Substrate processing apparatus and method

Abstract

A substrate processing method capable of stably performing atomic layer etching without damaging a process chamber is provided. The substrate processing method includes the steps of providing a substrate including a target layer into a chamber, forming a first plasma in the chamber with a first gas including chlorine to perform a first modification on the target layer, forming a second plasma in the chamber with a second gas including oxygen to perform a second modification on the first modified target layer, providing a precursor into the chamber to react the second modified target layer with the precursor, and repeating the forming the first plasma, the forming the second plasma, and the providing the precursor to remove at least a portion of the target layer.

Description

Technical Field

[0001] This invention relates to a substrate processing apparatus and method. Background Technology

[0002] In the manufacture of semiconductor devices, various processes such as etching, photolithography, ashing, ion implantation, thin film deposition, and cleaning are performed.

[0003] Here, in the etching process, atomic layer etching (ALE) is a technique that can adjust the etching depth of the target layer at the atomic level while minimizing electrical and physical damage. ALE is considered an essential technique for fabricating nanoscale electronic circuits. Summary of the Invention

[0004] On the other hand, when performing atomic layer etching on aluminum oxide (Al2O3), plasma based on fluorine-based sources (e.g., NbF5) is typically used. However, fluorine-based sources can corrode the inner walls / parts of the process chamber or be absorbed into the inner walls / parts, making them difficult to clean.

[0005] The technical problem to be solved by the present invention is to provide a substrate processing method that can stably perform atomic layer etching without damaging the process chamber.

[0006] Another technical problem to be solved by the present invention is to provide a substrate processing apparatus capable of stably performing atomic layer etching without damaging the process chamber.

[0007] The technical problems of this invention are not limited to those described above. Those skilled in the art can clearly understand other technical problems not mentioned in the following description.

[0008] An aspect of the substrate processing method of the present invention for solving the above-mentioned technical problems includes the following steps: providing a substrate including a target layer into a chamber; forming a first plasma in the chamber using a first gas including chlorine to perform a first modification on the target layer; forming a second plasma in the chamber using a second gas including oxygen to perform a second modification on the first-modified target layer; providing a precursor into the chamber to react the second-modified target layer with the precursor; and repeating the processes of forming the first plasma, forming the second plasma, and providing the precursor to remove at least a portion of the target layer.

[0009] Another aspect of the substrate processing method of the present invention for solving the above-mentioned technical problems includes: introducing a substrate having a semiconductor device formed thereon into a cavity, the semiconductor device comprising: a first interlayer insulating film; a second interlayer insulating film formed on the first interlayer insulating film; a semiconductor pattern penetrating the first interlayer insulating film and the second interlayer insulating film; a charge trapping film conformally formed along an upper surface of the first interlayer insulating film, a lower surface of the second interlayer insulating film, and a sidewall of the semiconductor pattern; a barrier film conformally formed along the charge trapping film; and a conductive film formed to contact the barrier film, wherein a portion of the barrier film is exposed by the conductive film; forming a first plasma in the cavity using a first gas including chlorine; forming a second plasma in the cavity using a second gas including oxygen; providing a precursor into the cavity to cause the barrier film exposed by the conductive film to react with the precursor; and repeatedly performing the formation of the first plasma, the formation of the second plasma, and the provision of the precursor to remove at least a portion of the barrier film exposed by the conductive film.

[0010] An aspect of the substrate processing apparatus of the present invention for solving another technical problem mentioned above includes: a heat source disposed within a chamber and configured to heat a substrate; a gas supply system configured to supply a first gas, a second gas, and a precursor to the chamber; an electrode system for generating plasma using the first gas or the second gas supplied to the chamber; and a controller configured to control the heat source, the gas supply system, and the electrode system to perform atomic layer etching on a target layer of the substrate, wherein the atomic layer etching includes the following steps: supplying the first gas, comprising chlorine, to the chamber and forming a first plasma based on the first gas to perform a first modification on the target layer; supplying the second gas, comprising oxygen, to the chamber and forming a second plasma based on the second gas to perform a second modification on the first modified target layer; providing the precursor to the chamber to cause the second modified target layer to react with the precursor; and repeatedly performing the formation of the first plasma, the formation of the second plasma, and the provision of the precursor to remove at least a portion of the target layer.

