THIN FILM DEPOSITION APPARATUS AND THIN FILM DEPOSITION METHOD

The present invention relates to a thin film deposition apparatus and a thin film deposition method in which the resistivity of a thin film is decreased by reducing the content of impurities inside a thin film. The thin film deposition apparatus may include a process chamber configured to perform a deposition process for causing a first metal and a reactant source to react, to form a thin film on a substrate; a source gas nozzle part configured to supply, into the process chamber, a source gas including the first metal and a ligand; a pretreatment gas nozzle part configured to supply, into the process chamber, a pretreatment gas including a second metal reactable with the ligand; and a reaction gas nozzle part configured to supply, into the process chamber, a reaction gas comprising the reactant source.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to Korean Patent Application No. 10-2019-0124655 filed on Oct. 8, 2019 and all the benefits accruing therefrom under 35 U.S.C. § 119, the contents of which are incorporated by reference in their entirety.

BACKGROUND

The present disclosure relates to a thin film deposition apparatus and a thin film deposition method, and more particularly, to a thin film deposition apparatus and a thin film deposition method, with which the resistivity of a thin film is reduced by reducing impurity concentration in the thin film.

In the semiconductor industries, thin films used for semiconductor devices have been deposited using a method such as an atomic layer deposition (ALD) method or a chemical vapor deposition (CVD) method. At this point, metallic precursor compounds including deposition metals and ligands (or bonding elements) have been mainly used as a source gas for thin film deposition.

In typical arts, when depositing a thin film using a metallic precursor compound, the bond between a deposition metal and a ligand is not effectively disconnected, so that the deposition metal is deposited in a state bonded with a portion of the ligand, and thus, the thin film contains the ligand which may act as impurity, and there is caused a limitation of increasing the resistivity of the thin film.

Recently, as high performance and high integration of semiconductor devices have been required and the sizes of the devices have decreased, a technology for improving the resistivity characteristics of thin films used for semiconductor devices is being demanded.

PRIOR ART DOCUMENT

Patent Document

SUMMARY

The present disclosure provides a thin film deposition apparatus and a thin film deposition method, with which the resistivity of a thin film is reduced by suppressing or preventing intrusion of impurities such as ligands into a thin film while using a source gas including the ligands.

In accordance with an exemplary embodiment, a thin film deposition apparatus includes: a process chamber configured to perform a deposition process for causing a first metal and a reactant source to react, to form a thin film on a substrate; a source gas nozzle part configured to supply, into the process chamber, a source gas including the first metal and a ligand; a pretreatment gas nozzle part configured to supply, into the process chamber, a pretreatment gas including a second metal reactable with the ligand; and a reaction gas nozzle part configured to supply, into the process chamber, a reaction gas including the reactant source.

The reaction gas nozzle part may supply the reaction gas in a manner temporally separate from the source gas and the pretreatment gas.

The pretreatment gas nozzle part may supply the pretreatment gas during at least a portion of a time period when the source gas nozzle part supplies the source gas.

The second metal may have greater bonding energy with the ligand than the first metal.

A supply amount of the pretreatment gas per unit time may be greater than a supply amount of the source gas per unit time.

In accordance with another exemplary embodiment, a thin film deposition method may include: supplying a source gas including a first metal and a ligand into a process chamber to which a substrate is supplied; supplying a pretreatment gas including a second metal reactable with the ligand into the process chamber; and supplying, into the process chamber, a reaction gas including a reactant source which reacts with the first metal and forms a thin film.

The supplying of the source gas and the supplying of the reaction gas may be alternately performed.

The thin film deposition method may further include supplying a purge gas into the process chamber between the supplying of the source gas and the supplying of the reaction gas.

The supplying of the pretreatment gas into the processing chamber may be performed during at least a portion of a time period for supplying of the source gas while performing the supplying the source gas.

The supplying of the pretreatment gas into the process chamber may be performed while supplying a greater supply amount of the pretreatment gas than the source gas.

The supplying of the source gas may be performed for a longer time period than the supplying of the pretreatment gas into the processing chamber.

The supplying of the source gas may be performed for a longer time period than the supplying of the pretreatment gas into the processing chamber.

The second metal may have greater bonding energy with the ligand than the first metal.

In accordance with yet another exemplary embodiment, a thin film deposition method includes: supplying a source gas including titanium (Ti) and a ligand into a process chamber to which a substrate is loaded; supplying a pretreatment gas including silicon (Si) reactable with the ligand into the process chamber; and supplying, into the process chamber, a reaction gas including a nitrogen atom (N) which reacts with titanium (Ti) and forms a titanium nitride (TiN) thin film.

DETAILED DESCRIPTION OF EMBODIMENTS

Hereinafter exemplary embodiments will be described in detail with reference to the accompanying drawings. However, the present invention may, however, be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the present invention to those skilled in the art. In descriptions, like reference numerals refer to like configurations, figures may be partially exaggerated for clarity of illustration of exemplary embodiments, and like reference numerals refer to like elements in figures.

