG. 2B, after the processing chamber is purged, a pulse of nitrogen containing compound 225 is introduced into the processing chamber. Nitrogen containing compound 225 may be provided alone or may be provided for the purpose of a carrier gas. Nitrogen containing compound 225 may include nitrogen atoms 230 having one or more reactive species 235. The nitrogen-containing compound preferably contains ammonia gas (NH ₃ ). Other nitrogen containing compounds may be used, where N _X H _Y (X and Y are integers, for example hydrazine (N ₂ H ₄ )), dimethyl hydrazine ((CH ₃ ) ₂ N ₂ H ₂ ), t-butylhydrazine ( C ₄ H ₉ N ₂ H ₃ ), phenylhydrazine (C ₆ H ₅ N ₂ H ₃ ), other hydrazine derivatives, nitrogen plasma sources (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 ), ethylazide (C ₂ H ₅ N ₃ ), and other suitable gases, including but not limited to Does not. Carrier gases can be used to deliver nitrogen containing compounds if desired.

A monolayer of nitrogen containing compound 225 may be chemisorbed onto the monolayer of tantalum containing compound 205. During atomic-layer deposition (ALD) the composition and structure of the precursors on the surface are not precisely known. Contrary to theoretical limitations, the chemisorbed monolayer of nitrogen containing compound 225 reacts with the monolayer of tantalum containing compound 205 to form tantalum nitrogen layer 209. Reactive species 215 and 235 form byproducts 240 that are transported from the substrate surface by a vacuum system.

After the monolayer of nitrogen containing compound 225 has been chemisorbed onto the monolayer of tantalum containing compound, any excess nitrogen containing compound is removed from the processing chamber by introducing another purge gas pulse into the processing chamber. Then, as shown in FIG. 2C, the sequential deposition of the tantalum nitrogen layer, in which the monolayers of the tantalum containing compound and the monolayers of the nitrogen containing compound are alternately chemisorbed, is repeated if desired, until the desired tantalum nitrogen thickness is achieved. .

In FIGS. 2A-2C, the formation of tantalum nitrogen layer begins with chemisorption of a monolayer of tantalum containing compound onto the substrate followed by chemisorption of the monolayer of nitrogen containing compound. Alternatively, tantalum nitrogen layer formation can begin by chemisorbing a monolayer of the nitrogen containing compound onto the substrate followed by chemisorbing the monolayer of the tantalum containing compound. Moreover, in alternative embodiments, pump vacuum only between pulses of reactive gases may be used to prevent mixing of reactive gases.

The duration for each pulse of tantalum containing compound, nitrogen tantalum compound, and purge gas is variable and depends on the deposition capacity used as well as the vacuum capacity of the vacuum system coupled to the chamber. For example, (1) low chamber gas pressures will require long pulse times; (2) low gas flow rates will require longer time to raise and stabilize the chamber pressure and will require longer pulse times; (3) The large-volume chamber will take longer to charge and will take longer to stabilize the chamber pressure, requiring longer pulse times. Similarly, the time between each pulse is also variable and depends on the volume capacity of the processing system as well as the volume capacity of the vacuum system coupled to the chamber. In general, the monolayers of tantalum containing compounds or nitrogen containing compounds should be long enough to allow chemisorption of the compound monolayers. In general, the pulse time of the purge gas should be long enough to remove reactive byproducts and / or any residues remaining in the processing chamber.

In general, a pulse time of about 1.0 seconds or less for a tantalum containing compound, and a pulse time of about 1.0 seconds or less for a nitrogen containing compound is typically sufficient to alternately chemisorb monolayers on a substrate. A pulse time of about 1.0 second or less of the purge gas is typically sufficient to remove reactive byproducts as well as any residual material remaining in the processing chamber. Of course, longer pulse times can be used to ensure chemisorption of tantalum containing compounds and nitrogen containing compounds and to ensure the removal of reactive byproducts.

