KR20180093832A - Selective deposition of aluminum and nitrogen containing material - Google Patents

Abstract

Provided are methods for selectively depositing an AI and N containing material for a second dielectric surface of a substrate on a first conductive surface of the same substrate. In some aspects, methods for forming an AI and N containing protective layer or an etch stop layer for use in an integrated circuit fabrication are provided. The methods comprise selectively depositing AIN on a first substrate relative to a second surface; and etching the deposited AIN.

Description

Selective deposition of aluminum and nitrogen containing materials [

Cross reference of related application

This application is a continuation-in-part of U.S. Serial No. 14 / 819,274 entitled " Selective Deposition of Aluminum and Nitrogen-containing Materials ", the entire disclosure of which is incorporated herein by reference. This application is also related to U.S. Provisional Application No. 62 / 438,055 entitled " Atomic Layer Etching Method ", the entire disclosure of which is incorporated herein by reference.

The present invention relates to the selective deposition of aluminum and nitrogen containing materials, such as Al and N-containing thin films, on a first surface relative to a second surface of the substrate.

Currently, integrated circuits are manufactured by a sophisticated process in which a variety of material layers are sequentially arranged in a predetermined arrangement on a substrate.

Certain arrangements of material layers on the substrate are often made by depositing material on the entire substrate surface and then removing the material from certain areas of the substrate, e.g., by deposition of a mask layer and subsequent selective etching processes.

In certain cases, the number of steps involved in fabricating the integrated circuit on the substrate can be reduced by using a selective deposition process, in order to eliminate the need for a subsequent process or to reduce the need for a subsequent process A material is selectively deposited on the relative first surface. Methods for selective deposition on a first surface of a substrate relative to a second surface of the substrate are disclosed herein.

In some embodiments, methods are provided for selectively depositing a material comprising aluminum and nitrogen. In some embodiments, a material comprising aluminum and nitrogen is deposited on a first surface of the same substrate relative to a second dielectric surface of the substrate in a method comprising at least one deposition cycle, Contacting the substrate with a first gaseous precursor comprising aluminum and contacting the substrate with a second gaseous precursor comprising nitrogen. In some embodiments, a material comprising aluminum and nitrogen is deposited on a first surface of the same substrate relative to a second Si-O surface of the substrate in a method comprising at least one deposition cycle, Contacting the substrate with a first gaseous precursor comprising aluminum and contacting the substrate with a second gaseous precursor comprising nitrogen. In some embodiments, a material comprising aluminum and nitrogen is deposited on a first surface of the same substrate relative to a second non-conductive surface of the substrate in a method comprising at least one deposition cycle, Contacting the substrate with a first gaseous precursor comprising aluminum and contacting the substrate with a second gaseous precursor comprising nitrogen. In some embodiments, the material comprising aluminum and nitrogen is deposited with a selectivity in excess of about 50% on the first surface of the same substrate relative to the second dielectric surface of the substrate. In some embodiments, the first surface comprises at least one of copper, titanium nitride, tungsten, and silicon nitride. In some embodiments, the material comprising aluminum and nitrogen is an aluminum nitride film. In some embodiments, the aluminum nitride film comprises oxygen.

In some embodiments, the first gaseous precursor is an organometallic aluminum compound. In some embodiments, the first gaseous precursor comprising aluminum does not comprise any metals other than aluminum. In some embodiments, the first gaseous precursors comprising aluminum having the formula R ₃ Al, R each of which may be independently selected from C ₁ -C ₄ alkyl group. In some embodiments, the first gaseous precursor comprising aluminum does not comprise a halide. In some embodiments, the first gaseous precursor comprising aluminum comprises a single chlorine ligand and at least two alkyl ligands. In some embodiments, the first gaseous precursor comprising aluminum comprises one hydrogen ligand and at least one alkyl ligand. In some embodiments, the first gaseous precursor comprising aluminum does not comprise nitrogen, silicon or oxygen. In some embodiments, the first gaseous precursor comprising aluminum comprises triethyl aluminum (TEA), trimethyl aluminum (TMA), or tritbutyl aluminum (TTBA) and the second gaseous precursor comprising nitrogen comprises NH ₃ do.

In some embodiments, the second dielectric surface comprises Si-O bonds. In some embodiments, the method includes a thermal atomic layer deposition (ALD) process. In some embodiments, the method does not include a plasma in at least two successive deposition cycles. In some embodiments, the method further comprises exposing the substrate to a pretreatment reagent prior to a first deposition cycle. In some embodiments, the pretreatment reagent comprises a plasma. In some embodiments, exposing the substrate to the pretreatment reagent prior to the first deposition cycle enhances the selectivity by a factor greater than about 2. In some embodiments, the method further comprises exposing the substrate after at least one deposition cycle. In some embodiments, the substrate is exposed to plasma after more than 10 deposition cycles.

In some embodiments, the material comprising aluminum and nitrogen has an etch selectivity for SiO ₂ in dilute HF. In some embodiments, the ratio of aluminum to nitrogen-containing material deposited on the first surface of the same substrate relative to the second dielectric surface of the substrate is greater than about 10: 1, , The thickness of the material comprising aluminum and nitrogen is greater than about 5 nm. In some embodiments, the ratio of aluminum to nitrogen-containing material deposited on the first surface of the same substrate relative to the second dielectric surface of the substrate is greater than about 10: 1, , The thickness of the material comprising aluminum and nitrogen is greater than about 1 nm. In some embodiments, the ratio of aluminum to nitrogen-containing material deposited on a first surface of the same substrate relative to a second dielectric surface of the substrate is greater than about 10: 1, . In some embodiments, the ratio of aluminum to nitrogen-containing material deposited on the first surface of the same substrate relative to the second dielectric surface of the substrate is greater than about 10: 1, . In some embodiments, after about 1 to 25 deposition cycles, a material comprising less than about 0.1 nm of aluminum and nitrogen is deposited on the second dielectric surface of the substrate. In some embodiments, the ratio of the wet etch rate of the deposited aluminum to the nitrogen containing material to the wet etch rate of SiO ₂ is less than about 1: 5.

In some embodiments, the second dielectric surface of the substrate is over a source / drain region, the method comprising: removing a second dielectric surface of the substrate to expose a source / drain region of the substrate; And forming a contact on the region.

In some aspects, methods are provided for selectively depositing AlN on a first surface of the same substrate relative to a second dielectric surface of the substrate. In some embodiments, the method can include one or more cycles comprising alternating sequentially contacting the substrate with gaseous tri-tert-butylaluminum (TTBA) and gaseous NH. In some embodiments, the AlN is deposited with a selectivity in excess of about 50% on the first surface of the same substrate relative to the second dielectric surface of the substrate. In some embodiments, the second dielectric surface comprises Si-O bonds. In some embodiments, the method includes a thermal atomic layer deposition (ALD) process. In some embodiments, the method does not include a plasma in at least two successive deposition cycles. In some embodiments, the method further comprises exposing the substrate to a pretreatment reagent prior to a first deposition cycle. In some embodiments, the pretreatment reagent comprises a plasma. In some implementations, the method may include some or all of the features of any of the other implementations described herein above.

In some aspects, methods are provided for forming an etch stop layer with self-aligned contact formation. In some embodiments, the method includes providing a semiconductor substrate comprising a first surface and a second surface overlying a source / drain region, removing a portion of the first surface of the substrate to form a recess in the substrate Selectively depositing a material comprising aluminum and nitrogen on the first surface relative to the second dielectric surface, removing the second dielectric surface of the substrate to expose a source / drain region of the substrate And forming a contact on the exposed source / drain region of the substrate. In some embodiments, the first surface comprises at least one of copper, titanium nitride, tungsten, and silicon nitride. In some embodiments, the material comprising aluminum and nitrogen is an aluminum nitride film. In some embodiments, the aluminum nitride film comprises oxygen. In some implementations, the method may include some or all of the features of any of the other implementations described herein above.

According to some embodiments, there are provided methods for selectively forming AlN on a first surface relative to a different second surface. In some embodiments, the method comprises: one or more super-cycles comprising selectively depositing AlN on a first surface relative to a different second surface and etching the deposited AlN, wherein the deposition Etched AlN substantially does not remove the entire deposited AlN from the second surface of the substrate and does not remove the entire AlN from the first surface of the substrate.

In some embodiments, the super-cycle further includes repeating the step of selectively depositing AlN and etching the deposited AlN until an AlN thin film of desired thickness is deposited on the first surface. In some embodiments, the super-cycle further comprises exposing the substrate to a pretreatment reactant prior to selectively depositing AlN. In some embodiments, the pretreatment reagent comprises a plasma. In some embodiments, the plasma is generated from a gas comprising H ₂ .

In some embodiments, the step of selectively depositing AlN on a first surface relative to a different second surface comprises contacting the substrate with a first gaseous precursor comprising aluminum and a second gaseous precursor comprising nitrogen, Wherein the AlN has a selectivity greater than about 5% on a first surface of the same substrate relative to a second dielectric surface of the substrate, wherein the at least one selective deposition sub- . In some embodiments, the selective deposition sub-cycle further comprises repeating the selective deposition sub-cycle until a desired thickness of AlN is deposited on the first surface. In some embodiments, the step of selectively depositing AlN comprises repeating the selective deposition sub-cycle until the selective deposition sub-cycle is no longer selective.

In some embodiments, the first gaseous precursor comprising aluminum comprises one of triethylaluminum (TTBA), trimethylaluminum (TMA), or triethylaluminum (TEA). In some embodiments, the second precursor gas phase containing nitrogen comprises NH _3.

In some embodiments, the step of etching the deposited AlN comprises an atomic layer etching (ALE) process, wherein the atomic layer etching process comprises contacting the substrate with a first gaseous halide etch reactant and a second And at least one etch sub-cycle comprising contacting the substrate with a gas-phase etch reactant. In some embodiments, the first gaseous halide etch reactant comprises NF ₃ or NbF ₅ . In some embodiments, the second gas phase etch reactant comprising aluminum comprises trimethyl aluminum (TMA) or triethyl aluminum (TEA). In some embodiments, the etch sub-cycle is performed at a process temperature of about 300 ° C. In some embodiments, the first surface comprises W and the second surface comprises SiO ₂ . In some embodiments, the first surface comprises TiN, and the second surface comprises SiO _2. In some embodiments, the AlN is selectively formed with a selectivity in excess of about 99% on the first surface of the substrate relative to the second surface.

In some embodiments, selectively depositing AlN on a first surface relative to a different second surface comprises performing an optional deposition sub-cycle, wherein the selective deposition sub-cycle is repeated from 1 to about 300 times And etching the deposited AlN comprises an atomic layer etch (ALE) process wherein the etch sub-cycle is repeated from 1 to about 150 times.

In some embodiments, a method for selectively depositing AlN on a first surface of the same substrate relative to a different second surface of the substrate includes a super-cycle, wherein the super-cycle is performed such that AlN is different from A first gaseous precursor comprising aluminum and a second gaseous precursor comprising nitrogen to deposit thereon a selectivity of greater than about 5% on a first surface of the same substrate relative to the second surface, And an atomic layer etch step removing substantially all of the deposited AlN from the second surface of the substrate and substantially removing all of the AlN from the first surface of the substrate, The first gas phase halide etching reactant and the second gas phase etching reactant containing aluminum are alternately and sequentially brought into contact with the substrate It includes an cycle-key sub-atomic layer etch a step.

In some embodiments, the super-cycle is repeated one or more times. In some embodiments, the super-cycle further comprises exposing the substrate to a plasma generated from a gas comprising H ₂ prior to the selective deposition step.