[0011] Specific details of other embodiments are included in the detailed description and accompanying drawings. Attached Figure Description

[0012] Figure 1 This is a diagram illustrating a substrate processing apparatus according to an embodiment of the present invention.

[0013] Figure 2 This is a flowchart illustrating a substrate processing method according to some embodiments of the present invention.

[0014] Figure 3 It is used for explanation Figure 2 Timing diagram of the substrate processing method.

[0015] Figure 4 This is a diagram illustrating a substrate processing apparatus according to another embodiment of the present invention.

[0016] Figure 5 This is a diagram illustrating a substrate processing apparatus according to another embodiment of the present invention.

[0017] Figure 6 and Figure 7 This is a diagram illustrating an example of a substrate processing method applied according to some embodiments of the present invention.

[0018] Figure 8 This is a diagram illustrating experimental results using a substrate processing method according to some embodiments of the present invention.

[0019] Explanation of reference numerals in the attached figures

[0020] 100: Chamber; 102: Processing space

[0021] 150, 155, 156: Heat source; 160, 161, 162: Input port

[0022] 170: Outlet port; 190: Electrode system

[0023] 191: Upper electrode; 199: RF generator

[0024] 200: Gas supply system; 300: Controller

[0025] G1: First gas; G2: Second gas

[0026] PC: precursor; GC: inert gas Detailed Implementation

[0027] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings. The advantages and features of the present invention, as well as methods for achieving these advantages and features, will be explained below with reference to the accompanying drawings. Figure 1 The invention becomes clear from the detailed description of the embodiments. However, the invention is not limited to the embodiments disclosed below, but can be implemented in many different forms. These embodiments are provided only to make the disclosure of the invention complete and to fully inform those skilled in the art of the scope of the invention, which is defined only by the scope of the claims. Throughout the specification, the same reference numerals refer to the same constituent elements.

[0028] To readily describe the relationship between one element or component and another, as shown in the figure, spatial relative terms such as "below," "below," "lower," "above," and "upper" can be used. It should be understood that, in addition to the orientation shown in the figure, spatial relative terms also include terms indicating the different orientations of the elements during use or operation. For example, when the element shown in the figure is flipped, an element described as "below" or "below" of another element may be located "above" of that element. Therefore, the exemplary term "below" can include both "below" and "above" orientations. An element may also be oriented in another direction, thus allowing the spatial relative terms to be interpreted according to orientation.

[0029] Although the terms "first," "second," etc., are used to describe various elements, constituent elements, and / or parts, these elements, constituent elements, and / or parts are obviously not limited by these terms. These terms are only used to distinguish one element, constituent element, and / or part from another element, constituent element, and / or part. Therefore, the first element, first constituent element, or first part mentioned below can obviously also be a second element, second constituent element, or second part within the technical concept of the present invention.

[0030] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. When describing the invention with reference to the drawings, identical or corresponding constituent elements are given the same reference numerals, regardless of the reference numerals, and repeated descriptions thereof are omitted.

[0031] Figure 1 This is a diagram illustrating a substrate processing apparatus according to an embodiment of the present invention.

[0032] refer to Figure 1 According to an embodiment of the present invention, the substrate processing apparatus 1 is an apparatus for performing atomic layer etching. This substrate processing apparatus 1 includes a chamber 100, a heat source 155, an electrode system 190, a gas supply system 200, and a controller 300.

[0033] A target layer is formed on the substrate W, and at least a portion of the target layer can be etched by the atomic layer etching method described later. The target layer may include at least one of a metal oxide (e.g., aluminum oxide (Al2O3), hafnium oxide (HfO2), zirconium oxide (ZrO2)), silicon oxide (SiO2), silicon nitride (Si3N4), and titanium nitride (TiN).