During atomic layer deposition, the substrate can be maintained at or below the thermal decomposition temperature of the selected tantalum containing compound. Exemplary heater temperature ranges used with tantalum containing compounds identified herein are from about 20 ° C to about 500 ° C at chamber pressures of about 100 Torr or less, preferably 50 Torr or less. When the tantalum containing gas is PDMAT, the heater temperature is preferably about 100 ° C to about 300 ° C, more preferably about 175 ° C to about 250 ° C. In other embodiments, it should be understood that other temperatures may be used. For example, temperatures above the thermal decomposition temperature can be used. However, the temperature must be chosen such that at least 50% of the deposition action is achieved by chemisorption processes. In other embodiments, temperatures above the thermal decomposition temperature may be used such that the amount of decomposition during each precursor deposition is limited so that the growth mode is similar to the atomic layer growth mode.

One exemplary process for depositing a tantalum nitrogen layer by atomic layer deposition in a processing chamber is 1.0 second or less at a flow rate between about 100 sccm and about 1000 sccm, preferably between about 200 sccm and about 500 sccm. Providing pentadimethylamino-tantalum (PDMAT) during the time period, ammonia for 1.0 seconds or less at a flow rate between about 100 sccm and about 1000 sccm, preferably between about 200 sccm and about 500 sccm Providing a purge gas for a time period of 1.0 second or less at a flow rate between about 100 sccm and about 1000 sccm, preferably between about 200 sccm and about 500 sccm. The heater temperature is preferably maintained at about 100 ° C. to about 300 ° C. at a chamber pressure between about 1.0 to about 5.0 Torr. The process provides a layer of tantalum nitrogen of about 0.5 kPa to about 1.0 kPa per cycle. Sequential shifts are repeated until the desired thickness is achieved.

3 is a schematic cross-sectional view of an exemplary embodiment of a processing system 320 that may be used to form one or more barrier layers by atomic layer deposition in accordance with the present invention. Of course, other processing systems may also be used.

에칭 챔버들, PRODUCER

화학적 기상 증착 챔버들, 및 ENDURA

물리적 기상 증착 챔버들을 포함한다.The processing system 320 generally includes a processing chamber 306 coupled to the gas delivery system 304. Process chamber 306 may be any suitable process chamber, such as, for example, those available from Applied Materials, Inc. of Santa Clara, California. Exemplary processing chambers, among others, are DPS CENTURA

Etching Chambers, PRODUCER

Chemical vapor deposition chambers, and ENDURA

Physical vapor deposition chambers.

Gas delivery system 304 generally controls the speed and pressure when various processes and inert gases are delivered to processing chamber 306. The number and types of processes and other gases delivered to the processing chamber 306 are generally selected based on the processes performed in the combined processing chamber 306. For simplicity it is contemplated in FIG. 3 that additional gas delivery circuits may be used, although a single gas delivery circuit is shown in gas delivery system 304.

Gas delivery system 304 is generally coupled between carrier gas source 302 and processing chamber 306. Carrier gas source 302 may be a local or remote pipe or central facility source that provides carrier gas for the entire installation. Carrier gas source 302 generally provides a carrier gas such as argon, nitrogen, helium or other inert or non-reactive gas.

Gas delivery system 304 generally includes a flow rate controller 310 coupled between carrier gas source 302 and process gas source canister 300. The flow rate controller 310 may be a proportional valve, a modulation valve, a needle valve, and flow controllers. One flow controller 310 that may be used is available from Sierra Instruments, Inc. of Monterrey, CA.

Source canister 300 is typically coupled and positioned between first and second valves 312 and 314. In one embodiment, the first and second valves 312 and 314 are coupled to the source canister 300 and the removal of the valves 312 and 314 together with the source canister 300 from the gas delivery system 304. It is secured with a separate fitting (not shown) to facilitate. The third valve 316 is positioned between the second valve and the processing chamber 306 to prevent contaminants from entering the processing chamber 306 after the source canister 300 is removed from the gas delivery system 304. do.

4A and 4B are section views of one embodiment of source canister 300. Source canister 300 generally includes a sealed container having an ampoule or housing 420 adapted to hold the fructus materials 414 through which a process (or other) gas is sublimed or vaporized. Can be generated by Some solid precursor materials 414 that can generate process gas in the source canister 300 through a sublimation process include inter alia difluoride xenon, carbonyl nickel, hexa-carbonyl tungsten, and pentakis (dimethylami). And tantalum (PDMAT). Some fluid precursor materials 414 capable of producing process gas in the source canister 300 through vaporization include, inter alia, tetrakis (dimethylamino) titanium (TDMAT), tertbutylimitotris (diethyl). Amino) tantalum (TBTDET) and pentakis (ethylmethylamino) tantalum (PEMAT). Since housing 420 is generally made from a material that is substantially inert to precursor materials 414 and a gas produced from those materials, the constituent material may vary based on the gas produced.