In some embodiments, the first gaseous precursor comprising aluminum comprises TMA, the second gaseous precursor comprising nitrogen comprises NH ₃ , the first gaseous halide etch reactant comprises NF ₃ , Lt; RTI ID = 0.0 > TMA. ≪ / RTI > In some embodiments, the first surface is a conductive surface and the second surface is a dielectric surface.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will be better understood from the detailed description and the accompanying drawings which are meant to illustrate the invention and not to limit the invention,
Figure 1 illustrates a deposition process flow for selectively depositing Al and N containing materials on a first surface of the same substrate relative to a different second surface of the substrate;
Figure 2 shows a deposition process flow for selectively depositing AlN on a first surface of the same substrate relative to a different second surface of the substrate;
Figure 3 illustrates a deposition process flow (including selective deposition sub-cycles and atomic layer etch sub-cycles) for selectively depositing Al and N containing materials on a first surface of the same substrate relative to a different second surface of the substrate. Lt; / RTI >
Figure 4 shows a method flow for forming self-aligned contact structures;
Figure 5 illustrates another method flow for forming self-aligned contact structures;
Figure 6 is a graph of the number of deposited material versus deposition cycles for Al and N containing materials selectively deposited on a first TiN surface relative to a second SiO ₂ surface;
FIG. 7 is a graph of the number of deposited material versus deposition cycles for Al and N containing materials selectively deposited on a first TiN surface relative to SiO ₂ and native oxide second surface;
8 is a graph of deposited material thickness vs. number of deposition cycles for Al and N containing materials selectively deposited on a first TiN surface relative to a second native oxide surface;
9 is a graph of deposited material thickness versus number of deposition cycles for Al and N containing materials selectively deposited on a first TiN or W surface relative to a second SiO ₂ surface;
10A is an AlN scanning electron microscope (SEM) image selectively deposited on tungsten interconnects relative to SiO2;
10B is a partially enlarged view of the SEM image of FIG. 10A.

In some embodiments, it is desirable to selectively deposit a material comprising aluminum (Al) and nitrogen (N), such as aluminum nitride (AlN), on one surface of the same substrate relative to a different second surface of the substrate. For example, selective deposition of Al and N containing materials can be used to form etch stop layers such as a capping layer, a barrier layer, or a contact etch stop layer. For example, the Al and N containing material may be selectively deposited on the first surface of the substrate, preferentially on a different second surface, such as the dielectric surface of the same substrate.

In some embodiments, a substrate is provided that includes a first surface and a different second surface, wherein the Al and N containing material is deposited on the first surface relative to the second surface using an ALD type process comprising a plurality of deposition cycles Wherein each deposition cycle comprises alternately and sequentially bringing the substrate into contact with the first precursor in the gaseous phase and the second precursor in the gaseous phase. In some embodiments, the selectively deposited Al and N containing material is AlN.

In some embodiments, Al and N containing materials, such as AlN, are selectively deposited on the metal surface of the substrate, including both the conductive surface and the dielectric surface. In some embodiments, AlN is selectively deposited on the second dielectric surface, for example, the first conductive surface of the same relative to the SiO ₂ substrate or a low k surface, such as Cu, W or TiN surface of the substrate. In some embodiments, AlN is selectively deposited on the first surface, for example, SiN surface than the second dielectric surface, for example, SiO ₂ or the conductive surface, relative to the low k surface of the substrate. In some embodiments, AlN is selectively deposited on a Cu surface relative to a different second surface. In some embodiments, the AlN is selectively deposited on the W surface relative to a different second surface. In some embodiments, the AlN is selectively deposited on a TiN surface relative to a different second surface. In some embodiments, AlN is selectively deposited on a SiN surface relative to a different second surface.

In some embodiments, methods for selectively depositing aluminum and nitrogen containing materials, such as AlN, include selectively depositing aluminum and nitrogen containing materials on a first surface relative to a different second surface, Wherein the etch process substantially removes all of the deposited aluminum and nitrogen containing material from the second surface of the substrate and substantially completely removes all of the aluminum and nitrogen containing material deposited from the first surface of the substrate Do not remove. In some embodiments, the etch process may be an atomic layer etch process. In some embodiments, the atomic layer etch process may comprise alternating sequentially contacting the substrate with a first gaseous etch reactant comprising aluminum and a second gaseous halide etch reactant.

In some embodiments, the methods for selectively depositing aluminum and nitrogen-containing materials, such as AlN, may comprise a plurality of super-cycles, wherein the plurality of super-cycles comprises a plurality of super- 1-containing material on the first surface and all of the deposited Al and N-containing material are substantially removed from the second surface and at the same time at least a portion of the Al and N-containing material is removed from the first surface And then etching the deposited Al and N containing material to remain on the substrate. This selective deposition super-cycle can be selectively repeated until a desired amount of Al and N containing material is deposited on the first surface of the substrate. In some embodiments, after each selective deposition super-cycle, the aluminum and nitrogen-containing material remains substantially none on the second surface. In some embodiments, after the selective deposition process, the aluminum and nitrogen containing material remains substantially on the second surface.

In some embodiments, the selective deposition super-cycle may further comprise performing a pretreatment process prior to selectively depositing the Al and N containing material. In some embodiments, the pretreatment step may include exposing the substrate to a pretreatment reaction: In some embodiments, the pretreatment reaction product can contain a plasma generated from a gas containing a plasma, for example H ₂ have.

ALD type  fair

The ALD type process is based on controlled self-limiting surface reactions of precursor chemicals. The vapor phase reaction is avoided by bringing the substrate into contact with the precursor alternately and continuously. The gaseous reactants are separated from one another on the substrate surface, for example, by removing excess reactants and / or reactant by-products from the reaction chamber between reactant pulses. In some embodiments, one or more substrate surfaces are alternately and sequentially in contact with two or more gaseous precursors or reactants. Contacting the substrate surface with the gaseous reactant means that the reactant vapor is in contact with the substrate surface for a limited period of time. That is, the substrate surface is exposed to each gas phase reactant for a limited period of time.

Briefly, a substrate comprising at least a first surface and a different second surface is heated to a suitable deposition temperature at a generally lower pressure. The deposition temperature is generally below the thermal decomposition temperature of the reactants, but is maintained at a level high enough to avoid condensation of the reactants and provide activation energy for the desired surface reaction. Of course, the appropriate temperature range for any given ALD reaction will vary depending on the surface end and the reactive species involved. Here, the temperature varies depending on the precursor in use and is preferably about 500 캜 or lower, preferably about 250 캜 to about 500 캜, more preferably about 275 캜 to about 450 캜, and still more preferably about 300 캜 To about 425 캜, and most preferably from about 325 캜 to about 400 캜.

The substrate surface is in contact with the first reactant in the gaseous phase. In some embodiments, a pulse of the first reactant in the gaseous phase is provided in a reaction space containing the substrate. In some embodiments, the substrate is transferred to a reaction space containing the first reactant in the gaseous phase. It is desirable to select conditions such that about one or less of the monolayers of the first reactant are adsorbed on the substrate surface in a self-limiting manner. The appropriate contact time can be readily determined by one skilled in the art based on the particular circumstances. If excess first reactants and reaction by-products are present, they are removed from the substrate surface, for example, by purging with an inert gas or by removing the substrate from the presence of the first reactant.

Purging means that the gaseous precursor and / or gaseous by-products are removed, for example, by evacuating the chamber with a vacuum pump and / or by replacing the gas inside the reactor with an inert gas such as argon or nitrogen. Typical purging times are from about 0.05 to 20 seconds, more preferably from about 1 to 10, and even more preferably from about 1 to 2 seconds. However, other purge times may be used if necessary, for example, if highly conformal step coverage is desired, e.g., for very high aspect ratio structures or other structures with complex surface morphologies.

The substrate surface is in contact with the gaseous second gaseous reactant. In some embodiments, a pulse of the second gaseous reactant is provided in a reaction space comprising the substrate. In some embodiments, the substrate is transferred to a reaction space comprising a gaseous second reactant. If there are excess secondary reactants and gas byproducts of the surface reaction, they are removed from the substrate surface. The contacting and removing steps are repeated until a thin film of desired thickness is selectively formed on the surface of the substrate, each cycle leaving only about one molecular monolayer. Additional steps may be included to form more complex materials, such as ternary materials, including alternating successive contact of the substrate surface with other reactants.

As noted above, each step of each cycle is preferably self-limiting. Excess reactant precursors may be provided at each step to saturate the delicate structural surface. Surface saturation ensures good step coverage because it ensures reactant occupancy of all available reaction sites (e.g., physical size or application of "steric hindrance" reactants). Typically, less than one layer of molecular material is deposited using each cycle, but in some embodiments, one or more molecular layers are deposited during the cycle.

The step of removing excess reactant may include discharging a portion of the contents of the reaction space and / or purging the reaction space with helium, nitrogen or other inert gas. In some embodiments, purging may include blocking the flow of the reactant gas while continuously flowing an inert carrier gas into the reaction space.

The substrate may include various types of materials. BACKGROUND OF THE INVENTION [0002] When manufacturing integrated circuits, substrates generally include many thin films with varying chemical and physical properties. For example and without limitation, the substrate may comprise a dielectric layer and a metal layer. In some embodiments, the substrate may comprise a metal carbide. In some embodiments, the substrate may comprise a conductive oxide.

Preferably, the substrate has a first surface comprising a conductive surface, such as a metal or metal surface. In some embodiments, the first surface comprises a metal nitride. In some embodiments, the first surface may comprise one or more transition metals. The transition metal may be selected from the group of Ti, V, Cr, Mn, Nb, Mo, Ru, Rh, Pd, Ag, Au, Hf, Ta, W, Re, Os, Ir and Pt. In another embodiment, the transition metal is selected from the group of Fe, Co, Ni. In some embodiments, the first surface preferably comprises copper. In some embodiments, the first surface comprises a noble metal. The noble metals may be selected from the group of: Au, Pt, Ir, Pd, Os, Ag, Re, Rh, and Ru. In some preferred embodiments, the first surface comprises at least one of Cu, W, TiN, TaN or SiN.

In some embodiments, the first surface may comprise more than one material, such as TiN and SiN.

In some embodiments, the first surface comprises a metal suicide, such as a transition metal suicide. In some embodiments, the first surface comprises a metal film comprising a transition metal, such as a transition metal carbide or a carbon containing transition metal material. In some embodiments, the first surface may comprise Al. In some embodiments, the first surface may comprise metals or an alloy of metallic materials.

The second surface is preferably a dielectric surface, such as SiO ₂ , GeO ₂ , or a low k surface. In some embodiments, the dielectric comprises SiO ₂ . In some embodiments, the dielectric is a porous material. In some embodiments, the porous dielectric includes pores connected to one another, while in other embodiments the pores are not connected to each other. In some embodiments, the dielectric comprises a low k material that is defined as an insulator having a dielectric constant value less than about 4.0. In some embodiments, the dielectric constant value of the low k material is less than about 3.5, less than about 3.0, less than about 2.5, and less than about 2.3. In some embodiments, the second surface comprises Si-O bonds. In some embodiments, the second surface is deactivated, for example, by plasma treatment. In some embodiments, the second surface is a non-conductive surface. In some embodiments, the second surface has a resistivity greater than about 1 ohm-m. In some embodiments, the second surface comprises Si-O bonds and has a resistivity of less than about 1 ohm-m. The term dielectric is used herein for the sake of simplicity in distinguishing it from other first surfaces, i.e. metal or metal surface. Unless otherwise specified with respect to a particular embodiment, the term dielectric in the context of the present application can be understood to denote all surfaces with very high resistivity.

When the precursors used in the ALD type process are in the gaseous phase before contacting the substrate surface, these precursors may be solid, liquid or gaseous materials under standard conditions (room temperature and atmospheric pressure). Contacting the substrate surface with the vaporized precursor means that the precursor vapor is in contact with the substrate surface for a limited period of time. Typically, the contact time is about 0.05 to 10 seconds. However, depending on the substrate type and its surface area, the contact time can be much longer than 10 seconds. The contact time may be in minutes depending on the case. The optimal contact time can be determined by one skilled in the art based on the particular circumstances.

The mass flow rate of the precursor can also be determined by one skilled in the art. In some embodiments, the flow rate of the metal precursor is preferably about 1 to 1000 sccm, more preferably about 100 to 500 sccm, without limitation.

The pressure in the reaction chamber is typically about 0.01 to about 20 mbar, more preferably about 1 to about 10 mbar. However, as may be determined by those skilled in the art under given circumstances, in some cases the pressure may be higher or lower than this range.

Prior to beginning deposition of the film, the substrate is typically heated to an appropriate growth temperature. Growth temperature depends on the type of thin film formed, the physical properties of the precursor, and so on. The growth temperature is discussed in more detail below with reference to each type of thin film formed. The growth temperature may be less than the crystallization temperature for the deposited material so that an amorphous thin film can be formed, or the growth temperature may exceed the crystallization temperature so that a crystalline thin film is formed. The preferred deposition temperature may vary depending on the composition of the substrate, including without limitation, the reactant precursor, the pressure, the flow rate, the arrangement of the reactor, the crystallization temperature of the deposited film, and the nature of the material to be deposited thereon. Certain growth temperatures may be selected by those skilled in the art.

