Substrate processing method and substrate processing apparatus

Abstract

A substrate processing method and a substrate processing apparatus capable of continuously controlling coverage of a film formed on a substrate are provided. The substrate processing method includes a) a process of exposing a substrate having a pattern formed on a front surface to a first reaction species in a chamber, and adsorbing the first reaction species on the front surface of the substrate. Further, the substrate processing method includes b) a process of exposing the substrate to plasma formed of a second reaction species in the chamber, and forming a film on the front surface of the substrate. Further, the substrate processing method includes c) a process of repeatedly executing the process including the process a) and the process b) two or more times in a manner of changing a residence amount of the first reaction species at the start of the process b).

Description

Technical Field

[0001] The present invention relates to a substrate processing method and a substrate processing device. Background Art

[0002] As a technology used in the manufacture of semiconductor devices, atomic layer deposition (ALD) is known. ALD is classified as one of the chemical vapor deposition (CVD) methods. CVD is a method of forming a film on a substrate by placing a substrate in a chamber, introducing a gas containing the components of the film to be formed into the chamber, and causing a chemical reaction on the front surface of the substrate or in the gas phase. Unlike CVD, ALD does not introduce multiple reaction gases into the chamber together. First, a first reaction gas (precursor) is introduced into the chamber so that it is adsorbed on the substrate, and the unadsorbed first reaction gas is discharged from the chamber. Next, a second reaction gas is introduced into the chamber so that it reacts with the components of the first reaction gas adsorbed on the substrate to form a film. ALD can control the film thickness at the atomic layer level by self-control, and is therefore used to form dense films.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: U.S. Patent Application Publication No. 2005 / 70041 Summary of the Invention

[0006] Technical problem to be solved by the invention

[0007] The present invention provides a technology capable of continuously controlling the coverage of a film formed on a substrate.

[0008] Technical solutions to technical problems

[0009] A substrate processing method implemented by a substrate processing apparatus according to one aspect of the present invention includes the steps of: a) exposing a substrate having a pattern formed on its front surface to a first reactive species within a chamber, causing the first reactive species to adsorb on the front surface of the substrate; b) exposing the substrate to a plasma formed from a second reactive species within the chamber, thereby forming a film on the front surface of the substrate; and c) repeating a process comprising steps a) and b) two or more times in a manner that varies the retention level of the first reactive species at the start of step b).

[0010] Effects of the Invention

[0011] According to the present invention, the coverage of a film formed on a substrate can be continuously controlled. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is a flowchart showing an example of the flow of the substrate processing method according to the first embodiment.

[0013] Figure 2A This is a flowchart showing the flow of Processing Example 1 performed by the substrate processing method according to the first embodiment.

[0014] Figure 2B This is a flowchart showing the flow of Processing Example 2 performed by the substrate processing method according to the first embodiment.

[0015] Figure 2C This is a flowchart showing the flow of Processing Example 3 performed by the substrate processing method according to the first embodiment.

[0016] Figure 2D This is a flowchart showing the flow of Processing Example 4 performed by the substrate processing method according to the first embodiment.

[0017] Figure 3A This is a diagram used to illustrate the relationship between film formation method and coverage.

[0018] Figure 3B is with Figure 3A Schematic longitudinal cross-sectional view of the patterns corresponding to (1) to (5).

[0019] Figure 4 A diagram illustrating chemical vapor deposition.

[0020] Figure 5 A diagram illustrating atomic layer deposition.

[0021] Figure 6 It is a diagram for explaining the mixing mode in the first embodiment.

[0022] Figure 7 This is a diagram showing an example of the structure of the substrate processing apparatus according to the first embodiment.

[0023] Figure 8 This is a diagram for explaining an example of processing conditions stored in the substrate processing apparatus according to the first embodiment.

[0024] Figure 9 This is a diagram for explaining an example of a process stored in the substrate processing apparatus according to the first embodiment.

[0025] Figure 10 It is a diagram showing experimental results of processing based on the substrate processing method of the first embodiment.

[0026] Figure 11 It will Figure 10The graph shown is a normalized graph of the experimental results.

[0027] Figure 12 It is a diagram showing an example of the structure of a substrate processing apparatus according to the second embodiment.

[0028] Figure 13 This is a diagram showing an example of the structure of information stored in the corresponding storage unit.

[0029] Figure 14A This is a diagram showing an example of low-frequency unevenness of a pattern formed on a substrate.

[0030] Figure 14B This is a diagram showing an example of the power spectrum density obtained by measuring a pattern formed on a substrate.

[0031] Figure 14C This is a diagram showing an example of high-frequency unevenness of a pattern formed on a substrate.

[0032] Figure 14D This is a diagram showing another example of the power spectrum density obtained by measuring the pattern formed on the substrate.

[0033] Figure 15 This is a flowchart showing an example of the flow of the substrate processing method according to the second embodiment.

[0034] Figure 16 This is a diagram showing an example of the configuration of a processing apparatus that performs substrate processing in the first and second embodiments.

[0035] Figure 17 This is a diagram showing an example of a processing system capable of executing the substrate processing in the first and second embodiments.

[0036] Description of Reference Numerals

[0037] 100, 100A substrate processing device

[0038] 110, 110A Storage unit

[0039] 111 Processing condition storage unit

[0040] 112 Processing and Storage Department

[0041] 113 Corresponding storage unit

[0042] 120, 120A control unit

[0043] 121 Selection Department

[0044] 122 Instruction Department

[0045] 123 Acquisition Department

[0046] 130 Input unit

[0047] 140 Output

[0048] 150 Ministry of Communications

[0049] 200 Processing Device

[0050] 300 measuring devices

[0051] NW Network. DETAILED DESCRIPTION

[0052] Hereinafter, with reference to the accompanying drawings, the disclosed embodiments are described in detail. This embodiment is not intended to be limiting. In addition, the various embodiments can be appropriately combined within the scope of not causing conflict in the processing content. In addition, in the various drawings, the same or corresponding parts are marked with the same reference numerals.

[0053] In addition, in the following description, "above" refers to the top direction of the processing device, that is, the front direction of the substrate arranged in the processing device. In addition, "below" refers to the bottom direction of the processing device, that is, the back direction of the substrate arranged in the processing device. In addition, in order to indicate a part of the pattern formed on the substrate, when "above" and "below" are used, "above" refers to the front side of the substrate, that is, the side that is the processing object of film formation and etching. "Below" refers to the back side of the substrate, that is, the side that is not the processing object of film formation or etching. In addition, the thickness direction of the substrate is referred to as the longitudinal direction, and the direction parallel to the front side of the substrate is referred to as the lateral direction.