The housing 420 can have any number of geometrical forms. In the embodiment shown in FIGS. 4A and 4B, the housing 420 includes a cylindrical sidewall 402 and a bottom surface 432 sealed by the lid 404. Lead 404 may be coupled to sidewall 402 by welding, bonding, adhesives or a weak bonding method. Alternatively, the coupling between sidewall 402 and lid 404 may have seals, o-rings, gaskets, and the like positioned therebetween to prevent leakage from source canister 300. Sidewall 402 may alternatively include other geometric shapes, such as, for example, hollow square tubes.

Inlet port 406 and outlet port 408 are formed through the source canister to allow gas to flow into and out of the source canister 300. Ports 406 and 408 may be formed through leads 404 and / or sidewalls 402 of source canister 300. The ports 406, 408 are generally sealable such that the interior of the source canister 300 is separated from the surrounding environment while the source canister is removed from the gas delivery system 304. In one embodiment, the valves 312, 314 are removed from the gas delivery system 304 (shown in FIG. 3) for refilling the precursor material 414 or replacing the source canister 300. Sealedly coupled to ports 406 and 408 to prevent leakage from source canister 300. Paired disconnect fittings 436A, 436B may be coupled to valves 312, 314 to facilitate removal and replacement of source canister 300 to / from gas delivery system 304. Valves 312 and 314 are typically ball valves or other positive seal valves, by which the source canister 300 is removed from the effectively loaded and recirculated system while simultaneously filling the gas delivery system 304, Minimize potential leakage from the source canister 300 during transfer or mating. Alternatively, the source canister 300 may be refilled through a refill port (not shown), such as a small tube with VCR readings located on the lid 404 of the source canister 300.

Source canister 300 has an internal volume 438 having an upper region 418 and a lower region 434. Lower region 434 of source canister 300 is at least partially filled with precursor materials 414. Alternatively, fluid 416 can be added to solid precursor material 414 to form slurry 412. Precursor materials 414, fluid 416, or premixed slurry 412 may be removed from lead 404 or introduced into source canister 300 through one of ports 406 and 408. . Fluid 416 is such that fluid 416 is non-reacting with precursor materials 414, precursor materials 414 are insoluble in the fluid, and fluid 416 precursor precursors 414. Has a negligible vapor pressure, and the ratio of the vapor pressure of the solid precursor material 414, for example hexa-carbonyl tungsten, to the vapor pressure of the fluid 416 is at least 10 ³ .

Works로부터 이용가능한 IKAMAG

REO 이다. 대안으로써, 슬러리(412)는 혼합기, 버블러등과 같은 다른 수단에 의해 교반될 수 있다.The precursor materials 414 mixed with the fluid 416 may be occasionally agitated to keep the precursor materials 414 suspended in the fluid 416 within the slurry 412. In one embodiment, precursor material 414 and fluid 416 are agitated by magnetic paddle 440. Magnetic stir 440 includes a magnetic motor 442 located below the bottom surface 432 of the source canister 300, and a magnetic fill 444 located in the lower region 434 of the source canister 300. do. The magnetic motor 442 operates to rotate the magnetic fill 444 inside the source canister 300, thereby mixing the slurry 412. Magnetic fill 44 should have an outer coating material that is non-reactive with precursor materials 414, fluid 416, or source canister 300. Suitable magnetic mixers are commercially available. One example of a suitable magnetic mixer is IKw, Wilmington, North Carolina, USA.

IKAMAG available from Works

REO. Alternatively, slurry 412 may be agitated by other means, such as a mixer, bubbler, and the like.