[0034] The chamber 100 provides a processing space 102 for processing the substrate W. For example, the chamber 100 may be a circular cylindrical shape and may be made of metal. Inlets 161 and 162 for supplying process gases are provided on the side walls of the chamber 100. An outlet 170 is provided on the bottom surface of the chamber 100 for discharging byproducts generated in the processing space 102 to the outside.

[0035] A heat source 155 may be disposed on the upper surface of the chamber 100. The heat source 155 may be a flash lamp, IR lamp, RTP, laser, heater, etc., but is not limited thereto. The heat source 155 adjusts the temperature of the substrate W to a temperature range suitable for atomic layer etching. For example, the heat source 155 can adjust the temperature of the substrate W to above 50°C and below 400°C, but is not limited thereto. A substrate support stage 110 is disposed within the processing space 102 of the chamber 100, and the substrate W is placed on the substrate support stage 110.

[0036] Electrode system 190 may include an upper electrode 191, an RF generator 199, a lower electrode (not shown), etc. The RF generator 199 may include an RF source for generating an RF bias voltage and an impedance matching network for adjusting the RF bias voltage. The impedance-regulated RF bias voltage is provided to the upper electrode 191. The lower electrode (not shown) may be embedded within the substrate support stage 110 and may be grounded.

[0037] The gas supply system 200 is configured to supply process gases through inlets 161 and 162. Specifically, the gas supply system 200 selectively supplies a first gas G1, a second gas G2, and a precursor PC to the chamber 100. Although not shown, the gas supply system 200 additionally supplies an inert gas (e.g., Ar) to the chamber 100.

[0038] The first gas storage unit 210 stores the first gas G1, and the first flow regulating unit 211 provides an appropriate flow rate to the chamber 100 according to the control of the controller 300. The first flow regulating unit 211 may be composed of a valve, an MFC (Mass Flow Controller), or the like. The first gas G1 may be a gas including chlorine (i.e., a chlorine source), and may be at least one selected from, for example, the group consisting of Cl2, HCl, SiCl4, CCl4, and BCl3.

[0039] The second gas storage unit 220 stores the second gas G2, and the second flow regulating unit 221 provides an appropriate flow rate to the chamber 100 according to the control of the controller 300. The second gas G2 may be a gas including oxygen (i.e., an oxygen source), and may be at least one selected, for example, from the group consisting of O2, H2O, N2O and O3.

[0040] The third gas storage unit 230 stores the precursor PC, and the third flow regulating unit 231 provides an appropriate flow rate to the chamber 100 according to the control of the controller 300. The precursor PC may include a diketone gas. For example, the precursor PC may be at least one selected from the group consisting of Hfac (Hexafluoroacetylacetone), Acac (Acetylacetone), and Dmac (Dimethylacetamide).

[0041] The controller 300 is configured to control the heat source 155, the gas supply system 200, the electrode system 190, etc., to perform atomic layer etching on the target layer of the substrate W.

[0042] The following is for reference. Figure 2 and Figure 3 Detailed explanation of atomic layer etching methods. Figure 2 This is a flowchart illustrating a substrate processing method according to some embodiments of the present invention. Figure 3 It is used for explanation Figure 2 Timing diagram of the substrate processing method.

[0043] refer to Figure 1 and Figure 2 The following explanation addresses the case where the target layer formed on substrate W is aluminum oxide (Al2O3).

[0044] The target layer formed on the substrate W is etched by atomic layer deposition. Atomic layer etching is performed by continuous repeating cycles. One cycle can be performed within 1 second (maximum 3 seconds). One cycle can be performed at the nanosecond (ns) to millisecond (ms) level. One cycle includes the following steps: One cycle includes performing a pretreatment on the substrate W (S10) and performing thermal etching (i.e., t-ALE) on the pretreated substrate W (S20).

[0045] Specifically, the pretreatment (S10) includes two consecutive plasma treatment steps (S12, S14).

[0046] The substrate W is subjected to a first plasma treatment (S12) using a chlorine source.