[0054] In the following description, "reactive species" includes a gas containing the reactive species.

[0055] (First embodiment)

[0056] Figure 1 This is a flowchart showing an example of the process of the substrate processing method of the first embodiment. The substrate processing method of the first embodiment is performed, for example, by a substrate processing apparatus that controls a processing apparatus (eg, a chamber) that performs processes such as etching, film formation, and cleaning.

[0057] First, a substrate processing apparatus selects one or more processes to be performed continuously on a substrate (e.g., a semiconductor substrate formed of silicon) (step S11). Next, the substrate processing apparatus causes a processing apparatus to perform the selected process (step S12). When the process is completed, the process ends.

[0058] Here, "processing" includes one or more processes performed on a substrate. The one or more processes may be, for example, a film forming process, an etching process, a cleaning process, a temperature adjustment process, etc. In addition, "processing" includes information on the execution order of the one or more processes.

[0059] Figures 2A to 2D Each of the flowcharts shows the flow of processing examples 1 to 4 executed by the substrate processing method according to the first embodiment.

[0060] Figure 2A Processing Example 1 is a film formation process performed by CVD. First, a substrate processing apparatus reacts a first reactant with a second reactant in a chamber to form a film on the front surface of a substrate (step SA1). The substrate processing apparatus then terminates the process.

[0061] Figure 2B The processing example 2 shown is a film forming process performed by ALD (including the "mixed mode" described later). The processing of processing example 1 includes process a) and process b). In process a), the substrate processing device exposes the substrate with a pattern formed on the front to the first reactant in the chamber, so that the first reactant is adsorbed on the front of the substrate (step SB1). Then, in process b), the substrate processing device exposes the substrate to the plasma formed by the second reactant in the chamber, and forms a film on the front of the substrate (step SB2). The substrate processing device determines whether a specified number of cycles have been performed (step SB3). When it is determined that the specified number of cycles have not been performed (step SB3, no), the substrate processing device returns to step SB1 and repeats the process. On the other hand, when it is determined that the specified number of cycles have been performed (step SB3, yes), the substrate processing device ends the process.

[0062] In addition, if Figure 2B As shown, step a may include step a1 of adsorbing a first reactant species onto a substrate and step a2 of removing at least a portion of the first reactant species from the chamber. Similarly, step b may include step b1 of introducing a second reactant species into the chamber to form a plasma for film formation and step b2 of removing at least a portion of the second reactant species from the chamber.

[0063] Figure 2C Processing Example 3 shown is an etching process. First, the substrate processing apparatus performs etching (step SC1). Then, the substrate processing apparatus ends the process.

[0064] Figure 2DProcessing Example 4, shown here, combines film formation and etching processes under different conditions. Processing Example 4 sequentially executes the processes of Processing Example 1, Processing Example 2, and Processing Example 3. The substrate processing apparatus first executes Processing Example 1 (step SD1). Next, the substrate processing apparatus executes Processing Example 2 (step SD2). Subsequently, the substrate processing apparatus executes Processing Example 3 (step SD3). The substrate processing apparatus then terminates the process.

[0065] In addition, "processing" includes information on the processing conditions of each process. The information on the processing conditions includes, for example, the pressure in the chamber, the frequency and power of the radio frequency applied to generate plasma, the type and flow rate of the gas, the processing time, the temperature of each part of the chamber, etc. In addition, "processing" includes information on the number of times each process is performed and the number of times multiple processes are repeated in a predetermined order. For example, when Figures 2A to 2D In the case of executing multiple cycles in the processing example 2 shown, different processing conditions can be set for each cycle. The "processing" executed in the substrate processing method of the first embodiment includes, for example, one or more processes for forming a film with different coverage on a pattern having a height difference formed on the substrate.

[0066] In addition, "coverage" refers to the ratio of the film formed on the upper part of the pattern with a height difference formed on the substrate to the film formed on the lower part. Coverage refers to, for example, the ratio of the thickness of the film formed on the upper part of the inner periphery of the hole formed in the substrate to the thickness of the film formed on the lower part. In addition, for example, coverage refers to the ratio of the film thickness of the film formed on the front side of the substrate to the film thickness of the film formed on the bottom surface of the hole formed in the substrate. For example, in the film forming process using CVD, the film is mainly formed on the upper part of the pattern. In contrast, in the film forming process using ALD, the film is uniformly formed on the front side of the substrate regardless of the height difference of the pattern. As described above, the coverage varies depending on the method of the film forming process.

[0067] Figure 3A This is a diagram for explaining the relationship between the film formation method and the coverage. Figure 3A The horizontal axis of the graph represents the longitudinal position (also referred to herein as aspect ratio) of a pattern formed on a substrate, such as a hole. The vertical axis represents the thickness of a film formed on the pattern. For example, (1) represents a state in which the thickness of the film formed at a position with a low aspect ratio, i.e., the upper portion of the pattern, is large, and no film is formed at a position with a high aspect ratio, i.e., the lower portion of the pattern. In addition, (2) to (4) represent a state in which the thickness of the film formed gradually decreases from the upper portion to the lower portion of the pattern. In addition, (5) represents a state in which the thickness of the film formed from the upper portion to the lower portion of the pattern is approximately uniform.

[0068] Figure 3B is with Figure 3Aschematic longitudinal cross-sectional view of the pattern corresponding to (1) to (5) of FIG. 1. Figure 3B (1) is a state where the film F is formed only on the top Top of the pattern P. Figure 3B (2) to (4) of FIG. 1 are states where the film formation amount gradually changes from the top Top of the pattern P to the upper portion of the side wall SW and the lower portion of the side wall SW. Figure 3B (5) of FIG. 1 is a state where the film F having a substantially uniform thickness is formed on any of the top Top, the upper portion of the side wall SW, the lower portion of the side wall SW, and the bottom Bottom of the pattern P. Figure 3B (1) to (5) of FIG. 1 respectively correspond to Figure 3A (1) to (5) of FIG. 1 are substantially uniform.

[0069] Hereinafter, methods for achieving the coverage of Figure 3A and 3B (1) to (5) will be described.