Agitation of the fluid 416 may lead to fluid 416 particles that are carried in the carrier gas and are sent to the processing chamber 306. To prevent such fluid 416 particles from reaching the processing chamber 306, an oil trap 450 may optionally be coupled to the outlet port 408 of the source canister 300. The oil trap 450 includes a body 452 including a plurality of baffles 454 present between the baffles, which extend beyond the centerline 456 of the oil trap body 452 to extend the source canister ( Inclined to at least slightly downward toward 300). The baffles 454 cause gas to flow toward the processing chamber 306 to allow the tortuous path around the baffles 454 to flow. The surface area of the baffles 454 provides a large area area exposed to the flowing gas, and oil particles that can be loaded in the gas adhere to the area. The downward angle of the baffles 454 causes any oil accumulated in the oil trap to flow downward and back into the source canister 300.

Source canister 300 includes at least one baffle 410 located within upper region 418 of source canister 300. The baffle 410 is positioned between the inlet port 406 and the outlet port 408 to create an extended average flow path, whereby a direct (ie, straight) flow of carrier gas is caused by the inlet port of the outlet port 408. Prevent entry into 406. This has the effect of increasing the average residence time of the carrier gas in the source canister 300 and increasing the amount of sublimation or vaporization precursor gas carried by the carrier gas. In addition, the baffles 410 adjust the carrier gas to the entire exposed surface of the precursor material 414 located in the source canister 300 to allow for repeated gas generation characteristics and efficient consumption of the precursor materials 414. To ensure.

The number, spacing and shape of the baffles 410 may be selected to adjust the source canister 300 for optimal generation of precursor gas. For example, a fairly large number of baffles 410 may be selected to provide higher carrier gas velocities in the precursor material 414, and the shape of the baffles 410 may result in more efficient use of the precursor material. Can be configured to control the consumption of precursor material 414.

The baffle 410 may be attached to the sidewall 402 or the lead 404, or the baffle 410 may be prefabricated insert design to fit inside the source canister 300. In one embodiment, the baffles 410 disposed in the source canister 300 include five rectangular plates made of the same material as the sidewall 402. 4B, the baffles 410 are welded or otherwise secured to the sidewall 402 to be parallel to each other. The baffles 410 are secured between the opposite sides of the source canister in an alternating manner such that a sinuous extended average flow path is created. Also, the baffles 410 are positioned between the outlet port 408 and the lid 404 when positioned on the sidewall 402, and there is no air between the baffles 410 and the lid 404. . The baffles 410 extend at least partially further into the lower region 434 of the source canister 300, thereby defining an extended average flow path for the carrier gas flowing through the upper region 418.

Optionally, inlet tube 422 may be located in internal volume 438 of source canister 300. The tube 422 is coupled to the inlet port 406 of the source canister 300 by the first end 424 and ends at the second end 426 in the upper region 418 of the source canister 300. The tube 422 injects a carrier gas into the upper region of the source canister 300 at a location near precursor materials 414 or slurry 412.

Precursor materials 414 produce the precursor gas at a predefined temperature and pressure. Sublimed or vaporized gas from precursor materials 414 accumulates in the upper region 418 of the source canister 300 and enters through the inlet port 406 and exits the outlet port 408. Are swept away and transferred to the processing chamber 306. In one embodiment, precursor materials 414 are heated to a predefined temperature by resistive heater 430 located near sidewall 402. Alternatively, the precursor materials 414 may be raised by other means, such as a cartridge heater disposed in the upper region 418 or lower region 434 of the source canister 300, or upward of the carrier gas inlet port 406. It can be heated by preheating the carriage gas by means of a located heater (not shown). For maximum uniform heat distribution over the entirety of the slurry 412, the fluid 416 and baffles 410 should be good thermal conductors.

According to another embodiment of the present invention, a plurality of solid beads or particles 810 having high thermal conductivity, such as aluminum nitride or bromine nitride, may be used instead of the fluid 416 as shown in FIG. have. Such solid particles 810 are used to transfer more heat than the fluid 416 from the sidewall of the canister 800 to the precursor materials 414. Solid particles 810 have the same properties as fluid 416, do not react with precursor materials 414, are insoluble, and have negligible vapor pressure when compared to precursor materials 414. As such, the solid particles 810 are configured to effectively transfer heat from the sidewall of the canister 800 to the central portion of the canister 800, thereby resulting in more precursor material utilization during sublimation or vaporization. Solid particles 810 are also degassed to clean contaminants, water vapor, etc., before being deposited into canister 800.

