KR20220155951A - Layer forming method - Google Patents

Abstract

Provided is a method for forming a layer which comprises the following steps of: depositing a seed layer on a substrate; and depositing a bulk layer on the seed layer. The step of depositing the seed layer comprises the following steps of: supplying a first precursor containing metal and halogen atoms to the substrate; and supplying a first reactant to the substrate. The step of depositing the bulk layer comprises the following steps of: supplying a second precursor containing metal and halogen atoms to the seed layer; and supplying a second reactant to the seed layer.

Description

Layer forming method {LAYER FORMING METHOD}

Cross references to related patent applications

This application is a continuation-in-part of US Non-Application Serial No. 15/691,241, filed on August 30, 2017, entitled "Layer Formation Method", filed on December 18, 2017, and entitled "Layer Formation Method". Priority is claimed from US provisional application Ser. No. 62/607,070, both patents incorporated herein by reference.

technology field

The present disclosure generally relates to a method of forming a layer on a substrate. In particular, the present disclosure relates to sequentially repeating atomic layer deposition (ALD) cycles or chemical vapor deposition (CVD) processes to form at least a portion of a layer on a substrate having gaps created during feature fabrication. The layer on the substrate can be used in the manufacture of semiconductor devices.

In atomic layer deposition (ALD) and chemical vapor deposition (CVD), a substrate is given a first precursor and a first reactant suitable for reacting into a desired layer on the substrate. A layer may be deposited within a gap created during fabrication of a feature on the substrate to fill the gap.

In ALD, a substrate is exposed to a pulse of a first precursor, and a monolayer of the first precursor may be chemisorbed onto the surface of the substrate. The surface area may be occupied entirely or by division of the first precursor. Since the first precursor does not adsorb or react with portions of the first precursor already adsorbed on the substrate surface, the reaction may be chemically self-limiting. The excess of the first precursor is then purged, for example by providing an inert gas and/or removing the first precursor from the reaction chamber. Sequentially, the substrate is exposed to a first reactant pulse, which reacts with all or a fraction of the adsorbed first precursor to finally complete the reaction and cover the surface with a monolayer of the reactant.

It has been discovered that there may be a need to improve the quality of the deposited layer.

There may be a need for an improved method for forming a deposition layer on a substrate. Accordingly, a method of forming a layer may be provided, comprising providing a substrate having a gap created during fabrication of a feature and depositing a seed layer on the substrate; and depositing a bulk layer on the seed layer. Depositing the seed layer may include supplying a first precursor containing metal and halogen atoms to the substrate; and supplying a first reactant to the substrate, wherein the first reactant and a portion of the first precursor react to form at least a portion of the seed layer. Depositing the bulk layer may include supplying a second precursor containing metal and halogen atoms to the seed layer; and supplying a second reactant to the substrate, wherein the second reactant and a portion of the second precursor react to form at least a portion of the bulk layer. The first precursor and the second precursor may be different.

By having different first and second precursors for the seed and bulk layers, the properties of the seed and bulk layers can be optimized so that the quality of the entire layer can be improved. The first reactant and the second reactant may be the same and may include a hydrogen atom.

In some other implementations, a semiconductor processing method is provided. The method includes filling the gap in the substrate by depositing a metal layer into the gap.

These and other features, aspects and advantages of the invention disclosed herein will be described below with reference to drawings of specific embodiments, which illustrate the invention and are not intended to limit it.
1A and 1B present a flow diagram illustrating a method of depositing a layer according to one implementation.
2 shows a cross-section of a gap structure on a substrate filled with layers according to one embodiment.

A metal layer may be required as a conductive layer of a semiconductor device. Gaps created during feature fabrication of integrated circuit devices may be filled with metal layers. A gap can have a high aspect ratio because its depth is much greater than its width.

