KR20070015958A - Apparatuses and methods for atomic layer deposition of hafnium-containing high-? dielectric materials - Google Patents

Abstract

Embodiments of the present invention provide a method for depositing a dielectric material over a substrate during a vapor deposition process, such as atomic layer deposition (ALD). In one example, the method includes sequentially depositing a hafnium oxide material over the substrate by exposing the substrate to a hafnium precursor and an oxidizing gas. In another example, hafnium silicate material is deposited by sequentially exposing the substrate to a process gas and an oxidizing gas containing the hafnium precursor and the silicon precursor. The oxidizing gas contains water vapor formed by flowing an oxygen source gas and a hydrogen source gas through the steam generator.

Description

Apparatus and Method for Atomic Layer Deposition of Hafnium-Containing High-ｋ Dielectric Materials {APPARATUSES AND METHODS FOR ATOMIC LAYER DEPOSITION OF HAFNIUM-CONTAINING HIGH-ｋ DIELECTRIC MATERIALS}

Embodiments of the present invention generally relate to methods and apparatus for depositing materials on substrates, and more particularly to methods and apparatus for depositing high-k dielectric materials by vacuum deposition processes.

In the semiconductor processing field, flat panel processes or other electronic device processes and vapor deposition processes play an important role in depositing materials on circuit boards. As the appearance of electronic devices continues to shrink and the density of equipment increases, the size and aspect ratio of the features become larger. For example, feature sizes of 0.07 μm and aspect ratios of 10 or more are currently under consideration. Therefore, conformal deposition of materials is becoming increasingly important to make these devices.

Conventional chemical vapor deposition (CVD) has proven to be effective for aspect ratios and appearance up to 0.15 μm, but further techniques for deposition are required for the appearance of other devices. A technique of great interest at present is atomic layer deposition (ALD). During the ALD process the reactant gas is sequentially entered into the process chamber containing the circuit board. Typically, the first reactant enters the process chamber and is absorbed by the circuit board surface. The second reactant enters the process chamber and reacts with the first reactant to form a deposition material. Usually a purge step takes place between each reactant gas release. The purge step may be continuous purge with a carrier gas or pulse purge between reactant gas releases.

It is known in the art to oxidize metal and silicon precursors during the ALD process to form high-k dielectric materials. Ozone or oxygen atoms are common oxidants or oxidation sources for ALD processes. Due to the radical state of ozone and oxygen atoms, low process temperatures can be conveniently maintained during the deposition process while forming dielectric materials. While high reactivity at low temperatures is a property of radical oxidants, undesirable side reactions occur frequently throughout the process chamber to form contaminants on the circuit board. Alternatively, water or oxygen can be used as the oxidation source to form the dielectric material during the ALD process. However, due to the not-so-high reactivity of water or oxygen, ALD processes typically require slower flow rates, longer exposure periods, and higher temperatures than radical oxygen sources. In addition, ALD processes that use water or oxygen require an extended purge period after each oxidant addition, thus increasing manufacturing throughput. In addition, slower flow rates and higher temperatures usually increase contaminants on the circuit board surface.

Vapor oxidation processes have been used to passivate or oxidize metals or silicon materials during conventional CVD processes. In one example, steam is produced by boiling water contained in an auxiliary vessel and then plumbed into the process chamber. In another example, hydrogen gas and oxygen gas are supplied to a process chamber preheated at high temperature. Water vapor produced in both examples reacts with the metal surface or silicon surface to form a dielectric material such as metal oxide or silicon oxide. While the aforementioned steam oxidation process can produce water vapor that is effective for use during the CVD process, the steam produced is not suitable for use during the ALD process. Water vapor obtained in this steam oxidation process can cause contaminants on the circuit board surface and can, to a small extent, control the process temperature or the contents of the oxidized water vapor. In addition, ALD processes may require immediate access to reactants of consistent composition that must be delivered to the process chamber in a quantitative manner.

Therefore, there is a need for equipment and processes for depositing dielectric materials that can produce oxidizing gases even at low temperatures, control the composition of oxidizing gases and deposited dielectric materials, and reduce process duration and minimize contamination.

In one embodiment, a method is provided for forming a material comprising hafnium on a circuit board located in a process chamber. This process involves exposing the circuit board to a hafnium precursor to form a layer containing hafnium thereon, purifying the process chamber, exposing the hafnium containing layer to oxidizing gas to form a hafnium oxide material thereon, and then purifying the process chamber. It includes. For example, a silicon oxide material exposes a circuit board to a silicon precursor to form a silicon containing layer thereon, and then purifies the process chamber, exposes the circuit board to oxidizing gas to form a silicon oxide material thereon, and then purifies the process chamber. Is deposited over the hafnium oxide material. The method further utilizes an oxidizing gas comprising water vapor formed by flowing a hydrogen source gas and an oxygen source gas into a steam generator. The steam generator has a catalyst comprising palladium, platinum, nickel, iron, chromium, ruthenium, rhodium or compounds or alloys thereof. The hydrogen source gas and the oxygen source gas may be diluted by adding another gas. For example, a shaping gas comprising about 5% by volume of hydrogen in about nitrogen may be used as the hydrogen source gas. In some examples, an oxygen source gas excess is provided to the steam generator to provide an oxidizing gas with oxygen rich steam. In another example, the circuit board is exposed to oxidizing gas during the pre-soak process after depositing a hafnium containing material or other dielectric material.

In another embodiment, a method of depositing a hafnium containing material over a circuit board during an atomic layer deposition process is provided. It locates the circuit board in the process chamber and flows the hydrogen source gas and the oxygen source gas to a steam generator to produce oxidizing gas including water vapor, and subsequently exposes the circuit board to a process gas containing oxidizing gas and hafnium precursor. Forming a hafnium-containing material thereon. In some examples, the process gas includes secondary precursors such as silicon precursors or aluminum precursors. The process gas may be formed by mixing a hafnium precursor and another gas including at least a secondary precursor and supplying each gas including the precursors in the process chamber. Alternatively, the process gas may be formed by evaporating a reaction mixture comprising at least a hafnium precursor and a secondary precursor. The deposited hafnium containing material may include hafnium oxide, hafnium silicate, hafnium silicon oxynitride, hafnium oxynitride, hafnium aluminate or derivatives thereof, compounds, and the like.

In another embodiment, a method of forming a dielectric material over a circuit board during an atomic layer deposition process is provided. This places the circuit board in the process chamber and sequentially exposes the circuit board to at least one precursor, such as oxidizing gas and hafnium precursor, zirconium precursor, silicon precursor, aluminum precursor, tantalum precursor, titanium precursor, lanthanum precursor or compounds thereof. Process. Steam may be generated by flowing a hydrogen source gas and an oxygen source gas to a steam generator. Examples of dielectric materials formed during the deposition process include hafnium oxide, hafnium silicate, zirconium oxide, lanthanum oxide, lanthanum silicate, tantalum oxide, tantalum silicate, titanium oxide, titanium silicate, aluminum oxide, aluminum silicate, silicon oxide or derivatives thereof or These compounds are included. In one example for forming a hafnium silicate material, the circuit board is sequentially exposed to a process gas comprising an oxidizing gas, a hafnium precursor, and a silicon precursor. In another example, the circuit board is sequentially exposed to hafnium precursor, oxidizing gas, silicon precursor and again oxidizing gas.

In another embodiment, a method of forming a dielectric stack including hafnium on a circuit board is provided. This includes forming at least one hafnium oxide layer and at least one hafnium silicate layer. This process sequentially exposes the circuit board to a first process gas comprising an oxidizing gas and a hafnium precursor to form a first hafnium containing material thereon, and then a second process comprising the circuit board comprising an oxidizing gas and a hafnium precursor. Exposing to a gas to form a second hafnium containing material over the first hafnium containing material. In one example, the first process gas also includes a silicon precursor. The method further includes forming an oxidizing gas including water vapor by flowing the hydrogen source gas and the oxygen source gas to the steam generator.

The above-mentioned features of the present invention can be understood in detail, and a more specific description of the invention, the above briefly summarized description, can be seen by way of example by way of example and these are shown in the accompanying drawings. The accompanying drawings are only intended to illustrate exemplary embodiments of the invention and are not intended to limit the scope of the invention, the invention may accept other equivalent effective embodiments.

1 shows a process sequence for depositing a hafnium-containing material by an ALD process according to the described embodiment.

2A shows a schematic diagram of a configured process system according to the described embodiment.

2B shows a schematic diagram of a steam generator system according to the described embodiment.

3 shows a process sequence for depositing a hafnium-containing material by an ALD process according to another embodiment described.

4 shows a process sequence for depositing a hafnium-containing material by an ALD process according to another described embodiment.

5A-5E illustrate part of the pulsing sequence for hafnium and silicon precursors during an ALD process according to the described embodiment.

6 shows a schematic cross-sectional view of a process chamber that can be used during a deposition process in accordance with the described embodiment.

7 shows a schematic cross-sectional view of another process chamber that may be used during the deposition process according to the described embodiment.

8 shows a schematic cross-sectional view of another process chamber that may be used during the deposition process according to the described embodiment.

9A-9B show schematic diagrams of thermally insulating liners that may be used with the process chamber in accordance with the described embodiment.

10 shows a schematic diagram of a process chamber lid assembly that may be used during the deposition process in accordance with the described embodiment.

The present invention provides a method for depositing hafnium-containing and other high-k dielectric materials on a substrate surface by an atomic layer deposition (ALD) process. In one aspect, the ALD process is performed by sequentially pulsing hafnium precursor and oxidizing gas into the ALD process chamber, thereby forming a hafnium-containing material. The oxidizing gas contains water vapor generated from a water vapor generator (WVG) system coupled to the ALD process chamber. WVG systems generate oxidizing gases at low temperatures (eg <500 ° C.) by exposing the hydrogen source gas and the oxygen source gas to the catalyst. The composition of the oxidizing gas can be precisely controlled to provide steam enriched in various proportions of oxygen or hydrogen. The ALD process, which uses the WVG system to make water vapor, has a fast process that increases the basic control of the composition of the deposited dielectric material, the minimum contaminants on the substrate, and the manufacturing throughput.

fair

1 illustrates an exemplary process sequence 100 for forming a hafnium-containing material such as hafnium oxide in accordance with an embodiment of the present invention. The substrate is loaded into a process chamber capable of performing cyclical deposition, and process conditions are adjusted (step 110). Process conditions may include temperature, chamber pressure, and gas flow rate of the substrate or process chamber. The substrate may be exposed to an optional pre-soak process and purge prior to beginning the ALD process cycle (step 115). The substrate is exposed to a pulse of hafnium precursor, either alone or with the carrier gas, into the process chamber for a time ranging from about 0.1 seconds to about 5 seconds (step 120). The pulse of purge gas then enters the process chamber (step 130) thereby removing or purging any residual hafnium precursor or by-products. A pulse of oxidizing gas is then introduced into the process chamber (step 140). The oxidizing gas may comprise a mixture of various oxidizing elements such as water vapor and oxygen. In addition, a pulse of purge gas enters the process chamber (step 150) thereby removing or purging any residual oxidizing gas or by-products. Suitable carrier gas or purge gas may include helium, argon, nitrogen, hydrogen, forming gas, oxygen or a combination thereof.

As used herein, “pulse” is intended to refer to the amount of a particular compound, which compound is introduced intermittently or not continuously into the reaction zone of the process chamber. The amount of a particular compound in each pulse can vary over time and depends on the duration of the pulse. The duration of each pulse can vary, depending on a number of factors such as, for example, the volume capacity of the process chamber employed, the vacuum system connected thereto and the volatility / reactivity of the particular compound. As used herein, "half-reaction" refers to an exposure step, followed by a removal step. The exposing step provides for introducing a reactant into the process chamber and for chemically reacting or absorbing the reactant on a substrate contained therein, such as a pulse of a process gas containing the reactant. The purge step provides for the removal of reaction by-products or excess reactants from the chamber that introduces the gas (eg purge gas or carrier gas), the installation of a vacuum system and the discharge of the mixture thereof.

Referring to step 160, after each deposition cycle (steps 120-150), a layer of hafnium-containing material, such as hafnium oxide, is deposited over the substrate. In general, each deposition cycle forms a layer having a thickness in the range of about 1 ms to about 10 ms. Depending on certain instrument requirements, subsequent deposition cycles may be required to deposit hafnium-containing materials having the desired thickness. As such, the deposition cycles (steps 120-150) may be repeated to obtain a predetermined thickness of the hafnium-containing material. Process sequence 100 may then stop at step 170 as indicated. Hafnium oxide material formed by the deposition process has the chemical formula HfO _x . Hafnium oxide may have the molecular formula but the hafnium oxide HfO ₂ by the constant process conditions (e.g. time, temperature, or precursor) may be less oxidized as HfO _{1 .8.} Preferably, hafnium oxide is deposited by the process herein with a molecular formula of HfO ₂ or an oxygen: hafnium concentration of less than 2.

The substrate may be exposed to a pretreated or presoak process, thereby finishing the substrate surface with various functional groups, as depicted during step 115. As described herein, useful functional groups prior to starting the deposition process are hydroxyl (OH), alkoxy (OR, R = Me, Et, Pr or Bu), hydroxyl (OX, X = F, Cl, Br or I), Halides (F, Cl, Br or I), oxygen radicals and amino (NR or NR ₂ , R = H, Me, Et, Pr or Bu). The pretreatment process may expose the substrate to the reactants, which are NH3, B2H5, SiH4, SiH5, H2O, HF, HCl, O2, O3, H2O, H2O2, H2, Atom-H, Atom-N, Atom-O , Alcohols, amines, derivatives thereof or combinations thereof. The functional group can provide a base for allowing incoming chemical precursors to adhere onto the substrate surface. The pretreatment process may expose the substrate surface to the reactants for a cycle in the range of about 1 second to about 2 minutes, preferably in the range of about 5 seconds to about 60 seconds.

In one embodiment, the presoak process may include selectively exposing the substrate to an oxidizing gas containing water vapor generated from the WVG system. The presoak process provides a hydroxyl finished functional group on the substrate surface that acts with a precursor containing an amino-type ligand (eg TDEAH, TDMAH, TDMAS, or Tris-DMAS) during subsequent exposure. During the presoak process, the substrate surface is immersed in an oxidizing gas containing water vapor for a time ranging from about 3 seconds to about 90 seconds, preferably from about 5 seconds to about 60 seconds, more preferably from about 10 seconds to about 30 seconds. May be exposed. After the soak process, the process chamber is generally purged with a carrier gas or purge gas, thereby removing any volatile byproducts and excess oxidizing gas therein. In an example of forming a hafnium-containing material, the substrate surface may be exposed for about 9 seconds to an oxidizing gas containing water vapor generated from the WVG system. The process chamber is then purged for about 6 seconds and the ALD process cycle begins by providing a pulse of TEDAH or TDMAH containing process gas. In another example, such as to form a silicon containing material, the substrate surface may be exposed for about 15 seconds to an oxidizing gas containing water vapor generated from the WVG system. The process chamber is then purged for about 10 seconds and the ALD process cycle is initiated by providing a pulse of process gas containing TDMAS or Tri-DMAS.