FIG. 1is a cross-sectional view of a thin film deposition apparatus in accordance with an exemplary embodiment andFIG. 2is a horizontal sectional view of a thin film deposition apparatus in accordance with an exemplary embodiment.

Referring toFIGS. 1 and 2, a thin film deposition apparatus100in accordance with an exemplary embodiment may include: a process chamber180configured to perform a deposition process for causing a first metal and a reactant source to react, to form a thin film on a substrate10; a source gas nozzle part111configured to supply a source gas including the first metal and a ligand into the process chamber180; a pretreatment gas nozzle part112configured to supply, into the process chamber180, a pretreatment gas including a second metal reactable with the ligand; and a reaction gas nozzle part113configured to supply, into the process chamber180, a reaction gas including the reactant source.

In the process chamber180, a deposition process may be performed in which the first metal (or transition metal) and the reactant source are caused to react on the substrate10to form a thin film. The process chamber180may be of a single wafer type for processing the substrate10one by one, and of a batch type for stacking a plurality of substrates10on a substrate boat130in a multistage and simultaneously processing the substrates. Here, the first metal may be a deposition metal or a metallic precursor.

For example, in case of the batch type, the process chamber180may be composed of an upper chamber180aand a lower chamber180bwhich communicate with each other, and a reaction tube120for providing a process space, in which the substrate boat130is accommodated and a deposition process may be performed on the substrate10, may be disposed inside the process chamber180. At this point, the reaction tube120may be composed of a single tube or a plurality of tubes, as long as the process space in which the substrate boat130is accommodated and a deposition process may be performed on the substrate10. For example, the reaction tube120may be composed of an outer tube121and an inner tube122. Here, a lower portion of the inner tube122may be connected to and supported on a flange part125, and the structure and shape of the inner tube122are not limited thereto but diversified.

Meanwhile, in the substrate boat130, slots may be formed in multistage on a plurality of rods131so that the substrate10is inserted and loaded. In addition, the substrate boat130may be configured such that an isolation plate (not shown) is disposed on or under the substrate10, and the isolation plate (not shown) is coupled to the plurality of rods131in multistage so that individual processing space may be provided for each substrate10. In addition, the substrate boat130may rotate during a deposition process, and ceramic, quartz, synthetic quartz or the like may be used as the material for the substrate boat130including the isolation plate (not shown), but the shape and material for the substrate boat130are not limited thereto and be diversified.

The source gas nozzle part111may supply, into the process chamber, a source gas including the first metal and the ligand, deposit the first metal (layer) on the substrate10, and deposit a first metal atomic layer (or unit layer) in case of an atomic layer deposition (ALD). Here, the source gas may be a metallic precursor compound, the ligand may be a common name of ions (or atoms) bonded to the first metal in the metallic precursor compound, and be a bonded element bonded with the first metal. Meanwhile, the first metal may include a transition metal such as titanium (Ti), tantalum (Ta), chromium (Cr), zirconium (Zr), tungsten (W), nickel (Ni), copper (Cu), or zinc (Zn), but the embodiment is not limited thereto as long as a metal that may deposit a thin film in a nitride film or an oxide film.

The pretreatment gas nozzle part112may supply, into the process chamber180, a pretreatment gas including a second metal (or metalloid) reactable with the ligand. The second metal may react and bonded with the ligand by supplying the pretreatment gas into the process chamber180through the pretreatment gas nozzle part112, and the second metal is bonded with the ligand and thus the bonding between the first metal and the ligand may be disconnected. Accordingly, the bonding between the first metal and the ligand may be effectively disconnected in the source gas, and the first metal may be suppressed or prevented from being deposited in a state of being bonded with the ligand. Here, the second metal may be a substitute metal and react with the ligand, and include a metalloid such as silicon (Si) and germanium (Ge), but the embodiment is not limited thereto, as long as a metal reactable with the ligand.

The reaction gas nozzle part113may supply a reaction gas including the reactant source into the process chamber180, and cause the reactant source to react with the first metal (layer) on the substrate10to form the thin film (that is, a desired thin film). Here, the reactant source may include a nitrogen (N) atom or an oxygen (O) atom, and the thin film may be a nitride film or an oxide film in which the first metal is nitrified or oxidized.

Such the source gas nozzle part111, the pretreatment gas nozzle part112and the reaction gas nozzle part113may forma gas supply part110. At this point, when the thin film deposition apparatus100is of a batch type, the gas supply part110may be disposed on one side of the inner tube122, and an exhaust duct150may extend in the vertical direction on the other side facing the one side in the inner tube122and may discharge (or remove) residue gas and/or deposition byproducts inside the inner tube122. Meanwhile, the gas supply part110and the exhaust part150are positioned facing each other (or symmetrical to each other), so that a laminar flow may be formed on the substrate10.

FIG. 3is a graph for describing a supply cycle of a source gas, a pretreatment gas, a reaction gas, and an atmosphere gas in accordance with an exemplary embodiment.