[0070] Figure 4 is a diagram for explaining CVD. In CVD, a gas containing components that react with each other to form a film is introduced into a chamber in which a substrate is disposed, and a film is formed on the substrate by the reaction. In the case of Figure 4 , gas A and gas B are simultaneously introduced into a chamber in which a substrate Sub Figure 4 (A) is disposed. The reaction species in the introduced gas A react with the reaction species in the gas B, and a film Figure 4 (B) is formed on the substrate Sub. Since the components of the film that react in a gas phase are deposited from above, when there is a pattern having a difference in level on the substrate, the coverage of the film formed by CVD becomes a state where it decreases as it goes from the top of the pattern to the bottom. (Refer to Figure 4 (1) of FIG. 1. Figure 4 (1) of FIG. 1.

[0071] Figure 5 is a diagram for explaining ALD. In ALD, a first reaction species and a second reaction species are sequentially introduced into a chamber in which a substrate is disposed to form a film. In the case of Figure 5 , first, gas A (first reaction species) is introduced into a chamber Figure 5 (A) in which a substrate Sub Figure 5 (B) is disposed. The molecules in the gas A are adsorbed on the front surface Figure 5 (C) of the substrate Sub. When there is no more adsorption site, the molecules no longer deposit on the substrate Sub. The gas A remaining in the chamber is purged. Next, gas B (second reaction species) is introduced into the chamber Figure 5(D) in the figure). At this time, plasma can also be generated from gas B to promote the reaction. The molecules or radicals in gas B react with the molecules adsorbed on the substrate Sub to form a film. At this time, if all the molecules of gas A on the substrate Sub react with the molecules of gas B, the remaining molecules of gas B will remain in the chamber in the form of gas phase. Then, the retained gas B ( Figure 5 In this way, in ALD, a film is formed by performing four steps: adsorption, removal, reaction (e.g., oxidation), and removal. Since ALD forms a film in a self-controlled manner, the coverage of the film formed by ALD is such that a film thickness is formed from the top of the pattern to the bottom (see Figure 3A 、 Figure 3B (5)).

[0072] Figure 6 This figure illustrates the hybrid mode in the first embodiment. The "hybrid mode" in the first embodiment refers to a film formation method that combines ALD and CVD, using the same process flow as ALD and reacting the first reactant A and the second reactant B in the gas phase, similar to CVD.

[0073] exist Figure 6 In the example, first, gas A (first reactant) is introduced into the substrate Sub ( Figure 6 The molecules in the introduced gas A are adsorbed on the substrate Sub ( Figure 6 In the mixed mode, after the molecules are adsorbed onto the substrate Sub, the gas A is not completely purged from the chamber ( Figure 6 (C)). Then, while gas A remains in the chamber, gas B (second reactant) is introduced into the chamber ( Figure 6 (D) in the figure). The molecules in gas B react with the molecules of gas A adsorbed on the substrate Sub, and also react with the molecules of gas A in the gas phase in the chamber to form a film. Therefore, in addition to the self-controlled film formation of ALD, a film with the same coverage as CVD is formed ( Figure 6 (E) in FIG. 1 ). Gas A is, for example, a silicon-containing gas. Gas B is, for example, an oxygen-containing gas. Gas A may be, for example, a carbon-containing gas. Gas B may be, for example, a nitrogen-containing gas.

[0074] In hybrid film formation, when the second reactant is introduced into the chamber, the coverage can be varied by adjusting the amount of the first reactant remaining in the chamber (hereinafter referred to as the retention amount). Hybrid coverage can be adjusted using the following processing conditions.

[0075] (1) First reaction species removal process ( Figure 6 Processing time of step (C)

[0076] (2) Pressure in the chamber during the first reaction species removal process

[0077] (3) Flow rate of the purge gas used in the purge step of the first reactive species

[0078] (4) Dilution of the first reaction species ( Figure 6 Process (B)

[0079] Here, the time required to replace the gas in the chamber (hereinafter also referred to as residence time) can be expressed by the following formula (1).

[0080] T=(P×V) / (Q)……(1)

[0081] In the formula, T represents the residence time (seconds), that is, the time the gas stays in the processing space (chamber). P represents the pressure in the processing space (Torr). V represents the volume of the processing space (liters). Q represents the gas flow rate (sccm). According to formula (1), the residence time T is proportional to the volume and pressure of the processing space, and inversely proportional to the gas flow rate. Therefore, the larger the volume of the processing space and the higher the pressure, the longer the residence time, and the larger the gas flow rate, the shorter the residence time.

[0082] Therefore, the amount of the first reactive species remaining in the chamber when the second reactive species is introduced into the chamber can be increased by adjusting the processing conditions as follows.

[0083] (1) The treatment time of the first reaction species removal step is shortened (for example, by making it shorter than the residence time).

[0084] (2) Increasing the pressure in the chamber during the first reaction species removal step.

[0085] (3) Reduce the flow rate of the purge gas used in the purge step of the first reactive species.

[0086] Furthermore, without changing the treatment conditions in the purge step for the first reactive species, the retention of the first reactive species can be increased by increasing the dilution of the first reactive species (i.e., using the treatment condition (4)) to increase the amount of reactive molecules that remain without adsorption to the substrate. Furthermore, the retention of the first reactive species can be maintained by not providing a purge step.

[0087] As described above, in the substrate processing method of the first embodiment, continuous coverage control is achieved by combining film formation processes that achieve different coverages.

[0088] (An Example of the Structure of a Substrate Processing Apparatus)

[0089] Figure 7 1 is a diagram showing an example of the structure of the substrate processing apparatus 100 according to the first embodiment. The substrate processing apparatus 100 can be constituted by an information processing apparatus such as a personal computer (PC). The substrate processing apparatus 100 is connected to a processing apparatus 200 via a network NW.

[0090] The network NW may be, for example, the Internet, an intranet, a local area network, a wide area network, or a combination thereof. In addition, the network NW may be a wired network, a wireless network, or a combination thereof.

[0091] The processing device 200 includes a processing space (chamber) for performing processing on the substrate, and is capable of performing processing on the substrate. The details of the processing device 200 will be described later. However, the structure and type of the processing device 200 are not particularly limited. The processing device 200 can be, for example, a plasma processing device using any plasma source such as capacitively coupled plasma (CCP: Capacitively Coupled Plasma), inductively coupled plasma (ICP: Inductively Coupled Plasma), microwave plasma, etc. The processing device 200 performs film forming processing, etching processing, etc. such as atomic layer deposition (ALD: Atomic Layer Deposition) and chemical vapor deposition (CVD: Chemical Vapor Deposition). The processing device 200 can be a device that uses plasma when processing a substrate, or a device that does not use plasma.

