TW201934792A - Layer forming method - Google Patents

Abstract

There is provided a method of forming a layer, comprising depositing a seed layer on the substrate; and depositing a bulk layer on the seed layer. Depositing the seed layer comprises supplying a first precursor comprising metal and halogen atoms to the substrate; and supplying a first reactant to the substrate. Depositing the bulk layer comprises supplying a second precursor comprising metal and halogen atoms to the seed layer; and, supplying a second reactant to the seed layer.

Description

Layer formation method [Cross-reference to related patent applications]

This application is a partial continuation of US Non-Provisional Application No. 15 / 691,241 entitled “LAYER FORMING METHOD” filed on August 30, 2017, and claims to be filed on December 18, 2017 The benefit of US Provisional Patent Application No. 62 / 607,070, entitled "Layer Formation Method", both cases are incorporated herein by reference.

The present invention relates generally to a method for forming a layer on a substrate. More specifically, the present invention relates to sequentially repeating an atomic layer deposition (ALD) cycle or a chemical vapor deposition (CVD) procedure to form at least a portion of a layer on a substrate having gaps, the gaps being in the manufacturing process of features Generated. The layer on the substrate can be used for manufacturing semiconductor devices.

In atomic layer deposition (ALD) and chemical vapor deposition (CVD), a substrate is applied with a first precursor and a first reactant suitable for reacting to form a desired layer on the substrate. This layer can be deposited on the substrate to fill the gaps created during the manufacturing process.

In ALD, a substrate is exposed to a pulse of a first precursor and a single layer of the first precursor can be chemically adsorbed on the surface of the substrate. The surface position may be occupied by the entirety of the first precursor or by a fragment of the first precursor. This reaction can be a chemical self-limiting reaction because the first precursor does not adsorb on the substrate surface or does not react with a portion of the first precursor that has already adsorbed on the substrate surface. Then, excess The first precursor is purified by, for example, supplying an inert gas and / or removing the first precursor from the reaction chamber. Subsequently, the substrate is exposed to a pulse of a first reactant that chemically reacts with all or a portion of the adsorbed first precursor until the reaction is complete and the surface is covered with a single layer of reaction product.

It has been found that it may be necessary to improve the quality of the deposited layer.

An improved method for forming a deposited layer on a substrate may be needed. Therefore, a method of forming a layer may be provided, the method including: providing a substrate having a gap generated during a feature manufacturing process and depositing a seed layer on the substrate; and depositing a main body layer on the seed layer. Depositing the seed layer may include: supplying a first precursor including a metal and a halogen atom to the substrate; and supplying a first reactant to the substrate, wherein the first precursor reacts with a portion of the first reactant to Forming at least a portion of the seed layer. Depositing the host layer may include: supplying a second precursor including a metal and a halogen atom to the seed layer; and supplying a second reactant to the seed layer, wherein the second precursor and a portion of the second reactant Reacting to form at least a portion of the host layer on the seed layer. The first and second precursors may be different.

By having different first and second precursors for the seed layer and the host layer, the characteristics of the seed layer and the host layer can be optimized, thereby improving the quality of the overall layer. The first and second reactants may be the same and include a hydrogen atom.

In some other specific examples, a method for semiconductor processing is provided. The method includes depositing a metal layer in a gap in a substrate, thereby filling the gap.

These and other features, aspects, and advantages of the invention disclosed herein are described below with reference to the drawings of certain specific examples, which are intended to illustrate and not limit the invention.

1a and 1b show a flowchart illustrating a method for depositing a layer according to a specific example.

FIG. 2 shows a cross-section of a gap structure filled with a layer on a substrate according to a specific example.

A metal layer may be required as a conductive layer in a semiconductor device. The gap generated during the manufacturing process of the features of the integrated circuit device may be filled with a metal layer. These gaps can have a high aspect ratio because their depth is much larger than their width.

The gaps may extend vertically in a layer that is manufactured with a substantially horizontal top surface. The vertical and metal-filled gap can be used, for example, in a word line of a dynamic random access memory (DRAM) type memory volume circuit. The gaps that are vertical and filled with metal can also be used, for example, in logic integrated circuits. For example, metal-filled gaps can be used as gate fills in P-type metal-oxide-semiconductor (PMOS) or complementary metal-oxide-semiconductor (CMOS) integrated circuits or in source / drain trench contacts.