[0047] Specifically, a first gas G1 (i.e., a chlorine source) comprising chlorine is supplied into chamber 100. The first gas G1 may be, for example, at least one selected from the group consisting of Cl2, HCl, SiCl4, CCl4, and BCl3. Hereinafter, the case where the first gas G1 is Cl2 will be described as an example.

[0048] A first plasma is formed based on a first gas G1, and the first plasma performs a first modification on the target layer (i.e., Al2O3), as shown in Formula 1 below. In Formula 1 below, the symbol (s) denotes a solid.

[0049]

Chemical Formula 1

[0050] Cl2 + Al2O3(s) → AlCl x -(Al2O3)(s)

[0051] Next, a second plasma treatment (S14) is performed on the substrate W using an oxygen source.

[0052] Specifically, a second gas G2 comprising oxygen (i.e., an oxygen source) is supplied into chamber 100. The second gas G2 may be, for example, at least one selected from the group consisting of O2, H2O, N2O, and O3. Hereinafter, the case where the second gas G2 is O2 will be described as an example.

[0053] A second plasma is formed based on the second gas G2, and the second plasma reacts with the target layer (AlCl) after the first modification. x The second modification is carried out using Al₂O₃, as shown in Formula 2 below. In Formula 2 below, the symbol (s) indicates a solid.

[0054]

Chemical Formula 2

[0055] O2+AlCl x -(Al2O3)(s)→O-AlCl3(s)+(Al2O3)(s)

[0056] Next, thermal etching (t-ALE) is performed by supplying a precursor (S20).

[0057] Specifically, performing thermal etching (S20) includes maintaining the substrate W at a preset temperature (i.e., a third temperature) while providing a precursor PC into the chamber 100. The precursor PC may include a diketone-type gas. The precursor PC may be at least one selected from, for example, Hfac (Hexafluoroacetylacetone), Acac (Acetylacetone), and Dmac (Dimethylacetamide). Hereinafter, the case where the precursor PC is Hfac will be described as an example.

[0058] The target layer O-AlCl3, after the second modification, reacts with the precursor PC, as shown in Formula 3, thereby removing a portion of the target layer. In Formula 3 below, the symbol (s) represents a solid and the symbol (g) represents a gas.

[0059]

Chemical Formula 3

[0060] Hfac(g) + O-AlCl3(s) + (Al2O3)(s)

[0061] →2Al(Hfac)3(g)+AlCl3(g)+HCl(g)+H2O(g)+(Al2O3)(s)

[0062] On the other hand, during thermal etching (S20), the substrate W can be maintained at a preset temperature, namely above 50°C and below 400°C. Within this temperature range, as the temperature increases, the thickness of the target layer etched in one cycle can increase. For example, if the substrate W is maintained at 150°C, etching can be performed in one cycle. to With the substrate W maintained at 250°C, etching can be performed in one cycle. to With the substrate W maintained at 350°C, etching can be performed in one cycle. to These thicknesses are exemplary and can vary depending on the type and quantity of the first gas G1, the second gas G2, the precursor PC, etc.

[0063] Furthermore, during thermal etching (S20), the set temperature of the substrate W can be selected differently depending on the type of material of the target layer, the thickness of the target layer, the amount to be etched, the process time, etc. That is, according to some embodiments of the present invention, thermal etching (S20) has a wide etch window from low temperature (e.g., 50°C) to high temperature (e.g., 400°C).

[0064] Next, it is checked whether the loop has repeated the preset number of times (S30). If the loop has not repeated the preset number of times, the process returns to step S10 to perform preprocessing. Conversely, if the preset number of times has been repeated, the atomic layer etching process ends.

[0065] On the other hand, during the first plasma treatment (S12), the substrate W can be controlled at a first temperature, and during the second plasma treatment (S14), the substrate W can be controlled at a second temperature. Furthermore, during the thermal etching (S20) performed by supplying a precursor, the substrate W can be controlled at a third temperature.

[0066] The first temperature and the second temperature can be the same as each other.