The ALD process is generally performed in the process chamber at a pressure in the range of about 1 Torr or about 100 Torr, preferably about 1 Torr or about 20 Torr, more preferably about 1 Torr or about 10 Torr. The temperature of the substrate is generally maintained in the range of about 70 ° C to about 1000, preferably about 100 ° C to about 650 ° C, more preferably about 250 ° C to about 500 ° C.

During step 120, the hafnium precursor is introduced into the process chamber at a ratio in the range of about 5 standard cubic centimeters per minute (sccm) to about 200 sccm. Hafnium precursors are generally introduced at a total flow rate ranging from about 50 sccm to about 1000 sccm with a carrier gas such as nitrogen. The hafnium precursor can be pulsed into the process chamber at a rate in the range of about 0.1 seconds to about 10 seconds, depending on the particular process conditions, desired composition of the hafnium precursor or deposited hafnium-containing material. In one embodiment, the hafnium precursor is pulsed into the process chamber at a ratio in the range of about 1 second to about 5 seconds, for example about 3 seconds. In another embodiment, the hafnium precursor is pulsed into the process chamber at a rate in the range of about 0.1 seconds to about 1 second, for example about 0.5 seconds. In one example the hafnium precursor is preferably hafnium tetrachloride (HfCl ₄ ). In another embodiment, the hafnium precursor is preferably a tetrakis (dialkylamino) hafnium compound, such as tetrakis (diethylamino) hafnium ((Et ₂ N) ₄ Hf or TDEAH).

Hafnium precursor is generally distributed into process chamber 280 by introducing a carrier gas through an ampoule 282 containing a hafnium precursor, as shown in FIG. 2A. Ampoule 282 may include an ampoule, bubble, cartridge, or other container used to disperse or contain a chemical precursor. Suitable ampoules, such as the PROE-VAPTM, are available from Advanced Technology Materials in Danbury, Connecticut. Ampoule 282 is in fluid communication with process chamber 280 by conduit 283. Conduit 283 may be a tube, pipe, line, hose, or other conduit known in the art. In addition, the ampoule 282 is spaced 284 from the process chamber 280. The spacing 284 is generally less than about 2 meters, preferably less than about 1.25 meters, and more preferably less than about 0.7 meters. The spacing 284 can be minimized, thereby maintaining a constant hafnium precursor flow. In addition, the conduit 283 may be straight or bent, and the conduit 283 is preferably less curved and straight if possible. Conduit 283 may be stacked with heating tape to maintain a predetermined temperature. The temperature of the ampoule 282 is maintained at a temperature remaining in the hafnium precursor within a temperature such as in the range of about 20 to about 300 ° C. In one example ampoule 282 contains HfCl ₄ at a temperature in the range of about 150 ° C to about 200 ° C.

In one embodiment, ampoule 282 may be part of a liquid delivery system containing injector valve system 281. The injector valve system 281 is connected by conduits 283 to the ampoule 282 and the process chamber 280. The source of carrier gas is generally connected to the injector valve system 281 (not shown). Ampoule 282 containing a liquid precursor (eg, TDEAH, TDMAH, TDMAS or Tris-DMAS) may be pressured to thereby deliver the liquid precursor to injector valve system 281. In general, the ampoule 282 containing the liquid precursor may be pressured at a pressure in the range of about 138 kPa (about 20 psi) to about 414 kPa (about 60 psi) and is about 100 ° C. or less, preferably about 20 ° C. to about 60 ° C. It can be heated to a temperature in the range of. The injector valve system 281 combines the liquid precursor with the carrier gas, thereby forming a precursor that is injected into the process chamber 280. The carrier gas may comprise nitrogen, argon, helium, hydrogen or a combination thereof and the carrier may be preheated to a temperature in the range of about 85 ° C to about 150 ° C. Suitable injector valves are available from Horiba-Stec in Kyoto, Japan.

During step 140, the oxidizing gas enters the process chamber 280 at a flow rate in the range of about 0.05 sccm to about 100 sccm, preferably in the range of about 0.5 sccm to about 100 sccm. The oxidizing gas is pulsed into the process chamber 280 at a rate in the range of about 0.05 seconds to about 10 seconds, preferably about 0.08 seconds to about 3 seconds, more preferably about 0.1 seconds to about 2 seconds. In one embodiment, the oxidizing gas is pulsed at a rate in the range of about 1 second to about 5 seconds, for example about 1.7 seconds. In another embodiment, the oxidizing gas is pulsed at a rate in the range of about 0.1 seconds to about 3 seconds, for example about 0.5 seconds.

The oxidizing gas can be made from a steam generator (WVG) system 286, which is in fluid communication with the process chamber 280 by conduits 287. Fittings 212, 214 may be used to link conduits 287 into process chamber 280 or into WVG system 286. Suitable fittings are available from Fujikin, USA. Conduit 287 is generally in fluid communication with process chamber 280 via an ALD valve assembly. Conduit 287 may be a tube, pipe, hose or line made of metal (eg stainless steel or aluminum), rubber or plastic (eg PTFE). In one embodiment, a pipe made of stainless steel 316L is used as conduit 287. WVG system 286 generates ultra high purity water vapor by the catalytic reaction of a hydrogen source gas (eg H ₂ ) and an oxygen source gas (eg O ₂ ) at low temperatures (eg <500 ° C.). Hydrogen and oxygen source gases flow into the WVG system 286 at flow rates ranging from about 5 sccm to about 200 sccm, preferably from about 10 sccm to about 100 sccm. In general, the flow rates of oxygen and hydrogen source gas are adjusted independently, thereby having no hydrogen or hydrogen source gas and no oxygen or oxygen source gas in the outflow of the oxidizing gas.

Oxygen source gases useful for generating oxidizing gases containing water vapor include oxygen (O 2), atomic oxygen (O), ozone (O 3), nitro oxide (N 2 O), nitrile oxide (NO), nitrogen dioxide (NO 2) , Dinitrogen pentoxide (N 2 O 5), hydrogen peroxide (H 2 O 2), derivatives thereof, or combinations thereof. Hydrogen source gases useful for generating steam containing oxidizing gases include hydrogen (H 2), atomic hydrogen (H), shaping gas (N 2 / H 2), ammonia (NH 3), hydrocarbons (eg CH 4), alcohols (eg CH 3 OH), derivatives thereof or combinations thereof. The carrier gas may flow with an oxygen source gas or a hydrogen source gas and may include N 2, He, Ar, or a combination thereof. Preferably the oxygen source gas is oxygen or nitros oxide and the hydrogen source gas is 5% by volume of hydrogen in a hydrogen or forming gas, nitrogen.

The hydrogen source gas and the oxygen source gas can be diluted with a carrier gas, thereby providing sensitive control of water vapor in the oxidizing gas during the deposition process. In one embodiment, a slow steam flow rate (about <10 sccm water vapor) may be desirable to complete the chemical reaction during the ALD process, thereby forming a hafnium-containing material or other dielectric material. Slow steam flow rates dilute the water vapor concentration in the oxidizing gas. Diluted water vapor is the concentration that oxidizes the absorbed precursor on the substrate surface. Thus, the slow steam flow rate minimizes purge time after steam exposure, thereby increasing the manufacturing throughput. In addition, slow steam flow rates reduce the formation of particulate contaminants by avoiding undesirable interactions. A mass flow controller (MFC) can be used to control the hydrogen source gas at a flow rate of about 0.5 sccm, producing a flow of water vapor at a flow rate of about 0.5 sccm. Thus, a dilute hydrogen source gas (e.g., shaping gas) can be used in the WVG system, thereby achieving a slow steam flow rate. In one example, a hydrogen source gas containing 5% hydrogen forming gas and having a flow rate of about 10 sccm delivers water vapor from the WVG system at a flow rate of about 0.5 sccm. In alternative embodiments, fast steam flow rates (about> 10 sccm water vapor) may be desirable to complete the chemical reaction during the ALD process and form hafnium-containing materials or other dielectric materials. For example, about 100 sccm of hydrogen gas delivers about 100 sccm of water vapor.

The shaping gas may be selected at a hydrogen concentration in the range of about 1% to about 95% by volume of the carrier gas, such as argon or nitrogen. In one aspect, the hydrogen concentration of the shaping gas ranges from about 1% to about 30% by volume of the carrier gas volume, preferably from about 2% to about 20%, more preferably from about 3% to about 10%, and The gas may contain about 5% hydrogen and about 95% nitrogen. In another embodiment the hydrogen concentration of the shaping gas ranges from about 30% to about 90% by volume of the carrier gas, preferably from about 40% to about 90%, more preferably from about 50% to about 85%, eg For example, the molding gas may contain about 80% hydrogen and about 20% nitrogen.

In one example, a WVG system is used to form a hydrogen source gas containing 5% hydrogen (95% nitrogen) at a flow rate of about 10 sccm and an oxidizing gas containing oxygen at a flow rate of about 9.8 sccm and water vapor at a flow rate of about 0.5 sccm. To accommodate an oxygen source gas (eg O ₂ ) at a flow rate of about 10 sccm. In another example, the WVG system contains an oxygen source gas at a flow rate of about 10 sccm and a 5% hydrogen forming gas at a flow rate of about 20 sccm to form an oxidizing gas containing oxygen at a flow rate of about 1 sccm and oxygen at a flow rate of about 9 sccm. To accommodate a hydrogen source gas. In another example, the WVG system includes hydrogen containing hydrogen gas at a flow rate of about 10 sccm and a flow rate of about 20 sccm to form an oxidizing gas containing oxygen at a rate of about 9.8 sccm and water vapor at a rate of about 10 sccm. Accept the source gas. In another example, nitros oxide as the oxygen source gas is used with the hydrogen source gas to form water vapor during the ALD process. Generally, 2 molar equivalents of nitros oxide are substituted for each molar equivalent of oxygen gas.

WVG systems contain catalysts such as catalyst-lined reactors or catalyst cartridges, in which case the oxidizing gas containing water vapor is generated by a catalytic chemical reaction between a source of hydrogen and a source of oxygen. WVG systems differ from pyrogenic generators, which typically produce water vapor as a result of ignition reactions at temperatures above 1000 ° C. WVG systems containing a catalyst generally produce water vapor at low temperatures in the range of about 100 ° C. to about 500 ° C., preferably at temperatures of about 350 ° C. or less. The catalyst contained in the catalytic reactor may include metals or alloys such as palladium, platinum, nickel, iron, chromium, ruthenium, rhodium, alloys thereof or combinations thereof. Ultra high purity water is ideal for the ALD process of the present invention. In one embodiment, the oxygen source gas is allowed to flow through the WVG system for about 5 seconds to prevent unreacted hydrogen from flowing downstream. The hydrogen source gas is then allowed to enter the reactor for about 5 seconds. The catalytic reaction between oxygen and a hydrogen source gas (eg H2, O2) generates water vapor. Regulating the flow of oxygen and hydrogen source gas allows precise control of the oxygen and hydrogen concentration in the formed oxidizing gas containing water vapor. Water vapor may contain residues of hydrogen source gas, oxygen source gas, or a combination thereof. Suitable WVG systems are commercially available, including steam generators (WVG) from Fujikin of America, Inc. in Santa Clara and / or Ultrasonic Catalytic Steam Generator Systems (CSGS) from Menlo Park, California.

2B illustrates one configuration of a WVG system 286. Hydrogen source 262, oxygen source 264 and carrier gas source 266 are connected to WVG system 286 by conduit system 261. Conduit system 261 contains conduits and valves, which allow gas from hydrogen source 262, oxygen source 264, and / or carrier gas source 266 to pass through gas input 267 and gas filter 268. It is possible to fluidly communicate with the catalytic reactor 270 independently. Water vapor is formed in and radiated from the catalytic reactor 270. In addition, conduit system 261 contains conduits and valves, which enable to independently bypass gas from hydrogen source 262, oxygen source 264 to catalytic reactor 270 at junction 271. . Thus additional hydrogen source gas and / or oxygen source gas may bypass the catalytic reactor 270 and may be combined with water vapor to form an oxygen or hydrogen rich oxidizing gas. Gas sensor 272 and gas filter 274 are connected to downstream conduit system 261 from catalytic reactor 270. Gas sensor 272 may be used to determine the composition of the oxidizing gas, including concentrations of oxygen, hydrogen, and water. The oxidizing gas may pass through the gas filter 274 before leaving the WVG system 286.

A pulse of purge gas, preferably argon or nitrogen, is generally introduced in steps 130 and 150 at a flow rate of about 2 standard liters per minute (sim) to about 22 sim, preferably about 10 sim. Each process cycle (steps 120-150) occurs for a time period in the range of about 0.01 seconds to about 20 seconds. In one example, the process cycle lasts about 10 seconds. In another example, the process cycle lasts about 2 seconds. Longer process steps lasting about 10 seconds deposit excellent hafnium-containing films but reduce throughput. Specific purge gas flow rates and durations of process cycles are obtained through experiments. In one example, a 300 mm diameter wafer requires about twice the flow rate or for the same duration as a 200 mm diameter wafer, thereby maintaining similar throughput.

In one embodiment, hydrogen gas is applied as a carrier gas, purge and / or reactant gas, thereby reducing halogen contaminants from the deposited material. Precursors containing halogen elements (eg HfCl 4, SiCl 4, and Si 2 Cl 6) readily contaminate the deposited dielectric material. Hydrogen will make a hydrogen halide (eg HCl) as a reductant, volatile and removable by-product. Thus, hydrogen may be used as a carrier gas or reaction gas when compounded with a precursor compound (eg hafnium, silicon, oxygen precursor) and may include other carrier gases (eg Ar or N 2). In one example, a water / hydrogen mixture is used to reduce the halogen concentration and increase the oxygen concentration of the deposited material at a temperature in the range of about 100 ° C to about 500 ° C. In one example, the water / hydrogen mixture can be obtained by injecting an excess of hydrogen source gas into the WVG system, thereby forming hydrogen-rich steam.