These gaps can also be arranged in the manufactured layers in the horizontal direction. In addition, these gaps can have a high aspect ratio, because of their depth, now in the horizontal direction, much larger than their width. The gap filled with metal in the horizontal direction can be used, for example, in a word line of a 3D NAND type memory volume circuit. These gaps can also be arranged in a combination of vertical and horizontal directions.

The surface of the gap may contain one type of deposition material. Alternatively, the surface of the gap may contain different kinds of deposition materials. The surface of the gap may, for example, comprise alumina and / or titanium nitride. When, for example, a molybdenum conductive layer may be required in the gap, it may be difficult to deposit molybdenum on a different material in the gap. It may be required that the molybdenum layer can cover the entire surface of the gap and fill the entire gap. In addition, it may be required that the molybdenum layer can cover all surfaces including gaps of different kinds of materials.

To fill the entire gap, a seed layer may be deposited in the gap and a body layer may be deposited on the seed layer. The seed layer may be formed by sequentially repeating a pretreatment atomic layer deposition (ALD) cycle. or, The seed layer may be formed by a chemical vapor deposition (CVD) process. The CVD process may be pulsed, where the first precursor is supplied to the substrate in pulses while the first reactant is continuously supplied to the substrate, or vice versa. The host layer can be deposited on the seed layer by sequentially repeating the host ALD cycle. Alternatively, the host layer may be deposited on the seed layer by a CVD process. The CVD procedure may be pulsed, where the second precursor is supplied to the substrate in a pulse while the second reactant is continuously supplied to the substrate, or vice versa.

1a and 1b show a flowchart illustrating a method of depositing a layer according to a specific example, in which a seed layer can be deposited in a gap and a main layer can be deposited on the seed layer. The pre-processing ALD cycle 1 regarding the seed layer may be as shown in FIG. 1 a and the main ALD cycle 2 regarding the body layer may be as shown in FIG. 1 b.

After the substrate with the gap is provided in the reaction chamber in step 3, the first precursor containing metal and halogen atoms may be supplied to the substrate in step 5 for the first supply period T1 (see FIG. 1a). Subsequently, by removing, for example, purifying, a part of the first precursor from the reaction chamber in step 7, for a first removal period R1, the additional supply of the first precursor to the substrate can be stopped. In addition, the cycle may include supplying the first reactant 9 to the substrate for a second supply period T2. The first precursor and a portion of the first reactant may react to form at least a portion of a seed layer on the substrate. Generally, it can take several (about 50) cycles before the seed layer deposition begins. For example, by removing from the reaction chamber in step 11, for example, purifying a part of the first reactant, the second removal period R1 is continued, and the other supply of the first reactant to the substrate is stopped.

The first precursor and the first reactant can be selected to have proper nucleation on the surface of the gap. The pretreatment ALD cycle 1 can be repeated N times to deposit the seed layer, where N is selected between 100 and 1000, preferably between 200 and 800, and more preferably between 300 and 600. The seed layer may have a thickness between 1 and 20 nm, preferably between 2 and 10 nm, and more preferably between 3 and 7 nm.

After pretreatment, the ALD cycle 1 was repeated N times. The second precursor containing metal and halogen atoms can be supplied to the substrate by the main body ALD cycle 2 in step 11, while the third supply is continued Segment T3 (see Figure 1b). This can be done in the same reaction chamber as the pre-treatment ALD cycle 1 of FIG. 1a or in a different reaction chamber. When the temperature requirements regarding the pretreatment cycle may be different, it may be advantageous to perform a bulk ALD cycle in a reaction chamber different from the pretreatment ALD cycle. Therefore, substrate transfer may be necessary. Subsequently, for example, by removing from the reaction chamber in step 13, for example, purifying a part of the second precursor, and continuing the third removal period R3, the additional supply of the second precursor to the substrate can be stopped.

In addition, the cycle may include supplying the second reactant 15 to the substrate for a fourth supply period T4. The second precursor and a part of the second reactant may react to form at least a part of the host layer on the substrate. For example, by removing from the reaction chamber in step 17, for example, purifying a part of the second reactant for a fourth removal period R4, the additional supply of the second reactant to the substrate is stopped. The second precursor and the second reactant may be selected to have appropriate electronic characteristics. For example, to have a low resistivity. Molybdenum films can have resistivities below 3000 μΩ-cm, or below 1000 μΩ-cm, or below 500 μΩ-cm, or below 200 μΩ-cm, or below 100 μΩ-cm, or below 50 μΩ-cm, or Below 25 μΩ-cm, or below 15 μΩ-cm or even below 10 μΩ-cm.