In one example of the mode of operation, the lower region 434 of the source canister 300 is at least partially filled with a mixture of hexa-carbonyl tungsten and diffusion pump oil to form the slurry 412. The slurry 412 is maintained at a pressure of about 5 Torr and heated to a temperature of about 40 ° C. to about 50 by a resistive heater 430 located near the source canister 300. Carrier gas in the form of arcon flows from the inlet port 406 to the upper region 418 at a rate of about 400 standard cc / min. Argon flows through the baffles 410 through the extended average flow path defined by the winding path, before exiting the source canister 300 through the outlet port 408, thereby allowing the top of the source canister 300 to flow. The average residence time of argon in region 418 is increased and advantageous. The increased residence time in the source canister 300 advantageously increases the saturation level of the sublimed hexa-carbonyl vapors in the carrier gas. Moreover, the tortuous path through the baffles 410 favors the carrier gas with the exposed substantially entire surface area of the precursor material 414 for uniform consumption of the precursor material 414 and generation of the precursor gas. Expose

7 illustrates another embodiment for heating precursor materials 414. More specifically, FIG. 7 shows a section view of a canister 700 surrounded by canister heater 730, which can be a lower region 434 of canister 700 and an upper region 418 of canister 700. Is configured to create a temperature gradient between, where the lower region 434 is the coldest region and the upper region 418 is the hottest region. The temperature gradient may be about 5 ° C to about 15 ° C. Solid precursor materials generally tend to accumulate and condense in the coldest region of canister 700, and canister heater 730 allows solid precursor materials 414 to have lower region 434 of canister 700. And to increase the predictability of where the solid precursor materials 414 will condense, and the temperature of the solid precursor materials 414. Canister heater 730 is a heating element 750 located inside canister heater 730 such that the entire canister 700, including upper region 418 and lower region 434, is heated by canister heater 730. ). The heating element 750 near the upper region 418 is configured to generate more heat than the heating element 750 near the lower region 434, such that the canister heater 730 is lower than the lower region 434 and the upper region. It causes the temperature gradient to be generated between the regions 418. In one embodiment, the heating element 750 is configured such that the temperature in the upper region 418 is about 5 ° C. to about 15 ° C. higher than the temperature in the lower region 434. In another embodiment, the heating element 750 is configured such that the temperature in the lower region 418 is about 60 ° C. and the temperature at the sidewall of the canister 700 is about 65 ° C. The power of the heating element 730 may be about 600 watts at the 208 VAC input.

Canister heater 730 may also include a cold plate 720 located on the bottom surface of canister heater 730 to further ensure that the coldest region of canister 700 is the bottom region 434. It is ensured that the solid precursor materials 414 condense in the lower region 434. Cold plate 720 may also be annular. Moreover, valves 312 and 314, oil trap 450, inlet port 406 and outlet port 408 may be heated by resistive heating tape. Since the upper region 418 is configured to have a higher temperature than the lower region 434, the baffles 418 can be used to transfer heat from the upper region 418 to the lower region 434, whereby Canister heater 730 maintains the desired temperature gradient.

9 is a section view of a number of silos 910 extending from the lower surface portion 432 of the canister 700 to the upper region 418. 10 is a top view of the passages 910 extending from the lower surface portion 432 of the canister 700 to the upper region 418. The silos 910 are configured to reduce the temperature gradient of the precursor materials 414, thereby allowing the temperature inside the precursor materials 414 to be maintained substantially uniform. The silos 910 may extend slightly above the upper surface of the precursor materials 414 and the fluid 416 at the lower surface portion 432. Silos 910 may be in the form of posts or pins. Silos 910 may be made from a heat-conductive material, such as stainless steel, aluminum, and the like.

9 further illustrates an inlet tube 422 located in the interior volume 438 of the source canister 700. The tube 422 is coupled to the inlet port 406 of the source canister 700 by the first end 424, ending at the second end 426 in the upper region 418 of the source canister 700. The tube 422 injects carrier gas into the upper region 418 of the source canister 700 at a location close to the precursor materials 414 or slurry 412. The second end 426 may be adapted to direct the amount of gas towards the side wall 402, thereby preventing gases from flowing directly (linear or visible) through the canister 700 between the ports 406, 408. Will result in an extended average flow path.