In another embodiment, FIG. 3 shows an exemplary process sequence 200 for forming a hafnium-containing material, such as hafnium silicate. The substrate is loaded into the process chamber, the process chamber can perform cyclic deposition and the process conditions are adjusted (step 205). The substrate may be exposed to a purification and optional presoak process prior to beginning the ALD cycle (step 207). The substrate is exposed to a pulse of hafnium precursor, which pulse is introduced into the process chamber for a time between about 0.1 seconds and about 5 seconds (step 210). The pulse of purge gas enters the process chamber (step 215), thereby removing or purging any residual hafnium precursor or by-products. Next, a pulse of oxidizing gas is introduced into the process chamber for a time ranging from about 0.1 seconds to about 10 seconds (step 220). The oxidizing gas can include a number of oxidizing elements such as oxygen and water vapor obtained from the WVG system. In addition, a pulse of purge gas is introduced into the process chamber (step 225), thereby removing or purging any residual oxidizing compounds or by-products. The substrate is then exposed to a pulse of silicon precursor, which pulse is introduced into the process chamber for a time ranging from about 0.1 seconds to about 10 seconds (step 230). In addition, a pulse of purge gas is pulsed into the process chamber (step 235), thereby removing or purging any residual silicon precursor or by-products. Next, another pulse of oxidizing gas is introduced into the process chamber for a time ranging from about 0.1 seconds to about 10 seconds (step 240). In addition, a pulse of purge gas is introduced into the process chamber (step 245), thereby removing or purging any residual oxidizing compounds or by-products. Suitable carrier gases or purge gases may include helium, argon, nitrogen, hydrogen, shaping gas, oxygen or combinations thereof.

Referring to step 250, after each deposition cycle (steps 210 to 245), a hafnium-containing material, such as hafnium silicate, having a first thickness is deposited over the substrate surface. In general, each deposition cycle forms a layer having a thickness in the range of about 0.5 kPa to about 10 kPa. Depending on the specific instrument requirements, subsequent deposition cycles may be required to deposit the hafnium-containing material at a predetermined thickness. The deposition cycles (steps 210 through 245) may be repeated until the desired or predetermined thickness of the hafnium-containing material is obtained, and if obtained in step 250, process sequence 200 ends at step 260.

Hafnium silicate material formed by the deposition process described herein has a chemical empirical formula HfSiO _x . Hafnium silicate may be a homogeneous mixture of hafnium oxide (HfO _x or HfO ₂ ) and silicon oxide (SiO _x or SiO ₂ ) or a single phase HfSiO ₄ material. Hafnium silicate may have a chemical molecular formula HfSiO _4, process conditions, hafnium silicate by the change of (e.g. time, temperature, precursors) are there the element concentration can be varied, for example, HfSiO _{3 .8 0} or _{HfSi. It} can be ₈ O _{3 .8} .

The ALD process shown in FIG. 3 generally occurs in the process chamber at a pressure in the range of about 1 Torr to about 100 Torr, preferably about 1 Torr to about 20 Torr, more preferably about 1 Torr to about 10 Torr. The temperature of the substrate is generally in the range of about 70 ° C to about 1000 ° C, preferably about 100 ° C to about 650 ° C, more preferably about 250 ° C to about 500 ° C. The optional presoak process in step 207 is after the ALD cycle begins, and includes exposing the substrate to an oxidizing gas containing water vapor generated from the WVG system, as described in step 115.

During step 210, the hafnium precursor is introduced into the process chamber at a flow rate in the range of about 5 sccm to about 200 sccm. Hafnium precursor is introduced with a carrier gas such as nitrogen and at a total flow rate ranging from about 50 sccm to about 1000 sccm. Hafnium precursor is pulsed into the process chamber at a rate in the range of about 0.1 seconds to about 10 seconds. In one embodiment, the hafnium precursor is pulsed at a rate in the range of about 1 second to about 5 seconds, for example about 3 seconds. In another embodiment, the hafnium precursor is pulsed at a rate in the range of about 0.1 seconds to about 1 second, for example about 0.5 seconds. In one example, the hafnium precursor is preferably hafnium tetrachloride, and in other instances the hafnium precursor is preferably TDEAH or other tatrakis (dialkylamino) hafnium compounds.

In one embodiment, as shown in FIG. 2A, the hafnium precursor is generally distributed into the process chamber 280 by introducing a carrier gas through an ampoule 282 containing the hafnium precursor. The temperature of the ampoule 282 is maintained at a temperature that depends on the hafnium precursor, such as in the range of about 20 ° C to about 300 ° C. In one example, ampoule 282 contains HfCl 4 at a temperature in the range of about 150 ° C to about 200 ° C. In another example, ampoule 282 containing a liquid precursor (eg, TDEAH, TDMAH, TDMAS, or Tris-DMAS) may be pressurized, thereby delivering the liquid precursor to injector valve system 281. In general, the ampoule 282 containing the liquid precursor may be pressured at a pressure in the range of about 138 kPa (about 20 psi) to about 414 kPa (about 60 psi), and may be about 100 ° C. or less, preferably about 20 ° C. to about 60 It may be heated to a temperature in the range of ° C. The injector valve system 281 combines the liquid precursor with the carrier gas, thereby forming precursor vapor, which is injected into the process chamber 280. The carrier gas may comprise nitrogen, argon, helium, hydrogen or mixtures thereof, and the carrier may be preheated to a temperature in the range of about 85 ° C to about 150 ° C.

In steps 220 and 240, the oxidizing gas containing water vapor is introduced into the process chamber 280 at a rate in the range of about 20 sccm to about 1000 sccm, preferably about 50 sccm to about 200 sccm. The oxidizing gas is pulsed into the process chamber 280 at a rate ranging from about 0.1 seconds to about 10 seconds depending on the desired composition of the deposited hafnium-containing material and the particular process conditions. In one embodiment, the oxidizing gas is pulsed at a rate of about 1 second to about 3 seconds, for example about 1.7 seconds. In another embodiment, the oxidizing gas is pulsed at a rate of about 0.1 seconds to about 1 second, for example about 0.5 seconds.

The oxidizing gas can be made from the WVG system 286, which is in fluid communication with the process chamber 280 by conduits 287. Hydrogen source gas H2 and oxygen source gas O2 flow independently into WVG system 286 at flow rates ranging from about 20 sccm to about 300 sccm, respectively. In general, the oxygen source gas has a higher flow rate than the hydrogen source gas. In one example the hydrogen source gas has a flow rate of about 100 sccm and the oxygen source gas has a flow rate of about 120 sccm, thereby enriching oxygen in the water vapor.

In another embodiment of the WVG system, the flow of hydrogen is greater than the flow of oxygen, for example the hydrogen source gas has a flow rate of about 250 sccm and the oxygen source gas has a flow rate of about 100 sccm. Thus, the water vapor flowing from the WVG system is rich in hydrogen. For example, when the hydrogen source gas has a flow rate of 250 sccm and the oxygen source gas has a flow rate of about 100 sccm, the outflow of the oxidizing gas has a partial flow rate of about 50 sccm of hydrogen and about 100 sccm of water vapor. Hydrogen-rich steam has a number of important functions. First, excess hydrogen in water vapor increases the removal rate of certain pollutants such as halogens. During the deposition process containing HfCl 4 or other halogenated precursors, excess hydrogen gas reacts with chlorine, thereby forming hydrogen chloride as a volatile that is easily removed by the purification step. Second, excess hydrogen in the water vapor prevents the oxidation of certain metal gate layers. In a MIM capacitor or instrument, the stack may contain a dielectric layer sandwiched between two metal layers, such as aluminum or tungsten. While forming a dielectric layer, such as a silicate compound, excess hydrogen reduces the metal layer and water vapor oxidizes the dielectric layer.

In step 230, the silicon precursor is introduced at a flow rate in the range of about 5 sccm to about 200 sccm, or at a flow rate in the range of about 1 mg / min to about 50 mg / min, preferably about 5 mg / min to about 25 mg / min. The silicon precursor is generally introduced with a carrier gas such as nitrogen at a total flow rate ranging from about 50 sccm to about 1000 sccm. The silicon precursor is pulsed into the process chamber at a rate ranging from about 0.1 seconds to about 10 seconds, depending on the particular process and the desired silicon concentration. In one embodiment, the silicon precursor is pulsed at a rate of about 1 second to about 5 seconds, for example about 3 seconds. In another embodiment, the silicon precursor is pulsed at a rate ranging from about 0.1 seconds to about 1 second, for example about 0.5 seconds. In one example, the silicon precursor is preferably tris (dimethylamino) silane ((Me ₂ N) ₃ SiH or Tris-DMAS), tetrakis (dimitelamino) silane ((Me ₂ N) ₄ Si or TDMAS) or other di Alkylaminosilane, and in another embodiment the silicon precursor is preferably silane (SiH ₄ ).

During steps 215, 225, 235, 245, pulses of purge gas, such as argon or nitrogen, are generally introduced in the range of about 2 sim to about 22 sim, preferably at a flow rate of about 10 sim. Each process cycle (steps 210-245) may occur for a time period in the range of about 2 seconds to about 40 seconds. In one example the time period of the process cycle lasts about 20 seconds, and in another embodiment the time period of the process cycle lasts about 4 seconds. Longer process steps lasting about 20 seconds deposit a hafnium-containing film but exhibit reduced throughput.

In other embodiments, hafnium-containing materials, such as hafnium silicates, may be formed by omitting any of the steps of introducing an oxidizing gas and subsequent purge steps. In one example, steps 220 and 225 are omitted and thus the hafnium silicate material may be formed by sequentially pulsing the hafnium precursor, purge gas, silicon precursor, purge gas, oxidizing gas and purge gas. In other embodiments, steps 240 and 245 are omitted, so hafnium silicate material may be formed by sequentially pulsing hafnium precursor, purge gas, oxidizing gas, purge gas, silicon precursor, purge gas.

4 shows an exemplary process sequence 300 for forming a hafnium-containing material, such as hafnium silicate, in accordance with another embodiment of the present invention. The substrate is loaded into a process chamber capable of performing cyclical deposition, and process conditions are adjusted (step 310). The substrate may be exposed to an optional presoak process and purge prior to beginning the ALD cycle (step 315). The substrate is exposed to a pulse of hafnium precursor and a pulse of silicon precursor, which completely or at least partially overlap in time and enter the process chamber for a time period in the range of about 0.1 seconds to about 5 seconds (step 320). The pulse of purge gas is pulsed into the process chamber (step 330), thereby removing or purging any remaining hafnium precursor, silicon precursor or by-products. Next, a pulse of oxidizing gas is introduced into the process chamber (step 340). The oxidizing gas may include a number of coral gases such as water vapor and oxygen obtained from the WVG system. In addition, a pulse of purge gas is introduced into the process chamber (step 350), thereby removing or purging any remaining reducing compound. Suitable carrier gases or purge gases may include helium, argon, nitrogen, hydrogen, shaping gas, oxygen, or mixtures thereof.

Referring to step 360, after each deposition cycle (steps 320-350), hafnium-containing material, such as hafnium silicate, having a first thickness will be deposited over the substrate surface. During the ALD process, each deposition cycle forms a layer having a thickness in the range of about 0.5 kPa to about 10 kPa. Depending on the particular instrument requirements, subsequent deposition cycles may be required to deposit hafnium-containing materials having a predetermined thickness. The deposition cycles (steps 320-350) may be repeated until a desired or predetermined thickness for the hafnium-containing material is obtained, and if obtained in step 360, process sequence 300 stops at step 370.

The ALD process shown in FIG. 4 generally occurs in the process chamber at a pressure of about 1 Torr to about 100 Torr, preferably about 1 Torr to about 20 Torr, more preferably about 1 Torr to about 10 Torr. The temperature of the substrate is in the range of about 70 ° C to about 1000 ° C, preferably about 100 ° C to about 650 ° C, more preferably about 250 ° C to about 500 ° C. The optional presoak process in step 315 may occur after the start of the ALD cycle and may include exposing the substrate to oxidizing gas containing water vapor generated from the WVG system, as described in step 115. have.

During step 320, the hafnium precursor and the silicon precursor are each introduced by flowing into the process chamber as a pulse of precursor, ie the pulsed precursor is the introduction of this precursor into the process chamber. 5A-5E, t ₁ corresponds to a time period, hafnium precursor and silicon precursor are pulsed during step 320, and t ₂ corresponds to the time period during steps 330, 340, 350. The periods of time t ₁ , t ₂ are not graphed with respect to each other. In the embodiment shown in FIG. 5A, the hafnium precursor and the silicon precursor are pulsed independently for the same time period and all precursors flow for the entire t ₁ . For example, the hafnium precursor and the silicon precursor are pulsed simultaneously for about 2 seconds.

In another embodiment shown by FIGS. 5B-5C, the hafnium precursor and the silicon precursor are pulsed independently, the first precursor flows for the entire t ₁ and the second precursor flows for the intermediate t ₁ . For example, when t1 in FIG. 5B lasts about 2 seconds, the hafnium precursor is pulsed for about 2 seconds and the silicon precursor is pulsed for about 1.5 seconds during the middle of the pulsed hafnium precursor. Alternatively, when t1 in FIG. 5C lasts about 2 seconds, the silicon precursor is pulsed for about 2 seconds and the hafnium precursor is pulsed for about 1.5 seconds during the middle of the pulsed silicon precursor.

In another embodiment shown by FIGS. 5D-5E, the hafnium precursor and the silicon precursor are pulsed independently, partially overlapping, the first precursor flows at the beginning of t1 and does not flow to the end of t1, and the second precursor It does not flow at the beginning of t1 but flows to the end of t1. For example, in FIG. 5D when t1 lasts about 2 seconds, the hafnium precursor is pulsed for about 1.5 seconds at the beginning of t1 and the silicon precursor is pulsed for about 1.5 seconds at the end of t1. In another example, when t1 in FIG. 5E lasts about 2 seconds, the silicon precursor is pulsed for about 1.75 seconds at the beginning of t1 and the hafnium precursor is pulsed for about 1.5 seconds at the end of t1.

Alternatively, the first precursor (eg hafnium precursor) may be pulsed during any part of the time period of t1 and the second precursor (eg silicon precursor) that overlaps or does not overlap any part of the time period of t1. Can be pulsed during. Thus, hafnium precursors, silicon precursors, or other precursors may be independently pulsed into the process chamber without overlapping time or with partial overlap of time. In one example when t1 lasts about 2 seconds, the hafnium precursor is pulsed for about 2 seconds and the silicon precursor is pulsed for about 0.5 seconds during the pulse of the hafnium precursor. In another example when t1 lasts about 2 seconds, the hafnium precursor is pulsed for about 0.5 seconds and the silicon precursor is pulsed for about 0.5 seconds without overlap or with a pulse of hafnium precursor. In another example when t1 lasts about 2 seconds, the hafnium precursor is pulsed for about 0.5 seconds and the silicon precursor is pulsed for about 0.5 seconds during or with overlap of the hafnium precursor. Also, the plurality of pulses, the first precursor and the second precursor may be pulsed for a time period of t1.