Reactors that can be used to grow thin films can be used for deposition. Such a reactor includes an ALD reactor as well as a CVD reactor equipped with suitable equipment and means for providing precursors. According to some embodiments, a showerhead reactor may be used.

Examples of suitable reactors that can be used include commercially available equipment used in, for example, ASM America Inc. (Phoenix, Arizona) and ASM Europe BV (Almere, The Netherlands) in F-120 ^® reactor, F-450 ^® reactor, Pulsar ^® Reactors (e.g., Pulsar ^® 2000 and Pulsar ^® 3000), EmerALD ^® reactor and Advance ^® 400 series. Commercially available reactors include products from ASM Japan KK (Japan, Tokyo) with trade names of Eagle ^® XP and XP8.

In some embodiments, a batch reactor may be used. Suitable batch reactors include, but are not limited to, reactors commercially available from ASM Europe BV (ALMER, The Netherlands) under the trade names ALDA400 ^TM and A412 ^TM . In some embodiments, a vertical batch reactor in which a boat rotates during processing, such as A412 ?, is used. As such, in some embodiments, the wafer rotates during processing. In some embodiments in which a batch reactor is used, the wafer to wafer uniformity is less than 3% (1 sigma), less than 2%, less than 1%, or even less than 0.5%.

The growth process may optionally be performed in a reactor or reaction space connected to the cluster tool. In the cluster tool, since each reaction space is dedicated to one type of process, the temperature of the reaction space within each module can be kept constant, which means that compared to a reactor heated to process temperature before the substrate is each run, .

The stand-alone reactor may be equipped with a load-lock. In this case, it is not necessary to cool the reaction space between each run.

Preferably, to form the Al and N containing material, each ALD cycle comprises at least two distinct phases. Removing excess first precursor and reaction byproducts from the substrate surface after contacting the substrate with the first precursor may be considered as a step and may be considered as a step and may be a first step, a first precursor step, an Al step, an Al precursor step, , ≪ / RTI > the first AL precursor stage. In the case of a deposition cycle, in the first step, the substrate is contacted with a first precursor containing Al forming only one monolayer on the substrate. In a second step, the substrate is contacted with a second precursor comprising nitrogen and can convert the adsorbed first precursor into Al and N containing materials. Removing excess second precursor and reaction byproducts from the substrate surface after contacting the substrate with the second precursor may be considered as a step and may be considered as a step and may be a second step, a second precursor step, a nitridation step, an N step, an N precursor step, 1 N step, and / or a first N precursor step. At least one precursor is N _2, Ar, or < RTI ID = 0.0 > He. ≪ / RTI > Additional steps can be added and steps can be eliminated when trying to control the composition of the final film.

Referring to Figure 1 and in accordance with a preferred embodiment, the Al and N containing material is deposited on the first surface of a substrate comprising a first surface and a different second surface by an ALD type deposition process 100 comprising at least one cycle The at least one cycle comprising the steps of:

Contacting the substrate with a first gaseous precursor comprising Al in step 120;

Removing excess first precursor and reaction by-products from the substrate if excess first precursor and reaction by-product are present in step 130;

Contacting the substrate with a second gaseous precursor comprising nitrogen in step 140;

Removing an excess of the second precursor and any gaseous byproduct from the substrate in step 150; And

Optionally repeating the contacting and removing steps until a desired thickness of Al and N containing material is formed in step 160. [

In some embodiments, a pretreatment process may be performed on one or more surfaces of the substrate prior to beginning the deposition process 100. In some embodiments, the pretreatment process may improve the selectivity of the selective deposition process 100. In some embodiments, the pretreatment process prior to starting the deposition process 100 may improve the deposition of Al and N containing material on one surface relative to one or more different surfaces. In some embodiments, the pretreatment process prior to starting the deposition process 100 can inhibit the deposition of Al and N containing materials on one surface relative to one or more different surfaces. In FIG. 1, this is represented by step 110, where the substrate may be exposed to a pretreatment reagent, such as a plasma, prior to deposition of the Al and N containing material.

In some embodiments, the pretreatment process may include exposing the substrate to a pretreatment reagent. In some embodiments, the pretreatment reagent may comprise oxygen. In some embodiments, the pretreatment reagent comprises an oxygen radical, an oxygen atom, an oxygen plasma, or a combination thereof. In some embodiments, the pretreatment reagent may comprise nitrogen. In some embodiments, the pretreatment reagent comprises a nitrogen radical comprising nitrogen, atomic nitrogen, a nitrogen plasma, or a combination thereof. In some embodiments, the pretreatment reagent may comprise hydrogen. In some embodiments, the pretreatment reagent comprises a hydrogen radical, a hydrogen atom, a hydrogen plasma, or a combination thereof.

In some embodiments, when the substrate is subjected to a pretreatment process in which it is exposed to a pretreatment reagent comprising an oxygen plasma, the O ₂ may be, for example, from about 1 to about 2000 sccm, more preferably from about 5 to about 1000 sccm, May be provided at about 50 to about 500 sccm. In some embodiments, O ₂ may be provided at about 300 sccm. In some embodiments, when a substrate is subjected to a pretreatment process that is exposed to a pretreatment reagent comprising a nitrogen plasma, N ₂ may be, for example, from about 1 to about 5000 sccm, more preferably from about 5 to about 2000 sccm, May be provided at about 50 to about 500 sccm. In some embodiments, N ₂ may be provided at about 300 sccm. In some embodiments, when a substrate is subjected to a pretreatment process that is exposed to a pretreatment reagent comprising a hydrogen plasma, H ₂ may be, for example, from about 1 to about 2000 sccm, more preferably from about 5 to about 1000 sccm, May be provided at about 10 to about 100 sccm. In some embodiments, H ₂ may be provided at about 50 sccm. Similar conditions may be used for other types of plasma.

In some embodiments, the pretreatment process may include exposing the substrate to a pretreatment reaction at a predetermined temperature. In some embodiments, the pretreatment temperature may be greater than about 20 < 0 > C. In some embodiments, the pretreatment temperature may be from about 20 ° C to about 500 ° C, more preferably from about 50 ° C to about 450 ° C, and more preferably from about 150 ° C to about 400 ° C. In some embodiments, the pretreatment temperature may be approximately the same as the deposition temperature. In some embodiments, the pretreatment temperature may be different from the deposition temperature. In some embodiments, the plasma can be generated at an output of less than about 2500 watts, such as between about 1 and about 1000 watts, between about 1 and about 500 watts, or between about 1 and about 200 watts. In some embodiments, the plasma may be generated at an output of 50 W. In some embodiments, the plasma may be generated at an output of 100 W.

In some embodiments, the plasma is provided for less than about 200 seconds, less than about 180 seconds, less than about 60 seconds, less than about 30 seconds, less than about 10 seconds, or less than about 3 seconds.

In some embodiments, a plasma is formed in the reactor. In some embodiments, the plasma may be formed on the top of the substrate or in situ in proximity to the substrate. In another embodiment, the plasma is formed in the remote plasma generator upstream of the reaction chamber, and the plasma products are directed to the reaction chamber and contact the substrate. As will be appreciated by those skilled in the art, in the case of remote plasma, the path to the substrate can be optimized to maximize electronically neutral species and minimize ion survival before reaching the substrate.

In some embodiments, the treated substrate is not exposed to the ambient environment prior to the start of the selective deposition process after the pretreatment process. In some embodiments, the treated substrate is not exposed to air after the pretreatment process and prior to the start of the selective deposition process.

In some embodiments, the pretreatment process can be used to improve the selectivity of the subsequent selective deposition process. In some embodiments, the pretreatment process may enhance selective deposition of Al and N containing materials on the first surface relative to the second, different surface. In some embodiments, the pretreatment process may improve the selectivity of subsequent selective deposition processes by a factor greater than about 2, greater than about 5, or greater than about 10.

In some embodiments, the pretreatment process may be performed in the same reaction chamber or reactor as the subsequent deposition process 100. In some embodiments, the pretreatment process may be performed in a reaction chamber or reactor that is different from the subsequent deposition process 100.

Referring back to Figure 1, in step 120 the substrate contacts a first precursor comprising Al. In some embodiments, the first precursor is directed into the reaction chamber in the form of a gaseous pulse to contact the substrate surface. It is preferred that the conditions be selected such that only one monolayer of the precursor is adsorbed on the substrate surface in a self-limiting manner. However, in some embodiments, conditions may be selected so that only one single layer of the precursor can be formed.

The first precursor pulse is preferably supplied in gaseous form. If the paper exhibits sufficient vapor pressure under process conditions to transport the species to the workpiece at a concentration sufficient to saturate the exposed surface, the first precursor gas is considered " volatile " for purposes of this disclosure.

In some embodiments, the first precursor is reacted for about 0.01 second to about 60 seconds, for about 0.02 second to about 30 seconds, for about 0.025 second to about 20 seconds, for about 0.05 second to about 5.0 seconds, 2.0 seconds, or from about 0.1 second to about 1.0 second.

When the first precursor used in the ALD-type process is guided to the reaction chamber and is present in the gas phase before contacting the substrate surface, the first precursor may be a solid, liquid or gaseous material under standard conditions (room temperature and atmospheric pressure).

If the first precursor and reaction byproducts are present in step 130, they are removed from the substrate surface by purging with a pulse of an inert gas such as, for example, nitrogen or argon. Purging the reaction chamber means removing the gaseous precursor and / or gaseous byproducts from the reaction chamber, for example by evacuating the chamber with a vacuum pump and / or replacing the gas inside the reactor with an inert gas such as argon or nitrogen. A typical purging time is about 0.05 to 20 seconds, more preferably about 1 to 10 seconds, and even more preferably about 1 to 2 seconds. However, if necessary, other purging times may be used, for example when it is necessary to deposit a layer on a very high aspect ratio structure or other structure with complex surface morphology. The appropriate purging time can be readily determined by one skilled in the art based on the particular circumstances.

However, in other embodiments, when there is an excess of first precursor and reaction byproduct, removal of excess first precursor and reaction by-product may include moving the substrate such that the first precursor is no longer in contact with the substrate have. In some embodiments, no precursor may be removed from various portions of the chamber. In some embodiments, the substrate is transferred from another portion of the chamber containing the first precursor to another portion of the chamber containing the second precursor or containing no precursor. In some embodiments, the substrate is transferred from the first reaction chamber to a different second reaction chamber.

In step 140, the substrate is contacted with a gaseous precursor containing N. In some embodiments, the second precursor is pulsed into a chamber that reacts with a first precursor bound to a first surface of the substrate. Generally, in this reaction, a material is formed on the substrate to reach about one single layer containing Al and N. [ However, in some embodiments, a material is formed on the substrate that exceeds one molecular layer containing Al and N.

In some embodiments, the second precursor may comprise a nitrogen plasma or a nitrogen radical. In this embodiment, nitrogen may be activated in the reaction chamber or upstream of the reaction chamber. Where a plasma is required, after the substrate is exposed to the nitrogen plasma for a desired period of time, the plasma generator may be turned off and the flow of nitrogen precursor itself may be activated to remove excess nitrogen plasma and unreacted by- The flow of the second precursor may include a kind of purge gas.

Those skilled in the art will recognize that any number of suitable second precursors may be used, but suitable second precursors preferably include nitrogen containing compounds that react with the ligands of the first precursor deposited before or after. Thus, selection of a suitable second precursor may depend on the nature of the ligands in the first precursor and the particular first precursor used.

In some embodiments, the second precursor is reacted for about 0.01 second to about 60 seconds, for about 0.02 second to about 30 seconds, for about 0.025 second to about 20 seconds, for about 0.05 second to about 5.0 seconds, 2.0 seconds, or from about 0.1 second to about 1.0 second. However, depending on the reactor type, substrate type and surface area, the second precursor contact time can be much longer than 10 seconds. In some embodiments, the contact time may be in minutes. The optimal contact time can be readily determined by one skilled in the art based on the particular circumstances.

The concentration of the second precursor in the reaction chamber may be from about 0.01 vol% to about 99.0 vol%. In addition, the second precursor can flow from the reaction chamber through the reaction chamber at a rate of about 1 standard cm ³ / min and about 4000 standard cm ³ / min.

At step 150, if there is an excess of second precursor and a gaseous byproduct of the surface reaction, these excess second precursor and gaseous byproducts are removed from the substrate, as described above for step 130. In some embodiments, excess precursor and reaction by-products are preferably removed with the aid of an inert gas.