The gap may extend vertically in an already prepared layer having a substantially horizontal top surface. Vertical gaps filled with metal may be used, for example, in word lines of memory integrated circuits of the dynamic random access memory (DRAM) type. Vertical gaps filled with metal can also be used, for example, in logic integrated circuits. For example, the metal filled gap may be used as a gate fill in a P-type metal oxide semiconductor (PMOS) or complementary metal oxide semiconductor (CMOS) integrated circuit or source/drain trench contact.

The gaps can also be arranged in a horizontal direction in an already manufactured layer. Also, the gap can have a high aspect ratio because its depth is much greater than its width in the current horizontal direction. The metal-filled gap in the horizontal direction can be used, for example, in a word line of a 3D NAND type memory integrated circuit. Gaps can also be arranged in a combination of vertical and horizontal directions.

The surface of the gap may contain some kind of deposition material. Alternatively, the surface of the gap may include a different type of deposition material. The surface of the gap may include, for example, aluminum oxide and/or titanium nitride. For example, where a molybdenum conducting layer may be required in the gap, it may be difficult to deposit molybdenum on dissimilar materials within the gap. A molybdenum layer may be required to cover the entire surface of the gap and fill the gap completely. It may further be desired that the molybdenum layer be able to cover the entire surface of the gap containing other types of materials.

To fill the complete gap, a seed layer can be deposited in the gap and a bulk layer can be deposited over the seed layer. The seed layer may be formed by sequentially repeating pretreatment atomic layer deposition (ALD) cycles. Alternatively, the seed layer may be formed by a chemical vapor deposition (CVD) process. The CVD process may be pulsed, wherein a first precursor is supplied in pulses to the substrate while a first reactant is supplied continuously or otherwise to the substrate. A bulk layer may be deposited on the seed layer by sequentially repeating the bulk ALD cycle. Alternatively, a bulk layer may be deposited on the seed layer by a CVD process. The CVD process may be pulsed, wherein the second precursor is supplied in pulses to the substrate while the second reactant is supplied continuously or otherwise to the substrate.

1A and 1B present a flow diagram illustrating a method of depositing a layer according to an implementation in which a seed layer may be deposited within the gap and a bulk layer may be deposited over the seed layer. A pretreatment ALD cycle (1) for the seed layer can be shown in FIG. 1A, and a bulk ALD cycle (2) for the bulk layer can be shown in FIG. 1B.

After a substrate having a gap is provided in the reaction chamber in step (3), a first precursor including metal and halogen atoms may be supplied to the substrate during a first supply period (T1) in step (5) (FIG. 1A Reference). Sequentially, additional supply of the first precursor to the substrate may be stopped in step 7 by removing, eg, purging, a portion of the first precursor from the reaction chamber during the first removal period R1. Further, the cycle may include supplying the first reactant to the substrate during the second supply period T2 (step 9). The first reactant and a portion of the first precursor may react to form at least a portion of the seed layer on the substrate. Normally, it may take a few (about 50) cycles before deposition of the seed layer begins. In step 11, additional supply of the first reactant to the substrate may be stopped by removing, eg, purging, a portion of the first reactant from the reaction chamber during the second removal period R1.

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

After pretreatment, ALD cycle 1 is repeated N times. A second precursor including metal and halogen atoms may be supplied to the substrate in step 11 during the third supply period T3 in the bulk ALD cycle 2 (see FIG. 1B ). This may be performed in the same reaction chamber as the pretreatment ALD cycle 1 of FIG. 1A or in a different reaction chamber. When the temperature requirements for the pretreatment cycle may be different, it may be advantageous to perform the bulk ALD cycle in a different reaction chamber than the pretreatment ALD cycle. Substrate movement may therefore be necessary. Sequentially, additional supply of the second precursor to the substrate may be stopped by removing, eg, purging, a portion of the second precursor from the reaction chamber during the third removal period R3 in step 13 .