[0092] The substrate processing apparatus 100 includes a storage unit 110 , a control unit 120 , an input unit 130 , an output unit 140 , and a communication unit 150 .

[0093] The storage unit 110 stores information used for processing in the substrate processing apparatus 100 and information generated as a result of the processing. The storage unit 110 includes, for example, a flash memory, a RAM (Random Access Memory), a ROM (Read Only Memory), a hard disk, an optical storage device, and the like.

[0094] The control unit 120 controls the operation and functions of the substrate processing apparatus 100. The control unit 120 is, for example, an integrated circuit or an electronic circuit and includes, for example, a CPU (Central Processing Unit) or an MPU (MicroProcessing Unit).

[0095] The input unit 130 receives information input from the outside to the substrate processing apparatus 100. The input unit 130 includes, for example, a touch panel, a mouse, a keyboard, a microphone, and peripheral circuits thereof.

[0096] The output unit 140 outputs information from the substrate processing apparatus 100. The output unit 140 includes, for example, a screen, a speaker, a printer, and peripheral circuits thereof.

[0097] The communication unit 150 enables communication with other devices via the network NW. The communication unit 150 includes, for example, a modem, a port, a router, and a switch.

[0098] (Information stored in the storage unit 110)

[0099] The storage unit 110 includes a processing condition storage unit 111 and a processing storage unit 112 .

[0100] The processing condition storage unit 111 stores processing conditions for processing on a substrate executed in the processing apparatus 200 , for example, processing conditions for film formation, etching, and the like.

[0101] Figure 8 This is a diagram for explaining an example of processing conditions stored in the substrate processing apparatus 100 according to the first embodiment. Figures 4 to 6 The processing conditions of each film forming process described. For example, in the case of CVD, the processing conditions include the pressure in the chamber, the frequency and power of the high frequency (HP) applied when generating plasma, the type of gas introduced into the chamber, the flow rate (ratio) of the gas, etc. The processing conditions also include the processing time and the set temperature of each part of the chamber. In addition, in the case of ALD and mixed mode, the processing conditions can be set separately for the adsorption process of the first reactant (process a1), the removal process of the first reactant (process a2), the reaction process of the second reactant (process b1), and the removal process of the second reactant (process b2). (Process a1), (process a2), (process b1), and (process b2) in Figure 2B Shown in.

[0102] exist Figure 8In the example, the processing conditions include "condition ID (Identifier)", "step number", "pressure", "high frequency (HP)", "gas", "flow rate", "processing time" and "temperature". "Condition ID" is an identifier that uniquely identifies each processing condition. "Step number" is a number that identifies each process when one process includes multiple processes. "Pressure" is the pressure value in the chamber during the process. "High frequency (HP)" is the frequency and power of the high frequency applied to the electrode in the chamber during the process. "Gas" is information that determines the gas introduced into the chamber during the process. "Flow rate" is the flow rate of the corresponding gas. "Processing time" indicates the time of the process. "Temperature" is the temperature of a specified part of the chamber set when performing the process.

[0103] For example, in Figure 8 In the data file, step numbers "1" to "4" are stored as process conditions identifiable by "Condition ID: P100." This indicates that the process conditions identified by condition ID "P100" include four steps. Furthermore, associated with "Step Number 1," "Pressure, XX mT," "Gas, X / Y," "Flow Rate, R1 / R2," "Processing Time, 2 seconds," and "Temperature, T1 / T2 / T3" are stored. This indicates that under the process conditions of condition ID "P100," in the step identified by step number "1," the chamber pressure is set to XX mT. Furthermore, in this step, gas X (here, an unspecified gas) and gas Y are supplied into the chamber at a flow rate ratio of R1 sccm to R2 sccm. Furthermore, the process time for this step is 2 seconds. Furthermore, during the execution of this step, the temperatures of the chamber's designated areas are set to T1, T2, and T3 degrees Celsius.

[0104] In addition, Figure 8 The processing conditions represented by the condition ID "P100" in the figure correspond to ALD. In the processing conditions of the condition ID "P100", step number "1" is the processing condition of the adsorption process (process a1), and step number "2" is the processing condition of the cleaning process (process a2) after the adsorption process. In addition, step number "3" is the processing condition of the reaction process (process b1), and step number "4" is the processing condition of the cleaning process (process b2) after the reaction process. In addition, in Figure 8 The processing condition indicated by the condition ID "P200" corresponds to CVD (refer to Figure 2A , step SA1). Since the processing of condition ID "P200" has only one process, only the processing condition of step number "1" is stored. Figure 8The processing conditions represented by condition IDs "P301" to "P303" correspond to the mixed mode. The processing conditions for condition IDs "P301" to "P303" are nearly identical to those for condition ID "P100," but the "processing time" for step number "2" is different. This is because the processing conditions for condition IDs "P301" to "P303" set the processing time for the purge step (step a2) to be shorter in order to implement the mixed mode.

[0105] The process storage unit 112 stores processes that are combinations of the process conditions stored in the process condition storage unit 111 .

[0106] Figure 9 1 is a diagram for explaining an example of processing stored in the substrate processing apparatus 100 according to the first embodiment. Figure 9 In the example, a process includes a "process ID," "number of iterations," and "condition ID / sequence." The "process ID" is an identifier that uniquely identifies a process. The "number of iterations" is the number of times a process is executed based on the corresponding processing conditions within that process. The "condition ID / sequence" indicates the processing conditions for the process executed within that process and, if multiple processes are executed, the order in which they are executed. Alternatively, the "condition ID / sequence" may be a process ID and sequence, rather than a condition ID and sequence.

[0107] For example, in Figure 9 In the example, "Number of cycles 1" and "Condition ID / Sequence P200" are stored in association with "Process ID S001." This indicates that, in the process identified by process ID S001, the process based on the process conditions identified by condition ID P200 is executed once. The process conditions identified by condition ID P200 are stored in the process condition storage unit 111. Specifically, the process conditions for condition ID P200 are chamber pressure "XXmT," high frequency (HP) "Z1MHz / Z2W," gas "X / Y," and flow rate "R1 / R2." Furthermore, the process time is "10 seconds," and the temperature is "T1 / T2 / T3."