The contacting and removing step can be selectively repeated at step 160 until each of the Al and N containing material of desired thickness is formed on the surface of the substrate, and each cycle leaves only one molecular monolayer. In some cases, it may be desirable to at least partially decompose at least one of the various precursors. As such, in some embodiments, conditions can be selected such that only one molecular layer of Al and N containing material is formed on the substrate in each deposition cycle.

The ALD process of the presently disclosed Al and N containing materials may comprise one or more cycles. Some embodiments include repetitions of at least about 5 cycles, at least about 10 cycles, or at least about 50 cycles. In some embodiments, less than 100 cycles are performed to form a thin film of desired thickness.

In some embodiments, the substrate surface and / or the Al and N containing material may optionally undergo a plasma treatment process. In Figure 1, this is indicated by step 170. In some embodiments, the plasma treatment process may be performed after more than one deposition cycle is performed. In some embodiments, the plasma treatment process may be performed before the deposited Al and N containing material film is either continuous or closed. In some embodiments, the plasma treatment process can be performed each time about 10 deposition cycles pass, about 20 deposition cycles, or about 50 deposition cycles. In some embodiments, at least two successive deposition cycles are performed without a plasma treatment process. In some embodiments, at least five or ten deposition cycles are performed without a plasma treatment process. In some embodiments, the plasma treatment process may be performed before any deposition is performed, i. E., Before any deposition cycle is performed.

In some embodiments, the plasma treatment process may be performed in the same reaction chamber or reactor as the deposition process 100. [ In some embodiments, the plasma treatment process may be performed in a reaction chamber or reactor that is different from the deposition process 100.

In some embodiments, a plasma is formed in the reactor. In some embodiments, the plasma may be formed on the top of the substrate or in situ in proximity to the substrate. In another embodiment, the plasma is formed in the remote plasma generator upstream of the reaction chamber, and the plasma products are directed to the reaction chamber and contact the substrate. As will be appreciated by those skilled in the art, in the case of remote plasma, the path to the substrate can be optimized to maximize electronically neutral species and minimize ion survival before reaching the substrate.

In some embodiments, the Al and N containing material may be deposited using a plurality of deposition cycles and the plasma treatment may be performed, for example, before deposition, every deposition cycle, at predetermined intervals during deposition, N-containing material may be applied more than once, including after deposition.

In some embodiments, the plasma processing process includes exposing the substrate directly to a plasma. In some embodiments, the plasma processing process includes exposing the substrate to a remote plasma. In some embodiments, the plasma treatment process includes exposing the substrate to an excited species or atomic species produced in a plasma discharge, but does not include a substantial amount of ions if they are present. In some embodiments, the plasma may comprise oxygen. In some embodiments, the plasma may comprise nitrogen. Although referred to as a plasma treatment process, in some embodiments, a reactive oxygen species that does not include a plasma, such as ozone, may be used. In some embodiments, the plasma may comprise hydrogen.

In some embodiments, the use of a pretreatment process or a plasma treatment process in which a substrate is exposed to a reactant includes an oxygen plasma. O ₂ may be provided as a source gas, for example, from about 1 to about 2000 sccm, more preferably from about 5 to about 1000 sccm, and most preferably from about 50 to about 500 sccm. In some embodiments, O ₂ may be provided at about 300 sccm.

In some embodiments, the use of a pretreatment process or a plasma treatment process in which a substrate is exposed to a reactant includes a nitrogen plasma. N ₂ may be provided as a source gas, for example, from about 1 to about 5000 sccm, more preferably from about 5 to about 2000 sccm, and most preferably from about 50 to about 500 sccm. In some embodiments, N ₂ may be provided at about 300 sccm.

In some embodiments, the use of a pretreatment process or a plasma treatment process in which a substrate is exposed to a reactant includes a hydrogen plasma. In some embodiments, H ₂ may be provided as a source gas, for example, from about 1 to about 2000 sccm, more preferably from about 5 to about 1000 sccm, and most preferably from about 10 to about 100 sccm. In some embodiments, H ₂ may be provided at about 50 sccm. Similar conditions may be used for other types of plasma.

In some embodiments, the plasma treatment process may comprise exposing the substrate to the reactants at a processing temperature. In some embodiments, the treatment temperature may be greater than about 20 ° C. In some embodiments, the treatment temperature may be from about 20 캜 to about 500 캜, more preferably from about 50 캜 to about 450 캜, and still more preferably from about 150 캜 to about 400 캜. In some embodiments, the treatment temperature may be approximately the same as the deposition temperature and / or the pretreatment temperature. In some embodiments, the treatment temperature may be different from the deposition temperature and / or the pretreatment temperature.

In some embodiments, the plasma can be generated at an output of less than about 2500 watts, such as from about 1 to about 1000 watts, from about 1 to about 500 watts, or from about 1 to about 200 watts or less. In some embodiments, the plasma may be generated at an output of 50 W. In some embodiments, the plasma may be generated at an output of 100 W.

In some embodiments, the plasma is provided for less than about 200 seconds, less than about 180 seconds, less than about 60 seconds, less than about 30 seconds, less than about 10 seconds, or less than about 3 seconds.

In some embodiments, the plasma treatment process 170 may be substantially the same as the pretreatment process 110.

The illustrated deposition cycle of the Al and N containing material begins with bringing the surface of the substrate into contact with a first gaseous precursor comprising Al, however, in other embodiments, the deposition cycle is performed by exposing the surface of the substrate to a second gaseous precursor ≪ / RTI > Those skilled in the art will appreciate that contacting the substrate with the first gaseous precursor containing Al and the second gaseous precursor containing nitrogen may be interchanged in the deposition cycle.

In some embodiments, the substrate is moved such that the different reactants sequentially contact alternately with the surface of the substrate in the desired order for the desired time. In some implementations, the removal steps 130 and 150 are not performed. In some embodiments, no reactants may be removed from various portions of the chamber. In some embodiments, the substrate is moved from one portion of the chamber containing the first precursor to another portion of the chamber containing the second reactant. In some embodiments, the substrate is transferred from the first reaction chamber to a different second reaction chamber.

Those skilled in the art will be able to determine the optimum reactant evaporation temperature based on the properties of the selected precursors. The skilled artisan can determine the optimum reactant contact time through routine experimentation based on the properties of the selected precursor and the desired properties of the deposited Al and N containing material.

The growth rate of Al and N containing materials will vary depending on the reaction conditions. As described below, in the initial experiments, the growth rate varies between about 0.01 A / cycle and 2.0 A / cycle. In some embodiments, the growth rate may be from about 0.01 A / cycle to about 3.0 A / cycle, preferably from about 0.1 A / cycle to about 2.5 A / cycle, more preferably from 0.3 A / cycle to about 2.0 A / cycle have.

In some embodiments, the deposited Al and N containing material comprises a thin film. In some embodiments, the deposited Al and N containing material comprises AlN, and the Al and N containing material deposited in some embodiments is AlN. In some embodiments, Al and N containing materials consisting essentially of Al and N are formed. In some embodiments, additional reactants, such as oxygen, may be used to incorporate or contribute to the film to form the aluminum oxynitride film. In some embodiments where non-metallic components other than nitrogen are required, the ALD method for forming Al and N containing materials may include steps other than the initial Al and N steps. For example, if a metal aluminum oxynitride film is required, the method may include an oxidation step. In the oxidation step, an oxygen or oxygen containing precursor is provided to the reaction chamber to contact the substrate surface. The oxygen step may be part of one or more deposition cycles. In some embodiments, a second metal step may be provided in one or more deposition cycles. The oxygen step, or other desired step, may be performed after the Al step or N step, but in some situations, in some embodiments, excess oxygen (or other reactant) and any reaction by- . In some embodiments, additional steps such as oxygen or additional metal steps may be provided intermittently after the final deposition cycle or during the deposition process.

In some embodiments, the deposition of the Al and N containing material on the first surface of the substrate relative to the second surface of the substrate is at least about 90% selective, at least about 95% selective, at least about 96%, 97%, 98% More than 99% selective. In some embodiments, deposition of the Al and N containing material occurs only on the first surface and not on the second surface. In some embodiments, the deposition on the first surface of the substrate relative to the second surface of the substrate is at least about 80% selective, which may be sufficiently selective in some special applications. In some embodiments, the deposition on the first surface of the substrate relative to the second surface of the substrate is at least 50% selective, which may be sufficiently selective in some special applications. In some embodiments, the deposition on the first surface of the substrate relative to the second surface of the substrate comprises at least about 1%, at least about 2.5%, at least about 5%, at least about 10%, at least about 15%, at least about 20% At least about 25%, at least about 30%, or at least about 40%, all of which may be sufficiently selective for some particular applications.

In some embodiments, the ratio of Al and N containing material deposited on the first surface of the substrate relative to the second surface of the substrate may be at least about 10: 1, at least about 20: 1, or at least about 40: 1. In some embodiments, the thickness of the Al and N containing material deposited on the first surface is greater than about 5 nm, the thickness of the Al and N containing material deposited on the first surface of the substrate relative to the second surface of the substrate The ratio may be at least about 10: 1, at least about 20: 1, or at least about 40: 1. In some embodiments, the thickness of the Al and N containing material deposited on the first surface is greater than about 2.5 nm, the thickness of the Al and N containing material deposited on the first surface of the substrate relative to the second surface of the substrate The ratio may be at least about 10: 1, at least about 20: 1, or at least about 40: 1. In some embodiments, the thickness of the Al and N containing material deposited on the first surface is greater than about 1 nm, the thickness of the Al and N containing material deposited on the first surface of the substrate relative to the second surface of the substrate The ratio may be at least about 10: 1, at least about 20: 1, or at least about 40: 1.

In some embodiments, when the Al and N containing material deposition process comprises about 0 to about 25 deposition cycles, about 0 to about 50 deposition cycles, about 0 to about 100 deposition cycles, or about 0 to about 150 deposition cycles, The ratio of Al and N containing material deposited on the first surface of the substrate relative to the second surface of the substrate may be at least about 10: 1, at least about 20: 1, or at least about 40: 1. In some embodiments, when the Al and N containing material deposition process comprises about 0 to about 25 deposition cycles, about 0 to about 50 deposition cycles, about 0 to about 100 deposition cycles, or about 0 to about 150 deposition cycles, An Al and N containing material of less than about 0.1 nm is deposited on the second surface of the substrate.

In some embodiments, the Al and N containing material has an etch selectivity to SiO ₂ , i.e., the Al and N containing material has an etch rate that is less than the etch rate of SiO ₂ , for example, in dilute HF. In some embodiments, the Al and N containing material has a wet etch rate (WER) less than 1/5 of the thermal oxide removal rate of about 2 to 3 nm per minute using diluted HF (0.5%). In some embodiments, the wet etch rate of the Al and N containing material relative to the wet etch rate of the thermally oxidized silicon (SiO ₂ , TOX) is less than about 0.2 at 0.5% dHF. In some embodiments, the wet etch rate of the Al and N containing material relative to the wet etch rate of TOX is less than about 0.1 at 0.5% dHF. In some embodiments, the wet etch rate of the Al and N containing material relative to the wet etch rate of TOX is less than about 0.05 at 0.5% dHF.

Referring to Figure 2, in some embodiments, a substrate is provided that includes a first surface and a second dielectric surface, and the AlN is deposited on the first surface of the substrate by a periodic deposition method 200 comprising at least one cycle , Said one cycle comprising: < RTI ID = 0.0 >

Contacting the substrate with vapor trimethyl aluminum (TMA) in step 220;

In step 230, if excess TMA and reaction byproducts are present, removing excess TMA and reaction byproducts from the surface;

Contacting the substrate with gaseous NH ₃ in step 240;

In step 250, excess NH ₃ and any reaction byproducts are removed from the surface; And

In step 260, selectively repeating the contacting and removing steps until an AlN thin film of desired thickness is formed.

The AlN deposition cycle is illustrated, but begins by contacting the substrate with TMA, in other embodiments, the deposition cycle can be initiated by contacting the substrate with NH _3. Those skilled in the art will appreciate that the step of contacting the substrate surface with TMA and NH ₃ may be interchanged in the deposition cycle.

In some embodiments, a pretreatment process may be performed on one or more surfaces of the substrate prior to starting the deposition process. In some embodiments, the pretreatment process may improve the selectivity of the selective deposition process 200. In some embodiments, the pretreatment process can improve the deposition of AlN on one surface relative to one or more different surfaces prior to starting the deposition process. In some embodiments, the pretreatment process can inhibit the deposition of AlN on one surface relative to one or more different surfaces prior to starting the deposition process. In FIG. 2, this is represented by step 210, where the substrate may be exposed to a pretreatment reagent, such as a plasma, prior to deposition of the Al and N containing material.