5 is a section view of another embodiment of a canister 500 for producing a process gas. Canister 500 includes sidewall 402, lid 404, and bottom surface 432 that enclose internal volume 438. At least one of the lid 404 or sidewall 402 includes an inlet port 406 and an outlet port 408 for the inlet and outlet of the gas. The internal volume 438 of the canister 500 is separated into the upper region 418 and the lower region 434. Precursor materials 414 at least partially fill lower region 434. Precursor materials 414 may be in solid, fluid or slurry form and are adapted to produce process gas by sublimation and / or vaporization.

The tube 502 is disposed in the interior volume 438 of the canister 500, and the gas flow inside the canister 500 is adapted to travel away from the precursor materials 414, thereby It prevents outflowing gases from directly impacting the precursor materials 414 and allows particulates to float in the air and be transported through the outlet port 408 to the processing chamber 306. The tube 502 is coupled to the inlet port 406 at the first end 504. The tube 502 extends from the first end 504 to the second end 526A, which is located in the upper region 418 in the precursor materials 414. The second end 526A may be adapted to direct the flow of gas to the sidewall 402, whereby a direct (linear or visible) flow of gas through the canister 500 passes between the ports 406, 408. To create an extended average flow path.

In one embodiment, the outlet 506 of the second end 526A of the tube 502 is oriented at an angle of about 15 degrees to about 90 degrees with respect to the central axis 508 of the canister 500. In another embodiment, the tube 502 has a “J” -shaped second end 526B, the second end of which leads the flow of gas exiting the outlet 506 into the lid 404 of the canister 500. ). In another embodiment, the tube 502 has a capped second end 526C having a plug or cap 510 that closes the end of the tube 502. The capped second end 526C has at least one opening 528 formed on the side of the tube 502 near the cap 510. The gas exiting the openings 528 is typically perpendicular to the central axis 508 and directed away from precursor materials 414 disposed in the lower region 434 of the canister 500. Optionally, at least one baffle 410 (indicated by the dashed lines) as described above may be located inside the chamber 500 and cooperate with any of the embodiments of the tube 502 described above. Can be used.

In one embodiment of the operating mode, the lower region 434 of the canister 500 may be at least partially filled with a mixture of hexa-carbonyl tungsten and diffusion pump oil to form the slurry 412. Slurry 412 is maintained at a pressure of about 5 Torr and heated to a temperature of about 40 to about 50 ° C. by resistive heater 430 located near canister 500. Carrier gas in the form of argon flows into the upper region 418 through the inlet port 406 and the tube 502 at a rate of about 200 standard cc / min. The second end 526A of the tube 502 allows carrier gas to flow in an average flow path extending away from the outlet port 408, thereby causing the average residual of argon in the upper region 418 of the canister 500. The time is advantageously increased and prevents direct flow of carrier gas on the precursor materials 414 to minimize particulate generation. Increased residence time in canister 500 advantageously increases the saturation level of sublimated hexa-carbonyl tungsten in the carrier gas while simultaneously reducing particulate production, improving production yields, and conserving solid sources, Reduce downstream contaminants.

6 is a section view of another embodiment of a canister 600 to produce precursor gas. Canister 600 includes sidewall 402, lid 404, and bottom surface 432 that enclose internal volume 438. At least one of the lid 404 or sidewall 402 has an inlet port 406 and an outlet port 408 for the inlet and outlet of the gas. Inlet and outlet ports 406 and 408 are valves 312 and 314 fitted with paired disconnect fittings 436A and 436B to facilitate removal of canister 600 from gas delivery system 304. ) Is combined. Optionally, the oil trap 450 is coupled between the outlet port 408 and the valve 314 to capture any oil particulates that may be present in the gas flowing into the processing chamber 306.