[0108] For example, in Figure 9 In the example, "Number of cycles, 5" and "Condition ID / sequence, S001→S003→S100" are stored in association with the process ID "S500". This means that the process identified by the process ID "S500" is executed in sequence with the processes identified by the process IDs "S001", "S003", and "S100". In addition, it means that the three processes are repeated five times in sequence. The process identified by the process ID "S001" is CVD, and the process identified by the process ID "S003" is mixed mode (see Figure 8). In the case where the process identified by the process ID “S100” is etching, the process ID “S001” means that CVD, ALD, and etching are continuously and repeatedly performed five times.

[0109] (Structure and Function of Control Unit 120)

[0110] return Figure 7 , the structure and function of the control unit 120 will be described. The control unit 120 includes a selection unit 121 and an instruction unit 122.

[0111] The selection unit 121 receives an instruction input via the input unit 130 or the communication unit 150. Then, the selection unit 121 selects one or more processes ( Figure 1 , step S11). The selection unit 121 transmits the selected process to the instruction unit 122.

[0112] The instruction unit 122 instructs the processing device 200 to execute the process based on the process selected by the selection unit 121 ( Figure 1 , step S12).

[0113] (Experimental example)

[0114] Figure 10 It is a diagram showing experimental results of processing based on the substrate processing method of the first embodiment. Figure 10 (A) shows the process ID "S001" (refer to Figure 8 、 Figure 9 ) Coverage obtained when CVD is performed once during a period of 10 seconds. Figure 10 (B) shows the process ID "S002" (refer to Figure 8 、 Figure 9 ) Coverage obtained when the process is executed 40 times with the clear time set to 0.5 seconds in hybrid mode. Figure 10 (C) shows the process ID "S003" (refer to Figure 8 、 Figure 9 ) Coverage obtained when the process is executed 70 times with the clear time set to 0.7 seconds in hybrid mode. Figure 10 (D) shows the process ID "S004" (refer to Figure 8 、 Figure 9 ) Coverage obtained when the process is executed 105 times with the clear time set to 1 second in mixed mode. Figure 10 (E) shows the process ID "S005" (refer to Figure 8 、 Figure 9 ) Coverage obtained when ALD is executed 200 times.

[0115] Furthermore, the difference between the processing conditions of condition IDs “P301”, “P302”, “P303”, and “P100” lies only in the length of the purge time of the first reaction species. Figure 10 In (B), the purge time is 0.5 seconds, (C) is 0.7 seconds, (D) is 1 second, and (E) is 10 seconds. The purge time is gradually extended from (B) to (E). Figure 10 In the example of oxygen-containing gas) when the first reactant species ( Figure 10 The retention rate of the X-containing gas (in the example shown in FIG2 ) decreases from (B) to (E). Therefore, the film formation rate in CVD mode is the highest in (B), and decreases from (C) to (D). Furthermore, in (E), film formation is performed in ALD mode.

[0116] exist Figure 10 In the example (A), the film is formed almost entirely on the upper portion of the pattern, and is hardly formed on the lower portion. Figure 10 Under the treatment conditions of (A), the Figure 3B (1) Considerable coverage.

[0117] exist Figure 10 In the example of (B), the film thickness gradually decreases from the upper part of the pattern to the lower part, and almost no film is formed in the lower part of the pattern. Figure 10 (B) under the treatment conditions, the results were basically the same as those of Figure 3B The coverage of (2).

[0118] exist Figure 10 In the example of (C), the thickness of the film formed is increased as a whole compared to (B), and similarly to (B), the film thickness decreases from the upper part to the lower part. Figure 10 (C) basically corresponds to Figure 3B The coverage of (3).

[0119] exist Figure 10 In the example of (D), the film thickness of the formed film is further increased compared to (C), and film formation is also observed at the bottom of the pattern. Figure 10 (D) is basically the same as Figure 3B The coverage rate corresponding to (4).

[0120] exist Figure 10 In the example of (E), the thickness of the film formed is almost the same between the upper and lower parts of the pattern, and the film formation is substantially the same. Figure 10 Under the treatment conditions of (E), the equivalent Figure 3B The coverage of (5).

[0121] also, Figure 10 The "depth" in the graph is the distance (size) from the top to the bottom of the film formed on the side wall. That is, the "depth" is the size excluding the top and bottom (equivalent to Figure 10 Dimension represented by D1 in FIG. 1 ). In addition, “D / A” refers to the thickness of the film formed on the side wall.

[0122] Figure 11 It will Figure 10 The curve graph is obtained by normalizing the experimental results shown. Figure 11 As can be seen, the coverage gradually changes between (A) and (E), achieving an intermediate film formation mode between CVD and ALD. As described above, according to the substrate processing method of the first embodiment, the coverage can be continuously changed to achieve film formation with a desired coverage.

[0123] Furthermore, ALD does not necessarily need to form a conformal film. For example, the adsorption of the first reactant species can be restricted to the upper portion of the pattern, allowing film formation only there. Alternatively, the process can be terminated before the second reactant species reaches the bottom of the pattern, allowing film formation only on the upper portion. Using subconformal ALD allows for more flexible control of coverage.

[0124] (Effects of the First Embodiment)

[0125] As described above, the substrate processing method of the first embodiment includes steps a), b), and c. Step a) is a step of exposing a substrate having a pattern formed on its front surface to a first reactive species within a chamber, causing the first reactive species to adsorb on the front surface of the substrate. Step b) is a step of exposing the substrate to a plasma formed from a second reactive species within a chamber, thereby forming a film on the front surface of the substrate. Step c) is a step of repeatedly performing the treatment including steps a) and b) two or more times in a manner that changes the retention amount of the first reactive species at the start of step b). Therefore, according to the substrate processing method of the first embodiment, the coverage of the film formed on the substrate can be continuously controlled. For example, the greater the retention amount of the first reactive species at the start of step b), the thicker the film formed on the upper portion of the pattern becomes than the thickness of the film formed on the lower portion of the pattern. On the other hand, the smaller the retention amount of the first reactive species at the start of step b), the closer the thickness of the film formed on the upper portion of the pattern becomes to the thickness of the film formed on the lower portion of the pattern. Therefore, according to the substrate processing method of the first embodiment, the coverage of the film formed on the substrate can be continuously controlled based on the retention amount of the first reaction species at the start of step b).