[0067] Alternatively, the third temperature can be controlled to be the same as the first and second temperatures. That is, the temperature of the substrate W can be controlled to be the same during the execution of the first plasma treatment (S12), the execution of the second plasma treatment (S14), and the execution of thermal etching (t-ALE) (S20).

[0068] Alternatively, the first and second temperatures can be controlled to be the same, and the third temperature can be controlled to be higher than the first and second temperatures. To freely control the temperatures of each step S12, S14, and S20, the heat source 155 can be placed on the upper surface of the chamber 100 or on the side wall of the chamber 100 (see reference). Figure 5 (156).

[0069] The temperature of the substrate W can be controlled differently in each step of performing the first plasma treatment (S12), the second plasma treatment (S14), and the thermal etching (t-ALE) (S20) by using a heat source 155 such as a flash lamp. For example, the temperature of the substrate W can be maintained at the same level during the first plasma treatment (S12) and the second plasma treatment (S14), and the temperature of the substrate W can be increased during the thermal etching (S20). (See reference here.) Figure 3 Cycle I corresponds to times t1 to t7. The first plasma treatment (S12) is performed for times t1 to t3, the second plasma treatment (S14) is performed for times t3 to t5, and thermal etching (S20) is performed for times t5 to t7.

[0070] During times t1 to t2, a first gas G1 comprising chlorine is supplied to chamber 100, and a first plasma is formed within chamber 100. An inert gas GC (e.g., Ar) is also supplied to chamber 100 along with the first gas G1. The inert gas GC acts as a carrier for transporting the first gas G1. The target layer undergoes a first modification via the first plasma.

[0071] During time intervals t2 and t3, inert gas GC continues to be supplied. The inert gas GC is used to remove byproducts from inside chamber 100.

[0072] During times t3 to t4, a second gas G2, including oxygen, is supplied to chamber 100, and a second plasma is formed within chamber 100. An inert gas GC (e.g., Ar) is also supplied to chamber 100 along with the second gas G2. The inert gas GC acts as a carrier for transporting the second gas G2. The second modification is carried out through the target layer of the first modification via the second plasma.

[0073] During time intervals t4 and t5, inert gas GC continues to be supplied. The inert gas GC is used to remove byproducts from inside chamber 100.

[0074] During times t5 to t6, a precursor PC is supplied to chamber 100. The target layer, which has undergone the second modification, reacts with the precursor PC. During times t6 to t7, an inert gas GC continues to be supplied. The inert gas GC is used to remove byproducts from inside chamber 100. The reacted target layer (i.e., Al(hfac)3) is in gaseous form and is discharged to the outside along with the inert gas GC. Therefore, the target layer is thermally etched.

[0075] End the first loop (I).

[0076] During time intervals t7 to t8, the second loop II begins. The steps are repeated, which are essentially the same as those in the first loop I.

[0077] In summary, the substrate processing method according to some embodiments of the present invention allows for atomic layer etching of the target Al2O3 layer without the use of a fluorine-based source. That is, the target layer can be pretreated using chlorine and oxygen sources, and thermal etching can be performed by supplying a precursor, thereby performing atomic layer etching of the target layer. Since no fluorine-based source is used, denaturation and corrosion of the portion within chamber 100 do not occur.

[0078] Figure 4 This is a diagram illustrating a substrate processing apparatus according to another embodiment of the present invention. Figure 5 This diagram illustrates a substrate processing apparatus according to yet another embodiment of the present invention. For ease of explanation, the main focus is on description and utilization. Figures 1 to 3 The characteristics described are different.

[0079] First, refer to Figure 4 In a substrate processing apparatus 2 according to another embodiment of the present invention, an inlet 160 for supplying process gas is provided on the upper surface of the chamber 100. A heater serving as a heat source 150 is provided inside the substrate support stage 110.

[0080] refer to Figure 5 In another embodiment of the substrate processing apparatus 3 according to the present invention, an inlet 160 for supplying process gas is provided on the upper surface of the chamber 100. A heat source 156 is provided on the side surface of the chamber 100. A heater may not be provided in the substrate support stage 110. The heat source 156 may be a flash lamp, IR lamp, RTP, laser, heater, etc.