Referring toFIG. 3, the reaction gas nozzle part113may supply the reaction gas at a temporally separated time with respect to the source gas and the pretreatment gas. When the reaction gas is supplied together with the pretreatment gas, the second metal included in the pretreatment gas reacts with the reaction gas and thus a byproduct film (that is, undesired thin film) may be formed. In addition, when the reaction gas and the source gas are supplied together, the first metal in the source gas may react with the reactant source before the ligand is disconnected from the source gas, and the thin film may be formed on the first metal in a state of being bonded with the ligand. Accordingly, the ligand is included in the thin film and act as an impurity and the resistivity of the thin film may be increased. In addition, the first metal and the reactant source do not react on the uppermost layer (uppermost surface) on the substrate10, but react in the air above the substrate10, and thus, the coupling power (or, the formed suction force of the substrate with respect to the substrate) between the formed thin film and the substrate10may be weakened.

However, when the reaction gas is supplied at the temporally separated time with respect to the source gas and the pretreatment gas, the second metal may react with the reaction gas and prevent the formation of the byproduct film, and cause only the first metal deposited on the substrate10to react with the reaction gas.

Meanwhile, the thin film may be deposited through a method such as an atomic layer deposition (ALD) method or a chemical vapor deposition (CVD) method, and may be deposited while supplying the reaction gas at a temporally separated time with respect to the source gas and the pretreatment gas.

The pretreatment gas nozzle part112may supply the pretreatment gas during a portion of a time period when the source gas nozzle part111supplies the source gas, and the pretreatment gas may be supplied together with the source gas for a certain time period (or predetermined time period). The pretreatment gas function to separate the first metal and the ligand by disconnecting the bonding between the first metal and the ligand before the first metal is deposited on the substrate10, and therefore the pretreatment gas needs to be supplied together (co-flow) with the source gas. To this end, the pretreatment gas may be supplied during at least a portion of the time period for supplying the source gas. Accordingly, the first metal and the ligand are separated before the first metal is deposited on to the substrate10, so that the first metal deposited in a state of being bonded with the ligand may be minimized.

At this point, the time period for supplying the pretreatment gas may be shorter than the time period for supplying the source gas, and before the source gas and the pretreatment gas are supplied together (co-flow), the first metal may be deposited on the substrate10earlier than the second metal by supplying only the source gas. Accordingly, it is not only possible to cause the second metal not to be deposited on the substrate10but to react with the ligand, but also possible to prevent the second metal from being deposited on the substrate10. That is, the second metal may also be an atom (or matter) that may be deposited on the substrate10. Thus, when the source gas and the pretreatment gas are started to be supplied together, the second metal may be deposited on the substrate10and react with the reaction gas to form the byproduct film. In addition, the second metal is contained in the thin film and act as an impurity.

However, when only the source gas is first supplied for a certain time period (or predetermined time period), it is possible to induce such that the first metal (layer) is first deposited on the substrate10and only the first metal is deposited on the substrate10. In addition, not only the ligand may be suppressed or prevented from being contained in the thin film by causing the second metal to disconnect, through the bonding with the ligand, the bonded ligand from the first metal that has been deposited in a state of being bonded with the ligand, but also the second metal may be prevented from being deposited on the substrate10. Accordingly, the second metal may be induced to react only with the ligand, and the bonding product generated by the reaction (bonding) of the second metal and the ligand may be discharged from the inside (or inside of the inner tube) of the process chamber180.

Meanwhile, the gas supply part110may further include a purge gas nozzle part114configured to supply a purge gas. The purge gas nozzle part114may supply a purge gas, and purge and discharge the residue gas of source gas, the pretreatment gas and/or the reaction gas from the inside of the process chamber180. At this point, the purge gas may include a nitrogen (N2) gas, or an inert gas such as argon (Ar), helium (He) or neon (Ne). In addition, the purge gas nozzle part114may be symmetrically disposed on both sides with the source gas nozzle part111, the pretreatment gas nozzle part112and the reaction gas nozzle part113therebetween, and may adjust the injection range (or area) of each gas (that is, the source gas, the pretreatment gas, and the reaction gas).

In addition, the controlled atmosphere gas illustrated inFIG. 3is a gas for adjusting the atmosphere inside the process chamber180and may adjust the internal pressure of the process chamber180, and a nitrogen (N2) gas or an inert gas such as argon (Ar), helium (He) or neon (Ne) may be used as the atmosphere gas. In addition, in order to carry, into the process chamber180, any one gas among the source gas, the pretreatment gas, or the reaction gas, a carrier gas may be used, and a nitrogen (N2) gas or an inert gas such as argon (Ar), helium (He) or neon (Ne) may be used as the carrier gas corresponding to the atmosphere gas. Here, the carrier gas may be used to carry a vapor-state raw material after vaporizing the liquid-state raw material into a vapor state. Meanwhile, the purge gas may also be determined corresponding to the atmosphere gas.

FIG. 4is a view for describing changes in resistivity according to a time for simultaneously supplying a source gas and a pretreatment gas in accordance with an exemplary embodiment, (a) ofFIG. 4illustrates the supply sequence of a process gas, and (b) ofFIG. 4is a resistivity graph according to a simultaneous supply time of a source gas and a pretreatment gas.