[0126] Further, in the substrate processing method of the first embodiment, the amount of the first reaction species remaining at the start of the process b) can be changed by controlling the amount of the first reaction species introduced into the chamber in the process a). Further, in the substrate processing method of the first embodiment, the amount of the first reaction species remaining at the start of the process b) can be changed by controlling the dilution of the first reaction species introduced into the chamber in the process a). Thus, according to the first embodiment, by adjusting the amount and dilution of the first reaction species, the coverage of the film formed on the substrate can be easily controlled.

[0127] Further, in the substrate processing method of the first embodiment, the process a) can include: al) a process of introducing the first reaction species into the chamber; and a2) a process of removing at least a part of the first reaction species from the chamber. Further, in the substrate processing method of the first embodiment, the amount of the first reaction species remaining at the start of the process b) can be changed by controlling the amount of the first reaction species removed in the process a2). Thus, according to the first embodiment, it is also possible to adjust the amount of the first reaction species in the chamber in the removal process. Thus, according to the first embodiment, by simply adjusting the processing conditions, the coverage of the film formed on the substrate can be continuously controlled. Further, according to the first embodiment, by changing the processing conditions of the removal process, an intermediate film formation mode between ALD and CVD can be easily realized.

[0128] Further, in the substrate processing method of the first embodiment, the amount of the first reaction species removed in the process a2) can be changed by changing at least one of the pressure in the chamber, the processing time, and the flow rate of the removal gas, thereby changing the amount of the first reaction species remaining at the start of the process b). Thus, according to the first embodiment, by selecting and adjusting the easily controllable conditions from among the plurality of processing conditions, the coverage of the film formed on the substrate can be controlled.

[0129] Further, in the substrate processing method of the first embodiment, the process a) or the process b) can be ended before the reaction on the front surface of the substrate is saturated. Thus, in the substrate processing method of the first embodiment, the coverage of the film formed on the substrate can be further finely adjusted using the sub-conformal ALD.

[0130] In addition, the substrate processing method of the first embodiment may further include: d) after performing step c), a step of etching the substrate using the film formed by step c) as a mask. In addition, in the substrate processing method of the first embodiment, step c) may be repeatedly performed until the shape of the pattern satisfies a predetermined condition. In addition, the method may further include: e) a step of repeatedly performing the process including step c) and step d) two or more times. Therefore, according to the first embodiment, etching can be performed after continuously controlling the coverage to correct the shape of the mask. Therefore, according to the first embodiment, etching accuracy can be improved. In addition, according to the first embodiment, the shape of the mask can be corrected and etching can be performed.

[0131] Furthermore, in the substrate processing method of the first embodiment, step c) can be performed in the same chamber. Therefore, according to the first embodiment, processing productivity can be further improved. Furthermore, when the substrate processing method of the first embodiment includes step d), steps c) and d) can be performed in the same chamber or in different chambers. Therefore, according to the first embodiment, film formation time and etching time can be balanced, and the overall substrate processing can be optimized.

[0132] Furthermore, in the substrate processing method of the first embodiment, step c) can be performed by setting the pressure within the chamber to approximately 10 to 200 mTorr. Although lowering the pressure shortens the residence time, the hybrid mode of the first embodiment can be achieved by adjusting other processing conditions. Therefore, according to the first embodiment, it is possible to suppress increases in processing time and improve substrate processing productivity.

[0133] In addition, the substrate processing apparatus of the first embodiment includes a selection unit and an indication unit. The selection unit selects a plurality of processes. The processes include, for example, process a), process b), and process c. Process a) is a process of exposing a substrate having a pattern formed on the front surface to a first reactant in a chamber, so that the first reactant is adsorbed on the front surface of the substrate. Process b) is a process of exposing the substrate to a plasma formed by a second reactant in a chamber, so that a film is formed on the front surface of the substrate. Process c) is a process of repeatedly performing the processes including process a) and process b) two or more times in a manner that changes the retention amount of the first reactant at the start of process b). In process c), the retention amounts of the first reactant at the start of process b) for the plurality of processes selected by the selection unit are different from each other. The indication unit indicates that the plurality of processes selected by the selection unit are to be performed in the chamber. Therefore, according to the substrate processing apparatus of the first embodiment, the coverage of the film formed on the substrate can be continuously controlled.

[0134] (Second embodiment)

[0135] The substrate processing apparatus of the first embodiment sets a processing condition in advance and selects a processing in accordance with a desired coverage. The substrate processing apparatus of the second embodiment selects and performs a processing in accordance with a state of a pattern on a substrate. The substrate processing method of the second embodiment selects and performs a processing in accordance with, for example, a degree of unevenness of a pattern on a substrate.

[0136] Figure 12 is a view showing one example of a configuration of the substrate processing apparatus 100A of the second embodiment. The configuration of the substrate processing apparatus 100A of the second embodiment is substantially the same as that of the substrate processing apparatus 100 of the first embodiment. However, the substrate processing apparatus 100A differs from the substrate processing apparatus 100 in that the substrate processing apparatus 100A has a correspondence storage section 113 and an acquisition section 123. In addition, the substrate processing apparatus 100A differs from the substrate processing apparatus 100 in that the substrate processing apparatus 100A is communicably connected to the measurement apparatus 300 via a network NW. For the configuration of the substrate processing apparatus 100A that is the same as that of the substrate processing apparatus 100, the description thereof is omitted and the different configuration is described below.

[0137] The substrate processing apparatus 100A is communicably connected to the processing apparatus 200 and the measurement apparatus 300 via the network NW. The network NW and the processing apparatus 200 are the same as those of the first embodiment (refer to Figure 7 ).

[0138] The measurement apparatus 300 measures a shape of a pattern formed on a substrate and outputs a value indicating the shape. Hereinafter, the value output by the measurement apparatus 300 is also referred to as a measurement value. The kind of the measurement value output by the measurement apparatus 300 is not particularly limited. The measurement value may, for example, be an aspect ratio of a pattern formed on a substrate. In addition, the measurement value may, for example, be a standard deviation of a signal waveform indicating unevenness of a pattern formed on a substrate. In addition, the measurement value may, for example, be a power spectral density (PSD) of a signal waveform indicating unevenness of a pattern formed on a substrate. In addition, even in a case where standard deviations are the same in spite of a complete difference in a period of unevenness, the power spectral density is preferably used as the measurement value in order to improve measurement accuracy (refer to Chris A. Mack, “Reducing roughness in extreme ultraviolet lithography” in Journal of Micro / Nanolithography, MEMS, and MOEMS, 17(4), 041006 (2018)). In the second embodiment, it is preferable that the measurement value at least include the aspect ratio and the power spectral density.