During step 320, the hafnium precursor is introduced into the process chamber at a flow rate in the range of about 5 sccm to about 200 sccm. Hafnium precursors are generally introduced with a carrier gas such as nitrogen at a total flow rate ranging from about 50 sccm to about 1000 sccm. Hafnium precursor may be pulsed into the process chamber at a rate ranging from about 0.1 seconds to about 10 seconds. In one embodiment, the hafnium precursor is pulsed at a rate ranging from about 1 second to about 5 seconds, for example about 3 seconds. In another embodiment, the hafnium precursor is pulsed at a rate ranging from about 0.1 seconds to about 1 second, for example about 0.5 seconds. In one example, the hafnium precursor is preferably hafnium tetrachloride, and in other embodiments the hafnium precursor is preferably TDEAH.

Hafnium precursor is generally dispensed into process chamber 280 by introducing a carrier gas through ampoule 282 containing hafnium precursor, as shown in FIG. 2A. The carrier gas and the hafnium precursor form precursor vapor, which flows through the conduit 283 into the process chamber 280. The temperature of the ampoule 282 is maintained at a temperature that depends on the hafnium precursor, such as in the range of about 20 ° C to about 300 ° C. In one example ampoule 282 contains HfCl 4 at a temperature in the range of about 150 ° C to about 200 ° C. In another example, ampoule 282 containing a liquid precursor (eg, TDEAH, TDMAH, TDMAS, or Tris-DMAS) may be under pressure, thereby delivering the liquid precursor to injector valve system 281. In general, the ampoule 282 containing the liquid precursor may be pressured at a pressure in the range of about 138 kPa (about 20 psi) to about 414 kPa (about 60 psi), and may be about 100 ° C. or less, preferably about 20 ° C. to about 60 It may be heated to a temperature in the range of ° C. The injector valve system 281 combines the liquid precursor with the carrier gas, thereby forming precursor vapor injected into the process chamber 280. The carrier gas may comprise nitrogen, argon, helium, hydrogen or a combination thereof and the carrier may be pre-heated to a temperature in the range of about 85 ° C to about 150 ° C.

During step 320, the silicon precursor is at a flow rate in the range of about 5 sccm to about 200 sccm or at a flow rate in the range of about 1 mg / min to about 50 mg / min, preferably in a range of about 5 mg / min to about 25 mg / min. Is introduced into the process chamber. The silicon precursor is generally introduced with a carrier gas, such as nitrogen, with a total flow rate ranging from about 50 sccm to about 1000 sccm. The silicon precursor is pulsed into the process chamber at a rate in the range of about 0.1 seconds to about 10 seconds. In one embodiment, the silicon precursor is pulsed at a rate ranging from about 1 second to about 5 seconds, for example about 3 seconds. In another embodiment, the silicon precursor is pulsed at a rate ranging from about 0.1 seconds to about 1 second, for example about 0.5 seconds. In one example, the silicon precursor is preferably Tris-DMAS or TDMAS, and in other embodiments the silicon precursor is preferably silane.

In an alternative embodiment during step 320, the hafnium precursor and the silicon precursor may be combined prior to being pulsed into the process chamber. The hafnium / silicon precursor mixture is formed by compounding the proportional amounts of silicon precursor and hafnium precursor, thereby obtaining the desired Hf: Si ratio in the deposited hafnium-containing material. Process gas containing a hafnium / silicon precursor mixture may be formed by flowing a carrier gas through the precursor mixture in an ampoule. The hafnium / silicon precursor mixture is sequentially pulsed with the oxidizing gas by an ALD process, thereby forming a hafnium-containing material such as hafnium silicate material. Hafnium silicates deposited by the process described herein have a chemical formula HfSi _y O _x where y can be adjusted by changing the molar ratio of silicon precursor and hafnium precursor in the hafnium / silicon precursor mixture. For example, if the ratio of hafnium precursor to silicon precursor is greater than one, y is less than one. Y is greater than 1 if the ratio of hafnium precursor to silicon precursor is less than one.

During step 340, the oxidizing gas is introduced into the process chamber 280 at a flow rate in the range of about 20 sccm to about 1000 sccm, preferably about 50 sccm to about 200 sccm. The oxidizing gas is pulsed into the process chamber 280 at a rate in the range of about 0.1 seconds to about 10 seconds. In one embodiment, the oxidizing gas is pulsed at a rate ranging from about 1 second to about 3 seconds, for example about 1.7 seconds. In another embodiment, the oxidizing gas is pulsed at a rate in the range of about 0.1 seconds to about 1 second, for example about 0.5 seconds.

In one embodiment of process sequence 300, oxidizing gas is produced from WVG system 286, which is in fluid communication with process chamber 280 by conduit 287. Each of the hydrogen source gas and the oxygen source gas flows into the WVG system 286 at a flow rate in the range of about 20 sccm to about 200 sccm. In general, the flow rate of the oxygen source gas is higher than that of the hydrogen source gas, for example, the hydrogen source gas has a flow rate of about 100 sccm and the oxygen source gas has a flow rate of about 120 sccm. Thus, water vapor flowing through the WVG system 286 is rich in oxygen. For example, when the hydrogen source gas has a flow rate of about 100 sccm and the oxygen source gas has a flow rate of about 120 sccm, the outflow of the oxidizing gas includes a partial flow rate of oxygen of about 70 sccm and water vapor of about 100 sccm. In another example, the hydrogen source gas has a flow rate of about 250 sccm and the oxygen source gas has a flow rate of about 100 sccm. Thus, the water vapor flowing from the WVG system is rich in hydrogen.

During steps 330 and 350, pulses of purge gas, such as argon or nitrogen, are generally introduced at flow rates ranging from about 2 sim to about 22 sim, preferably about 10 sim. Each process cycle (steps 320-350) may occur for a time period in the range of about 0.5 seconds to about 20 seconds. In one example, the process cycle lasts about 10 seconds. In another embodiment, the process cycle lasts about 2 seconds.

In embodiments involving process sequences 100, 200, 300, alternative oxidizing gases, such as traditional oxidizing agents, may be used in place of oxidizing gases containing water vapor formed from WVG systems. Alternative oxidizing gases are hydraulically introduced into the process chamber from an oxygen source containing water not made from the WVG system, which includes oxygen (O 2), ozone (O 3), atom-oxygen (O), hydrogen peroxide (H 2 O 2), Nitros oxide (N 2 O), nitrile oxide (NO), dinitrogen pentoxide (N 2 O 5), nitrogen dioxide (NO 2), derivatives thereof or combinations thereof. Embodiments of the present invention provide a process that benefits from oxidizing gases containing water vapor formed from WVG systems, while other embodiments provide traditional oxidants or alternatives while forming hafnium-containing materials and other dielectric materials during the deposition process described herein. It provides a process using a conventional oxidizing gas.

Many precursors are within the scope of embodiments of the present invention for depositing dielectric materials described herein. One important precursor feature is to have a good vapor pressure. At ambient temperature and pressure the precursor may be a gas, a liquid or a solid. The volatilized precursor is used in an ALD chamber. The organometallic compound contains at least one metal atom and at least one organo-containing functional group, such as an amide, alkyl, alkoxyl, alkylamino, or anilide. The precursor may comprise an organometallic, inorganic or halide compound.

Exemplary hafnium precursors include halides, alkylamino, cyclopentadienyl, alkyl, alkoxides, derivatives thereof or combinations thereof. Hafnium halide compounds useful as hafnium precursors may include HfCl ₄ , HfI ₄ and HfBr ₄ . Hafnium alkylamino compounds useful as hafnium precursors include (RR'N) ₄ Hf, where R or R 'are independently hydrogen, methyl, ethyl, propyl, butyl. Hafnium precursors useful for depositing hafnium-containing materials include (Et ₄ N) ₄ Hf, (Me ₂ N) ₄ Hf, (MeEtN) ₄ Hf, ( ^t BuC ₅ H ₄ ) ₂ HfCl ₂ , (C ₅ H ₅ ) ₂ HfCl ₂ , (EtC ₅ H ₄ ) ₂ HfCl ₂ , (Me ₂ C ₅ ) ₂ HfCl ₂ , (Me ₂ C ₅ ) HfCl ₃ , ( ⁱ PrC ₅ H ₄ ) HfCl ₂ , ( ⁱ PrC ₅ H ₄ ) HfCl ₃ , ( ^t BuC ₅ H ₄ ) ₂ HfMe ₂ , (acac) ₄ Hf, (hfac) ₄ Hf, (tfac) ₄ Hf, (thd) ₄ Hf, (NO ₃ ) ₄ Hf, ( ^t BuO) ₄ Hf, ( ⁱ PrO) ₄ Hf, (EtO) ₄ Hf, (MeO) ₄ Hf or derivatives thereof. Preferably the hafnium precursor used during the deposition process includes HfCl ₄ , (Et ₂ N) ₄ Hf, or (Me ₂ N) ₄ Hf.

Exemplary silicon precursors used to deposit silicon containing materials include silanes, alkylaminosilanes, silanols, alkoxy silanes, for example silicon precursors include (Me2N) 4Si, (Me2N) 3SiH, (Me2N) 2SiH2, (Me2N) SiH3, (Et2N) 4Si, (Et2N) 3SiH, (MeEtN) 4Si, (MeEtN) 3SiH, Si (NCO) 4, MeSi (NCO) 3, SiH4, Si2H6, SiCl4, Si2Cl6, MeSiCl3, HSiCl3, Me2SiCl2 , H 2 SiCl 2, MeSi (OH) 3, Me 2 Si (OH) 2, (MeO) 4 Si, (EtO) 4 Si or derivatives thereof. Other alkylaminosilane compounds used as silicon precursors include (RR'N) _{4- n} SiH _n , where R or R 'are independently hydrogen, methyl, ethyl, propyl or butyl and n = 0-3. Other alkoxy silanes may be described by the generic chemical formula (RO) 4-nSiLn, where R = methyl, ethyl, propyl or butyl, L = H, OH, F, Cl, Br or I and Mixtures thereof. Higher silanes are also used as silicon precursors within embodiments of the present invention. High silanes are disclosed in US patent application Ser. No. 10 / 688,797, issued as US 20040224089 and filed Oct. 17, 2003 entitled “Silicone-Containing Layer Deposition with Silicon Compounds”, in its entirety to describe a silicon precursor. Is hereby incorporated by reference. Preferably, the silicon precursor used during the deposition process includes (Me 2 N) 3 SiH, (Et 2 N) 3 SiH, (Me 2 N) 4 Si, (Et 2 N) 4 Si or SiH 4.

In one embodiment, nitrogen can be added to other dielectric materials and hafnium-containing materials deposited during the processes described herein. In one example, the hafnium oxide material can be nitrided to form a hafnium oxynitride material, and the hafnium silicate material can be nitrided to form a hafnium silicon oxynitride material. In one example, the hafnium silicate film is deposited rich in silicon, with little or no nitrogen near the substrate / dielectric interface. As the film thickness increases, more hafnium mixes into the film thereby increasing the dielectric constant. Nitrogen can also be added to the bulk of the film, thereby reducing the diffusion of impurities through the film. Alternatively nitrogen can be added near the top of the film, thereby providing a stable capping layer.

In addition, nitrogen may be added to hafnium-containing materials and other dielectric materials by nitrogen bombardment, which may consist of such as nitrogen plasma, annealing the substrate in a nitrogen containing environment and / or in an ALD process. An additional half contains a nitrogen precursor into the reaction. The nitrogen plasma process includes exposing the substrate surface to a plasma nitridation process after half the reaction upon completion of the deposition of the hafnium-containing material and / or upon completion of the ALD cycle. For example, a nitrification remote-plasma is exposed to a hafnium oxide film thereby forming a hafnium oxynitride film or to a hafnium silicate film to form a hafnium silicon oxynitride film.

In another embodiment, the hafnium-containing material deposited over the substrate is annealed in a nitrogen containing atmosphere such as N 2, NH 3, N 2 H 4, NO, N 2 O, atom-N, or a combination thereof. The substrate is heated to a temperature in the range of about 800 ° C. to about 1100 ° C. for a time period in the range of about 15 seconds to about 10 minutes. For example, a substrate containing a hafnium silicate film is thermally annealed at 900 ° C. for about 1 minute in a chamber filled with NH 3, thereby forming a hafnium silicon oxynitride film.

In another embodiment, the hafnium silicon oxynitride material may be formed during an ALD process by providing a cycle containing hafnium precursor reaction, silicon precursor reaction, nitrogen precursor reaction, and at least one oxidizing gas reaction. Nitrogen precursor reactions can be added into the ALD process during cycles at a constant rate relative to hafnium, silicon, and oxygen precursor reactions. In one example, the nitrogen precursor reaction is added in both ALD processes about every time of hafnium, silicon and oxygen precursor reaction. In addition, the cycle rate can vary, thereby controlling the rate of nitrogen incorporated within the film thickness. In one embodiment, the ALD process can form a hafnium silicon oxynitride grade film having a higher proportion of nitrogen near the top of the film than at the lower portion of the film. Generally the top of the film containing the high nitrogen concentration is about 20% or less, preferably 10% or less, more preferably 5% or less of the top of the film. If the silicon precursor reaction is omitted, hafnium oxynitride films can be formed by similar ALD processes. Preferably, the oxidizing gas contains water vapor formed from the WVG system.

Exemplary nitrogen precursors may include: NH 3, N 2, hydrazine (eg N 2 H 4, MeN 2 H 3), amines (eg Me 3 N, Me 2 NH, MeNH 2), aniline (eg C 6 H 5 NH 2), organic azide ( For example MeN3 or Me3SiN3), inorganic azides (eg NaN3, Cp2CoN3), radical nitrogen compounds (eg N3, N2, N, NH, NH2), derivatives thereof or combinations thereof. Radical nitrogen compounds can be made by heat, hot-wire or plasma.