The main body ALD cycle 2 of the main body layer can be repeated M times, where M selection is between 200 and 2000, preferably between 400 and 1200, and more preferably between 600 and 1000. The host layer may have a thickness between 1 and 100 nm, preferably between 5 and 50 nm, and more preferably between 10 and 30 nm.

The first and second precursors may include the same metal atom. The metal may be a transition metal atom. The transition metal atom may be molybdenum.

The first and second precursors may include the same halogen atom. The halogen atom may be chlorine. By having the same halogen, the inspection of tools and procedures in the fab can be simplified because only one halogen needs to be evaluated. The first precursor may include molybdenum pentachloride (MoCl ₅ ).

During the pretreatment ALD cycle, the processing temperature in the reaction chamber can be selected between 300 and 800 ° C, preferably between 400 and 700 ° C and more preferably between 450 and 550 ° C. The container that vaporizes the first precursor can be maintained between 40 and 100 ° C, preferably between 60 and 80 ° C and more preferably at about 70 ° C.

The second precursor may include another atom that is not a metal or halogen atom. The additional atom may be a chalcogen. The chalcogen can be oxygen, sulfur, selenium or tellurium. The second precursor may include molybdenum (VI) dichloride (MoO ₂ Cl ₂ ).

During the bulk ALD cycle, the processing temperature may be between 300 and 800 ° C, preferably between 400 and 700 ° C and more preferably between 500 and 650 ° C. The container for vaporizing the second precursor can be maintained between 20 and 150 ° C, preferably between 30 and 120 ° C and more preferably between 40 and 110 ° C.

Supplying the first and / or second precursor into the reaction chamber may take a duration T1, selected between 0.1 and 10 seconds, preferably between 0.5 and 5 seconds, and more preferably between 0.8 and 2 seconds T3. For example, T1 may be 1 second and T3 may be 1.3 seconds. The flow rate of the first or second precursor in the reaction chamber can be selected between 50 and 1000 sccm, preferably between 100 and 500 sccm, and more preferably between 200 and 400 sccm. The pressure in the reaction chamber can be selected between 0.1 and 100 Torr, preferably between 1 and 50 Torr, and more preferably between 4 and 20 Torr.

One or both of the first and second reactants may have a hydrogen atom. At least one of the first and second reactants may include hydrogen (H ₂ ). The first and second reactants can be the same. The duration T2, T4 of supplying the first and / or second reactant to the reaction chamber may take between 0.5 and 50 seconds, preferably between 1 and 10 seconds, and more preferably between 2 and 8 seconds between. The flow rate of the first or second reactants in the reaction chamber may be between 50 and 50,000 sccm, preferably between 100 and 20,000 sccm, and more preferably between 500 and 10,000 sccm.

Silane can be considered as the first and / or second reactant. The general formula of silane is Si _x H2 _{(x + 2)} , where x is an integer of 1, 2, 3, 4, ... silane (SiH ₄ ), disilane (Si ₂ H ₆ ), or trisilane (Si ₃ H ₈ ) May be a suitable example of the first and or second reactant having a hydrogen atom.

Remove from the reaction chamber, for example, purify at least one of the first precursor, the first reactant, the second precursor, and the second reactant. The duration R1, R2, R3, or R4 can be between 0.5 and 50 seconds. Time, preferably between 1 and 10, and more preferably between 2 and 8 seconds. Purification can be used before the first After the precursor is supplied to the substrate; after the first reactant is supplied to the substrate; after the second precursor is supplied to the seed layer; and after the second reactant is supplied to the seed layer, the first reactant is removed from the reaction chamber A precursor, a first reactant, a second precursor, and at least one of the second reactants have a duration of R1, R2, R3, or R4. Removal can be achieved by pumping and / or by providing purge gas. The purge gas may be an inert gas, such as nitrogen.