In some embodiments, the substrate surface and / or the AlN thin film may optionally undergo a plasma treatment process. In FIG. 2, this is indicated by step 270. In some embodiments, this plasma treatment process is substantially the same as the plasma treatment process 170 described above with respect to FIG. In some embodiments, the plasma treatment process 270 may be substantially the same as the pretreatment process 210. In some embodiments, the plasma treatment process may be performed after more than one deposition cycle is performed. In some embodiments, the plasma treatment process may be performed before the deposited AlN film is continuous or closed. In some embodiments, the plasma treatment process may be performed after about 10 deposition cycles, after about 20 deposition cycles, or after about 50 deposition cycles. In some embodiments, the plasma treatment process may be performed in the same reaction chamber or reactor as the deposition process 200. [ In some embodiments, the plasma treatment process may be performed in a reaction chamber or reactor that is different from the deposition process 200.

In some embodiments, there is provided a substrate comprising a first surface and a second dielectric surface, wherein the Al and N containing material is selectively and selectively deposited on the first surface of the substrate using a periodic deposition process comprising at least one deposition cycle Wherein the at least one deposition cycle comprises alternately and sequentially contacting the substrate with a gaseous first precursor and a gaseous second precursor. In some embodiments, the first precursor may comprise Al and the second precursor may comprise N. In some embodiments, In some embodiments, the first precursor may comprise tri-butyl-aluminum and the second precursor may comprise NH ₃ .

In some embodiments, there is provided a substrate comprising a first surface and a second dielectric surface, wherein the AlN is selectively deposited on the first surface of the substrate using a periodic deposition process comprising at least one deposition cycle, Wherein the at least one deposition cycle comprises alternately and sequentially contacting the substrate with a gaseous first precursor and a gaseous second precursor. In some embodiments, the first precursor may comprise Al and the second precursor may comprise N. In some embodiments, In some embodiments, the first precursor may comprise tri-butyl-aluminum and the second precursor may comprise NH ₃ .

In some embodiments, a substrate is provided, and the AlN is deposited on a portion of the substrate using a periodic deposition process that includes at least one deposition cycle, wherein the at least one deposition cycle comprises a first precursor of gaseous phase Sequentially contacting the second precursor and the substrate alternately, and the second precursor may comprise NH ₃ .

In some embodiments, the substrate may undergo a pretreatment process prior to deposition. In some embodiments, the pretreatment process may improve the selectivity of the selective deposition process. In some embodiments, the pretreatment process can improve the deposition of AlN on one surface relative to one or more different surfaces prior to starting the deposition process. In some embodiments, the pretreatment process can inhibit the deposition of AlN on one surface relative to one or more different surfaces prior to starting the deposition process. In some embodiments, the pretreatment process may include exposing the substrate to a predetermined reactant, such as a plasma, prior to the deposition of AlN.

In some embodiments, the substrate surface and / or the AlN thin film may optionally undergo a plasma treatment process. In some embodiments, this plasma treatment process is substantially the same as the plasma treatment processes 170 and 270 described above with respect to FIGS. 1 and 2. In some embodiments, the plasma treatment process may be substantially the same as the pretreatment process. In some embodiments, the plasma treatment process may be performed after more than one deposition cycle is performed. In some embodiments, the plasma treatment process may be performed before the deposited AlN film is continuous or closed. In some embodiments, the plasma treatment process may be performed after less than about 10 deposition cycles, less than about 20 deposition cycles, or less than about 50 deposition cycles. In some embodiments, the plasma treatment process may be performed in the same reaction chamber or reactor as the deposition process. In some embodiments, the plasma treatment process may be performed in a reaction chamber or reactor that is different from the deposition process.

Referring to Figure 3 and in accordance with some embodiments, the Al and N containing material is processed by a process 300 that includes at least one super-cycle 301, a different substrate of a substrate comprising a first surface and a different second surface 2 surface, wherein the at least one super-cycle comprises the steps of:

Depositing Al and N containing material on a first surface of the substrate relative to a different second surface in step 320;

Etching all of the Al and N containing material deposited in step 330 such that not all of the deposited Al and N containing material is substantially removed from the second surface and all of the deposited Al and N containing material is not removed from the first surface;

Selectively repeating a selective deposition and etch step until the desired thickness of Al and N containing material is formed on the first surface of the substrate relative to the second surface in step 340.

In some embodiments, at the start of the super-cycle 301, one or more surfaces of the substrate may undergo a pretreatment process. In some embodiments, the pretreatment process can improve the selectivity of the optional deposition process step 320. [ In some embodiments, the pretreatment process prior to optional deposition step 320 may improve the deposition of Al and N containing material on one surface relative to one or more different surfaces. In some embodiments, the pretreatment process prior to optional deposition step 320 may inhibit the deposition of Al and N containing material on one surface relative to one or more different surfaces. In FIG. 3, this is represented by step 310 of the super-cycle 301 where the substrate may be exposed to a pretreatment reaction, such as a plasma, prior to selective deposition of Al and N containing material in step 320.

In some embodiments, the pretreatment process may be the same as the pretreatment process 110 and / or 210 described herein with respect to FIGS. In some embodiments, the pretreatment process may include exposing the substrate to a pretreatment reagent. In some embodiments, the pretreatment reagent may comprise hydrogen. In some embodiments, the pretreatment reagent comprises a hydrogen radical, a hydrogen atom, a hydrogen plasma, or a combination thereof. In some embodiments, the pretreatment reagent may comprise a plasma generated from a gas, including H ₂ .

In some embodiments, a plasma is formed in the reactor. In some embodiments, the plasma may be formed on the top of the substrate or in situ in proximity to the substrate. In another embodiment, the plasma is formed in the remote plasma generator upstream of the reaction chamber, and the plasma products are directed to the reaction chamber and contact the substrate. As will be appreciated by those skilled in the art, in the case of remote plasma, the path to the substrate can be optimized to maximize electronically neutral species and minimize ion survival before reaching the substrate.

In some embodiments, the processed substrate is not exposed to the ambient environment prior to the start of the optional deposition step 320 after the pretreatment process 310. In some embodiments, the treated substrate is not exposed to air prior to the start of the selective deposition process at step 320 after the pretreatment process 310. [

In some embodiments, the pretreatment process can be used to improve the selectivity of the subsequent selective deposition process. In some embodiments, the pretreatment process may enhance the selective deposition of Al and N containing materials on a first surface relative to a second, different surface, such as the first and second surfaces described herein. In some embodiments, the pretreatment process may improve the selectivity of subsequent selective deposition processes by a factor greater than about 2, greater than about 5, or greater than about 10.

In some embodiments, the pretreatment process 310 may be performed in the same reaction chamber or reactor as the subsequent selective deposition step 320. [ In some embodiments, the pretreatment process 310 may be performed in a reaction chamber or reactor that is different from the subsequent selective deposition step 320. [

Referring again to FIG. 3, in step 320, Al and N containing materials are selectively deposited on the first surface of the substrate relative to the second surface. In some embodiments, selectively depositing the Al and N containing material in step 320 may include a selective deposition process that includes at least one deposition sub-cycle, wherein the at least one sub-cycle includes a first gaseous aluminum precursor and a second gaseous precursor And sequentially contacting the substrate with the second gaseous nitrogen precursor alternately. In some embodiments, the deposition sub-cycle may be repeated 1 to 1000 times, 1 to 500 times, 1 to 300 times, 1 to 200 times, 1 to 50 times, 1 to 100 times, or 1 to 50 times.

In some embodiments, selectively depositing Al and N containing material in step 320 may include, for example, the selective deposition process described herein with respect to FIGS. In some embodiments, selectively depositing the Al and N containing material in step 320 can include an ALD deposition process that includes at least one sub-cycle, wherein the at least one sub-cycle includes: :

Contacting the substrate with a first gaseous precursor comprising Al;

Removing excess first precursor and reaction byproducts from the substrate when excess first precursor and reaction byproducts are present;

Contacting the substrate with a second gaseous precursor comprising nitrogen;

Removing an excess of the second precursor and any gaseous byproducts from the substrate; And

Optionally repeating the contacting and removing steps until an Al and N containing material of desired thickness is formed.

In some embodiments, selectively depositing the Al and N containing material in step 320 can include an ALD deposition process that includes at least one sub-cycle, wherein the at least one sub-cycle includes: :

Contacting a substrate with a first gaseous precursor comprising trimethylaluminum (TMA);

Removing excess first precursor and reaction byproducts from the substrate when excess first precursor and reaction byproducts are present;

Contacting the substrate with a second gaseous precursor comprising NH ₃ ;

Removing an excess of the second precursor and any gaseous byproducts from the substrate; And

Optionally repeating the contacting and removing steps until an Al and N containing material of desired thickness is formed.

In some embodiments, selectively depositing the Al and N containing material in step 320 may include one or more sub-cycles. Some embodiments include at least about 5 sub-cycles, at least about 10 sub-cycles, at least about 50 sub-cycles, at least about 100 sub-cycles, at least about 150 sub-cycles, at least about 200 sub- Cycle, at least about 500 sub-cycles, or at least about 1000 sub-cycles. In some embodiments, the selective deposition sub-cycle may be repeated until the selective deposition sub-cycle is no longer selective. In some embodiments, the selective deposition sub-cycle may be repeated until the selective deposition sub-cycle is no longer highly selective. In some embodiments, the selective deposition sub-cycle may be repeated until the selective deposition sub-cycle loses a significant amount of selectivity. In some embodiments, until the selective deposition sub-cycle no longer achieves the desired level of selectivity, for example, the selective deposition sub-cycle has a selectivity of about 50% selectivity, about 40% selectivity, The selective deposition sub-cycle can be repeated until no more than about 20% selectivity, about 10% selectivity, about 5% selectivity, about 2% selectivity, about 1% . That is, in some embodiments, selectively depositing Al and N-containing material in step 320 may be performed such that the sub-cycle no longer selectively deposits Al and N-containing material on the first surface of the substrate relative to the second surface And repeating the selective deposition sub-cycle, for example, an ALD deposition cycle as described herein, until it is no longer possible. In some embodiments, selective deposition of Al and N-containing material in step 320 may be accomplished by selective sub-cycles, such as ALD deposition as described herein, until the selectivity of the sub-cycle falls below a predetermined selectivity And repeating the cycle. For example, in some embodiments, selective deposition of Al and N containing material in step 320 may be performed in less than about 50%, less than about 25%, less than about 15%, less than about 10% Cycle of the selective deposition sub-cycle until it has a selectivity of less than about 5%, less than about 2%, less than about 1%, or below.

After selectively depositing the Al and N containing material in step 320, the deposited Al and N containing material is etched, for example, by etching through step 330. [ In some embodiments, the etch process substantially removes all of the deposited Al and N containing material from the second surface of the substrate and does not substantially remove all of the deposited Al and N containing material from the first surface of the substrate. In some embodiments, the etch process may remove Al and N containing materials of the same or similar thickness or thickness from the first and second surfaces of the substrate, but in step 320, the Al and N containing material is removed 1 < / RTI > surface, at least some of the thickness of the Al and N containing material remains on the first surface of the substrate while all of the Al and N containing material that has been deposited on the second surface of the substrate, All are removed by the etching process at step 330.

In some embodiments, the step of etching the deposited Al and N containing material in step 330 may include a step of subjecting the deposited Al and N containing material to a gaseous etch process. In some embodiments, the gas-phase etch process may be a periodic vapor etch process. In some embodiments, the etch process may include an atomic layer etch (ALE) process. In some embodiments, more than a sub-monolayer of material can be removed from the substrate by an atomic layer etch (ALE) process that includes contacting the substrate surface with at least one gaseous reactant in a reaction space. In some embodiments, one or more gaseous halide reactants are used. Halide reactants can be metal halides or non-metal halides, half metal halides, half / non-metal oxy halides, and organic (oxy) halides. In some embodiments, surface contamination such as B or C contamination can be removed from the substrate surface.