[0081] By utilizing a heat source 156 such as a flash lamp, the temperature of the substrate W can be controlled differently in each step of performing the first plasma treatment (S12), the second plasma treatment (S14), and the thermal etching (t-ALE) (S20). For example, the temperature of the substrate W can be maintained at the same level during the first plasma treatment (S12) and the second plasma treatment (S14), and the temperature of the substrate W can be increased during the thermal etching (S20).

[0082] Specifically, the steps of performing the first plasma treatment (S12), the second plasma treatment (S14), and the thermal etching (t-ALE) (S20) can be performed in a dual-process chamber 100 (reference) capable of simultaneously performing plasma treatment and thermal treatment. Figure 1 , Figure 4 and Figure 5 ) is executed.

[0083] Figure 6 and Figure 7 This is a diagram illustrating an example of a substrate processing method applied according to some embodiments of the present invention. Figure 6 and Figure 7 The following description uses the application of a substrate processing method according to some embodiments of the present invention to the manufacture of a vertical storage device (e.g., a three-dimensional NAND flash memory device) as an example. That is, it can be used in the process of removing a portion of the barrier film 370 of the vertical storage device.

[0084] refer to Figure 6 To chamber 100 (reference) Figure 1 A substrate W in which a semiconductor device (i.e., a vertical memory device) is formed is introduced into the substrate.

[0085] Specifically, the vertical memory device includes multiple interlayer insulating films 315a, 315b stacked in one direction (i.e., the vertical direction). A semiconductor pattern 420 is included, penetrating the multiple interlayer insulating films 315a, 315b. The semiconductor pattern 420 may include single-crystal silicon, either doped or undoped. The semiconductor pattern 420 includes a channel region.

[0086] A unit forming space 99 is positioned between adjacent interlayer insulating films (i.e., the first interlayer insulating film 315a and the second interlayer insulating film 315b).

[0087] A tunneling film 390 is formed on the semiconductor pattern 420 exposed by the cell forming space 99. For example, the tunneling film 390 may include an oxide such as silicon oxide.

[0088] The charge trapping film 380 may be conformally formed along the upper surface of the first interlayer insulating film 315a, the lower surface of the second interlayer insulating film 315b, and the follow-through film 390 (i.e., the sidewall of the semiconductor pattern 420). For example, the charge trapping film 380 may include a nitride such as a silicon nitride.

[0089] The barrier film 370 is conformally formed along the charge trapping film 380. That is, the barrier film 370 may be conformally formed along the charge trapping film 380 on the first interlayer insulating film 315a, the charge trapping film 380 in contact with the follow-through film 390, and the charge trapping film 380 under the second interlayer insulating film 315b. The barrier film 370 may include a metal oxide (e.g., aluminum oxide (Al2O3)).

[0090] The conductive film 485 is formed to contact the barrier film 370. The conductive film 485 does not completely fill the unit forming space 99, but only partially fills the unit forming space 99. Therefore, a portion of the barrier film 370 is exposed by the conductive film 485.

[0091] Specifically, through-holes 520 are formed that penetrate multiple interlayer insulating films 315a and 315b. The through-holes 520 can be, for example, holes used to form a common source line (CSL). The through-holes 520 and the cell forming spaces 99 not filled by the conductive film 485 are connected to each other.

[0092] refer to Figure 7 The barrier film 370 exposed by the conductive film 485 is removed by performing an atomic layer etching process.

[0093] Specifically, a pretreatment is performed on the substrate W. That is, a first plasma is formed in the chamber 100 using a first gas G1 containing chlorine, and a second plasma is formed in the chamber 100 using a second gas G2 containing oxygen.

[0094] Next, a precursor PC is provided into the chamber 100, causing the barrier film 370 exposed by the conductive film 485 to react with the precursor PC, thereby etching the barrier film 370 on an atomic level.