The internal volume 438 of the canister 600 is divided into an upper region 418 and a lower region 434. Precursor materials 414 and fluid 416 at least partially fill lower region 434. A tube 602 is disposed in the interior volume 438 of the canister 600, directing the first gas stream inside the canister 600 away from the precursor material and directing the second gas stream F ₂ through the mixture. Adapted to face. The flow F ₁ is much more than the flow F ₂ . Flow F ₂ is configured to act as a bubbler and is large enough to agitate the mixture of precursor material and fluid, but particles or droplets of precursor materials 414 or fluid 416 may enter the air. It is not big enough to float. Therefore, this embodiment advantageously stirs the mixture of precursor material and fluid while at the same time the particulates generated by the gas flowing out of the tube 602 directly impinge on the precursor materials cause the outlet port 408 to float. Transfer to the process chamber 306 is minimized.

The tube 602 is coupled to the inlet port 406 at the first end 604. Tube 602 extends from first end 604 to second end 606, the second end being in the lower region 434 of canister 600 in the mixture of precursor material and fluid. The tube 602 has an opening 608 located in the upper region 418 of the canister 600, which directs the first gas flow F ₁ to the side wall 402 of the canister 600. . The tube 600 has a restriction 610 located in the upper region 438 of the canister 600 located below the opening 608. Restriction 610 serves to reduce the second gas flow F ₂ flowing into slurry 412 towards second end 606 of tube 602. By adjusting the amount of restriction, the relative velocities of the first and second gas flows F ₁ and F ₂ can be adjusted. This coordination serves at least two purposes. First, the second gas stream F ₂ can be minimized to provide sufficient agitation to maintain floating or mixing of the precursor materials 414 in the fluid 416 while at the same time generating particulates in the processing chamber 306. And potential contaminants can be minimized. Second, the first gas flow F ₁ may be adjusted to maintain the required flow volume needed to provide the required amount of vaporized and / or sublimated vapors from the precursor materials 414 to the processing chamber 306. Can be.

Optionally, at least one baffle 410 as described above may be disposed inside canister 600 and may be used in cooperation with any of the embodiments of tube 602 described above. .

Although described above according to preferred embodiments of the present invention, other embodiments of the present invention are possible without departing from the basic spirit of the present invention, and the concept of the present invention is determined only by the following claims.

Claims (45)