This method can be used in single or batch wafer ALD equipment. The method includes providing a substrate in a reaction chamber and a pre-treatment ALD cycle in the reaction chamber may include: supplying a first precursor to the substrate in the reaction chamber; purifying a portion of the first precursor from the reaction chamber; and The first reactant is supplied on a substrate in the reaction chamber; and a part of the first reactant is purified from the reaction chamber. In addition, the method includes providing a substrate in the reaction chamber and subjecting the body to ALD in the reaction chamber including: supplying a second precursor to the substrate in the reaction chamber; purifying a portion of the second precursor from the reaction chamber; and The second reactant is supplied to the substrate in the reaction chamber; and a part of the second reactant is purified from the reaction chamber.

Exemplary single-wafer reactors specifically designed for performing ALD procedures are available under the trade names Pulsar®, Emerald®, Dragon®, and Eagle® from ASM International NV (Almere, The Netherlands). This method can also be performed in a batch wafer reactor, such as a vertical furnace. For example, the deposition process can be performed in an A412 ^™ vertical furnace, also purchased from ASM International NV. The furnace may have a processing chamber capable of holding 150 semiconductor substrate or wafer loads with a diameter of 300 mm.

The wafer reactor can be provided with a controller and a memory that can control the reactor. When the memory can be programmed to execute on the controller, the precursor and the reactant are supplied into the reaction chamber according to a specific example of the present invention.

FIG. 2 shows a cross-section of a gap structure filled with a layer on a substrate according to a specific example of the present invention. As shown, the gap may extend vertically and horizontally in a layer that is manufactured with a substantially horizontal top surface.

These gaps may have a high aspect ratio because the depth in the vertical and / or horizontal direction is much greater than the width. For example, in the vertical direction, the gap has a width of 207 nm at the top, 169 nm in the middle, and 149 nm at the bottom, and the gap has a much larger depth of 432 nm. For example, in the horizontal direction, the first gap has a width of 34 nm from the top, and the depth of the gap is much larger, which is 163 nm (rounded). The aspect ratio (gap depth / gap width) of the gap may be greater than about 2, greater than about 5, greater than about 10, greater than about 20, greater than about 50, greater than about 75, or in some cases even greater than about 100 or greater than about 150 or greater.

It can be noted that the aspect ratio of the gap may be difficult to measure, but in this article, the aspect ratio may be replaced by a surface enhancement ratio, which may be the relative surface area of the gap in the wafer or part of the wafer. The ratio of the flat surface area on a wafer or a portion of a wafer. The surface enhancement ratio (surface gap / surface wafer) of the gap can be greater than about 2, greater than about 5, greater than about 10, greater than about 20, greater than about 50, greater than about 75, or in some cases even greater than about 100 or greater About 150 or more.

The surface of the gap may contain different kinds of deposition materials 19,21. The surface may, for example, contain Al ₂ O ₃ or TiN.

The conformal metal layer 23 is deposited on the surface of the gap by sequentially repeating the pre-treatment ALD cycle with the first precursor to deposit the seed layer and sequentially repeating the main ALD cycle with the second precursor. The details of the method used are shown in Figures 1a and 1b and the related description. In some specific examples, the deposited Mo-containing film may have a step coverage of greater than about 50%, greater than about 80%, greater than about 90%, greater than about 95%, greater than about 98%, greater than about 99%.

The first and second precursors may include the same metal atom, such as a transition metal atom, such as molybdenum. The first and second precursors may contain the same halogen atom, such as chlorine. The first precursor may include MoCl5. The second precursor may include another atom that is not a metal or halogen atom, such as a chalcogen atom, such as oxygen. The second precursor may include molybdenum (VI) dichloride (MoO ₂ Cl ₂ ). This method can be performed in an atomic layer deposition apparatus. For example, these deposition procedures can be performed in an EMERALD® XPALD equipment.

The first and second reactants are hydrogen (H ₂ ), which are supplied into the reaction chamber at a flow rate of 495 sccm for a period of 5 seconds T2 and T4. The purge gas nitrogen is used after supplying the first precursor; after supplying the first reactant; after supplying the second precursor; and after supplying the second reactant, for a duration of 5 seconds R1, R2, R3 or R4.

During the pretreatment and bulk ALD cycles, the processing temperature was about 550 ° C and the pressure was about 10 Torr. The container for vaporizing the first precursor was about 70 ° C. The container for vaporizing the second precursor was about 35 ° C.