In alternative embodiments, various metal oxides and metal silicates may be formed by sequentially pulsing the metal precursor with an oxidizing gas containing water vapor produced from a WVG system. The ALD process disclosed herein (eg process sequences 100, 200, 300) can be altered by substituting hafnium and / or silicon precursors with other metal precursors, whereby hafnium aluminate, titanium silicate, zirconium oxide, zirconium Additional dielectrics such as silicates, zirconium aluminates, tantalum oxides, tantalum silicates, titanium oxides, titanium silicates, silicon oxides, aluminum oxides, aluminum silicates, lanthanum oxides, lanthanum silicates, lanthanum aluminates, nitrites, derivatives thereof or combinations thereof. Form a substance. In one embodiment, two or more ALD processes are operated simultaneously to deposit one layer on top of another. For example, the combined process includes a first ALD process for forming a first dielectric material and a second ALD process for forming a second dielectric material. Combined processes can be used to make a variety of hafnium-containing materials such as, for example, hafnium aluminum silicates or hafnium aluminum silicon oxynitrides. In one example, the dielectric stack material is formed by depositing a first hafnium-containing material on a substrate and then depositing a second hafnium-containing material thereon. The composition of the first and second hafnium-containing materials may vary in composition, one layer may include hafnium oxide and the other layer may include hafnium silicate. In one aspect, the bottom layer comprises silicon. Alternative metal precursors used during the ALD process described herein include ZrCl 4, Cp 2 Zr, (Me 2 N) 4 Zr, (Et 2 N) 4 Zr, TaF 5, TaCl 5, (tBuO) 5 Ta, (Me 2 N) 5 Ta, (Et 2 N) 5 Ta, (Me 2 N) 3 Ta (NtBu), (Et2N) 3Ta (NtBu), TiCl4, TiI4, (iPrO) 4Ti, (Me2N) 4Ti, (Et2N) 4Ti, AlCl3, Me3Al, Me2AlH, (AMD) 3La, ((Me3Si) (tBu) N ) 3La, ((Me3Si) 2N) 3La, (tBu2N) 3La, (iPr2N) 3LA, derivatives thereof, or combinations thereof.

Many industrial applications exist for product dielectric materials formed during the deposition process described by various embodiments. Within the microelectronics industry, product materials include high-kV transistor gate dielectric materials, transistor gate interfacial engineering, high-kPa capacitor dielectric materials (DRAMs), seed layers, diffusion barrier layers, adhesive layers, insulating layers, and patterned surfaces ( For example as a functional surface group for selective deposition). In the area of microelectromechanical systems (MEMS), the materials formed during the processes described herein can be used as insulating or structural films.

hardware

6 shows a schematic cross-sectional view of a process chamber 610 that can be used to perform integrated circuit fabrication in accordance with an embodiment described herein. Process chamber 610 generally receives substrate support pedestal 648 which is used to support the substrate (not shown). The substrate support pedestal 648 is movable in the vertical direction into the process chamber 610 using the displacement mechanism 648A.

Depending on the particular process, the substrate may be heated to the desired temperature during or prior to deposition. For example, substrate support pedestal 648 may be heated by embedding heating element 652A. The substrate support pedestal 648 can be resistively heated by applying current from the AC power source 652 to the heating element 652A. The substrate (not shown) is in turn heated by the support pedestal 648. Alternatively, the substrate support pedestal 648 can be heated using a radiant heater, such as a lamp (not shown).

A temperature sensor 650A, such as a thermocouple, is also embedded in the substrate support pedestal 648, thereby monitoring the temperature of the pedestal 648 in a conventional manner. The measured temperature is used in the feedback loop, thereby controlling the AC power source 652 for the heating element 652A, and the substrate temperature can be controlled or maintained at the desired temperature appropriate for the particular process application.

Vacuum pump 618 is used to empty the process chamber 610 and to maintain pressure within the process chamber 610. The gas manifold 634 into which the process gas flows into the process chamber 610 is positioned above the substrate support pedestal 648. Gas manifold 634 is connected to a gas panel (not shown), which supplies and controls various process gases to process chamber 610.

Proper control and regulation of gas flow to gas manifold 634 is performed by mass flow controllers (not shown) and microprocessor controllers 670. The gas manifold 634 allows the process gas introduced in the process chamber 610 to be uniformly distributed and introduced. In addition, the gas manifold 634 may be selectively heated, thereby preventing densification of the reactive gas in the manifold.

Gas manifold 634 includes a plurality of electronic control valves (not shown). As used herein, the electronically controlled valve can provide a precise and precise gas flow to the process chamber 610 with open and closed cycles of the valve at a rate ranging from about 0.01 seconds to about 10 seconds, preferably from about 0.1 seconds to about 5 seconds. A control valve, for example, a long cycle may last about 3 seconds, and a short cycle may last about 0.5 seconds.

Microprocessor controller 670 may be a form of general purpose computer processor (CPU), which is industrially set up and used to control various chambers and subprocessors. The computer may use suitable memory, such as partial or remote, as random access memory, read only memory, floppy disk drive, compact disk drive, hard disk, or other form of digital storage device. Various support circuits may be coupled to the CPU to support the processor in a conventional manner. As desired, software routines may be performed by remote sources (eg, computers or servers) or stored in memory.

Software routines are performed to initiate process processing or sequences. When performed, the software routine converts the general purpose computer into a specific process computer, which controls the chamber operation, whereby the chamber process is performed. For example, software routines can be used to precisely control the activity of the electronic control valve for the performance of the process sequence according to the present invention. Alternatively, software routines may be performed in hardware, such as application specific integrated circuits or other forms of hardware execution or software or a combination of hardware.

FIG. 7 is a schematic cross-sectional view of one embodiment of a process chamber 680 that includes a gas delivery device 730 used for cyclic deposition, such as atomic layer deposition or rapid chemical vapor deposition. A detailed description of the process chamber 680 is described in US patent application Ser. No. 10 / 032,284, filed Dec. 21, 2001, published as US 20030079686 and entitled "Gas Delivery Apparatus and Methods for Atomic Layer Deposition". And US patent application Ser. No. 10 / 271,079, issued as US 20030121608 and filed Oct. 25, 2002, entitled “Gas Delivery Devices for Atomic Layer Deposition,” all of which are hereby incorporated by reference. As used herein, the terms sequential vapor deposition, rapid chemical vapor deposition, and atomic layer deposition (ALD) are used to refer to the sequential influx of precursors or reactants that deposit thin layers across the substrate structure. Sequential influx of reactants may be repeated, thereby depositing a plurality of thin layers, forming a uniform layer to the desired thickness. In one embodiment, a mixture of reactants containing one or more precursors (eg, hafnium precursors and silicon precursors) may be pulsed sequentially with other precursors (eg, water vapor). In addition, process chamber 680 may be employed for other deposition techniques.

Process chamber 680 includes a chamber body 682 having a sidewall 684 and a bottom 686. In the process chamber 680, the slit valve 688 provides access to a robot (not shown), whereby a substrate 690, such as a semiconductor substrate or glass substrate, having a diameter of 200 mm to 300 mm from the process chamber 680. Pass and get back.

The substrate support 692 supports the substrate 690 over the substrate receiving surface 691 in the process chamber 680. The substrate support 692 is mounted to lift the motor 714, thereby raising or lowering the substrate support 692 and the substrate 690 disposed thereon. A lift plate 716 connected to the lift motor 718 raises or lowers the pin 720 mounted in the process chamber 680 and movably disposed through the substrate support 692. The pin 720 raises or lowers the substrate 690 across the surface of the substrate support 692. Substrate support 692 may include a clamp ring or an electrostatic chuck, a pore chuck to secure the substrate 690 to the substrate support 692 during processing.

The substrate support 692 may be heated to increase the temperature of the substrate 690 disposed thereon. For example, the substrate support 692 may be heated using embedded heating elements, such as resistive heaters, or may be heated using radiant heat, such as a heating lamp disposed over the substrate support 692. Purification ring 722 may be disposed above substrate support 692, thereby defining purge channel 724, which provides purge gas to the periphery of substrate 690, thereby preventing deposition thereon.

Gas delivery device 730 is disposed on top of chamber body 682, thereby providing gas such as process gas and / or purge gas to process chamber 680. Vacuum system 778 communicates with purge channel 779 to thereby empty the desired gas from process chamber 680 and maintain a desired pressure range or desired pressure within pumping zone 766 of process chamber 680. Help

In one embodiment, the process gas and / or purge gas enter the process chamber 680 perpendicular to the plane of the substrate 690 (ie, 90 °) through the gas delivery device 730. Thus, the surface of the substrate 690 is symmetrically exposed to gas, thereby enabling uniform film formation on the substrate. The process gas may include hafnium-containing compounds (eg TDEAH, HfCl 4) for one pulse and oxidizing gases (eg water vapor generated from a WVG system) in another pulse.

The process chamber 680 shown in FIG. 7 may produce a more uniform film than in the chamber 610 shown in FIG. 6. In addition, the process chamber 680 employs a smaller cycle time than the process chamber 610, and the process chamber 680 is generally less time saturating and purifying the substrate with the precursor than the process chamber 610. It takes less time. Thus, process chambers 610 and 680 may contain hafnium-containing compounds for about 20 seconds or less, preferably process chamber 680 is about 10 seconds or less, more preferably about 5 seconds or It may contain hafnium-containing compounds for less than about 3 seconds or about 0.5 seconds.

In one embodiment, the gas delivery device 730 includes a chamber lid 732. The chamber lid 732 includes an expansion channel 734 extending from the center portion of the chamber lid 732 and a bottom surface 760 extending from the expansion channel 734 relative to the periphery of the chamber lid 732. Bottom surface 760 has a shape and size that substantially covers substrate 690 disposed over substrate support 692. Chamber lid 732 may have a choke 762 at the periphery of chamber lid 732 adjacent to the periphery of substrate 690. Cap portion 772 includes gas inlets 736A and 736B and a portion of expansion channel 734. Expansion channel 734 has gas inlets 736A and 736B, which provide gas flow from two similar valves 742A and 742B. The gas may be provided separately from and / or together with the valves 742A, 742B.

In one embodiment, chamber lid 732 is made from a metallic material such as stainless steel (eg, an iron-chromium alloy optionally containing nickel), aluminum, derivatives thereof, alloys thereof, or a combination thereof. In alternative embodiments, the chamber lid 732 includes a thermally insulating material, which material is a fused quartz, sapphire, pyrrolitic boron nitride (PBN) material, ceramic, derivatives thereof, or a combination thereof. In one example, a thermally insulating liner is added to the chamber lid 732, which covers almost a portion of the expansion channel 734 and the bottom surface 760 (not shown). Preferably, expansion channel 734 and bottom surface 760 may be machined into chamber lid 732 made of a thermally insulating material. Additional liners made of the same or similar thermally insulating materials may be added into the process chamber 680. In one example, slit valve 688 contains liner 687, sidewall 684 contains liner 683, and bottom surface 685 contains liner 689.

In one configuration, valves 742A, 742B are coupled to separate reactant gas sources and preferably coupled to the same purge gas source. For example, valve 742A is coupled to reactant gas source 738, valve 742B is coupled to reactant gas source 739, and all valves 742A and 742B are coupled to purge gas source 740. . Valves 742A, 742B include delivery lines 743A, 743B having valve seat assemblies 744A, 744B in fluid communication with valves 752A, 752B, respectively. Delivery lines 743A and 743B are in fluid communication with reactant gas sources 738 and 739 and in fluid communication with gas inlets 736A and 736B of expansion channel 734. Additional reactant gas sources, delivery lines, gas inlets and valves may be added to the gas delivery device 730 in alternative embodiments (not shown). The valve seat assemblies 744A, 744B of the delivery lines 743A, 743B control the flow of reactant gas from the reactant gas sources 738, 739 to the expansion channel 734. Purification gas 745A, 745B is in fluid communication with purge gas source 740 and intersects with delivery lines 743A, 743B downstream of valve seat assemblies 744A, 744B of delivery lines 743A, 743B. Valve seat assemblies 746A, 746B of purge lines 745A, 745B control the flow of purge gas from purge gas source 740 to delivery lines 743A, 743B. If a carrier gas is used to deliver the reactant gas from the reactant gas sources 738, 739, the same gas may be used as the carrier gas and purge gas (eg, nitrogen used as the carrier gas and nitrogen gas).

Each valve seat assembly 744A, 744B, 746A, 746B may comprise a diaphragm and a valve seat. The diaphragms can be biased open or closed and can be driven closed or open individually. The diaphragm may be pneumatically driven or electrically driven. Examples of pneumatically driven valves include pneumatically driven valves available from Fujikin and Veriflow. Examples of electrically driven valves include electrically driven valves available from Fujikin. Programmable logic controllers 748A, 748B may be coupled to valves 742A, 742B, thereby controlling the driving of the diaphragms of valve seat assemblies 744A, 744B, 746A, 746B of valves 742A, 742B. . The pneumatically actuated valve can provide a pulse of gas at a time period as low as about 0.020 seconds. The electrically driven valve can provide a pulse of gas in a time period as low as about 0.005 seconds. In general, pneumatically and electrically driven valves can provide pulses of gas with a high time period of about 3 seconds. While high time periods are possible for gas pulsing, typical ALD processes utilize ALD valves, thereby opening at intervals of about 5 seconds or less, preferably about 3 seconds or less, more preferably about 2 seconds or less. Generate a pulse of gas. In one embodiment, the ALD valve provides a pulse at intervals ranging from about 0.005 seconds to about 3 seconds, preferably from about 0.02 seconds to 2 seconds, more preferably from about 0.05 seconds to about 1 second. Electrically driven valves require the use of a driver coupled between the valve and the programmable logic controller.

Each valve 742A, 742B is a zero dead volume valve to enable flushing of reactant gas from delivery lines 743A, 743B when the valve seat assemblies 744A, 744B of the valve are closed. valve). For example, purge lines 745A, 745B may be located adjacent to valve seat assemblies 744A, 744B of delivery lines 743A, 743B. When valve seat assemblies 744A and 744B are closed, purge lines 745A and 745B provide purge gas to blow off delivery lines 743A and 743B. In one embodiment, the warmed purge gas (eg, about 50 ° C. to about 200 ° C.) is passed to heat the valve set assemblies 744A, 744B, thereby thereby not only in and above the delivery lines 743A, 743B. Prevents or reduces the densification of precursors. In the illustrated embodiment, the purge lines 745A, 745B are in a position slightly away from the valve seat assemblies 744A, 744B of the delivery lines 743A, 743B, whereby the purge gas is gapped when the valve seat assembly ( No direct transmission into 744A, 744B). As used herein, the zero dead volume valve is defined as a valve with negligible dead volume (ie, zero dead volume is not required).

Each valve 742A, 742B may be adapted to provide separate gas flows and / or combined gas flows of reactant gases 738, 739 and purge gas 740. Referring to valve 742A, one example of a combined gas flow of purge gas 740 and reactant gas 738 provided by valve 742A is from reactant gas source 738 via delivery line 743A. Pulses of reactant gas and a continuous flow of purge gas from purge gas source 740 through purge line 745A. Continuous flow of purge gas may be provided by opening the diaphragm of valve seat assembly 746A of purge line 745A. The pulse of reactant gas from the reactant gas source 738 may be provided by opening and closing the diaphragm of the valve seat 744A of the delivery line 743A. Referring to valve 742A, an example of separate gas flows of purge gas 740 and reactant gas 738 provided by valve 742A is a reactant from reactant gas source 738 through delivery line 743A. Pulses of gas and pulses of purge gas from purge gas source 740 through purge line 745A. The pulse of purge gas may be provided by opening and closing the diaphragm of the valve seat assembly 746A of the purge line 745A. The pulse of reactant gas from the reactant gas source 738 may be provided by opening and closing the diaphragm valve seat 744A of the delivery line 743A.