[0139] For example, the measuring device 300 may be a device that derives the standard deviation of the pattern shape, the power spectrum density, etc. based on information and images obtained by analyzing the pattern formed on the substrate using a scanning electron microscope (SEM). Figure 12 In the example, the substrate processing apparatus 100A and the measuring apparatus 300 are connected via the network NW. However, instead of connecting the measuring apparatus 300 to the substrate processing apparatus 100A, an operator or the like may input measurement values ​​derived by other means into the substrate processing apparatus 100A.

[0140] The substrate processing apparatus 100A includes a storage section 110A, a control section 120A, an input section 130 , an output section 140 , and a communication section 150 .

[0141] In addition to the processing condition storage unit 111 and the processing storage unit 112 similar to those of the first embodiment, the storage unit 110A further includes a correspondence storage unit 113. The correspondence storage unit 113 stores the correspondence relationship between the measurement values ​​input from the measurement device 300 and the processing.

[0142] Figure 13 113 is a diagram showing an example of the structure of information stored in the corresponding storage unit 113. Figure 13 In the example, the corresponding storage unit 113 stores "device ID," "measurement value, aspect ratio, PSD," and "processing ID." "Device ID" is information that identifies the device formed by the process. Furthermore, "device ID" may be information indicating target values ​​for aspect ratio and PSD. "Measurement value, aspect ratio" indicates the aspect ratio of a pattern obtained by measuring a pattern formed on a substrate. "Measurement value, PSD" indicates the power spectral density of the pattern obtained by measuring a pattern formed on a substrate. "Processing ID" indicates the process applied to the pattern corresponding to the "measurement value" to implement the corresponding "device ID."

[0143] Figures 14A to 14D It is a diagram for explaining the relationship between power spectral density and pattern shape. Figure 14A This is a diagram showing an example of low-frequency unevenness of a pattern formed on a substrate. Figure 14B This is a diagram showing an example of the power spectrum density obtained by measuring a pattern formed on a substrate.

[0144] Here, low-frequency unevenness refers to unevenness that appears with a relatively larger period than high-frequency unevenness, that is, concavity and convexity; high-frequency unevenness refers to unevenness that appears with a relatively smaller period than low-frequency unevenness.

[0145] Figure 14A(1) shows a state in which a line and space pattern that should be formed in a straight line has unevenness and an undulating shape. Figure 14A This is the state of observing the pattern from top to bottom. Figure 14A In the example (1), the intervals between the lines are different at X1 and X2. Figure 14A The power spectrum density obtained from the pattern of (1) can be expressed as Figure 14B (1). Figure 14B The horizontal axis of the graph represents frequency (unit: nanometer nm), and the vertical axis represents power spectral density (unit: nm 3 ), that is, the energy of each frequency band. Figure 14B In the curve graph, the closer to the right side of the horizontal axis, the more unevenness is generated by a small period, that is, the more high-frequency unevenness is generated, and the closer to the left side, the more unevenness is generated by a large period, that is, the more low-frequency unevenness is generated.

[0146] Here, improve Figure 14A (1) The unevenness of the pattern is smoothed by trimming the concave and convex parts ( Figure 14A (2)). In Figure 14A In the example of (2), the intervals between the lines are uniform, while the interval X1 in (1) has approximately the same interval X3 as the other parts. This also changes the shape of the power spectrum density graph. Figure 14B (2) is an example of the power spectrum density obtained by measuring the improved uneven pattern. Figure 14B In (2), it is shown that low-frequency unevenness, i.e., unevenness occurring with a large period, is improved and the pattern surface is flattened.

[0147] Figure 14C This is a diagram showing an example of high-frequency unevenness of a pattern formed on a substrate. Figure 14D This is a diagram showing another example of the power spectrum density obtained by measuring the pattern formed on the substrate.

[0148] When the electron spectral density is expressed as Figure 14C When the high frequency uneven pattern shown in (1) is Figure 14D As shown in (1). At this time, improve Figure 14C (1) The unevenness of the pattern is smoothed by trimming the concave and convex parts ( Figure 14C (2)). In this way, the shape of the curve graph is as follows Figure 14D (2) changes as follows. Figure 14D From (2), it can be seen that the high-frequency unevenness is more improved than the low-frequency unevenness, and the pattern surface is flattened.

[0149] Figure 14BThe low-frequency unevenness shown can be flattened by, for example, CVD. Since a film formed by CVD tends to be deposited in larger voids, the larger concave portions of the low-frequency unevenness are filled.

[0150] On the other hand, regarding Figure 14D The high-frequency unevenness shown here shows that the recessed areas that cause the unevenness are relatively small when viewed across the entire pattern. Therefore, CVD film formation cannot preferentially fill these recessed areas. Therefore, a hybrid method combining ALD and CVD is preferred to improve high-frequency unevenness.

[0151] In the substrate processing method of the second embodiment, the shape of unevenness, etc., of the pattern on the substrate being processed is measured before processing is performed, and processing conditions, or treatments, to be applied are selected based on the measured values. Thus, a treatment can be selected based on the shape abnormalities occurring in the pattern on the substrate, allowing the pattern shape to be corrected.

[0152] In the above, an example of selecting either CVD or a hybrid mode based on the unevenness of the pattern on the substrate is given, but the substrate processing method of the second embodiment is not limited to this. For example, a first threshold value and a second threshold value greater than the first threshold value are pre-set based on the shape of the unevenness of the pattern on the substrate to be processed. In one example, the first threshold value is set to the upper limit value at which the unevenness of the pattern on the substrate can be flattened by CVD, and the second threshold value is set to the lower limit value at which the unevenness of the pattern on the substrate can be flattened by ALD. Then, before performing the treatment or after performing the treatment a specified number of times, the shape of the unevenness of the pattern on the substrate to be processed is measured, and the measured value, the first threshold value, and the second threshold value are compared. When the measured value is below the first threshold value, CVD is selected as the film forming treatment. When the measured value is greater than the first threshold value and less than the second threshold value, the above-mentioned hybrid mode is selected as the film forming treatment. When the measured value is greater than the second threshold value, ALD is selected as the film forming treatment. Then, the unevenness of the pattern on the substrate is improved by the selected film forming treatment.