A seed layer of about 4.6 nm was deposited using a pretreatment ALD cycle for 500 cycles, and a main layer of about 21.4 nm was deposited using a main ALD cycle for 800 cycles. As shown, the molybdenum layer 23 is deposited very uniformly on the surface of the gap and has a total thickness of about 26 nm.

The orientation of the gap, whether it is horizontal or vertical, and the width of the gap does not appear to substantially affect the thickness of the layer 23. In addition, the surface material, whether it is Al ₂ O ₃ 19 or TiN 21 does not appear to affect the thickness of the layer 23. In this way, it is possible to produce metal-filled gaps with good uniformity.

This method can also be used in space atomic layer deposition equipment. In spatial ALD, precursors and reactants are continuously supplied in different physical sections and the substrate moves between these sections. At least two sections can be provided, in which case a semi-reaction can be performed in the presence of the substrate. If the substrate is present in such a semi-reactive section, a single layer may be formed from the first or second precursor. The substrate is then moved to another half-reaction zone where the ALD cycle is completed using the first or second reactants to form an ALD monolayer. Alternatively, the substrate position may be fixed and the gas supply may be moved, or some combination of the two. In order to obtain a thicker film, this process can be repeated.

According to a specific example of the spatial ALD equipment, the method includes: placing a substrate in a reaction chamber including a plurality of sections, each section being separated from an adjacent section by an air curtain; The first precursor is supplied to the substrate in the first section of the reaction chamber; the substrate surface is moved laterally through the air curtain into the second section of the reaction chamber with respect to the reaction chamber; the first reactant is supplied to the reaction The substrate in the second section of the chamber to form a seed layer; move the substrate surface laterally through the air curtain with respect to the reaction chamber; and repeatedly supply the first precursor and reactants, including the substrate surface with the reaction chamber laterally Ground to form a seed layer.

In order to form the main body layer, the method further includes: placing the substrate in a reaction chamber including a plurality of sections, each section being separated from an adjacent section by an air curtain; and supplying a second precursor to the first section of the reaction chamber. The substrate in one section; the substrate surface is moved laterally through the air curtain into the second section of the reaction chamber with respect to the reaction chamber; the second reactant is supplied to the substrate in the second section of the reaction chamber to Forming the body layer; moving the substrate surface laterally through the air curtain with respect to the reaction chamber; and repeatedly supplying the second precursor and the reactant, including moving the substrate surface laterally with respect to the reaction chamber to form the body layer.

The first and second precursors may be different. The first and second reactants may be the same and include a hydrogen atom.

According to a specific example, the seed layer may be deposited by a chemical vapor deposition (CVD) process, wherein the first precursor and the first reactant system are simultaneously supplied to the substrate. The host layer can be deposited by a CVD process, wherein the second precursor and the second reactant can also be supplied to the substrate at the same time.

The CVD process may be a pulsed CVD process in which the precursor system is supplied to the substrate in pulses while the reactants are continuously supplied to the substrate. The advantage can be that higher concentrations of reactants can reduce the concentration of halogens. High concentrations of halogen may damage semiconductor devices on the substrate.

For example, in a pulsed CVD process for a seed layer, the first precursor Molybdenum chloride (MoCl5) can be alternately provided with a pulse of 1 second and a flow rate of flushing gas of 5 seconds. The first reactant hydrogen can be continuously supplied at a flow rate of 500 sccm and the substrate can be maintained at 550 ° C.

An exemplary single-wafer reactor specifically designed to perform CVD procedures is available under the trade name Dragon® from ASM International NV (Almere, The Netherlands). This method can also be performed in a batch wafer reactor, such as a vertical furnace. For example, the deposition process can be performed in an A400 ^TM or A412 ^TM vertical furnace, also purchased from ASM International NV. The furnace may have a processing chamber capable of holding 150 semiconductor substrate or wafer loads.

For manufacturing 3D NAND memory, the word lines may have gaps that require low resistivity metal fill. Existing solutions can utilize TiN as a seed layer for CVD tungsten gap filling. For current fluorine-based tungsten deposition procedures, fluorine from the WF6 precursor can diffuse. A thicker (= 3nm) TiN barrier layer may be necessary to prevent fluorine diffusion and diffusing fluorine from attacking high-k Al2O3 films. However, the high resistivity of the tin film (800 μΩ-cm at 3 nm) leads to an increase in the resistivity of the TiN / W stack, which may be undesirable.