A method of filling one or more features on a substrate, the method comprising: Depositing a barrier layer on the substrate, the barrier layer being formed from purified pentacis (dimethylamido) tantalum having impurities of 5 ppm or less; Depositing a seed layer against the barrier layer; And Depositing a conductive layer on the seed layer Charging method of features comprising a. The method of claim 1, Removing at least a portion of tantalum oxo amides and sublimating the pentakis (dimethylamido) tantalum to form the purified pentakis (dimethylamido) tantalum. The method of claim 1, And the conductive layer comprises copper. The method of claim 1, And the barrier layer is formed by atomic layer deposition. The method of claim 1, Wherein said impurities are selected from the group consisting of chromium, lithium, iron, fluorine, bromine, iodine, and combinations thereof. The method of claim 1, By depositing a barrier layer from the purified pentakis (dimethylamido) tantalum, the conductive layer having fewer defects than the conductive layer formed for the barrier layer formed from the unpurified pentakis (dimethylamido) tantalum Method for charging features characterized in that it is generated. A method of depositing a tantalum nitrogen barrier layer on a substrate, Introducing purified pentakis (dimethylamido) tantalum into the processing chamber having a substrate disposed therein to form a tantalum containing layer on the substrate-the purified pentakis (dimethylamido) tantalum is about 5 ppm Or less than or equal to impurities; And Introducing a nitrogen containing compound into the processing chamber to form a nitrogen containing layer on the substrate Barrier layer deposition method comprising a. The method of claim 7, wherein And the substrate has a temperature of about 20 ° C to about 500 ° C. The method of claim 7, wherein And wherein said processing chamber has a pressure of about 100 Torr or less. The method of claim 7, wherein And wherein said impurities are selected from the group consisting essentially of chromium, lithium, iron, fluorine, bromine, iodine, and combinations thereof. The method of claim 7, wherein And the nitrogen-containing compound comprises ammonia gas. The method of claim 7, wherein The nitrogen-containing compound is selected from the group consisting of ammonia, hydrazine, dimethyl hydrazine, t-butylhydrazine, phenylhydrazine, 2,2-azisobutane, ethylazide, and derivatives thereof. Way. The method of claim 7, wherein And the barrier layer is formed by atomic layer deposition. The method of claim 7, wherein The temperature of the substrate is selected so that 50% or more of the barrier layer deposition is made by chemisorption. The method of claim 7, wherein And the purified pentakis (dimethylamido) tantalum is sublimed prior to entering the process chamber. The method of claim 7, wherein Removing at least a portion of the pentakis (dimethylamido) tantalum when forming a tantalum containing layer on the substrate. Purified pentacis (dimethylamido) tantalum with impurities of about 5 ppm or less. The method of claim 17, Purified pentacis (dimethylamido) tantalum, wherein the impurities are selected from the group consisting of tantalum oxo amide, chlorine, lithium, iron, fluorine, bromine, iodine, and combinations thereof. The method of claim 18, The purified pentakis (dimethylamido) tantalum is characterized in that it is sublimed to reduce tantalum oxoamides therein. An apparatus for generating a precursor for a semiconductor processing system, A canister having sidewalls, tops, and bottoms, the canister defining an internal volume having a top region and a bottom region; And A heater surrounding the canister, the heater creating a temperature gradient between the upper region and the lower region; Precursor generation device comprising a. The method of claim 20, Wherein said temperature gradient is from about 5 ° C to about 15 ° C. The method of claim 20, And the lower region has a lower temperature than the upper region. The method of claim 22, And wherein the lower region has a temperature of about 5 ° C. to about 15 ° C. lower than the upper region. The method of claim 20, And the heater is located near a side wall of the canister. The method of claim 20, And the heater is positioned around an outer portion of the canister. The method of claim 25, A heater located around the outer portion of the canister is configured to generate more heat in the upper region of the canister. The method of claim 20, And a cooling plate positioned near the lower surface portion of the canister. The method of claim 20, And the canister includes a heat transfer medium connecting the upper region to the lower region. The method of claim 28, And said heat transfer medium is at least one baffle extending from said upper portion to said lower region. The method of claim 20, And at least one silo extending from the lower surface portion of the canister to the upper region. The method of claim 30, Wherein said at least one silo is at least one of a post and a pin. The method of claim 20, A precursor material at least partially filling the lower region of the canister; And A plurality of solid particles intermixed with the precursor material—the solid particles are non-reactive with the precursor material, have negligible vapor pressure over the precursor material, are insoluble in the precursor material, Configured to transfer heat from the sidewall of the canister- Precursor generation apparatus further comprising a. The method of claim 32, A precursor material at least partially filling the lower region of the canister; And At least one silo extending from the lower surface portion of the canister to the upper region Precursor generation apparatus further comprises a. The method of claim 33, wherein Wherein said at least one silo is configured to reduce a temperature gradient inside said precursor material. An apparatus for generating a precursor for a semiconductor processing system, A canister defining an internal volume having an upper region and a lower region; A precursor material at least partially filling the lower region of the canister; And A gas flow inlet adapted to inject carrier gas into the canister in a direction away from the precursor materials Precursor generation device comprising a. 36. The method of claim 35 wherein And the gas flow inlet pipe is adapted to generate a non-linear flow of gas into the upper region of the canister. The method of claim 36, The linear flow is adapted to produce an increased saturation level of gas in the upper region of the canister. 36. The method of claim 35 wherein And the gas flow inlet pipe extends from an upper region of the canister to a lower region of the canister. The method of claim 38, And the gas flow inlet pipe is adapted to provide a first gas flow to the upper region of the canister. The method of claim 39, And the gas flow inlet pipe is adapted to provide a second gas flow to the lower region of the canister. The method of claim 38, And the gas flow inlet pipe comprises a restricting portion. 42. The method of claim 41 wherein And the gas flow inlet pipe includes at least one opening in front of the restriction. The method of claim 42, And the opening is adapted to provide a non-linear flow of gas to the upper region of the canister. The method of claim 40, Wherein said second gas flow into said lower region is adapted to maintain suspension of said precursor materials. The method of claim 40, And the second gas stream is adapted to maintain a total gas flow volume.

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