In some embodiments, the ALE process comprises alternately contacting the substrate with at least a first and a second gaseous reactant in a reaction space. In some embodiments, at least one of the gaseous reactants is a halide reactant. One or more etch cycles or sub-cycles may be provided in the ALE process as part of the selective deposition process or selective deposition super-cycle. In some embodiments, the etch cycle includes exposing the substrate to two different reactants. In some embodiments, the etch cycle includes exposing the substrate to three different reactants. In some embodiments, the etch cycle includes exposing the substrate to four different reactants. In some embodiments, the etch cycle includes exposing the substrate to at least five different reactants. In some embodiments, the reactant exposures are sequential. Each step of exposing the reactants can be separated by purging the reaction space or by pumping down the reaction chamber to remove reaction by-products and excess reactants.

In some embodiments, the substrate to be etched is exposed to one or more reactants selected from halides, oxygen compounds, oxygen scavengers, halide exchange drivers, ligand exchangers and metal organic or inorganic reactants. The oxygen compound may include, for example, H ₂ O, O ₂ or O ₃ . The oxygen scavenger or halide exchange driver may comprise, for example, Ch _y CI _x or CCl ₄ . In some embodiments, the oxygen scavenger or halide exchange driver is a halide as described herein, including a non-metallic (or semimetal) halide. The ligand exchanger, or metal or inorganic reactant, may comprise, for example, Hacac, or TMA / Sn (acac) ₂ . In some embodiments, the ligand exchanger can be a halide as described herein, including a non-metallic or semimetal halide.

In some embodiments, the etch cycle includes a saturating, self-limiting adsorption step in which the substrate is contacted with at least one gaseous reactant, such as a halide reactant. For example, after the substrate is contacted with the first gaseous reactant, a second exposure step may be performed in which the substrate is contacted with the second gaseous reactant. In the first adsorption step, the first reactant is adsorbed on the substrate to be etched in a self-limiting manner. The second exposure step then leads to the formation of volatile byproducts comprising adsorbate atoms, second precursor atoms and some atoms from the etched surface. In this way, the etching of the desired material on the substrate surface can be finely controlled.

In some embodiments, the reaction is not self limiting. However, the etching can be controlled by adjusting the amount of one or more reactants.

In some embodiments, the vapor phase reaction is avoided by alternately feeding the precursors sequentially into the reaction chamber. The gaseous reactants are separated from each other in the reaction chamber, for example, by removing excess reactants and / or reaction by-products from the reaction chamber between the reactant pulses. The reactants can be removed from proximity to the substrate surface using purge gas and / or vacuum. In some embodiments, excess reactants and / or reactant by-products are removed from the reaction space, for example, by purging with an inert gas. Due to the separation of reactants and the self-limiting nature of the reaction, less than one monolayer of material is typically removed in each ALE etching cycle. However, in some embodiments, material exceeding one monolayer can be removed in each cycle. In some embodiments, the pulses of reactants may be partially or completely superimposed. For example, in some embodiments, one or more additional reactants are provided intermittently at desired intervals, while one reactant can flow continuously into the reaction space.

In some embodiments, the ALE method disclosed herein is a thermal etch process that is contrasted with a plasma etch process. Thus, the plasma reactant is not used in this thermal ALE etch cycle. Although referred to as the thermal ALE process to differentiate the process using the plasma reactants, in some embodiments, the ALE reaction may have zero activation energy, and thus no additional thermal energy may be required. Thus, the reaction may be referred to as a chemical etching process. The thermal ALE method may be more preferable than the plasma ALE method, depending on the situation, since the thermal ALE method may less damage the lower substrate. The thermal ALE method also enables isotropic etching of non-visible (NLOS) features.

However, in some embodiments, the etching process may include an ALE process that includes a plasma. In some embodiments, the ALE process may include contacting the deposited Al and N containing material with at least one gaseous etch reactant. In some embodiments, the etching process may be a dry etching process, such as a reactive ion etching process. In some embodiments, the dry etching process may be a thermal dry etching process. In some embodiments, the dry etching process may involve the use of a plasma.

In some embodiments, the etching process of step 330 may include an ALE process that includes one or more etch sub-cycles, wherein at least one etch sub-cycle may be used to separate the deposited Al and N containing material into a first gas- 2 gas phase etch reactant. In some embodiments, the etch sub-cycle may be repeated 1 to 1000 times, 1 to 500 times, 1 to 300 times, 1 to 200 times, 1 to 50 times, 1 to 100 times, or 1 to 50 times.

In some embodiments, the etching process of step 330 may comprise an ALE process comprising one or more etch sub-cycles, the etch sub-cycle comprising:

Contacting the substrate with a first gas phase etch reactant;

Removing excess first etch reactants and reaction by-products from the substrate when excess first etch reactants and reaction by-products are present;

Contacting the substrate with a first gas phase etch reactant;

Removing excess second etch reactants and reaction byproducts from the substrate when excess second etch reactants and reaction by-products are present; And

For example, selectively repeating the contacting and removing steps to etch the deposited Al and N containing material to a desired extent until the deposited Al and N containing material is substantially completely removed from the second surface of the substrate.

In some embodiments, the etching process of step 330 may comprise an ALE process comprising one or more etch sub-cycles, the etch sub-cycle comprising:

Contacting the substrate with a first gas phase halide etch reactant, such as NF ₃ ;

Removing excess first etch reactants and reaction by-products from the substrate when excess first etch reactants and reaction by-products are present;

Contacting the substrate with a second gaseous etch reactant comprising Al, such as TMA;

Removing excess second etch reactants and reaction byproducts from the substrate when excess second etch reactants and reaction by-products are present; And

For example, selectively repeating the contacting and removing steps to etch the deposited Al and N containing material to a desired extent until the deposited Al and N containing material is substantially completely removed from the second surface of the substrate.

In some embodiments, the etch sub-cycle may be repeated one or more times. Some embodiments include at least about 5 sub-cycles, at least about 10 sub-cycles, at least about 50 sub-cycles, at least about 100 sub-cycles, at least about 150 sub-cycles, at least about 200 sub- Cycle, at least about 500 sub-cycles, or at least about 1000 sub-cycles. In some embodiments, the etch sub-cycle is such that all of the deposited Al and N containing material is substantially removed from the second surface of the substrate and all of the deposited Al and N containing material is not substantially removed from the first surface of the substrate Can be repeated until.

According to some embodiments, each sub-cycle has a temperature ranging from about 20 to about 1200 DEG C, from about 50 to about 800 DEG C, from about 75 to about 600 DEG C, from about 300 to about 500 DEG C, or from about 350 to about 450 DEG C Lt; / RTI > In some embodiments, the temperature is greater than about 20 占 폚, 50 占 폚 or 100 占 폚, but less than about 1000 占 폚, 800 占 폚, 600 占 폚, or 500 占 폚. In some embodiments, the cycle is performed at a temperature of about 450 < 0 > C.

The pressure in the reaction chamber is generally from about 10 ^-9 Torr to about 760 Torr, or from about 0.001 Torr to about 100 Torr. However, as may be determined by those skilled in the art under given circumstances, in some cases the pressure may be higher or lower than this range. In some embodiments, a pressure of less than 2 torr is used.

In some embodiments, the etchant reacts with the surface having the surface to be etched for about 0.01 seconds to about 60 seconds, about 0.05 seconds to about 30 seconds, about 0.05 seconds to about 5.0 seconds, about 0.1 seconds to about 3 seconds, or about 0.2 Lt; / RTI > to about 1.0 second. In some embodiments, the etchant reacts with the substrate surface to be etched for about 0.05 seconds to about 5.0 seconds, for about 0.1 seconds to about 3 seconds, for about 0.2 seconds to about 1.0 second. In some embodiments, the contact time may be greater than about 60 seconds. However, depending on the reactor type, the material to be etched and other process conditions, such as surface area and temperature, the contact time of the etchant may even be longer than about 10 seconds. In some embodiments, the contact time may be in minutes. The optimal contact time can be readily determined by one skilled in the art based on the particular circumstances.

In some embodiments, if there are excess reactants and reaction by-products, excess reactants and reaction by-products may be removed from the substrate, for example, by purging the reaction chamber with an inert purge gas. In some embodiments, the reaction chamber may be purged by stopping the flow of the etching reactant while continuing to flow the carrier gas or purge gas for a period of time sufficient to diffuse or purgate excess reactants and reaction by-products from the reaction space. In some embodiments, excess etching reactants and reaction byproducts are purged with an inert gas such as helium or argon. In some embodiments, the substrate may be moved from the reaction space containing the second reactant to another reaction space. In some embodiments, the pulse of the purge gas may be from about 0.1 second to about 10 seconds, from about 0.1 seconds to about 4 seconds, or from about 0.1 seconds to about 0.5 seconds.

In some embodiments, the first gas phase etch reactant may comprise a halide. In some embodiments, the first gas phase etch reactant may comprise NF ₃ . In some embodiments, the first gas phase reaction may include NbF _5. In some embodiments, the first gas phase etch reactant may not comprise a plasma or an excited reactant. In some embodiments, the second gas phase etch reactant may comprise aluminum. In some embodiments, the second gas phase etch reactant may comprise one of triethylaluminum (TTBA), trimethylaluminum (TMA), or triethylaluminum (TEA). In some embodiments, the second gas phase etch reactant may be the same as the vapor precursor of optional deposition step 320. In some embodiments, the second gas phase etch reactant may comprise TMA. In some embodiments, the second gas phase etch reactant may not comprise a plasma or an excited reactant.

In some embodiments, the etch step 330 is performed in the same reaction space as the optional deposition step 320. However, in some embodiments, the etch step 330 may be performed in a different reaction space than the optional deposition step 320. In some embodiments, selectively depositing AlN in step 340 until the desired thickness of Al and N containing material is formed on the first surface of the substrate relative to the second surface, and selectively etching the substrate etch step have. That is, the super-cycle 301 may be selectively repeated until an Al and N containing material of a desired thickness is formed on the first surface of the substrate relative to the second surface. In some embodiments, after the etch step 330, the substrate is not exposed to the ambient environment before beginning another super-cycle 301. In some embodiments, after the etching step 330, the substrate is not exposed to air prior to initiating another super-cycle 301.

The first precursor

A number of different first precursors can be used as the first precursors in the selective deposition cycle and / or the selective deposition sub-cycle in the selective deposition process described herein. In some embodiments, the first precursor is an organometallic compound comprising aluminum. In some embodiments, the first precursor is an alkyl aluminum compound. In some embodiments, the first precursor does not comprise any other metals other than aluminum.

In some embodiments, the first precursor is a compound having the formula R ₃ Al, wherein R is an alkyl group. Each R may be independently selected from the list of methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, and tertbutyl groups. Each R is preferably independently selected from a methyl group, an ethyl group and a tertbutyl group. In some embodiments, each R may be independently selected from C ₁ -C ₄ alkyl group.

In some embodiments, the first precursor comprises Me ₃ Al, Et ₃ Al, or ^t Bu ₃ Al. In some embodiments, the first precursor is tri-butyl-aluminum (TTBA). As mentioned above, in some embodiments, the first precursor is trimethyl aluminum (TMA).

In some embodiments, the first precursor is not a halide. In some embodiments, the first precursor does not include all ligands but at least one ligand contains a halogen. In some embodiments, the first precursor comprises one chlorine ligand and at least two alkyl ligands. In some embodiments, the first precursor is a AlCl _3.

In some embodiments, the first precursor may include hydrogen as at least one ligand, not all ligands. In some embodiments, the first precursor may comprise at least one hydrogen ligand and at least one alkyl ligand.

In some embodiments, the first precursor does not contain nitrogen. In some embodiments, the first precursor does not comprise silicon. In some embodiments, the first precursor does not contain oxygen. In some embodiments, the first precursor does not comprise nitrogen, silicon, or oxygen.

The second precursor

In some embodiments, the second precursor comprises a nitrogen-hydrogen bond. In some embodiments, the second precursor is ammonia (NH _3). In some embodiments, the second precursor is a nitrogen molecule. In some embodiments, the second precursor is a nitrogen containing plasma. In some embodiments, the second precursor is a nitrogen containing plasma, such as a nitrogen and hydrogen containing plasma. In some embodiments, the second precursor comprises activated or excited nitrogen species. In some embodiments, the second precursor may be provided with a nitrogen-containing gas pulse, which may be a mixture of nitrogen reactant and an inert gas, such as argon.

Integration

The Al and N containing materials of this disclosure can be used in a variety of semiconductor applications. For example, Al and N containing materials may be particularly useful as etch stop layers, such as contact etch stop layers, in self-aligned contact formation processes. The self-aligned source / drain contacts may be used to provide misalignment margins for contact lithography. However, standard self-aligned contact processes require additional processing steps, such as multiple metal recessing steps, SiN filling steps, and SiN polishing steps using chemical-mechanical planarization.