There may be a need for an improved method of forming a deposited layer on a substrate having a low resistivity while not containing fluorine. Therefore, a method of forming a layer can be provided, the method comprising: providing a substrate having gaps which are generated during a feature manufacturing process; depositing a seed layer on the substrate; and depositing a body layer on the seed layer . Depositing the host layer may include supplying a second precursor including a transition metal such as tungsten to deposit the host layer on top of the seed layer.

The second precursor may contain a halogen, such as chlorine, to deposit a host layer. The second precursor may be tungsten (V) (WCl ₅ ) or tungsten (VI) hexachloride (WCl ₆ ). The host layer may be deposited by reacting tungsten (V) (WCl ₅ ) or tungsten (VI) hexachloride (WCl ₆ ) with hydrogen H ₂ in an ALD or CVD operation mode. For example, the reaction of WCl ₅ can be achieved at a temperature of 450 ° C and a pressure of 40 Torr. Such precursors can be provided in ALD or CVD modes of operation.

The seed layer may be deposited by reacting a first precursor including molybdenum with hydrogen. The resistivity of the seed layer using molybdenum can be 107 μΩ-cm (3 nm), which is smaller than that of the TiN layer. Especially for 15nm stack thickness (equivalent to gap filling in a 30nm CD structure), use this method to achieve good gap filling. By using tungsten (V) (WCl ₅ ) or tungsten (VI) hexachloride (VI) (WCl ₆ ) to deposit a bulk layer on top of the seed layer, it is possible to deposit a tungsten layer without using fluorine and still have Low resistivity. The seed layer precursor may include a transition metal (such as molybdenum (Mo)), a halogen (such as chlorine (Cl)), and optionally a chalcogen atom (such as oxygen (O)). The seed layer precursor may be, for example, pentachloride (MoCl ₅ ) or molybdenum (VI) dichloride (MoO ₂ Cl ₂ ), both of which react with hydrogen. If molybdenum pentachloride (MoCl ₅ ) is used together with molybdenum dichloride (MoO ₂ Cl ₂ ), the partial pressure of hydrogen can be reduced by 100 times.

The deposition rate of the molybdenum seed layer can be 1.2 Angstroms per cycle. For comparison, the deposition rate of the TiN seed layer can be 0.6 Angstroms per cycle under the same conditions. The deposition rate of the molybdenum seed layer may thus be sufficient.

The metal deposited on the seed layer may be copper. The second precursor may include copper. The second precursor may contain a halogen, such as chlorine, to deposit a host layer. The second precursor may include copper (II) dichloride (CuCl ₂ ) or cuprous chloride (CuCl). The precursors can be provided in an ALD or CVD mode of operation that reacts with hydrogen.

The metals deposited on the seed layer can be transition metals or precious metals from the following groups: Ti, V, Cr, Mn, Nb, Mo, Ru, Rh, Pd, Ag, Hf, Ta, W, Re, Os, Ir And Pt. In some specific examples, the layer may include Co or Ni.

In other specific examples, the seed or host layer may contain less than about 40 atomic%, less than about 30 atomic%, less than about 20 atomic%, less than about 10 atomic%, less than about 5 atomic%, or even less than about 2 atomic% oxygen. In other specific examples, the seed or host layer may contain less than about 30 atomic%, less than about 20 atomic%, less than about 10 atomic% or less than about 5 atomic%, or less than about 2 atomic%, or even less than about 1 atomic% hydrogen. In some specific examples, the seed or host layer may contain less than about 10 atomic%, or less than about 5 atomic%, less than about 1 atomic%, or even less than about 0.5 atomic% of a halogen atom or chlorine. In yet other specific examples, the seed or host layer may contain less than about 10 atomic%, or less than about 5 atomic%, or less than about 2 atomic%, or less At about 1 atomic%, or even less than about 0.5 atomic% carbon. In the specific examples outlined herein, the atomic percentage (atomic%) concentration of an element can be measured using Rutherford backscattering (RBS).

In some specific examples of the present invention, forming a semiconductor device structure, such as a semiconductor device structure, may include forming a gate electrode structure including a molybdenum film, the gate electrode structure having an effective work function greater than about 4.9 eV, or greater than about 5.0 eV , Or greater than about 5.1 eV, or greater than about 5.2 eV, or greater than about 5.3 eV, or even greater than about 5.4 eV. In some specific examples, the effective work function value provided above may be demonstrated by an electrode structure including a molybdenum film having a thickness of less than about 100 Angstroms, or less than about 50 Angstroms, or less than about 40 Angstroms, or even less than about 30 Angstroms.