The cycle may further include a step 15 of supplying a second reactant to the substrate during a fourth supply period T4. A portion of the second precursor and second reactant may react to form at least a portion of a bulk layer on the substrate. Additional supply of the second reactant to the substrate may be stopped in step 17 by removing, eg, purging, a portion of the second reactant from the reaction chamber during the fourth removal period R4 . The second precursor and second reactant may be selected to have suitable electronic properties, such as low electrical resistivity. The molybdenum film is less than 3000 μΩ-cm, or less than 1000 μΩ-cm, or less than 500 μΩ-cm, or less than 200 μΩ-cm, or less than 100 μΩ-cm, or less than 50 μΩ-cm, or less than 25 μΩ-cm, or an electrical resistivity of less than 15 μΩ-cm or even less than 10 μΩ-cm.

The bulk ALD cycle (2) for the bulk layer may be repeated M times with M selected from 200 to 2000, preferably 400 to 1200, more preferably 600 to 1000. The bulk layer may have a thickness of 1 to 100, preferably 5 to 50, more preferably 10 to 30 nm.

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

The first precursor and the second precursor may include the same halogen atom. A halogen atom can be a chloride. Having the same halogen can simplify tool and process qualification in the fab as only one halogen may need to be accessed. The first precursor may include molybdenum pentachloride (MoCl ₅ ).

The process temperature in the reaction chamber may be selected between 300 and 800, preferably between 400 and 700, more preferably between 450 and 550° C. during the pretreatment ALD cycle. The vessel in which the first precursor is vaporized may be maintained at 40 to 100° C., preferably 60 to 80° C., more preferably about 70° C.

The second precursor may include additional atoms other than metal or halogen atoms. The additional atom may be a chalcogen. The chalcogen can be oxygen, sulfur, selenium, or tellurium. The second precursor may include molybdenum (VI) dichloride dioxide (MoO ₂ Cl ₂ ).

The process temperature may be 300 to 800, preferably 400 to 700, more preferably 500 to 650 °C during the bulk ALD cycle. The container in which the second precursor is vaporized may be maintained at 20 to 150° C., preferably 30 to 120° C., and more preferably about 40° C. to 110° C.

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

One or both of the first reactant and the second reactant may have a hydrogen atom. At least one of the first reactant and the second reactant may include hydrogen (H ₂ ). The first reactant and the second reactant may be the same. Feeding the first reactant and/or the second reactant to the reaction chamber may take a duration T2, T4 selected from 0.5 to 50, preferably 1 to 10, more preferably 2 to 8 seconds. The flow rate of the first reactant or the second reactant into the reaction chamber may be 50 to 50000 sccm, preferably 100 to 20000 sccm, and more preferably 500 to 10000 sccm.

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

The period R1, R2, R3 or R4 for removing, for example purging, a portion of at least one of the first precursor, first reactant, second precursor and second reactant from the reaction chamber is from 0.5 to 50, preferably from 1 to 10 , more preferably between 2 and 8 seconds. Purging is performed after supplying the first precursor to the substrate, supplying the first reactant to the substrate, supplying the second precursor to the seed layer, and among the first precursor, the first reactant, the second precursor, and the second reactant. It may be used after supplying the second reactant to the seed layer to remove a portion of at least one from the reaction chamber during the period R1, R2, R3 or R4. Removal may be accomplished by pumping and/or providing a purge gas. The purge gas may be an inert gas such as nitrogen.

The method can be used in single or batch wafer ALD equipment. The method comprising providing a substrate in a reaction chamber and a pretreatment ALD cycle in the reaction chamber includes supplying a first precursor to the substrate in the reaction chamber; purging a portion of the first precursor from the reaction chamber; supplying the first reactant to the substrate in the reaction chamber; and purging a portion of the first reactant from the reaction chamber. The method also comprising providing the substrate in a reaction chamber and a bulk ALD cycle in the reaction chamber includes supplying a second precursor to the substrate in the reaction chamber; purging a portion of the second precursor from the reaction chamber; supplying the second reactant to the substrate in the reaction chamber; and purging a portion of the second reactant from the reaction chamber.