[0095] Next, by repeatedly performing the formation of the first plasma, the formation of the second plasma, and the provision of the precursor PC, the barrier film 370 exposed by the conductive film 485 is removed. As a result, as... Figure 7 As shown, a surface 485a of the conductive film 485 and a surface 370a of the barrier film 370 can be aligned with each other. A surface 485a of the conductive film 485 and a surface 370a of the barrier film 370 are exposed in the cell forming space 99.

[0096] The following is for reference Figure 8Table 1 illustrates the experimental results using substrate processing methods according to some embodiments of the present invention. Figure 8 This is a diagram illustrating experimental results using a substrate processing method according to some embodiments of the present invention.

[0097] First, referring to Table 1, the target layer includes aluminum oxide (Al2O3).

[0098] During the first plasma treatment ( Figure 2 S12), perform the second plasma processing ( Figure 2 S14) and perform thermal etching ( Figure 2 During S20, the temperature of the substrate is maintained at 200°C.

[0099] Regarding the execution of the first plasma treatment ( Figure 2 S12), a first gas (Cl2) is supplied into the chamber at a flow rate of 30 sccm and an inert gas (Ar) is supplied at a flow rate of 500 sccm (corresponding to S12). Figure 3 (t1~t2). A first plasma is generated using a first gas (Cl2). Then, an inert gas (Ar) (corresponding to...) is supplied into the chamber at a flow rate of 2000 sccm. Figure 3 (t2~t3), thereby expelling the byproducts inside the chamber.

[0100] Regarding the execution of the second plasma treatment ( Figure 2 S14), a second gas (O2) is supplied into the chamber at a flow rate of 30 sccm and an inert gas (Ar) is supplied at a flow rate of 500 sccm (corresponding to S14). Figure 3 (t3~t4). A second plasma is generated using a second gas (O2). Then, an inert gas (Ar) (corresponding to) is supplied into the chamber at a flow rate of 2000 sccm. Figure 3 (t4~t5), thereby expelling the byproducts inside the chamber.

[0101] Regarding the execution of thermal etching ( Figure 2 S20), a precursor (Hfac) and an inert gas (Ar) are mixed and supplied into the chamber at a flow rate of 25 sccm (corresponding to S20). Figure 3 (t5~t6). Next, inert gas (Ar) is supplied into the chamber at a flow rate of 2000 sccm (corresponding to t5~t6). Figure 3 (t6~t7), thereby expelling byproducts from inside the chamber.

[0102] By changing the substrate temperature to 250°C, 300°C, and 350°C, a first plasma treatment (S12), a second plasma treatment (S14), and a thermal etching (S20) were performed. Table 1 summarizes the above experimental conditions.

[0103] Table 1

[0104]

[0105] Based on the experimental conditions in Table 1, the results are as follows: Figure 8 As shown.

[0106] refer to Figure 8 The x-axis represents the substrate temperature (in °C), and the y-axis represents the etching depth (in °C). / cycle).

[0107] With the substrate temperature at 200°C, the etching amount per cycle (EPC) is: At a substrate temperature of 250°C, the etching amount per cycle is: With the substrate temperature at 300°C, the etching amount per cycle is: At a substrate temperature of 350°C, the etching amount per cycle is: As the substrate temperature increases, the amount of etching per cycle increases; as the substrate temperature decreases, the amount of etching per cycle decreases.

[0108] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, those skilled in the art should understand that the present invention can be implemented in other specific forms without changing its technical concept or essential features. Therefore, it should be understood that the embodiments described above are exemplary in all respects and not restrictive.

Claims

1. A substrate processing method, comprising the following steps: A substrate including the target layer is provided into the cavity; A first plasma is formed in the chamber using a first gas including chlorine to perform a first modification on the target layer; A second plasma is formed in the chamber using a second gas including oxygen to perform a second modification on the target layer that has undergone the first modification; A precursor is provided into the chamber to allow the target layer, which has undergone second modification, to react with the precursor. as well as The process of forming the first plasma, forming the second plasma, and providing the precursor is repeated to remove at least a portion of the target layer. The target layer comprises at least one of metal oxide, silicon oxide, silicon nitride, and titanium nitride. The precursor includes diketone gases.