Delivery lines 743A, 743B of valves 742A, 742B may be connected to gas inlets 736A, 736B through gas conduits 750A, 750B. Gas conduits 750A, 750B may be integrated or may be separated from valves 742A, 742B. In one aspect, valves 742A, 742B are coupled in close proximity to expansion channel 734, whereby gas conduits 750A, 750B and delivery between valves 742A, 742B and gas inlets 736A, 736B. Reduce unnecessary volume of lines 743A and 743B.

In FIG. 7, expansion channel 734 includes a channel having an inner diameter, which diameter increases from top to bottom of expansion channel 734 adjacent to bottom surface 760 of chamber lid 732. In certain embodiments, the inner diameter of the expansion channel 734 for a substrate adapted to process a 200 mm diameter substrate is between about 0.2 inches (0.51 cm) and about 1.0 inches (2.54) at the top 737 of the expansion channel 734. cm), preferably between about 0.3 inch (0.76 cm) and about 0.9 inch (2.29 cm), more preferably between about 0.3 inch (0.76 cm) and about 0.5 inch (1.27 cm), and expansion channel 734 About 0.5 inches (1.27 cm) to about 3.0 inches (7.62 cm), preferably about 0.75 inches (1.91 cm) to about 2.5 inches (6.35 cm) at the bottom of 735, more preferably about 1.1 inches (2.79 cm) ) To about 2.0 inches (5.08 cm).

In another particular embodiment, the inner diameter of the expansion channel 734 for the chamber adapted to process a 300 mm diameter substrate is from about 0.2 inches (0.51 cm) to about 1.0 inches (2.54) at the top 737 of the expansion channel 734. cm), preferably between about 0.3 inch (0.76 cm) and about 0.9 inch (2.29 cm), more preferably between about 0.3 inch (0.76 cm) and about 0.5 inch (1.27 cm), and extend to a 300 mm substrate. About 0.5 inches (1.27 cm) to about 3.0 inches (7.62 cm), preferably about 0.75 inches (1.91 cm) to about 2.5 inches (6.35 cm) at the bottom 735 of the channel 734 Inches (2.79 cm) to about 2.0 inches (5.08 cm). Generally, the dimension applies to expansion channels adapted to provide a total flow rate in the range of about 500 sccm to about 3000 sccm.

In another particular embodiment, the dimensions can be changed to accommodate the particular gas flow through it. In general, large gas flows will require large diameter expansion channels. In one embodiment, the expansion channel 734 may be shaped like a truncated cone (including a shape resembling a truncated cone). Whether gas is provided downstream directly towards the wall of the expansion channel 734 or toward the substrate, the velocity of the gas flow decreases as the gas flow moves through the expansion channel 734 by expansion of the gas. Reducing the velocity of the gas flow helps similar to the gas flow to reduce blowing off of the absorbed reactants on the surface of the substrate 690.

Without being bound by theory, the diameter of the expansion channel 734, which gradually increases from the top 737 to the bottom 735 of the expansion channel 734, may reduce the adiabatic expansion of the gas through the expansion channel 734. This helps to control the temperature of the gas. For example, a sudden adiabatic expansion of the gas delivered through the gas inlets 736A, 736B to the expansion channel 734 can result in a drop in the temperature of the gas, which can lead to the formation of particles and densification of the precursor vapor. On the other hand, it is believed that a gradual expansion channel 734 according to an embodiment of the present invention is provided to eliminate adiabatic expansion of the gas. Thus, more heat can be transferred from or into the gas, and the temperature of the gas can be more easily controlled by controlling the ambient temperature of the gas (by controlling the temperature of the chamber lid 732). The progressive expansion channel 734 may include one or more pointed interior surfaces, such as pointed straight surfaces, concave surfaces, convex surfaces, or mixtures thereof, and may include one or more pointed interior surfaces (ie, pointed and non-pointed portions). It may include a section.

In one embodiment, gas inlets 736A, 736B are located adjacent the top 737 of the expansion channel 734. In other embodiments, one or more gas inlets 736A, 736B may be located along the length of the expansion channel 734 between the top 737 and the bottom 735. Without being bound by theory, the gas flowing from and through the gas inlets 736A, 736B into and into the expansion channel 734 of the chamber lid 732 forms a circular flow. Although the exact flow pattern through the expansion channel 734 is not known, circular flow may travel through the expansion channel 734 in a flow pattern such as vortex flow, helix flow, helical flow, or a derivative thereof. Circular flow may be provided in the process region located between the substrate receiving surface 691 and the bottom 735, as opposed in compartments separate from the substrate 690. In one aspect, the vortex flow can help ensure more effective purification of the expansion channel 734 by sweeping operations of circular flow across the inner surface of the expansion channel 734. In addition, the circular gas provides for a consistent and conformal gas delivery across the surface of the substrate 690.

In FIG. 7, a control unit 780, such as a programmed personal computer, workstation computer or the like, may be coupled to the process chamber 680 and thereby control the process conditions. For example, control unit 780 can be configured to control the flow of various process gases and purge gases from gas sources 738, 739, 740 through valves 742A, 742B during different stages of the substrate processing sequence. have. As shown, the control unit 780 includes a memory 786 containing a central processing unit (CPU) 782, a support circuit 784, and associated control software 783. The control unit 780 may also be configured to control the WVG system 286 and / or govern the ampoule 282.

Process unit 780 may be a form of general purpose computer processor, which may be industrially set and used to control various chambers and subprocessors. The CPU 782 may use appropriate memory, such as partial or remote, as random access memory, read only memory, floppy disk drive, compact disk drive, hard disk, or other form of digital storage device. Various support circuits may be coupled to the CPU 782 to support the process chamber 680. Control unit 780 may be coupled to another controller, which is located adjacent to individual chamber components, such as programmable logic controllers 748A and 748B of valves 742A and 742B. Bidirectional communication between the control unit 780 and various other components of the process chamber 680 is handled through a collective number of signal cables, called signal buses 788, some of which are shown in FIG. 7. In addition to the control of purge and process gases from the programmable logic controllers 748A, 748B of the valves 742A, 742B and from the gas sources 738, 739, 740, the control unit 780 includes wafer transfer, temperature It may be configured to be responsible for the automatic control of other activities used in wafer processing such as control, chamber emptying, some of which are described herein.

In other embodiments, the process chamber 680 is configured to receive three or more flows together, partially together (ie, two of three gas flows together), or individually through three or more gas inlets connected by three or more gas conduits. Can be applied. Each conduit is connected to one or multiple valves. A further disclosure of a process chamber 680 stored to flow three or more process gas flows was issued as US 20030079686, incorporated herein by reference, and entitled December 2001, entitled “Gas Delivery Apparatus and Method for Atomic Layer Deposition”. US patent application Ser. No. 10 / 032,284, filed May 21. In one example, the three gas flows may contain a hafnium precursor, a silicon precursor and an oxidizing gas, the first flow comprises TDEAH, TDMAH, HfCl 4, the second flow comprises TDMAS, Tris-DMAS, or silane, and Three flows contain an oxidizing gas containing water vapor from the WVG system.

8 shows a schematic cross-sectional view of a process chamber 810 that can be used to perform direct circuit fabrication in accordance with an embodiment described herein. Process chamber 810 is similar in function to process chamber 680 and contains a thermally insulating material that operates at high temperatures (eg, <800 ° C.). Process chamber 810 contains a liner made of a thermally insulating material such as fused quartz, sapphire, pyrolytic boron nitride (PBN) material, ceramic, derivatives thereof, or a combination thereof. In one embodiment, the gas delivery device 730 from the process chamber 680 may be adapted for use above the process chamber 810.

Process chamber 810 generally includes a substrate support pedestal 812 used to support substrate 802. The substrate support pedestal 812 is vertically movable and rotatable within the process chamber 810. The substrate support pedestal 812 may contain a heating element, thereby controlling the temperature of the substrate 802 thereon. Cap portion 872 is disposed over lid 832 of process chamber 810 and contains gas inlets 836a, 836b, 836c, 836d. Cap portion 872 may also contain an adapter 874 to a remote plasma device or microwave device used during a plasma process, such as a PE-ALD process, a pre-purification process or a nitrogenization process. Alternatively, adapter 874 is not present in cap portion 872.

Gas delivery system 811 is connected to process chamber 810 via cap portion 872. Gas delivery system 811 includes at least one and about ten of the gas inlet 836, conduit system 841, valve 843, and / or valve 845 and source 842 and / or source 844. Contains a set of components. As shown in FIG. 8, gas delivery system 811 includes gas inlets 836a, 836b, 836c, 836d, conduit systems 841a, 841b, 841c, 841d, valves 843a, 843b, 843c, 843d, and valves. 845a, 845b, 845c, 845d, and four component sets containing sources 842a, 842b, 842c, 842d and sources 844a, 844b, 844c, 844d.

In alternative embodiments, conduit system 841 may further include gradually expanding a gas conduit forming a nozzle at the end, which is also in fluid communication with gas inlets 836a, 836b, 836c, 836d. Located. A nozzle or end useful in one embodiment described herein is US patent application Ser. No. 11 / 119,388, filed April 29, 2005 entitled "Control of Gas Flow and Delivery to Inhibit Particle Formation in MOCVD / ALD Systems." It is further described in the call. The gas conduit geometry prevents large temperature drops by providing gas through, and the means gradually expand through an increasing tapered flow channel. In one embodiment, a gas inlet 836 having a large diameter in the range of about 10 mm to about 20 mm over a distance in the range of about 30 mm to about 100 mm from a cross section of the delivery gas line having an internal diameter in the range of about 3 mm to about 15 mm. ), The flow channel is varied. The gradual increase in the diameter of the flow channel prevents the rapid loss of heat to keep the inflation gas nearly equilibrium and maintain a nearly constant temperature. The inflation gas conduit may include one or more pointed inner surfaces, such as pointed straight surfaces, concave surfaces, convex surfaces, or mixtures thereof, and includes sections of one or more pointed inner surfaces (ie, pointed and non-pointed portions). can do.

Conduit system 841 contains one or more conduits and tubes connecting gas inlet 836, valves 843, 845, and sources 842, 844. Valve 843 controls the inflow of precursor or gas from source 842 to gas inlet 836, and valve 845 controls the inflow of precursor or gas from source 844 to gas inlet 836. . The valves 843, 845 can include a valve and valve seat assembly containing a diaphragm and a valve seat. Pneumatically actuated valves provide a pulse of gas at a time period as low as about 0.020 seconds. The electrically driven valve provides a pulse of gas at a time period as low as about 0.005 seconds. In general, pneumatically and electrically driven valves can provide pulses of gas with a high time period of about 3 seconds. Higher time periods for gas pulsing are possible, but a typical ALD process requires an ALD valve, which opens for an interval of about 5 seconds or less, preferably about 3 seconds or less, more preferably about 2 seconds or less. Generate a pulse of gas. In one embodiment, the ALD valve provides a pulse at intervals ranging from about 0.005 seconds to about 3 seconds, preferably from about 0.02 seconds to about 2 seconds, more preferably from about 0.05 seconds to about 1 second. Electrically driven valves generally require the use of a driver coupled between the valve and the programmable logic controller. A control unit (not shown), such as a programmed personal computer, workstation computer, or the like, may include a valve 843, 845, a source 842, 844, a vacuum system 833, a substrate support 812, a WVG system ( 286 and ampoule 282 may be included in the process chamber 810, thereby controlling process conditions as described herein.

Sources 842 and 844 may provide precursor sources, purge gas sources, and / or carrier gas sources for use during the deposition process. The precursor source may comprise one or more precursors (eg, hafnium precursors and silicon precursors) and may include a carrier gas. Precursor sources include ampoules, bubblers, tanks, containers, or cartridges. The precursor source also includes a water vapor generator (WVG) system, which is in fluid communication with the gas delivery system 811 described herein. The purge gas source and / or carrier gas source is generally a tank, container, cartridge or in-house plumbed supply system, which is a gas delivery system 811 that is nitrogen, argon, helium, hydrogen , Molding gas or combinations thereof may be provided.

Gas inlets 836a, 836b, 836c, 836d may be located along the length of expansion channel 834 within cap portion 872. Without being bound by theory, the gas flowing from and through the expansion channel 834 to the gas inlets 836a, 836b, 836c, 836d is in the form of a circular flow. Although the exact flow pattern through the expansion channel 834 is not known, circular flow may travel through the expansion channel 834 in a flow pattern such as vortex flow, helix flow, helical flow, or a derivative thereof. Circular flow may be provided in the process area located between the substrate support 812 and the funnel liner opposite the compartment separated from the substrate 802. In one aspect, the vortex flow can help establish more effective purification of the process area by the sweeping action of the circular flow across the inner surface of the expansion channel 834. In addition, the circular gas provides constant and conformal delivery of the gas across the surface of the substrate 802.

8 and 9A-9B show schematic diagrams of thermally insulating liners that may be used within other process chambers and process chambers 810 during the deposition process described herein. Expansion channels 834 may be formed between funnel liner 820 and in cap portion 872. Thermal insulator 870 is disposed around cap portion 872. The funnel liner 820 is formed by supporting the ring liner 819 by aligning the ledge surface 817 supporting the ring liner 819 together with the ledge surface 818 of the funnel liner 820. 832 may be supported against the bottom. Supporting the ring liner 819 may be attached to the bottom of the lid 832 by a clamp 837, such as a fitting, bolt, screw or pin. In one example, the clamp 837 is a fitting that is fitted and inserted into the groove 816 that bears the ring liner 819. In addition, the funnel liner 820 may contain a number of fins 838, which are loosely fitted, thereby providing freedom to the funnel liner 820, thereby thermally expanding during the heating process. In one embodiment the funnel liner 820 is thermally inflated and then aligned with the substrate 802. Alternatively, funnel liner 820 and supporting ring liner 819 may be formed as one component.