Referring toFIG. 4, titanium tetrachloride (TiCl4) may be used as the source gas, silane SiH4may be used as the pretreatment gas, and ammonia NH3may be used as the reaction gas. At this point, titanium (Ti) as the first metal (or deposition metal) and nitrogen atom (N) as a reactant source, react and form (or deposit) a titanium nitride (TiN) thin film. In addition, silicon (Si) as the second metal may act as a substitute metal and be bonded with a chlorine (Cl) element as a ligand to generate SiClx(e.g. SiCl2), and the bonding between the titanium (Ti) and the chlorine (Cl) element is disconnected, so that the titanium (Ti) may be separated from the chlorine (Cl) element. Here, the substitute metal means a metal which is bonded with the ligand bonded to another metal (atom), disconnects the bond with the another metal, and thereby substitutes (replaces) the metal (atom) or the center atom to which the ligand is bonded. In addition, the SiClxwhich is a bonded product of the silicon (Si), which is the second metal, and the chlorine element (Cl), which is the ligand, may be in a gas phase, and be discharged from the inside of the process chamber through purging and/or exhaust. In addition, hydrogen element (H) bonded to the silicon (Si) which is the second metal may be separated from the silicon (Si) and present in a gas state (that is, H2), or bonded to the chlorine element (Cl) and present as gas-state hydrogen chloride (HCl). At this point, hydrogen (H2) and/or hydrogen chloride (HCl) may also be discharged from the inside of the process chamber180through purging and/or exhaust.

Table 1 illustrates bonding energy between the chlorine element (Cl) and titanium (Ti) and bonding energy between the chlorine element (Cl) and silicon (Si).

Referring toFIG. 4and Table 1, the second metal may have greater bonding energy with the ligand than the first metal. Large bonding energy between each other means that bonding is well established and is not easily disconnected, and small bonding energy means that bonding power is weak and is easily disconnected. In addition, when the bonding energy between each other is large, bonding between each other may be (more) stabilized, and conditional energy may thereby be lowered and a low condition of energy may be achieved. The bonding energy between the second metal (e.g. Si) and the ligand (e.g. Cl) may be relatively greater than the bonding energy between the first metal (e.g. Ti) and the ligand (e.g. Cl). Therefore, the second metal reacts and is bonded with the ligand while the pretreatment gas (e.g. SiH4) is supplied, so that a bonding product (e.g. SiCl2) may be generated and the bonding between the first metal and the ligand which has relatively weak bonding energy may be disconnected. Accordingly, the first metal may be separated from the ligand.

Here, the second metal may be bonded with the ligand and generate a gas-phase bonding product and the product may be discharged from the inside of the process chamber180through purging and/or exhaust.

For example, the thin film deposition apparatus in accordance with an exemplary embodiment may deposit a titanium nitride (TiN) thin film, the source gas maybe TiCl4, the pretreatment gas may be silane (SiH4), and the reaction gas may be ammonia (NH3). At this point, the SiClxwhich is a bonding product may be more stabilized than TiCl4and/or silane (SiH4) and have a lower energy state.

The supply amount of the pretreatment gas per unit time may be greater than the supply amount of the source gas per unit time. The source gas is supplied into the process chamber180in a gas phase or a vapor phase, and the source gas may have more number of atoms of the ligand which is a non-metal than the first metal which is a metal. In addition, in order to disconnect the bonding between the first metal and the ligand by being bonded with the ligand, the second metal which is a metal different from the first metal should be used. Here, the second metal may be included in the gas-phase or vapor-phase pretreatment gas such that only one atom is included per molecule, and thus, in order to supply the second metal corresponding to the ligand which has many atoms, the supply amount of the pretreatment gas per unit time have to be increased compared to the supply amount of the source gas per unit time. That is, the supply amount of the pretreatment gas per unit time is increased compared to the supply amount of the source gas per unit time, so that all the ligand in the source gas may be configured to maximally react and be bonded with the second metal. Accordingly, all the first metal may maximally be separated from the ligand, generate a bonding product of the second metal and the ligand, and discharge the bonding product from the inside of the process chamber180.

For example, the source gas (e.g. TiCl4) may be supplied in a supply amount of approximately 0.1 to 1 slm. In addition, the pretreatment gas (e.g. SiH4) may be supplied in an amount of no more than approximately 2 slm and be supplied in a greater amount (or, supply amount per unit time) than the supply amount (or supply amount per unit time) of the source gas. Here, the slm refers to a standard litters per minute, and indicates litters (flow rate) per minute in a standard state.

At this point, the ratio of the supply amount of the pretreatment gas to the supply amount of the source gas per unit time may be no more than approximately 1:10. That is, the supply amount of the pretreatment gas per unit time may not exceed approximately 10 times the supply amount of the source gas per unit time. When the supply amount of the pretreatment gas per unit time exceeds approximately 10 times the supply amount of the source gas per unit time, the second metal becomes more than the ligand and the second metal may be deposited on the substrate10and act as an impurity in the thin film.