2. The substrate processing method according to claim 1, wherein, During the formation of the first plasma, the substrate is controlled at a first temperature. During the formation of the second plasma, the substrate is controlled at a second temperature, and During the provision of the precursor, the substrate is controlled at a third temperature.

3. The substrate processing method according to claim 2, wherein, The first temperature and the second temperature are the same as each other.

4. The substrate processing method according to claim 2, wherein, The third temperature is higher than the first temperature and the second temperature.

5. The substrate processing method according to claim 2, wherein, The third temperature is above 50°C and below 400°C.

6. The substrate processing method according to claim 1, wherein, The precursor is selected from at least one of the group consisting of hexafluoroacetylacetone and acetylacetone.

7. The substrate processing method according to claim 1, wherein, The first gas is selected from at least one of the group consisting of Cl2, HCl, SiCl4, CCl4 and BCl3.

8. The substrate processing method according to claim 1, wherein, The second gas is selected from at least one of the group consisting of O2, H2O, N2O and O3.

9. The substrate processing method according to claim 1, wherein, The formation of the first plasma, the formation of the second plasma, and the provision of the precursor are performed in a dual-process chamber capable of simultaneously performing plasma processing and heat treatment.

10. A substrate processing method, comprising the following steps: A substrate having a semiconductor device formed thereon is introduced into a cavity. The semiconductor device includes: a first interlayer insulating film; a second interlayer insulating film formed on the first interlayer insulating film; a semiconductor pattern penetrating the first interlayer insulating film and the second interlayer insulating film; a charge trapping film conformally formed along the upper surface of the first interlayer insulating film, the lower surface of the second interlayer insulating film, and the sidewall of the semiconductor pattern; a barrier film conformally formed along the charge trapping film; and a conductive film formed to contact the barrier film, wherein a portion of the barrier film is exposed by the conductive film. A first plasma is formed in the chamber using a first gas including chlorine. A second plasma is formed in the chamber using a second gas including oxygen; A precursor is provided into the chamber to cause the barrier membrane exposed by the conductive membrane to react with the precursor; and The process of forming the first plasma, forming the second plasma, and providing the precursor is repeated to remove at least a portion of the barrier film exposed by the conductive film. The barrier film comprises a metal oxide. The precursor includes diketone gases.

11. The substrate processing method according to claim 10, wherein, The charge trapping membrane comprises nitrides.

12. The substrate processing method according to claim 10, wherein, During the formation of the first plasma, the substrate is controlled at a first temperature. During the formation of the second plasma, the substrate is controlled at a second temperature, and During the provision of the precursor, the substrate is controlled at a third temperature.

13. The substrate processing method according to claim 12, wherein, The third temperature is above 50°C and below 400°C.

14. A substrate processing apparatus, comprising: A heat source is located inside the cavity and is configured to heat the substrate; A gas supply system is configured to supply a first gas, a second gas, and a precursor to the chamber; An electrode system for generating plasma using the first gas or the second gas supplied to the chamber; as well as The controller is configured to control the heat source, the gas supply system, and the electrode system to perform atomic layer etching on a target layer of the substrate. The atomic layer etching includes the following steps: The first gas, comprising chlorine, is supplied into the chamber, and a first plasma is formed based on the first gas to perform a first modification on the target layer; The chamber is supplied with the second gas, which includes oxygen, and a second plasma is formed based on the second gas to perform a second modification on the target layer that has undergone the first modification. The precursor is provided into the chamber to allow the second-modified target layer to react with the precursor; and The process of forming the first plasma, forming the second plasma, and providing the precursor is repeated to remove at least a portion of the target layer. The target layer comprises at least one of metal oxide, silicon oxide, silicon nitride, and titanium nitride. The precursor includes diketone gases.

15. The substrate processing apparatus according to claim 14, wherein, The precursor is supplied from the side wall of the chamber, and The heat source is located on the upper surface of the chamber.

16. The substrate processing apparatus according to claim 14, wherein, The precursor is supplied from the upper surface of the chamber, and The heat source is located on the side wall of the chamber.

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