In addition, the need for additional scaling of the SiN sidewall spacers and etch stop layers in standard self-aligned contact processes due to further miniaturization of the devices may result in a risk of shorting between contacts and metal gates due to over-etching of the spacer or etch stop layer .

In some embodiments, the Al and N containing materials of the present disclosure can be used as etch stop layers in self-aligned contact processes that do not include metal recesses. In some embodiments, the Al and N containing materials of the present disclosure are etch resistant. FIG. 4 illustrates a process flow for a self-aligned contact process comprising an Al and N containing material protective layer, a capping layer, or an etch stop layer according to some embodiments. In some embodiments, the process for forming the self-aligned contact 400 proceeds as follows:

In step 401, a semiconductor substrate is provided that includes a first surface overlying a source / drain region and a second different surface;

In step 402, an Al and N containing protective layer or etch stop layer, such as AlN, is selectively deposited on the first surface of the substrate relative to the second surface;

In step 403, the second surface is removed using, for example, a wet etch process;

At step 404, a contact is formed on the source / drain region of the substrate instead of the removed second surface.

According to some implementations, in step 401, a substrate comprising a semiconductor is provided. The semiconductor substrate includes a first surface and a different second surface. In some embodiments, the first surface comprises a conductive surface. In some embodiments, the first surface comprises at least one metal nitride. In some embodiments, the first surface may comprise a surface of a conductive gate and / or a surface of a spacer. For example, in some embodiments, the first surface may comprise a TiN gate and a SiN spacer. The second surface is preferably a dielectric surface. In some embodiments, the dielectric comprises SiO ₂ . In some embodiments, the second surface is a dummy contact overlying the source / drain region. In some embodiments, the SiO ₂ dummy contacts are over the source / drain regions.

In some embodiments, the semiconductor substrate undergoes a standard process through gate polishing. That is, the semiconductor substrate may undergo a standard alternate metal gate process flow to form the source, gate and drain as is well known in the art. In some embodiments, the semiconductor substrate may undergo a chemical-mechanical planarization process.

In step 402, a protective layer or etch stop layer containing Al and N is selectively deposited on the first surface of the substrate relative to the second surface. In some embodiments, the Al and N containing protective material is formed on the TiN gate and the SiN spacer. In some embodiments, the Al and N containing protective material is formed directly on the TiN gate and the SiN spacer.

In some embodiments, the Al and N containing protective layers are deposited by the ALD process described herein. In some embodiments, the substrate is in turn sequentially in contact with a first precursor comprising Al and a second precursor comprising N. In some embodiments, the Al and N containing protective layer comprises AlN. In some embodiments, the Al and N containing protective layer comprises an AlN thin film.

In some embodiments, the deposition of the Al and N containing protective layer on the first surface of the substrate relative to the second surface of the substrate is at least about 90% selective, at least about 95% selective, at least about 96%, 97% Or 99% or more. In some embodiments, deposition of the Al and N containing material occurs only on the first surface and not on the second surface. In some embodiments, the deposition on the first surface of the substrate relative to the second surface of the substrate is at least about 80% selective or at least about 50% selective.

In some embodiments, the Al and N containing protective layer or etch stop layer is deposited on the first surface of the substrate to have a particular thickness. A suitable thickness may be greater than or equal to about 0.1 nm and less than or equal to about 10 nm. In some embodiments, the thickness will be from about 0.1 nm to about 5 nm. In some embodiments, the thickness will be from about 1 nm to about 5 nm. In some embodiments, the thickness will be from about 1 nm to about 3 nm. In some embodiments, the thickness will be from about 2 nm to about 3 nm. A suitable thickness may be from about 0.1 nm to about 10 nm. In some embodiments, a suitable thickness will be a complete layer thickness (i.e., a thickness that leaves no gap) on the substrate surface. Thus, the actual thickness of the complete layer may vary depending on the type of precursors used to obtain the Al and N containing material.

At step 403, the second surface of the substrate is removed, for example, using a wet etch process. In some embodiments, the second surface of the substrate is removed by etching using dHF. For example, in some embodiments, the first and second surfaces of the substrate are exposed to dHF and the second surface of the substrate is removed while the Al and N containing protective layer protects the underlying gates and spacers from etching. The Al and N containing protective layer can function as an etch stop layer because the Al and N containing protective layer has a lower wet etch rate than the wet etch rate of the second dielectric surface described herein.

Continuing with reference to FIG. 4, a contact may be formed instead of the second surface that is now removed on the source / drain regions in step 404. In some embodiments, the contacts may be formed directly over the source / drain regions. In some embodiments, the contact includes a silicide material or a titanium-containing material, such as Ti or TiN. According to some embodiments, the contact may be formed according to any method known in the art or a method to be developed in the future. For example, the Ti contact can be formed by physical vapor deposition (PVD) or the TiN contact can be formed by atomic layer deposition (ALD).

In some embodiments, after formation of the contacts or contacts, the substrate may optionally undergo further processing or processing steps.

In some embodiments, the Al and N containing materials of this disclosure may be used as etch stop layers in self-aligned contact processes that do not include metal recesses. FIG. 5 illustrates a process flow for a self-aligned contact process comprising an Al and N containing material passivation layer or etch stop layer in accordance with some embodiments. In some embodiments, the process for forming the self-aligned contact 500 proceeds as follows:

In step 501, a semiconductor substrate is provided that includes a first surface overlying a source / drain region and a second different surface;

In step 502, a portion of the first surface is removed to create a recess therein;

In step 503, a protective layer or etch stop layer, such as AlN, containing Al and N is selectively deposited on the first surface of the substrate relative to the second surface;

At step 504, the second surface is formed on the source / drain region of the substrate, instead of the second surface being removed and removed using, for example, a wet etch process.

According to some implementations, in step 501, a substrate comprising a semiconductor is provided. The semiconductor substrate includes a first surface and a different second surface. In some embodiments, the first surface comprises a conductive surface. In some embodiments, the first surface comprises at least one metal nitride. In some embodiments, the first surface may comprise a surface of a conductive gate and / or a surface of a spacer. For example, in some embodiments, the first surface may comprise a TiN gate and a SiN spacer. The second surface is preferably a dielectric surface. In some embodiments, the dielectric comprises SiO ₂ . In some embodiments, the second surface is a dummy contact overlying the source / drain region. In some embodiments, the SiO ₂ dummy contacts are over the source / drain regions.

In some embodiments, the semiconductor substrate undergoes a standard process through gate polishing. That is, the semiconductor substrate may undergo a standard alternate metal gate process flow to form the source, gate and drain as is well known in the art. In some embodiments, the semiconductor substrate may undergo a chemical-mechanical planarization process.

According to some implementations, at step 502, a portion of the first surface is removed to create a recess therein. In some embodiments, a portion of the first surface removed is a metal nitride. In some embodiments, a portion of the first surface removed is SiN. In some embodiments, a portion of the removed first surface may comprise a spacer, such as an SiN spacer. In some embodiments, about 0.1 nm to about 30 nm of a portion of the first surface is removed to produce a recess having a depth of about 0.1 nm to about 30 nm. In some embodiments, about 0.1 nm to about 20 nm of a portion of the first surface is removed to produce a recess having a depth of about 0.1 nm to about 20 nm. In some embodiments, about 1 nm to about 10 nm of a portion of the first surface is removed to produce a recess having a depth of about 1 nm to about 10 nm.

At step 503, a protective layer or etch stop layer containing Al and N is then selectively deposited on the first surface of the substrate relative to the second surface. In some embodiments, the Al and N containing protective material is formed on the TiN gate and the SiN spacer. In some embodiments, the Al and N containing protective material is formed directly on the TiN gate and the SiN spacer.

In some embodiments, the Al and N containing protective layers are deposited by the ALD process described herein. In some embodiments, the substrate is in turn sequentially in contact with a first precursor comprising Al and a second precursor comprising N. In some embodiments, the Al and N containing protective layer comprises AlN. In some embodiments, the Al and N containing protective layer comprises an AlN thin film.

The selectivity can be provided as a percentage calculated by [(deposition on the first surface) - (deposition on the second surface)] / (deposition on the first surface). Deposition can be measured in one of a variety of ways. In some embodiments, the deposition may be provided as a measured thickness of the deposited material. In some embodiments, deposition may be provided as a measured amount of deposited material. In some embodiments, the deposition of the Al and N containing protective layer on the first surface of the substrate relative to the second surface of the substrate is at least about 90% selective, at least about 95% selective, at least about 96%, 97% Or 99% or more. In some embodiments, deposition of the Al and N containing material occurs only on the first surface and not on the second surface. In some embodiments, the deposition on the first surface of the substrate relative to the second surface of the substrate is at least about 80% selective or at least about 50% selective.

In some embodiments, the Al and N containing protective layer or etch stop layer is deposited on the first surface of the substrate to have a particular thickness. A suitable thickness may be greater than or equal to 0.1 nm and less than or equal to about 10 nm. In some embodiments, the thickness will be from about 0.1 nm to about 5 nm. In some embodiments, the thickness will be from about 1 nm to about 5 nm. In some embodiments, the thickness will be from about 1 nm to about 3 nm. In some embodiments, the thickness will be from about 2 nm to about 3 nm. A suitable thickness may be greater than or equal to about 0.1 nm and less than or equal to about 10 nm. In some embodiments, a suitable thickness will be a complete layer thickness (i.e., a thickness that leaves no gap) on the substrate surface. Thus, the actual thickness of the complete layer may vary depending on the type of precursors used to obtain the Al and N containing material.

At step 504, the second surface of the substrate is removed, for example, using a wet etch process. In some embodiments, the second surface of the substrate is removed by etching using dHF. For example, in some embodiments, the first and second surfaces of the substrate are exposed to dHF and the second surface of the substrate is removed while the Al and N containing protective layer protects the underlying gates and spacers from etching. The Al and N containing protective layer can function as an etch stop layer because the Al and N containing protective layer has a lower wet etch rate than the wet etch rate of the second dielectric surface described herein. A subsequent contact is formed on the source / drain region of the substrate in place of the now removed second surface. In some embodiments, the contacts may be formed directly over the source / drain regions. In some embodiments, the contact includes a silicide material or a titanium-containing material, such as Ti or TiN. According to some embodiments, the contact may be formed according to any method known in the art or a method to be developed in the future. For example, the Ti contact can be formed by physical vapor deposition (PVD) or the TiN contact can be formed by atomic layer deposition (ALD).

In some embodiments, after formation of the contacts or contacts, the substrate may optionally undergo further processing or processing steps.

Example 1

In this embodiment, AlN was selectively deposited on the first surface of the substrate relative to the second different surface of the substrate. In this example, the first surface of the substrate comprised TiN deposited by ALD and the second surface of the substrate comprised SiO ₂ deposited by plasma enhanced vapor deposition (PEALD). Sample AlN films were selectively deposited by an ALD process using trimethyl aluminum (TMA) as the first precursor and NH ₃ as the second precursor. Each deposition cycle was performed at a temperature of 375 DEG C and a reaction chamber pressure of 2 torr. Each deposition cycle included a first precursor pulse of 0.5 seconds and a second precursor pulse of 2 seconds. After each pulse TMA, it was purged with a reaction chamber for 3 seconds, and was purged each NH ₃ pulse after the reaction chamber for at least 2 seconds.

Samples were deposited using an ALD process consisting of 30 to 70 deposition cycles. As shown in FIG. 6, the thickness of the material deposited on the first TiN surface was measured and compared to the thickness of the material deposited on the second SiO ₂ surface. The ratio of the material thickness deposited on the first TiN surface to the second SiO ₂ surface defines the selectivity of the deposition process. Figure 6 shows that the ratio of AlN deposited on the first surface to the second surface in the ALD process consisting of 70 deposition cycles is about 8.5: 1 (indicating a selectivity of about 89%).

Example 2

In this embodiment, AlN was selectively deposited on the first surface of the substrate relative to the second different surface of the substrate. In this embodiment, the first surface of the substrate including the TiN was deposited by ALD on a second surface of the substrate comprises a SiO ₂ was deposited by PEALD. Additional samples were prepared in which AlN was selectively deposited on a first surface comprising TiN deposited by ALD, relative to a second surface comprising native silicon oxide. Sample AlN films were selectively deposited by an ALD process using trimethyl aluminum (TMA) as the first precursor and NH ₃ as the second precursor. Each deposition cycle was performed at a temperature of 375 DEG C and a reaction chamber pressure of 2 torr. Each deposition cycle included a first precursor pulse of 0.5 seconds and a second precursor pulse of 1 second. After each pulse TMA, it was purged with a reaction chamber for 3 seconds, and was purged each NH ₃ pulse after the reaction chamber for at least 2 seconds.