Meanwhile, in order to supply the second metal (e.g. Si) in a gas phase or a vapor phase, the pretreatment gas (e.g. SiH4) may include a non-metal element (or gas element) such as hydrogen (H) bonded with the second metal. The pretreatment gas may be separated from the second metal and present in a gas state (e.g. H2), or be bonded with the ligand (e.g. Cl) and present as a composite gas (e.g. HCl). Here, the non-metal element and/or the composite gas may also be discharged from the inside of the process chamber180through purging and/or exhaust. That is, the pretreatment gas may be composed of the second metal that may react with the ligand and generate a bonding product and a gas element bonded with the second metal.

In addition, referring toFIG. 3, a single cycle may mean that only the source gas is supplied for a certain time period (or predetermined time period), and after the source gas and the pretreatment gas are supplied together (co-flow) for a certain time period, the reaction gas is supplied. Here, a plurality of cycles (or periods) may be repeated and the thin film with a desired thickness may be deposited (or formed).

Referring again to (a) ofFIG. 4, after the source gas and the pretreatment gas are supplied together (co-flow) for a certain time period, the purge gas is supplied, and thus, the inside of the process chamber180may be purged. Here, the atmosphere gas may be continuously supplied, and the same gas as the atmosphere gas may be used as the purge gas.

Referring to (b) ofFIG. 4, the greater the time period for supplying the source gas and the pretreatment gas together (co-flow), the smaller the resistivity of the thin film may be. That is, as the time period for supplying together (co-flow) the source gas and the pretreatment gas increases, the resistivity of the thin film may be decreased with respect to the same thickness.

The thin film deposition apparatus100according to an exemplary embodiment may further include a pedestal140which is connected to a lower end section of the substrate boat130and supports the substrate boat130. The pedestal140may be connected to the lower end of the substrate boat130and support the substrate boat130, move up and down together with the substrate boat130, and be accommodated in a lower end section of the accommodating space of the inner tube122during a deposition process. In addition, the pedestal140may include a plurality of heat shield plates141disposed spaced apart from each other in multiple stages. The plurality of heat shield plate141may be connected to a plurality of supporters142and be disposed in multiple stages and be spaced apart from each other. At this point, the plurality of heat shield plate141may be configured as a baffle plate for preventing heat transfer in the vertical direction, and be composed of a material (e.g. opaque quartz) with low heat conductivity.

In addition, the pedestal140extends in the vertical direction and may further include: a plurality of supporters142; an upper plate143and a lower plate144which respectively fix the upper and lower ends of the plurality of supporters142; and a side cover145which surrounds the side surfaces of the plurality of heat shield plates141. The plurality of supporters142may extend in the vertical direction, be disposed spaced apart from each other in the horizontal direction, and support the plurality of heat shield plates141.

The upper plate143may fix the upper ends of the plurality of supporters142and be connected to the substrate boat130. The lower plate144may fix the lower ends of the plurality of supporters142and be connected (or coupled) to a shaft191. Here, the upper plates143and the lower plates144of the plurality of supporters142may form the skeleton of the pedestal140.

The side cover145may be formed so as to surrounding the side surface (or the side surfaces of the pedestal) of the plurality of heat shield plates141and be connected and fixed to the upper plates143and/or lower plates144.

The thin film deposition apparatus100according to an exemplary embodiment may further include an exhaust port communicating with an exhaust duct150. The exhaust port160may communicate with a lower portion of the exhaust duct150, and accordingly, the residue gas introduced to one end (or one side) of the exhaust port160communicating with the exhaust duct150may move to the other end (or the other side) along the exhaust port160and be discharged to the outside. For example, the residue gas may be discharged by an exhaust pump (not shown) connected directly or indirectly to the exhaust port160, and an exhaust pipe (not shown), which may extend an exhaust path between the exhaust port160and the exhaust pump (not shown), may also be provided.

The thin film deposition apparatus100according to an exemplary embodiment may further include a heater part170which provides thermal energy into the process chamber180(or into the inner tube). The heater part170may extend in the vertical direction outside the inner tube122and heat the inner tube122, and may be disposed so as to surround the side surface and an upper portion of the inner tube122or the outer tube121. At this point, the internal temperature of the process chamber180may be approximately 600° C. or lower, and a deposition process may favorably be performed at a temperature of approximately 400-500° C.

Meanwhile, a deposition process may be performed under a process conditions having an air pressure of no higher than approximately 10 Torr and a process temperature of no higher than approximately 500° C. so that the silicon atom (Si) of the silane (SiH4) used as the pretreatment gas and the chlorine atom (Cl) of TiCl4used as the source gas are well bonded and effectively generate silicon chloride (e.g. SiCl2) and the titanium atom (Ti) and the chlorine atom (Cl) may be smoothly separated in the TiCl4.