Exemplary single wafer reactors specifically designed to perform ALD processes are commercially available from ASM International NV of Almere, The Netherlands under the tradenames Pulsar®, Emerald®, Dragon®, and Eagle®. The method can also be performed in a batch wafer reactor, eg a vertical furnace. For example, the deposition process can be performed in an A412 ^TM vertical furnace available from ASM International NV. This furnace has a process chamber that can accommodate 150 semiconductor substrates, or wafers, with a diameter of 300 mm.

The wafer reactor may be provided with a controller and a memory capable of controlling the reactor. The memory may be programmed with a program that, when executed on the controller, supplies precursors and reactants in the reaction chamber according to embodiments of the present disclosure.

2 shows a cross-section of a gap structure on a layer-filled substrate according to one embodiment of the present disclosure. As can be seen the gap can extend vertically in an already prepared layer having a substantially horizontal top surface.

A gap can have a high aspect ratio because its depth is much greater than its width in the vertical or vertical direction. For example, in the vertical direction, the gap has a width of 207 nm at the top, 169 nm at the middle and 149 nm at the bottom, while the depth of the gap is much larger at 432 nm. For example, in the horizontal direction, the first gap from the top has a width of 34 nm, and the depth of the gap is even greater at 163 nm (rounded). wherein the aspect ratio of the gap (gap depth/gap width) is 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 greater than about 100 or greater than about 150 or greater than about 200; can

An aspect ratio can be difficult to determine for a gap, but in this context aspect ratio is replaced by a surface enhancement ratio, which may be the ratio of the total surface area of a gap in a wafer or wafer portion to the planar surface area of the wafer or wafer portion. can be described as possible. The surface enhancement ratio of the gap (surface gap/surface wafer) is 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 greater than about 100 or greater than about 150 or about 200 may be excessive.

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

A conformal metal layer 23 is deposited on the surface of the gap by depositing a seed layer by sequentially repeating a pretreatment ALD cycle with a first precursor and depositing a bulk layer by sequentially repeating a bulk ALD cycle with a second precursor. do. Details of the method used appear in FIGS. 1A and 1B and associated description. In some embodiments, the deposited film including Mo may have a step coverage 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 precursor and the second precursor may include the same metal atom, for example, a transition metal atom such as molybdenum. The first precursor and the second precursor may include the same halogen atom, for example chloride. The first precursor may include MoCl5. The second precursor may include an additional atom other than a metal or halogen atom, for example a chalcogenide such as oxygen. The second precursor may include molybdenum (VI) dichloride dioxide (MoO ₂ Cl ₂ ). The method may be performed in an atomic layer deposition apparatus. For example, the deposition process can be performed on an EMERALD® XP ALD device.

The first and second reactants were hydrogen (H ₂ ) and were supplied into the reaction chamber at a flow rate of 495 sccm for durations T2 and T4 of 5 seconds. A nitrogen purge gas was used after feeding the first precursor, after feeding the first reactant, after feeding the second precursor, and after feeding the second reactant for a duration of 5 seconds R1, R2, R3, or R4 .

During the pretreatment and bulk ALD cycles, the process temperature was about 550° C. and the pressure was about 10 Torr. The container in which the first precursor was vaporized was about 70°C. The container in which the second precursor was vaporized was about 35°C.

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

The direction of the gap (whether horizontal or vertical) and the width of the gap do not appear to substantially affect the thickness of layer 23 . Also, the material of the surface (whether it is Al ₂ O ₃ (19) or TiN (21)) does not appear to affect the thickness of layer 23. In this way it becomes possible to create metal filled gaps with good uniformity.

The method can also be used in a spatial atomic layer deposition apparatus. In spatial ALD, precursors and reactants are supplied sequentially in different physical sections, and the substrate moves between sections. In the presence of the substrate, at least two sections can be provided in which a half-reaction can occur. If the substrate is in this half reaction section, a monolayer may be formed from either the first precursor or the second precursor. The substrate is then moved to the second half reaction zone, where the ALD cycle is completed with either the first reactant or the second reactant to form one ALD monolayer. Alternatively, the substrate position can be fixed and the gas source can be moved or a combination of the two. This sequence can be repeated to obtain thicker films.