Those skilled in the art will understand that various omissions, additions, and modifications to the above procedures and structures can be made without departing from the scope of the present invention. Various combinations or sub-combinations of the specific features and aspects of the specific examples are contemplated and are still within the scope of the description. Various features and aspects of the specific examples disclosed may be sequentially combined with each other or replaced. All such modifications and variations are intended to fall within the scope of the invention as defined by the scope of the accompanying patent application.

Claims (28)

A method of forming a layer, comprising: providing a substrate having gaps, the gaps being generated during a feature manufacturing process; depositing a sub-layer on the substrate; and depositing a main layer on the seed layer Wherein, depositing the seed layer includes: supplying a first precursor including a metal and a halogen atom to the substrate; and supplying a first reactant to the substrate, wherein the first precursor and the first reactant A portion of the reaction forms at least a portion of the seed layer; wherein depositing the host layer includes: supplying a second precursor including a metal and a halogen atom to the seed layer; and supplying a second reactant to the seed layer, wherein the first Two precursors and one of the second reactants partially react to form at least a portion of the host layer on the seed layer, and wherein the first and second precursor systems are different. The method of claim 1, wherein at least one of the first and second reactants comprises a hydrogen atom. The method of claim 2, wherein at least one of the first and second reactants comprises hydrogen (H ₂ ). The method of claim 1, wherein the first and second precursors include the same metal atom. The method of claim 1, wherein at least one of the first and second precursors includes a transition metal atom. The method of claim 5, wherein the transition metal atom is molybdenum. The method of claim 1, wherein the first and second precursors contain the same halogenogen child. The method of claim 1, wherein the halogen atom is chlorine. The method of claim 1, wherein the first precursor comprises molybdenum pentachloride (MoCl ₅ ). The method of claim 1, wherein the second precursor includes another atom that is not a metal or halogen atom. The method of claim 10, wherein the additional atom is a chalcogen atom. The method according to claim 11, wherein the chalcogen atom is oxygen. The method of claim 12, wherein the second precursor comprises molybdenum (VI) dichloride (MoO ₂ Cl ₂ ). The method of claim 1, wherein at least one of the first and second precursors is supplied to the reaction chamber in pulses and the pulses are between 0.1 and 10 seconds. The method of claim 1, wherein the flow rate of the first or second precursor into the reaction chamber is between 50 and 1000 sccm. The method of claim 1, wherein the flow rate of the first or second reactant into the reaction chamber is between 50 and 50,000 sccm. The method of claim 1, wherein the pressure in the reaction chamber is between 0.1 and 100 Torr. The method of claim 1, wherein the processing temperature is between 300 and 800 ° C. The method of claim 1, wherein depositing at least one of the seed and the host layer includes repeating an atomic layer deposition (ALD) cycle including sequentially supplying the first or second precursor to the substrate; and the first Or a second reactant is supplied to the substrate. The method of claim 19, wherein the substrate is purified between 0.5 and 50 seconds before the first precursor, the first reactant, the second precursor, or the second reactant is supplied to the substrate. Time between. The method of claim 19, wherein supplying the first and / or second reactant to the reaction chamber takes a time between 0.5 and 50 seconds. The method of claim 19, wherein for depositing the seed layer, the pretreatment ALD cycle is repeated a number of times between 100 and 1000 times, and for depositing the main layer, the main ALD cycle is repeated between 200 and 2000 times Times. The method of claim 1, wherein depositing at least one of the seed and the host layer includes a chemical vapor deposition (CVD) process, wherein the precursor system and the reactant are simultaneously supplied to the substrate. The method according to claim 5, wherein the transition metal atom is tungsten (W). The method of claim 1, wherein the second precursor includes tungsten (W). The method of claim 25, wherein the second precursor comprises tungsten (V) (WCl ₅ ) or tungsten (VI) hexachloride (WCl ₆ ). The method of claim 1, wherein the second precursor comprises copper. The method of claim 24, wherein the second precursor comprises copper (II) chloride (CuCl ₂ ) or cuprous chloride (CuCl).