The thin film deposition apparatus100according to an exemplary embodiment may further include: a shaft191connected to the lower plate144of the pedestal140; a raising and lowering drive part192which is connected to the lower end of the shaft191and vertically moves the shaft191; a rotary drive part193which is connected to the lower end of the shaft191and rotates the shaft191; a support plate which is connected to the upper end of the shaft191and moves up and down together with the substrate boat130; a sealing member194aprovided between the inner tube122or the outer tube121and the support plate194; a bearing member194bprovided between the support plate194and the shaft191; and an insertion opening195through which the substrate10is loaded into the process chamber180.

The shaft191may be connected to the lower plate144of the pedestal140and function to support the pedestal140and/or the substrate boat130.

The raising and lowering drive part192may be connected to the lower end of the shaft191and vertically move the shaft191, and thereby raise and lower the substrate boat130.

The rotary drive part193may be connected to the lower end of the shaft191so as to rotate the substrate boat130, rotate the shaft191, and thereby rotate the substrate boat130around the shaft191.

The support plate194may be connected to the upper end of the shaft191and move up and down together with the substrate boat130, and may function to seal the accommodation space of the inner tube122and/or the inner space of the outer tube121when the substrate boat130is accommodated in the accommodation space of the inner tube122.

The sealing member194amay be provided between the support plate194and the inner tube122and/or between the support plate194and the outer tube121, and seal the accommodation space of the inner tube122and/or the inner space of the outer tube121.

The bearing member194bmay be provided between the support plate194and the shaft191and rotate in a state in which the shaft191is supported by the bearing member194b.

The insertion opening195may be provided on one side (e.g. one side of the lower chamber) of the process chamber180, and the substrate10may be loaded into the process chamber180through the insertion opening195in a transfer chamber200. An introducing opening210may be formed one side of the transfer chamber200corresponding to the insertion opening195of the process chamber180, and a gate valve250may be provided between the introducing opening210and the insertion opening195. Accordingly, the inside of the transfer chamber200and the inside of the process chamber180may be separated by the gate valve250, and the introducing opening210and the insertion opening195may be opened/closed by the gate valve250.

FIG. 5is a flowchart illustrating a thin film deposition method in accordance with another embodiment of the present invention.

Referring toFIG. 5, a thin film deposition method in accordance with another exemplary embodiment will be described in detail, and matters that overlap the portion previously described about the thin film deposition apparatus in accordance with an exemplary embodiment will be omitted.

A thin film deposition method in accordance with another exemplary embodiment may include: step S100for supplying a source gas including a first metal and a ligand into a process chamber to which a substrate is supplied; step S200for supplying a pretreatment gas including a second metal reactable with the ligand into the process chamber; and step S300for supplying, into the process chamber, a reaction gas including a reactant source which reacts with the first metal and forms a thin film.

First, a source gas including a first metal and a ligand is supplied into a process chamber to which a substrate is supplied (S100). A precursor compound including the first metal and the ligand may be supplied as the source gas into the process chamber, the first metal (layer) may be deposited on the substrate, and a first metal atom layer (or unit layer) may be deposited in the case of an atomic layer deposition (ALD).

Next, a pretreatment gas including a second metal reactable with the ligand is supplied into the process chamber (S200). The pretreatment gas including the second metal reactable with the ligand may be supplied into the process chamber. The second metal may be caused to react and bonded with the ligand by supplying the pretreatment gas into the process chamber to which the source gas is supplied. In addition, the second metal is bonded with the ligand and thus the bonding between the first metal and the ligand may be disconnected. Accordingly, the bonding between the first metal and the ligand may be effectively disconnected in the source gas, and the first metal may be suppressed or prevented from being deposited in a state of being bonded with the ligand.

Next, a reaction gas including a reactant source which reacts with the first metal and forms a thin film is supplied into the process chamber (S300). The reaction gas including the reactant source may be supplied into the process chamber, and the reactant source may be caused to react with the first metal (layer) on the substrate to form a thin film (that is, a desired thin film).

The step S100for supplying the source gas and the step S300for supplying the reaction gas may be alternately performed. That is, the source gas and the reaction gas may be supplied in a temporally separate manner. When the reaction gas and the source gas are supplied together, the first metal in the source gas may react with the reactant source of the reaction gas before the ligand is disconnected from the source gas, and the thin film may be formed on the first metal in a state of being bonded with the ligand. Accordingly, the ligand is included in the thin film and act as an impurity, and the resistivity of the thin film may be increased. In addition, the first metal and the reactant source do not react on the uppermost layer (uppermost surface) on the substrate10but react in the air above the substrate, so that the coupling power (or suction force of the formed substrate with respect to the substrate) between the formed thin film and the substrate may also be weakened.

However, when the reaction gas is supplied at a temporally separate time with respect to the source gas, only the first metal deposited on the substrate may be caused to react with the reactant source. Accordingly, the ligand may be suppressed or prevented from being contained in the thin film as an impurity, and may improve the resistivity of the thin film by reducing the resistivity of the thin film.

At this point, the reaction gas may be supplied in a temporally separate manner also with the pretreatment gas. When the reaction gas is supplied together with the pretreatment gas, the second metal included in the pretreatment gas reacts with the reaction gas, and thus a byproduct film (that is, undesired thin film) may be formed. However, when the reaction gas is supplied at a temporally separate manner with the pretreatment gas, the second metal may be prevented from reacting with the reaction gas and forming the byproduct film.