Process chamber 810 may additionally contain an upper process liner 822 and a lower process liner 824. The lower process liner 824 is disposed above the lower surface 827, and the upper process liner 822 is disposed along the wall surface 830 of the chamber body 803 and above the lower process liner 824. Slip valve liner 826 is positioned to push into process region 815 and through upper process liner 822. The liner, which includes the funnel liner 820, the support ring liner 819, the upper process liner 822, the lower process liner 824, and the slip valve liner 826, is a fused quartz, sapphire, pyrolytic boron PBN material. Thermally insulating materials such as ceramics, derivatives thereof or combinations thereof. In general, the liner is stressed and relaxed and prevents failure of the thermal cycle during the start and cooling cycles of the deposition process described herein. The liner may withstand a temperature of about 800 or more, preferably about 1000 ° C. or more, more preferably about 1200 ° C. or more. In addition, the liner is flame polished to achieve a surface finish of about 2 microinches (about 0.051 μm) or less. The polished finish provides a smooth surface whereby the process reactants are delivered with little or no disturbance and minimize nucleation sites on the liner that can promote unwanted film growth on the liner. Flame polishing also eliminates surface defects (eg pit, cracks) to minimize nucleation of thermally stressed cracks.

Purification line 829 is a chamber rear purge line disposed from the bottom of chamber body 803 to chamber lid 832 and funnel liner 820. Purification line 829 is positioned between the wall 830 and the lower / top process liners 822, 824 to enable flow of purge gas into the process region 815. The source of purge gas may be connected to purge line 829 through inlet 804. The purge gas flowing through the purge line 826 buffers the wall surface 830 from contaminants and excess heat, which may exit the process region 815. The contaminants include products of precursors or reactants, which can bypass the upper / lower process liners 822, 824 and are thereby deposited on the wall 830. In addition, heat generated from the process region 815 may be avoided and absorbed into the process body 803. The flow of purge gas flowing through the purge line 826 transports contaminants and heat back into the process region 815. Thermal choke plate 809 is disposed outside of chamber body 803, thereby preventing heat loss from process region 815.

9B shows a schematic diagram of an upper process liner 822, a lower process liner 824, and a slip valve liner 826. Upper process liner 822 and lower process liner 824 may contain lift pin holes 821, 823, thereby receiving a substrate lift pin (not shown) during movement of substrate 802. Upper process liner 822 and lower process liner 824 are positioned in the process chamber to align lift pin hole 821 with lift pin hole 823. The upper process liner 822 also includes a vacuum port 835 for receiving the outlet adapter 831 and a slit valve port 825 for receiving the slit valve liner 826. Discharge adapter 831 is located through chamber body 803 and vacuum port 835, whereby process region 815 is in fluid communication with vacuum system 833. The substrate passes through the slit valve liner 826, thereby entering and exiting the process chamber 810. Slit valve liner 826 may also protrude through thermal choke plate 809.

Pumping efficiency may be controlled using choke gap 840. Choke gap 840 is a space formed between the bottom edge of funnel liner 820 and the top of substrate support pedestal 812. The choke gap 840 is a circumferential gap, which can be changed depending on the pumping efficiency and process conditions required. The choke gap 840 is increased by lowering the substrate support pedestal 812 or is reduced by raising the substrate support pedestal 812. The pumping conductivity from the pumping port (not shown) to the center of the expansion channel 834 at the bottom of the process chamber 810 is changed by varying the distance of the choke gap 840, thereby during the deposition process described herein. Control the uniformity and thickness of the film.

10 shows a schematic diagram of a process chamber lid assembly 1050 that may be used over the ALD process chamber described herein. In one example, the lid assembly 1050 can replace the lid 832 and the gas delivery system 811 over the process chamber 810. In another example, the lid assembly 1050 can replace the lid 732 and the gas delivery device 730 above the process chamber 680. Reed assembly 1050 includes a valve manifold support 1030 disposed on reed 1032. Thermal insulators 1002a and 1002b separate valve manifold support 1030 from leads 1032 and cause some heat dissipation therefrom. Conduits 1020 and 1022 traverse through leads 1032, thereby providing fluid communication into the process chamber from an external source or device. The valve manifold support 1030 includes an adapter 1074, valves 1043a, 1043b, 1043c and 1043d and valves 1045a, 1045b, 1045c and 1045d. Adapter 1074 supports a remote plasma device or microwave device used during a plasma process such as a nitrogenization process or a pre-clean process, PE-ALD process. The valves 1043a, 1043b, 1043c, 1043d and the valves 1045a, 1045b, 1045c, 1045d are connected by a conduit system (not shown) within the valve manifold support 1030. The precursor source, purge gas source, and / or carrier gas source are in fluid communication with the process chamber through the lid assembly 1050 during the deposition process. In one example, the lid assembly 1050 is piped to have a conduit system similar to the conduit system 841 in the gas delivery system 811.

As used herein, “substrate surface” means any substrate or material surface formed on a substrate, on which a process is performed. For example, the substrate surface on which the process can be carried out may have different conductive materials, metal alloys, metal nitrides, other materials such as metals, sapphire, glass, gallium arsenide, germanium, doped silicon, silicon nitride , Materials such as carbon doped silicon oxide, silicon on insulator (SOI), modified silicon, silicon oxide, silicon. Barrier layers of metal or metal nitride on the substrate surface include titanium, titanium nitride, tungsten nitride, tantalum, and tantalum nitride. The substrate may have various dimensions, such as a 200 mm to 300 mm diameter wafer, rectangular or square plate. The process of the embodiments described herein deposits hafnium-containing materials over many substrates and surfaces. Embodiments of the present invention may include a substrate, which is not limited to semiconductor substrates, and includes crystalline silicon (eg, Si <100>, Si <111>), silicon oxide, modified silicon, silicon germanium, doped or Undoped polysilicon, doped or undoped silicon wafers, and wafers with or without patterns. The substrate is exposed to a pretreatment process to polish, etch, reduce, oxidize, hydrooxylate, anneal and / or bake the substrate surface.

As used herein, “atomic layer deposition” or “cyclic deposition” refers to the sequential influx of two or more compounds and thereby deposits a layer of material on the substrate surface. Two, three or more reactive compounds may alternatively be introduced into the reaction zone of the process chamber. In general, each reaction compound is separated by a time delay, thereby allowing each compound to react and / or adhere on the substrate surface. In one aspect, the first precursor or compound (A) is pulsed into the reaction zone followed by a first time delay. The second precursor or compound (B) is then pulsed into the reaction zone followed by a second time delay. During each time delay, purge gas, such as nitrogen, is introduced into the process chamber, thereby removing residual reaction compounds or by-products from the reaction zone or purifying the reaction zone. Alternatively, the purge gas can flow continuously through the deposition process, whereby only the purge gas flows during the time delay between pulses of the reactive compound. The reactive compound is alternatively pulsed until the desired film or film thickness is formed on the substrate surface. In each case, the ALD process of pulsing compound (A), purge gas, pulsing compound (B) and purge gas is a cycle. The cycle starts with compound (A) or compound (B) and continues the individual sequence of cycles until a film of the desired thickness is obtained. In another embodiment, the first precursor containing Compound (A), the second precursor containing Compound (B), and the third precursor containing Compound (C) are each separated and pulsed into the process chamber. Alternatively, the pulses of the first precursor may overlap in time with the pulses of the second precursor, and the pulses of the third precursor do not overlap in time with the pulses of the first and second precursors.

Yes

For Examples 1-10, the ALD process is maintained at a temperature of about 70 ° C to about 1000 ° C, preferably about 100 ° C to about 650 ° C, for example about 350 ° C. The ALD process may be performed at a pressure in the process chamber in the range of about 0.1 Torr to about 100 Torr, preferably about 1 Torr to about 10 Torr. The carrier gas (eg N2) may have a flow rate of about 2 sim to about 22 sim, preferably about 10 sim. The oxidizing gas containing water vapor is produced by a water vapor generator (WVG) system containing a metal catalyst available from Fujikin of America, Inc., located in Santa Clara, California. The WVG system formed oxidizing gas from a hydrogen source gas and an oxygen source gas. The substrate was exposed to oxidizing gas containing water vapor from the WVG system during the pre-treatment process. The pre-treatment process was run for a period ranging from about 5 seconds to about 30 seconds. The deposited material is formed to a thickness in the range from about 2 kPa to about 1000 kPa, preferably from about 5 kPa to about 100 kPa, more preferably from about 10 kPa to about 50 kPa.

Example 1-A hafnium oxide film is formed by sequentially pulsing a hafnium precursor with an oxidizing gas produced by a WVG system. The substrate surface is exposed to the pretreatment process thereby forming hydroxyl groups thereon. Hafnium precursor (HfCl 4) is heated in the precursor ampoule at a temperature ranging from about 150 ° C. to about 200 ° C. The nitrogen carrier gas is led to a precursor ampoule containing a hafnium precursor having a flow rate of about 400 sccm. Hafnium precursor saturates the carrier gas and is provided into the chamber for about 3 seconds. A purge gas of nitrogen is provided into the chamber for about 2.5 seconds to thereby remove unbound hafnium precursor. Hydrogen gas and oxygen gas having flow rates of about 100 sccm and about 120 sccm, respectively, are fed to the WVG system. The oxidizing gas from the WVG system contains water having a flow rate of about 100 sccm and oxygen having a flow rate of about 70 sccm. The oxidizing gas is provided into the chamber for about 1.7 seconds. The purge gas of nitrogen is provided into the chamber for about 2.5 seconds, thereby removing unbound or unreacted reactants such as byproducts, hafnium precursors, oxygen and / or water or byproducts such as HCl. Each ALD cycle forms about 1 GPa of hafnium oxide film.

Example 2-A hafnium oxide film is formed during an ALD process by sequentially pulsing a hafnium precursor with an oxidizing gas. The substrate surface is exposed to a pretreatment process to form hydroxyl groups thereon. Hafnium precursor (HfCl 4) is heated in the precursor ampoule at a temperature in the range of about 150 ° C. to about 200 ° C. The nitrogen carrier gas is led into the precursor ampoule containing the hafnium precursor at a flow rate of about 400 sccm. The hafnium precursor saturates the carrier gas and is provided into the chamber for about 0.5 seconds. A purge gas of nitrogen is provided into the chamber for about 0.5 seconds to thereby remove the unbound hafnium precursor. Hydrogen and oxygen gases with flow rates of about 50 sccm and about 60 sccm, respectively, are fed to the WVG system. The oxidizing gas generated from the WVG system contains water having a flow rate of about 50 sccm and oxygen having a flow rate of about 35 sccm. Oxidation gas is provided into the chamber for about 0.5 seconds. The nitrogen purge gas is provided into the chamber for about 0.5 seconds, thereby removing byproducts such as hafnium precursor, oxygen and / or water or HCl. Each ALD cycle forms about 2.5 kW of hafnium oxide film.

Example 3 A hafnium silicate film is formed during an ALD process by sequentially pulsing a hafnium precursor with an oxidizing gas and then pulsing the silicon precursor with an oxidizing gas. The substrate surface is exposed to the pretreatment process thereby forming hydroxyl groups thereon. Hafnium precursor, TDEAH and silicon precursor, TDMAS, are heated in individual precursor ampoules at room temperature (about 23 ° C.). These precursors are individually evaporated in an evaporator of about 110 ° C. to about 300 ° C. and mixed separately with the inert carrier gas. Hafnium precursor saturates the carrier gas and is provided into the chamber for about 1 second. A purge gas of nitrogen is provided into the chamber for about 1 second, thereby removing unbound hafnium precursor. Hydrogen and oxygen gases with flow rates of about 100 sccm and about 120 sccm, respectively, are fed to the WVG system. The oxidizing gas generated from the WVG system contains water having a flow rate of about 100 sccm and oxygen having a flow rate of about 70 sccm. The oxidizing gas is provided into the chamber for about 1.7 seconds. A purge gas of nitrogen is provided into the chamber for about 5 seconds to remove unreacted or unbound reactants such as hafnium precursors, oxygen and / or water or byproducts. The silicon precursor is provided into the chamber for about 1 second. The purge gas of nitrogen is provided into the chamber for about 1 second to thereby remove any unbound precursors or contaminants. The oxidizing gas is provided into the chamber for about 1.7 seconds. The purge gas of nitrogen is provided into the chamber for about 5 seconds. Each ALD cycle forms about 1 ms of hafnium silicate film.

Example 4 A hafnium silicate film is formed during an ALD process by sequentially pulsing a hafnium precursor with an oxidizing gas and then pulsing the silicon precursor with an oxidizing gas. The substrate surface is exposed to a pretreatment process to form hydroxyl groups thereon. Hafnium precursor (HfCl 4) and silicon precursor (Tris-DMAS) are heated in separate precursor ampoules at room temperature (about 23 ° C.). These precursors are individually evaporated in the evaporator at about 110 ° C. to about 130 ° C. and mixed separately with the inert carrier gas. Hafnium precursor saturates the carrier gas and is provided into the chamber for about 1 second. The purge gas of nitrogen is provided into the chamber for about 1 second. Hydrogen and oxygen gases with flow rates of about 100 sccm and about 120 sccm, respectively, are fed to the WVG system. The oxidizing gas generated from the WVG system contains water having a flow rate of about 100 sccm and oxygen having a flow rate of about 70 sccm. The oxidizing gas is provided into the chamber for about 1.7 seconds. The purge gas with nitrogen is provided into the chamber for about 1 second thereby removing unreacted or unbound reactants such as hafnium precursors, oxygen and / or water. The silicon precursor is provided into the chamber for about 1 second. The purge gas of nitrogen is provided into the chamber for about 1 second thereby removing unbound precursors or contaminants. The oxidizing gas is provided into the chamber for about 1.7 seconds. The purge gas of nitrogen is provided into the chamber for about 5 seconds. Each ALD cycle forms about 1 ms of hafnium silicate film.

Example 5-A hafnium silicate film is formed during an ALD process by simultaneously pulsing hafnium precursor and silicon precursor simultaneously with oxidizing gas. The substrate surface is exposed to a pretreatment process to form hydroxyl groups thereon. Hafnium precursor, TDEAH, and silicon precursor, TDMAS, are heated in individual precursor ampoules at room temperature (about 23 ° C.). These precursors are individually evaporated in the evaporator at about 110 ° C. to about 130 ° C. and mixed separately in an inert carrier gas. Each of the hafnium precursor and the silicon precursor are simultaneously provided into the chamber for about 1 second. A purge gas of nitrogen is provided into the chamber for about 1 second to remove unbound hafnium or silicon precursors. Hydrogen and oxygen gases with flow rates of about 100 sccm and about 120 sccm, respectively, are fed to the WVG system. The oxidizing gas generated from the WVG system contains water having a flow rate of about 100 sccm and oxygen having a flow rate of about 70 sccm. The oxidizing gas is provided into the chamber for about 1.7 seconds. A purge gas of nitrogen is provided into the chamber for about 5 seconds to remove unbound or unreacted reactants such as byproducts, hafnium precursors, silicon precursors, oxygen and / or water. Each ALD cycle forms about 1 ms of hafnium silicate film.