According to one embodiment in a spatial ALD device, the method comprises:

positioning the substrate in a reaction chamber comprising a plurality of sections, each section separated from proximate sections by a gas curtain;

supplying the first precursor to the substrate in a first section of the reaction chamber;

laterally moving the substrate surface relative to the reaction chamber into a second section of the reaction chamber through a gas curtain;

supplying the first reactant to the substrate in the second section of the reaction chamber to form the seed layer;

laterally moving the substrate surface relative to the reaction chamber through a gas curtain; and

and repeating supplying the reactant and the first precursor comprising lateral movement of the substrate surface relative to the reaction chamber to form the seed layer.

To form the bulk layer, the method,

positioning the substrate in a reaction chamber comprising a plurality of sections, each section separated from proximate sections by a gas curtain;

supplying the second precursor to the substrate in the first section of the reaction chamber;

laterally moving the substrate surface relative to the reaction chamber into a second section of the reaction chamber through a gas curtain;

supplying the second reactant to the substrate in the second section of the reaction chamber to form the seed layer;

laterally moving the substrate surface relative to the reaction chamber through a gas curtain; and

and repeating supplying the reactant and the second precursor comprising lateral movement of the substrate surface relative to the reaction chamber to form the bulk layer.

The first precursor and the second precursor may be different. The first reactant and the second reactant may be the same and may include a hydrogen atom.

According to an embodiment, the seed layer may be deposited by a chemical vapor deposition (CVD) process, and the first precursor and the first reactant are simultaneously supplied to the substrate. The bulk layer may be deposited by a CVD process, but the second precursor and the second reactant may be simultaneously supplied to the substrate.

The CVD process may be a pulsed CVD process wherein precursors are pulsed to the substrate while reactants are continuously supplied to the substrate. An advantage may be that higher reactant concentrations may lower halogen concentrations. High concentrations of halogen can damage semiconductor devices on substrates.

For example, in a pulsed CVD process for the seed layer, the first precursor molybdenum pentachloride (MoCl5) may be provided in pulses of 1 second alternating with purge gas flow rates of 5 seconds. The first reactant hydrogen may be continuously supplied at a flow rate of 500 sccm and the substrate may be maintained at 550°C.

An exemplary single wafer reactor specifically designed to perform the CVD process is commercially available from ASM International NV, Almere, The Netherlands, under the trademark Dragon®. The method can also be performed in a batch wafer reactor, eg a vertical furnace. For example, the deposition process may be performed in an A400 ^™ or A412 ^™ vertical furnace available from ASM International NV. This furnace may have a process chamber capable of holding 150 semiconductor substrates, or wafers.

For fabrication of 3D NAND memory, word lines may have gaps that require low resistivity metal filling. Existing solutions may use TiN as a seed layer for CVD tungsten gap filling. In current fluorine-based tungsten deposition processes, fluorine from the WF6 precursor can diffuse. A thick (= 3 nm) TiN barrier may be needed to prevent fluorine diffusion and attack of the high-k Al2O3 film by the diffused fluorine. However, the high resistivity of the TiN film (800 μΩ-cm at 3 nm) results in an undesirable increase in the TiN/W stack resistance.

An improved method for forming deposited layers on substrates having low resistivity in the absence of fluorine may be needed. Accordingly, a method of forming a layer may be provided, comprising providing a substrate having a gap created during fabrication of a feature, depositing a seed layer on the substrate; and depositing a bulk layer on the seed layer. Depositing the bulk layer may include depositing the bulk layer on top of the seed layer by supplying a second precursor including a transition metal such as tungsten.