Step S250for supplying a purge gas into the process chamber may further be included between the step S100for supplying the source gas and the step S300for supplying the reaction gas.

A purge gas may be supplied into the process chamber (S250). The source gas, the pretreatment gas and/or the residue gas of the reaction gas, and/or the deposition byproduct may be purged by supplying the purge gas into the process chamber and may be removed from the inside of the process chamber. At this point, the purge gas may include a nitrogen (N2) gas, or an inert gas such as argon (Ar), helium (He) or neon (Ne). Accordingly, the step S100for supplying the source gas and the step S300for supplying the reaction gas may be reliably separated in time. In addition, the residue gas and/or the deposition byproduct may be removed through purging, and only the thin film formed by the reaction between the first metal and the reactant source react may remain (or be present) on the substrate, and thus, the impurities of the thin film may be minimized.

The step S200for supplying the pretreatment gas into the process chamber may be performed during at least a portion of the time period for supplying the source gas while performing the step S100for supplying the source gas. The pretreatment gas may be supplied during at least a portion of the time period for supplying the source gas, and the pretreatment gas may be supplied together with the source gas for a certain time period (or predetermined time period). The pretreatment gas function to separate the first metal and the ligand by disconnecting the bonding between the first metal and the ligand before the first metal is deposited on the substrate10, and therefore the pretreatment gas needs to be supplied together (co-flow) with the source gas. To this end, the pretreatment gas may be supplied during at least a portion of the time period for supplying the source gas. Accordingly, the first metal and the ligand are separated before the first metal is deposited on to the substrate10, so that the first metal deposited in a state of being bonded with the ligand may be minimized.

The step S200for supplying the pretreatment gas into the process chamber may be performed while supplying a greater supply amount of the pretreatment gas than the source gas. The source gas is supplied into the process chamber in a gas phase or a vapor phase, and the source gas may have more number of atoms of the ligand, which is a non-metal, than the first metal which is a metal. In addition, in order to disconnect the bonding between the first metal and the ligand by being bonded with the ligand, the second metal which is a metal different from the first metal should be used. Here, the second metal may be included in the gas-phase or vapor-phase pretreatment gas such that only one atom is included per molecule, and thus, in order to supply the second metal corresponding to the ligand which has many atoms, the supply amount of the pretreatment gas per unit time have to be increased compared to the supply amount of the source gas per unit time. That is, the supply amount of the pretreatment gas per unit time is increased compared to the supply amount of the source gas per unit time, so that all the ligand in the source gas may be configured to maximally react and be bonded with the second metal. Accordingly, all of the first metal may be separated from the ligand, generate a bonding product of the second metal and the ligand, and discharge the bonding product from the inside of the process chamber.

At this point, the ratio of the supply amount of the pretreatment gas to the supply amount of the source gas per unit time may be no more than approximately 1:10. That is, the supply amount of the pretreatment gas per unit time may not exceed approximately 10 times the supply amount of the source gas per unit time. When the supply amount of the pretreatment gas per unit time exceeds approximately 10 times the supply amount of the source gas per unit time, the second metal becomes more than the ligand and the second metal may be deposited on the substrate10and act as an impurity in the thin film.

The step S100for supplying the source gas may be performed for a longer time period than the step S200for supplying the pretreatment gas into the process chamber. That is, the time period for supplying the source gas may be longer than the time period for supplying the pretreatment gas. For example, before the source gas and the pretreatment gas are supplied together (co-flow), only the source gas is supplied, and the first metal may be caused to be deposited on the substrate than the second metal.

The step S100for supplying the source gas may be performed earlier than the step S200for supplying the pretreatment gas into the process chamber. That is, before the source gas and the pretreatment gas are supplied together (co-flow), only the source gas is supplied, and the first metal may be caused to be deposited earlier on the substrate than the second metal. Accordingly, it is not only possible to cause the second metal not to be deposited on the substrate10but to react with the ligand, but also possible to prevent the second metal from being deposited on the substrate10. That is, the second metal may also be an atom (or matter) that may be deposited on the substrate. Thus, when the source gas and the pretreatment gas are started to be supplied together, the second metal may be deposited on the substrate and react with the reaction gas to form the byproduct film. In addition, the second metal may be contained in the thin film and act as an impurity.

However, when only the source gas is first supplied during a certain time period (or predetermined time period), it is possible to induce such that the first metal (layer) is first deposited on the substrate and only the first metal is deposited on the substrate. In addition, not only the ligand may be suppressed or prevented from being contained in the thin film by causing the second metal to disconnect, through the bonding with the ligand, the bonded ligand from the first metal that has been deposited in a state of being bonded with the ligand, but also the second metal may be prevented from being deposited on the substrate. Accordingly, the second metal may be induced to react only with the ligand, and the bonding product generated by the reaction (or bonding) of the second metal and the ligand may be discharged from the inside of the process chamber.