Example 6-A hafnium silicate film is formed during an ALD process by simultaneously pulsing a silicon precursor and a hafnium precursor sequentially with an oxidizing gas. The substrate surface is exposed to a pretreatment process to form hydroxyl groups thereon. Hafnium precursor, HfCl ₄ , and silicon precursor, Tris-DMAS, are heated in individual precursor ampoules at room temperature (about 23 ° C.). These precursors are individually evaporated in the evaporator at about 110 ° C. to about 130 ° C. and mixed separately in an inert carrier gas. Each of the hafnium precursor and the silicon precursor are simultaneously provided into the chamber for about 1 second. A purge gas of nitrogen is provided into the chamber for about 1 second to remove unbound hafnium or silicon precursors. Hydrogen and oxygen gases with flow rates of about 100 sccm and about 120 sccm, respectively, are fed to the WVG system. The oxidizing gas generated from the WVG system contains water having a flow rate of about 100 sccm and oxygen having a flow rate of about 70 sccm. The oxidizing gas is provided into the chamber for about 1.7 seconds. A purge gas of nitrogen is provided into the chamber for about 5 seconds to remove unbound or unreacted reactants such as byproducts, hafnium precursors, silicon precursors, oxygen and / or water. Each ALD cycle forms about 1 ms of hafnium silicate film.

Example 7-A hafnium oxide film is grown in an ALD process by sequentially pulsing a hafnium precursor with in-situ steam formed from a WVG system. The substrate surface is exposed to a pretreatment process to form hydroxyl groups thereon. Hafnium precursor (HfCl 4) is heated in the precursor ampoule at a temperature of about 150 ° C. to about 200 ° C. The nitrogen carrier gas is directed into the precursor ampoule containing the hafnium precursor with a flow rate of about 400 sccm. Hafnium precursor saturates the carrier gas and is provided into the chamber for about 1.5 seconds. A purge gas of nitrogen is provided into the chamber for about 2.5 seconds to remove unbound hafnium precursor. Molding gas (5% by volume H2 balanced with N2) and oxygen gas, each having a flow rate of about 100 sccm, are fed to the WVG system. The oxidizing gas generated from the WVG system contains water having a flow rate of about 2.5 sccm and oxygen having a flow rate of about 98 sccm. The oxidizing gas is supplied to the chamber for about 1.7 seconds. The purge gas of nitrogen is provided to the chamber for about 2.5 seconds to remove unbound or unreacted reactants such as by-products, hafnium precursors, oxygen and / or water.

Example 8-A hafnium silicate film is formed by sequentially pulsing a hafnium precursor with an oxidizing gas and then pulsing the silicon precursor with an oxidizing gas. The substrate surface is exposed to the pretreatment process thereby forming hydroxyl groups thereon. Hafnium precursor, TDEAH and silicon precursor, TDMAS, are heated in individual precursor ampoules at room temperature (about 23 ° C.). These precursors are individually evaporated in an evaporator of about 110 ° C. to about 300 ° C. and mixed separately with the inert carrier gas. Hafnium precursor saturates the carrier gas and is provided into the chamber for about 1 second. A purge gas of nitrogen is provided to the chamber for about 1 second to remove unbound hafnium precursor. Molding gas (5% by volume H2 balanced with N2) and oxygen gas are each fed to the WVG system at a flow rate of about 100 sccm. The oxidizing gas is provided into the chamber for about 1.7 seconds. A purge gas of nitrogen is provided into the chamber for about 5 seconds to remove unreacted or unbound reactants such as hafnium precursors, oxygen and / or water or byproducts. The silicon precursor is provided into the chamber for about 1 second. The purge gas of nitrogen is provided into the chamber for about 1 second to thereby remove any unbound precursors or contaminants. The oxidizing gas is provided into the chamber for about 1.7 seconds. The purge gas of nitrogen is provided into the chamber for about 5 seconds. Each ALD cycle forms about 1 ms of hafnium silicate film.

Example 9-A hafnium precursor is formed during an ALD process by simultaneously pulsing a silicon precursor and a hafnium precursor sequentially with an oxidizing gas. The substrate surface is exposed to a pretreatment process to form hydroxyl groups thereon. Hafnium precursor, TDEAH, and silicon precursor, TDMAS, are heated in individual precursor ampoules at room temperature (about 23 ° C.). This precursor is evaporated separately in the evaporator at about 110 ° C. to about 130 ° C. and mixed separately with the inert carrier gas. The hafnium precursor and the silicon precursor are each pulsed simultaneously into the chamber for about 1 second. A purge gas of nitrogen is provided into the chamber for about 1 second thereby removing unbound hafnium or silicon precursors. Molding gas (0.5% by volume H2 balanced with N2) and oxygen gas are each fed to the WVG system at a flow rate of about 100 sccm. The oxidizing gas generated from the WVG system contains water with a flow rate of about 0.25 sccm and oxygen with a flow rate of about 100 sccm. The oxidizing gas is provided into the chamber for about 1.7 seconds. A purge gas of nitrogen is provided into the chamber for about 5 seconds to remove unbound or unreacted reactants such as byproducts, hafnium precursors, silicon precursors, oxygen and / or water. Each ALD cycle forms about 1 ms of hafnium silicate film.

Example 10-A hafnium oxide film is formed during an ALD process by sequentially pulsing a hafnium precursor with an oxidizing gas produced by a WVG system. The substrate surface is exposed to a pretreatment process to form hydroxyl groups thereon. Hafnium precursor, TDEAH, is heated in the precursor ampoule at a temperature of about 23 ° C. Nitrogen gas is led into the precursor ampoule containing the hafnium precursor at a flow rate of about 400 sccm. Hafnium precursor saturates the carrier gas and is provided into the chamber for about 2 seconds. A purge gas of nitrogen is provided into the chamber for about 1.5 seconds to remove unbound hafnium precursor. Hydrogen gas and oxygen gas having flow rates of about 100 sccm and about 120 sccm, respectively, are fed to the WVG system. The oxidizing gas resulting from the WVG system contains water having a flow rate of about 100 sccm and oxygen having a flow rate of about 70 sccm. The oxidizing gas is provided into the chamber for about 1.7 seconds. A purge gas of nitrogen is provided into the chamber for about 1.5 seconds to remove unbound or unreacted reactants such as by-products, hafnium precursors, oxygen and / or water. Each ALD process forms a hafnium oxide film of about 1.1 GPa.

The materials are alternately deposited by dosing each chemical, thereby obtaining the desired film composition or characteristics in the selected reaction. The reaction does not dictate the exact bond linkage or stoichiometry of the resulting film. Most of the stoichiometry of the product composition is thermodynamically controlled during the chemical reaction, and the stoichiometry of the product composition can also be controlled dynamically to obtain the desired composition. Thus, the order of dosing may be altered, thereby affecting the overall composition and quality of the film.

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

Claims (30)

A method for forming a hafnium-containing material on a substrate located in a process chamber, the method comprising: Exposing the substrate to a hafnium precursor to form a hafnium-containing layer over the substrate; Purifying the process chamber with a purge gas; Exposing the substrate to an oxidizing gas to form a hafnium oxide material on the substrate; And Purifying the process chamber with the purge gas, The oxidizing gas comprises water vapor formed by flowing an oxygen source gas and a hydrogen source gas through a steam generator, A method for forming a hafnium-containing material over a substrate located in a process chamber. The method of claim 1, The hydrogen source gas comprises hydrogen gas, A method for forming a hafnium-containing material over a substrate located in a process chamber. The method of claim 2, Wherein the oxygen source gas comprises an oxygen compound selected from the group consisting of oxygen, nitrous oxide and combinations thereof A method for forming a hafnium-containing material over a substrate located in a process chamber. The method of claim 3, wherein The oxygen compound flows into the water generator at a faster rate than the hydrogen gas, A method for forming a hafnium-containing material over a substrate located in a process chamber. The method of claim 4, wherein Wherein the oxidizing gas further comprises an oxygen gas, A method for forming a hafnium-containing material over a substrate located in a process chamber. The method of claim 2, The hydrogen source gas is a forming gas, A method for forming a hafnium-containing material over a substrate located in a process chamber. The method of claim 6, Wherein the forming gas has a hydrogen gas concentration in the range of about 1% by volume to about 30% by volume, A method for forming a hafnium-containing material over a substrate located in a process chamber. The method of claim 1, Prior to exposing the substrate to the hafnium precursor, exposing the substrate to a soak process containing the oxidizing gas for a time period ranging from about 5 seconds to about 30 seconds, A method for forming a hafnium-containing material over a substrate located in a process chamber. The method of claim 1, Depositing a silicon oxide material over the hafnium oxide material, and depositing the silicon oxide material, Exposing the substrate to a silicon precursor to form a silicon containing layer on the substrate; Purifying the process chamber with the purge gas; Exposing the substrate to the oxidizing gas to form a silicon oxide material over the substrate; And Purifying the process chamber with the purge gas, A method for forming a hafnium-containing material over a substrate located in a process chamber. A method of depositing hafnium-containing material on a substrate during an atomic layer deposition process, the method comprising: Positioning the substrate in the process chamber; Flowing the hydrogen source gas and the oxygen source gas to a steam generator to generate an oxidizing gas comprising steam; And Sequentially exposing the substrate to a process gas comprising the oxidizing gas and a hafnium precursor to form a hafnium-containing material over the substrate, A method of depositing hafnium-containing material over a substrate during an atomic layer deposition process. The method of claim 10, Wherein the hydrogen source gas comprises hydrogen gas, A method of depositing hafnium-containing material over a substrate during an atomic layer deposition process. The method of claim 11, Wherein the oxygen source gas comprises an oxygen compound selected from the group consisting of oxygen, nitros oxides and combinations thereof A method of depositing hafnium-containing material over a substrate during an atomic layer deposition process. The method of claim 12, The oxygen compound flows into the water generator at a faster rate than the nitrogen gas, A method of depositing hafnium-containing material over a substrate during an atomic layer deposition process. The method of claim 13, Wherein the oxidizing gas further comprises an oxygen gas, A method of depositing hafnium-containing material over a substrate during an atomic layer deposition process. The method of claim 11, The hydrogen source gas is a forming gas, A method of depositing hafnium-containing material over a substrate during an atomic layer deposition process. The method of claim 15, Wherein the forming gas has a hydrogen gas concentration in the range of about 1% by volume to about 30% by volume, A method of depositing hafnium-containing material over a substrate during an atomic layer deposition process. The method of claim 10, The hafnium-containing material is selected from the group consisting of hafnium oxide, hafnium silicate, hafnium silicon oxynitride, hafnium oxynitride, hafnium aluminate, derivatives thereof and combinations thereof A method of depositing hafnium-containing material over a substrate during an atomic layer deposition process. The method of claim 17, Wherein the process gas further comprises a silicon precursor or an aluminum precursor, A method of depositing hafnium-containing material over a substrate during an atomic layer deposition process. The method of claim 10, Exposing the substrate to a soak process containing the oxidizing gas for a period of time ranging from about 5 seconds to about 30 seconds, prior to forming the hafnium-containing material; A method of depositing hafnium-containing material over a substrate during an atomic layer deposition process. A method for forming a dielectric material over a substrate during an atomic layer deposition process, the method comprising: Positioning the substrate in the process chamber; Flowing the hydrogen source gas and the oxygen source gas to a steam generator to form an oxidizing gas comprising steam; And Sequentially exposing the substrate to the oxidizing gas and one or more precursors to form a dielectric material over the substrate, A method for forming a dielectric material over a substrate during an atomic layer deposition process. The method of claim 20, The at least one precursor is selected from the group consisting of hafnium precursor, zirconium precursor, silicon precursor, aluminum precursor, tantalum precursor, titanium precursor, lanthanum precursor, and combinations thereof A method for forming a dielectric material over a substrate during an atomic layer deposition process. The method of claim 21, The dielectric material is hafnium oxide, hafnium silicate, zirconium oxide, zirconium silicate, lanthanum oxide, lanthanum silicate, tantalum oxide, tantalum silicate, titanium oxide, titanium silicate, aluminum oxide, aluminum silicate, silicon oxide, derivatives thereof and combinations thereof. Comprising one or more materials selected from the group consisting of: A method for forming a dielectric material over a substrate during an atomic layer deposition process. The method of claim 20, Prior to forming the dielectric material, exposing the substrate to a soak process containing the oxidizing gas for a period of time ranging from about 5 seconds to about 30 seconds, A method for forming a dielectric material over a substrate during an atomic layer deposition process. A method for depositing hafnium silicate material on a substrate during an atomic layer deposition process, the method comprising: Positioning the substrate in the process chamber; Flowing the hydrogen source gas and the oxygen source gas to a steam generator to form an oxidizing gas comprising water vapor; And Sequentially exposing the substrate to a process gas comprising a hafnium precursor and a silicon precursor and the oxidizing gas to form a hafnium silicate material on the substrate, A method for depositing hafnium silicate material over a substrate during an atomic layer deposition process. The method of claim 24, Wherein the process gas is formed by combining a first gas containing the hafnium precursor and a second gas containing the silicon precursor in the process chamber, A method for depositing hafnium silicate material over a substrate during an atomic layer deposition process. The method of claim 24, Wherein the process gas is formed by evaporating a reactant mixture containing the hafnium precursor and the silicon precursor, A method for depositing hafnium silicate material over a substrate during an atomic layer deposition process. A method for forming a hafnium-containing dielectric stack over a substrate in a process chamber, the method comprising: Flowing a hydrogen source gas and an oxygen source gas into a steam generator to generate an oxidizing gas comprising steam; And Forming at least one hafnium silicate layer and at least one hafnium oxide layer over the substrate, wherein the forming step comprises: Sequentially exposing the substrate to a first process gas comprising a hafnium precursor and the oxidizing gas to form a first hafnium-containing material on the substrate; And Sequentially exposing the substrate to a second process gas comprising the hafnium precursor and the oxidizing gas to form a second hafnium-containing material over the first hafnium-containing material, A method for forming a hafnium-containing dielectric stack over a substrate in a process chamber. The method of claim 27, Wherein the first process gas further comprises a silicon precursor, A method for forming a hafnium-containing dielectric stack over a substrate in a process chamber. The method of claim 27, Wherein the second process gas further comprises a silicon precursor, A method for forming a hafnium-containing dielectric stack over a substrate in a process chamber. The method of claim 28, Prior to forming the first hafnium-containing material, the substrate is exposed to a soak process containing the oxidizing gas for a time period in the range of about 5 seconds to about 30 seconds, A method for forming a hafnium-containing dielectric stack over a substrate in a process chamber.

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