The second precursor may include a halogen such as chloride to form a bulk layer. The second precursor may be tungsten (V) pentachloride (WCl ₅ ) or tungsten (VI) hexachloride (WCl ₆ ). The bulk layer may be deposited by reaction of tungsten (V) pentachloride (WCl ₅ ) or tungsten (VI) hexachloride (WCl ₆ ) with hydrogen (H ₂ ) in an ALD or CVD mode of operation. For example, the reaction of WCl ₅ may be performed at a temperature of 450° C. and a pressure of 40 Torr. Precursors may be provided in ALD or CVD modes of operation.

The seed layer may be deposited with molybdenum containing a first precursor that reacts with hydrogen. The resistivity of the seed layer using molybdenum is 107 μΩ-cm at a thickness of 3 nm, which is much smaller than that of the TiN layer. Good gap-fill was achieved using this method, especially for stack thicknesses of 15 nm (equivalent to gap-fill in 30 nm CD structures). By using tungsten (V) pentachloride (WCl ₅ ) or tungsten (VI) hexachloride (WCl ₆ ) to deposit a bulk layer on top of the seed layer, a tungsten layer without the use of fluorine and still having a low resistivity It becomes possible to deposit The precursor for the seed layer may include a transition metal (eg, molybdenum (MO)), a halogen (eg, chloride (Cl)), and optionally a chalcogenide (eg, oxygen (O)). The precursor for the seed layer may be, for example, molybdenum pentachloride (MoCl ₅ ) or molybdenum (VI) dichloride dioxide (MoO ₂ Cl ₂ ), both of which react with hydrogen. If molybdenumpentachloride (MoCl ₅ ) is used for molybdenum(VI) dichloride dioxide (MoO ₂ Cl ₂ ), the partial pressure of hydrogen can be 100 times lower.

일 수 있다. 비교를 위해, 동일한 환경 하에서, TiN 씨드층의 증착 속도는 0.6

/사이클일 수 있다. 따라서 몰리브덴 씨드층의 증착 속도는 충분할 수 있다.The deposition rate of the molybdenum seed layer was 1.2 per cycle.

can be For comparison, under the same conditions, the deposition rate of the TiN seed layer is 0.6

/can be a cycle. Therefore, the deposition rate of the molybdenum seed layer may be sufficient.

The metal deposited on the seed layer may be copper. The second precursor may include copper. The second precursor may include a halogen such as chloride to form a bulk layer. The second precursor may include copper (II) chloride (CuCl ₂ ) or copper chloride (CuCl). The precursor may be provided in an ALD or CVD mode of operation in which it reacts with hydrogen.

The metal deposited on the seed layer may be a transition metal or a noble metal from the group of Ti, V, Cr, Mn, Nb, Mo, Ru, Rh, Pd, Ag, Hf, Ta, W, Re, Os, Ir and Pt. have. In some embodiments, the layer can include cobalt (Co) or nickel (Ni).

In additional embodiments, the seed layer or bulk layer contains less than about 40 atomic percent, less than about 30 atomic percent, less than about 20 atomic percent, less than about 10 atomic percent, less than about 5 atomic percent, or less than about 2 atomic percent oxygen. can include In another embodiment, the seed layer or bulk layer has less than about 30 atomic percent, less than about 20 atomic percent, less than about 10 atomic percent, less than about 5 atomic percent, or less than about 2 atomic percent, or even less than 1 atomic percent. May contain hydrogen. In some embodiments, the seed layer or bulk layer can include less than about 10 atomic percent, or less than 5 atomic percent, less than about 1 atomic percent, or even less than 0.5 atomic percent halide or chloride. In yet another embodiment, the seed layer or bulk layer may comprise less than about 10 atomic percent, less than about 5 atomic percent, or less than about 2 atomic percent, or less than about 1 atomic percent, or even less than 0.5 atomic percent carbon. have. In the embodiments outlined herein, atomic percent concentrations of elements can be determined using Rutherford Backscattering (RBS).