The second metal may have greater bonding energy with the ligand than the first metal. Large bonding energy between each other means that bonding is well established and is not easily disconnected, and small bonding energy means that bonding power is weak and is easily disconnected. The bonding energy between the second metal (e.g. Si) and the ligand (e.g. Cl) may be relatively greater than the bonding energy between the first metal (e.g. Ti) and the ligand (e.g. Cl). Therefore, the second metal reacts and is bonded with the ligand while the pretreatment gas (e.g. SiH4) is supplied, so that a bonding product (e.g. SiCl2) may be generated and the bonding between the first metal and the ligand which has relatively weak bonding energy may be disconnected. Accordingly, the first metal may be separated from the ligand.

Hereinafter, a thin film deposition method in accordance with still another exemplary embodiment will be described in more detail, and matters overlapping the portions described above relating to the thin film deposition apparatus in accordance with another exemplary embodiment, and related to the thin film deposition method in accordance with an exemplary embodiment will be omitted.

A thin film deposition method in accordance with another exemplary embodiment may include: step S10for supplying a source gas including titanium (Ti) and a ligand into a process chamber to which a substrate is loaded; step S20for supplying a pretreatment gas including silicon (Si) reactable with the ligand into the process chamber; and step S30for supplying, into the process chamber, a reaction gas including a nitrogen atom (N) which reacts with titanium (Ti) and forms a titanium nitride (TiN) thin film.

First, a source gas including a first metal and a ligand is supplied into a process chamber to which a substrate is loaded (S10). The source gas may include titanium (Ti) and a ligand (e.g. chlorine element), be TiCl4, and deposit titanium (Ti) (layer) on the substrate.

Next, a pretreatment gas including silicon (Si) reactable with the ligand is supplied into the process chamber (S20). The pretreatment gas may include silicon (Si) reactable with the ligand (e.g. chlorine element) and be silane (SiH4). The silicon (Si) of the pretreatment gas may react with the ligand (e.g. Cl of TiCl4) and generate a gas-phase bonding product (e.g. SiCl2) and disconnect the boding between the titanium (Ti) and the ligand.

Next, a reaction gas including a nitrogen atom (N) which reacts with the titanium (Ti) and forms a titanium nitride (TiN) thin film is supplied into the process chamber (S30). The reaction gas may include a nitrogen atom (N) reacting with the titanium (Ti) to form a titanium nitride (TiN) thin film, and be ammonia (NH3). At this point, a gas element (e.g. H) bonded with the nitrogen atom (N) may be separated from the nitrogen atom (N) and be present in a gas state, or may be bonded with the ligand (e.g. Cl) and generate a composite gas.

Accordingly, the bonding between the titanium (Ti) and the ligand may be effectively disconnected in the source gas, and the titanium (Ti) may be suppressed or prevented from being deposited in a state of being bonded with the ligand. Accordingly, the ligand such as chlorine atom (Cl) in the titanium nitride (TiN) thin film may be suppressed or prevented from being contained as an impurity, and the resistivity characteristics of the titanium nitride (TiN) thin film may be improved by reducing the resistivity of the titanium nitride (TiN) thin film.

As such, an exemplary embodiment includes a pretreatment gas nozzle part configured to supply a pretreatment gas including a second metal reacting with a ligand of a source gas, so that bonding between the first metal and the ligand may be effectively disconnected by supplying the pretreatment gas during a process for depositing a first metal. Thus, the first metal may be suppressed or prevented from being deposited in a state of being bonded with the ligand. Accordingly, the ligand may be suppressed or prevented from being contained in the thin film as an impurity, and the resistivity of the thin film may be improved by reducing the resistivity of the thin film. That is, the second metal of the pretreatment gas meets the source gas, disconnects the bonding between the first metal and the ligand and is bonded with the ligand, and thus, the bonding between the first metal and the ligand may be effectively disconnected. In addition, the first metal is effectively separated from the ligand, and the first metal deposited in a state of being bonded with the ligand may be minimized. In addition, the pretreatment gas and the reaction gas are separately supplied, so that the second metal may be prevented from reacting with the reaction gas and forming a byproduct film and only the first metal deposited on the substrate may be caused to react with the reaction gas. In addition, only the source gas is supplied before the predetermined gas is supplied and thus may cause the first metal to be deposited on the substrate earlier than the second metal. Accordingly, the second metal may be caused not to be deposited on the substrate and react with the ligand, and the second metal may be prevented from being deposited on the substrate. Meanwhile, the supply amount of the pretreatment gas per unit time is increased compared to the supply amount of the source gas per unit time, so that all the ligand in the source gas may be configured to maximally react and be bonded with the second metal. Thus, all of the first metal may be maximally separated from the ligand and discharge the bonding product from the inside of the process chamber. So far, preferred exemplary embodiments have been illustrated and described, but the present disclosure is not limited to the above-mentioned embodiments, and it will be understood to those skilled in the art to which the present disclosure belongs that various modifications and equivalent embodiments may be made from the present disclosure without departing from spirits and scopes of the present disclosure. Hence, the technical protective scope of the present invention shall be determined by the technical scope of the accompanying claims.