Samples were deposited using an ALD process consisting of 70-150 deposition cycles. As shown in FIG. 7, the thickness of the material deposited on the first TiN surface was measured and compared to the thickness of the material deposited on the second SiO ₂ and naturally oxidized surfaces. Figure 7 shows that the ratio of AlN deposited on the first surface to the second PEALD SiO ₂ surface in the ALD process consisting of 130 deposition cycles is about 43: 1 (indicating a selectivity of about 98%). Indicates that the ratio of AlN deposited on the first surface to the second natural oxide surface in the ALD process consisting of 110 deposition cycles is about 3: 1 (indicating a selectivity of about 75%).

Example 3

In this embodiment, AlN was selectively deposited on the first surface of the substrate relative to the second different surface of the substrate. The first surface of the substrate comprised TiN deposited by ALD and the second surface of the substrate contained natural silicon oxide. Prior to the deposition of AlN, the substrate underwent a plasma treatment process. The substrate was exposed to direct plasma generated at an output of 50 W for 10 seconds. Plasma was generated from O ₂ .

A sample AlN film was selectively deposited by an ALD process using trimethyl aluminum (TMA) as a first precursor and NH ₃ as a second precursor. Each deposition cycle was performed at a temperature of 375 DEG C and a reaction chamber pressure of 2 torr. Each deposition cycle included a first precursor pulse of 0.5 seconds and a second precursor pulse of 1 second. After each pulse TMA, it was purged with a reaction chamber for 3 seconds, and was purged each NH ₃ pulse after the reaction chamber for at least 2 seconds. A sample was deposited using an ALD process consisting of 110 deposition cycles.

Referring to Figure 8, the thickness of the material deposited on the first plasma treated TiN surface was measured and compared to the thickness of the material deposited on the second plasma treated natural oxide surface. Fig. 8 also shows data obtained from the samples of Example 2. Fig. After 110 deposition cycles, the thickness of the material deposited on the first TiN surface was compared to the thickness of the material deposited on the first plasma-treated TiN surface after 110 deposition cycles. No significant change in AlN thickness is observed. However, a significant change in AlN thickness is observed when the thickness of the material deposited on the second native oxide surface after 110 deposition cycles is compared to the thickness of the material deposited on the second plasma treated native oxide surface. After the plasma treatment, no deposition is essentially observed on the second surface relative to the first surface. For an ALD process consisting of 110 deposition cycles, the ratio of AlN deposited on the first plasma treated TiN surface to the second plasma treated native oxide surface is about 33: 1, which is the same selective deposition without plasma treatment Comparing with the process, the choice over 10x is also improved.

Additional samples were prepared, wherein the first surface of the substrate contained TiN deposited by ALD and the second surface of the substrate contained native silicon oxide. Prior to the deposition of AlN, the substrates undergo a plasma treatment process. The substrates were exposed to direct plasma generated at an output of 50 W to 300 W for 3 seconds to 10 seconds. Plasma was generated from O ₂ . The thickness of AlN deposited on the first surface of each substrate was compared to the thickness of the deposited material on the second surface and the selectivity for each sample was calculated. The results are shown in Table 1 below.

The selectivity of AlN deposited by ALD when direct plasma processing conditions were varied O2 plasma output (watts) O2 Direct plasma exposure time (seconds) Number of cycles Thickness of AlN deposited on TiN (nm) The thickness (nm) of AlN deposited on the native oxide Selectivity 50 10 110 5.21 0.16 32.6 300 10 110 4.36 0.2 21.8 300 3 110 4.40 0.43 10.2

From these results, it was observed that the selectivity of AlN decreased as the direct plasma pretreatment power increased, while the selectivity increased as the direct plasma exposure time increased.

Example 4

In this embodiment, AlN was selectively deposited on the first surface of the substrate relative to the second different surface of the substrate. In this embodiment, the first surface of the substrate including the TiN was deposited by ALD on a second surface of the substrate comprises a SiO ₂ was deposited by PEALD. The second AlN on a first surface including a relative, a TiN deposited by ALD on a second surface that hayeotneun to prepare additional samples, in which comprises a SiO ₂ deposited by PEALD been selectively deposited. Sample AlN films were selectively deposited by an ALD process using trimethyl aluminum (TMA) as the first precursor and NH ₃ as the second precursor. Each deposition cycle was performed at a temperature of 390 DEG C and a reaction chamber pressure of 2 torr. Each deposition cycle included a first precursor pulse of 0.5 seconds and a second precursor pulse of 1 second. After each TMA pulse, the reaction chamber was purged for 5 seconds, and after each NH ₃ pulse, the reaction chamber was also purged for 5 seconds.

Samples were deposited using an ALD process consisting of 70 to 100 deposition cycles. As shown in FIG. 9, the thickness of the material deposited on the first TiN and W surfaces was measured and compared to the thickness of the material deposited on the second SiO ₂ surface. 9 is AlN deposited on the first surface comprises one of TiN or W represents a gajyeoteum a still higher selectivity than the SiO ₂ surface.

Example  5

In this embodiment, AlN was selectively formed on the first surface of the same substrate relative to the second different surface of the substrate. In this embodiment, the substrate comprised a W / SiO ₂ pattern, where the first surface of the substrate comprised W metal wirings formed on a silicon wafer. The second surface of the substrate comprised SiO ₂ deposited by plasma enhanced chemical vapor deposition (PECVD). Sample AlN films were formed on the first surface of the substrate by a process that included a super-cycle, referring to the process described herein, e.g., Figure 3, wherein the super-cycle comprises pretreating the substrate, And etching the deposited AlN so that all of the deposited AlN is substantially removed from the second surface and all of the deposited AlN is not substantially removed from the first surface. ≪ RTI ID = 0.0 > . The process involved four super-cycles.

According to some implementations and as described herein, the pretreatment step included exposing the substrate to a plasma generated from H ₂ at a temperature of 250 ° C. The selective deposition step includes an ALD process comprising a plurality of sub-cycles, wherein the plurality of sub-cycles comprise a first gaseous precursor according to some embodiments and comprising TMA and NH ₃ as described herein Gt; 375 < / RTI >< RTI ID = 0.0 > C. ≪ / RTI > The etch step comprises an ALE process comprising a plurality of sub-cycles, wherein the plurality of sub-cycles comprise a first gaseous etch reactant comprising NF ₃ and a second gaseous etch reactant comprising TMA, At a temperature of < RTI ID = 0.0 > The sub-cycles were repeated until all of the deposited AlN was substantially removed from the second surface and all of the deposited AlN was not substantially removed from the first surface.

10A shows a scanning electron microscope (SEM) image of the deposited AlN film. Although the AlN of around 15 nm formed on the first surface, including W, observable AlN on the second surface including a SiO ₂ was observed was not formed. 10B is a partial detail view of the substrate, showing one W wiring. The AlN film can be clearly observed on the W surface, but no AlN is observed on the adjacent SiO ₂ surface.

As used herein, the terms " approximately ", " about ", and " substantially ", as used herein, Amount, or characteristic that is close to the value, quantity, or characteristic. For example, the terms "about", "about", "generally", and "substantially" refer to not more than 10%, not more than 5%, not more than 1%, not more than 0.1%, not more than 0.01% Of the total amount. If the stated amount is zero (e.g., none, not present), the ranges described above may be in a specific range and may not be within a certain percentage of this value. For example, within 10 wt./vol.% of the stated value, within 5 wt./vol.% of the stated value, within 1 wt./vol.% of the stated value, Within 0.1 wt./vol.% or less, within 0.01 wt./vol.% of the stated value.

The terms " membrane " and " membrane " are used herein for the sake of simplicity. "Film" and "thin film" means any continuous or non-continuous structure and material deposited by the methods disclosed herein. For example, " membrane " and " thin film " may comprise 2D materials, nanorods, nanotubes or nanoparticles or even a single or a whole molecular layer or a partial or entire atomic layer or atomic and / or molecular clusters. The " film " and " thin film " may include a material or layer comprising a pinhole but may still be at least partially continuous.

Those skilled in the art will appreciate that numerous and various modifications can be made without departing from the spirit of the invention. The described features, structures, features, and precursors may be combined in any suitable manner. It is therefore to be clearly understood that the forms of the invention are illustrative only and are not intended to limit the scope of the invention. All variations and modifications are intended to fall within the scope of the invention as defined by the appended claims.

Claims (21)

1. A method for selectively forming AlN on a first surface relative to a different second surface, the method comprising one or more super-cycles, wherein the one or more super-cycles comprise:
Selectively depositing AlN on the first surface relative to the different second surface by at least one selective deposition sub-cycle;
Etching the deposited AlN by one or more thermal etch sub-cycles;
The super-cycle further comprises exposing the substrate to a pretreatment reactant prior to selectively depositing AlN; And
Wherein the AlN is selectively formed with a selectivity in excess of about 99% on the first surface of the substrate relative to a different second surface of the substrate. The method of claim 1, wherein in the super-cycle, the selective deposition sub-cycle and the thermal etch sub-cycle are repeated until an AlN thin film of desired thickness is deposited on the first surface. The method of claim 1, wherein the pretreatment reactant comprises a plasma. 4. The method of claim 3 wherein the plasma is generated from the way the gas containing H _2. The method of claim 1, wherein the at least one selective deposition sub-cycle comprises:
Contacting the substrate with a first gaseous precursor comprising Al; And
Contacting the substrate with a second gaseous precursor comprising nitrogen;
Wherein the AlN is deposited with a selectivity in excess of about 5% on a first surface of the same substrate relative to a second dielectric surface of the substrate. 6. The method of claim 5, wherein the selective deposition sub-cycle is repeated until a desired thickness of AlN is deposited on the first surface. 6. The method of claim 5, wherein the selective deposition sub-cycle is repeated until the selective deposition sub-cycle is no longer selective. 6. The method of claim 5, wherein the first gaseous precursor comprising aluminum comprises one of triethylaluminum (TTBA), trimethylaluminum (TMA), or triethylaluminum (TEA). According to claim 5, wherein the second gaseous precursor comprises NH _3. The method of claim 1, wherein the at least one etch sub-cycle comprises:
Contacting the substrate with a first gaseous halide etch reactant; And
Contacting the substrate with a second gas phase etch reactant comprising aluminum. 11. The method of claim 10, wherein the first vapor phase reactant is a halide etching include NF _3, or NbF _5. 11. The method of claim 10, wherein the second gas phase etch reactant comprising aluminum comprises trimethyl aluminum (TMA) or triethyl aluminum (TEA). 11. The method of claim 10, wherein the at least one etch sub-cycle is performed at a process temperature of about 300 < 0 > C. The method of claim 1, wherein the first surface comprises a W comprises the second surface of SiO _2. The method of claim 1, wherein the first surface comprises a TiN, and the second surface comprises SiO _2. 2. The method of claim 1, wherein the selective deposition sub-cycle is repeated from 1 to about 300 times;
Wherein the thermal etch sub-cycle comprises an atomic layer etch (ALE) process and is repeated from 1 to about 150 times. A method for selectively forming AlN on a first surface of a same substrate relative to a different second surface of the substrate, the method comprising a super-cycle, the super-cycle comprising:
A second gaseous precursor comprising nitrogen and a second gaseous precursor comprising aluminum such that the AlN is deposited with a selectivity in excess of about 5% on a first surface of the same substrate relative to a different second surface of the substrate A selective deposition sub-cycle comprising alternating sequentially contacting the substrate; And
And an atomic layer etch sub-cycle comprising alternating sequentially contacting the substrate with a second gaseous etch reactant comprising a first gaseous halide etch reactant and aluminum. 18. The method of claim 17, wherein the super-cycle is repeated one or more times. 18. The method of claim 17 wherein the super-cycle is the selective deposition sub-method further comprises the step of exposing the substrate to a plasma generated from a gas containing H ₂ before the cycle. The method of claim 17, wherein the first gaseous precursor containing aluminum comprises the TMA, and the second vapor phase precursor containing nitrogen comprises NH _3, and the first gas phase halide etching reaction may include a NF ₃ And the second gaseous etch reactant comprising aluminum comprises TMA. 18. The method of claim 17, wherein the first surface is a conductive surface and the second surface is a dielectric surface.

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