미만, 또는 대략 50

미만, 또는 대략 40

미만, 또는 심지어 대략 30

미만의 두께를 갖는 몰리브덴막을 포함하는 전극 구조에서 입증될 수 있다.In some implementations of the present disclosure, forming a semiconductor device structure, such as a semiconductor device structure, is greater than approximately 4.9 eV, greater than approximately 5.0 eV, greater than approximately 5.1 eV, greater than approximately 5.2 eV, forming a gate electrode structure comprising a molybdenum film having an effective work function greater than about 5.3 eV, or even greater than about 5.4 eV. In some embodiments, the effective work function value given above is approximately 100

less than, or about 50

less than, or about 40

less than, or even about 30

It can be demonstrated in an electrode structure comprising a molybdenum film having a thickness of less than

It will be appreciated by those skilled in the art that various omissions, additions and changes may be made to the processes and structures described above without departing from the scope of the present invention. Various combinations or sub-combinations of the specific features and aspects of the embodiments may be made and such combinations are still considered to be within the scope of this disclosure. The various features and aspects of the disclosed embodiments may be combined in any order or substituted for one another. All such modifications and variations are intended to fall within the scope of this invention as defined by the appended claims.

Claims (20)

As a method of forming a layer,
providing a substrate to the reaction chamber;
depositing a first layer on the substrate;
depositing a second layer on the first layer;
Depositing the first layer,
supplying a first precursor containing metal and halogen atoms to the substrate; and
Supplying a first reactant to the substrate;
a portion of the first precursor and the first reactant react to form at least a portion of the first layer;
Depositing the second layer,
supplying a second precursor containing a metal and a halogen; and
supplying a second reactant;
a portion of the second precursor and the second reactant react to form at least a portion of the second layer on the first layer;
At least one of the first reactant or the second reactant includes silane,
wherein the first and second precursors are different. According to claim 1,
wherein the silane is represented by the formula Si _x H _(2x+2) . According to claim 2,
x is an integer greater than or equal to 1 and less than or equal to 4. The method of claim 1 , wherein one of the first reactant and the second reactant comprises hydrogen (H ₂ ). According to claim 1,
The method of claim 1 , wherein the first precursor and the second precursor comprise the same metal atom. According to claim 1,
wherein at least one of the first precursor and the second precursor comprises a transition metal atom. According to claim 5,
The method of claim 1 , wherein the transition metal atom is molybdenum. According to claim 1,
The method of claim 1 , wherein the first precursor and the second precursor comprise the same halogen atom. According to claim 1,
wherein the halogen atom is a chloride. According to claim 1,
wherein the first precursor comprises molybdenumpentachloride (MoCl ₅ ). According to claim 1,
wherein the second precursor comprises an additional atom other than a metal or halogen atom. According to claim 10,
wherein the additional atom is a chalcogenide. According to claim 11,
wherein the chalcogenide is oxygen. According to claim 12,
wherein the second precursor comprises molybdenum(VI) dichloride dioxide (MoO ₂ Cl ₂ ). According to claim 1,
wherein the pressure in the reaction chamber is between 0.1 and 100 torr. According to claim 1,
The process temperature in the reaction chamber is 300 ° C to 800 ° C, the method of forming a layer. According to claim 1,
Depositing the first layer includes repeating an atomic layer deposition (ALD) cycle that sequentially includes supplying the first precursor to the substrate and supplying the first reactant to the substrate. do; and/or
Depositing the second layer includes repeating an atomic layer deposition (ALD) cycle that sequentially includes supplying the second precursor to the substrate and supplying the second reactant to the substrate. To do, how to form a layer. According to claim 1,
wherein depositing at least one of the first layer and the second layer comprises a chemical vapor deposition (CVD) process. According to claim 5,
wherein the transition metal is tungsten (W) or copper (Cu). According to claim 1,
The method of claim 1 , wherein the second precursor comprises tungsten (W) or copper (Cu).

Images