[0153] return Figure 12 Next, the substrate processing apparatus 100A according to the second embodiment will be described. In addition to the selection unit 121 and the instruction unit 122 similar to those of the first embodiment, the control unit 120A further includes an acquisition unit 123 .

[0154] The acquisition unit 123 acquires measurement values ​​from the measurement device 300 or the like via the input unit 130 and / or the communication unit 150. The measurement values ​​acquired by the acquisition unit 123 include the aspect ratio and the power spectrum density described above.

[0155] Figure 15is a flowchart showing an example of a process of the substrate processing method of the second embodiment. First, the acquisition unit 123 acquires the measurement value of the pattern formed on the substrate as the processing object (step S21). In addition, the acquisition unit 123 acquires the target value of the pattern to be formed on the substrate as the processing object, for example, the device ID. Next, the selection unit 121 refers to the corresponding storage unit 113 and selects the processing corresponding to the acquired target value and measurement value (step S22). The selection unit 121 sends the selected processing to the indication unit 122. The indication unit 122 instructs the processing device 200 to perform the processing based on the processing received from the selection unit 121 (step S23). At this point, the processing ends.

[0156] Furthermore, the substrate processing apparatus 100 or 100A may repeatedly perform the above-described process on one substrate. For example, each time the operation of a process is completed, the substrate processing apparatus 100 or 100A may select and perform the next process.

[0157] Furthermore, in the second embodiment, the correspondence table stored in the correspondence storage unit 113 may be appropriately updated based on the processing results in the processing apparatus 200. For example, the measurement apparatus 300 may obtain measurement values ​​representing the shape of the pattern on the substrate before and after processing. For example, each time processing in the processing apparatus 200 is completed, the measurement apparatus 300 may measure the state of the pattern on the substrate and transmit the measurement value to the substrate processing apparatus 100A. The substrate processing apparatus 100A may then update the correspondence table based on the difference between the measured value after processing and the target value. Furthermore, the substrate processing apparatus 100A may generate the correspondence table through machine learning based on the measured values ​​and target values ​​of the pattern on the substrate before and after processing.

[0158] (Effects of the Second Embodiment)

[0159] As described above, the substrate processing method of the second embodiment further includes: a step of measuring a value representing the shape of a pattern on the front surface of the substrate before performing processing; and a step of selecting processing conditions based on the measured value. Furthermore, processing is performed under the selected processing conditions. For example, the substrate processing apparatus performs a cleaning step under the selected processing conditions. Therefore, according to the second embodiment, the substrate processing apparatus can select a processing to be performed based on the shape of the pattern on the substrate. Therefore, the substrate processing apparatus can select and execute processing to achieve a coverage ratio corresponding to the state of the pattern on the substrate.

[0160] Furthermore, the substrate processing method of the second embodiment may also include a step of measuring a value representing the shape of a pattern on the front surface of the substrate after the process has been executed a predetermined number of times. Furthermore, the substrate processing method of the second embodiment includes a step of selecting processing conditions for the next process to be executed based on the difference between the value measured before the process was executed and the value measured after the process was executed a predetermined number of times. Therefore, according to the second embodiment, the next process can be selected after evaluating the process performance.

[0161] Furthermore, the substrate processing method of the second embodiment may further include a step of etching the substrate using the film formed on the front surface of the substrate as a mask, and the film formation and etching steps may be repeated two or more times. In this case, the film formation and etching steps may be performed in the same chamber or in different chambers.

[0162] (An Example of Processing Device 200 According to One Embodiment)

[0163] Figure 16 1 is a diagram showing an example of the configuration of a processing apparatus 200 for executing substrate processing according to the first and second embodiments. Figure 16 1 shows a schematic cross section of the processing device 200. In addition, Figure 16 The processing apparatus 200 shown is a parallel plate type plasma processing apparatus. However, the processing apparatus that can perform the substrate processing in the first embodiment and the second embodiment is not limited to the processing apparatus shown in the figure.

[0164] The processing apparatus 200 includes an airtight chamber 12. The chamber 12 has a generally cylindrical shape, and defines a processing space S in which plasma is generated as its internal space. The processing apparatus 200 is provided with a mounting table 13 within the chamber 12. The upper surface of the mounting table 13 is formed as a mounting surface 54d capable of mounting a wafer W as a processed object. In this embodiment, the mounting table 13 includes a base 14 and an electrostatic chuck 50. The base 14 has a generally circular plate shape and is disposed below the processing space S. The substrate 14 is made of, for example, aluminum and functions as a lower electrode.

[0165] Electrostatic chuck 50 is disposed on the upper surface of susceptor 14. The upper surface of electrostatic chuck 50 is flat, disc-shaped, and corresponds to a mounting surface 54d on which wafer W can be mounted. Electrostatic chuck 50 includes an electrode 54a and an insulator 54b. Electrode 54a is disposed within insulator 54b and is connected to a DC power supply 56 via a switch SW. Application of a DC voltage from DC power supply 56 to electrode 54a generates a Coulomb force, which attracts and holds wafer W on electrostatic chuck 50. Electrostatic chuck 50 also includes a heater 54c within insulator 54b. Heater 54c heats electrostatic chuck 50 by supplying electrical energy from a power supply mechanism (not shown). This allows the temperature of mounting table 13 and wafer W to be controlled.

[0166] In this embodiment, the processing device 200 further includes a cylindrical holding portion 16 and a cylindrical support portion 17. The cylindrical holding portion 16 is connected to the edges of the side and bottom surfaces of the susceptor 14 and holds the susceptor 14. The cylindrical support portion 17 extends vertically from the bottom of the chamber 12 and supports the susceptor 14 via the cylindrical holding portion 16.

[0167] A focus ring 18 is provided on the upper surface of the peripheral portion of the susceptor 14. The focus ring 18 is a component for improving the in-plane uniformity of the processing accuracy of the wafer W. The focus ring 18 is a plate-like component having a substantially annular shape and is made of, for example, silicon, quartz, or silicon carbide.

[0168] In this embodiment, an exhaust passage 20 is formed between the side wall of the chamber 12 and the cylindrical support portion 17. A baffle 22 is installed at the entrance of the exhaust passage 20 or in the middle of it. In addition, an exhaust port 24 is provided at the bottom of the exhaust passage 20. The exhaust port 24 is defined by an exhaust pipe 28 embedded in the bottom of the chamber 12. An exhaust device 26 is connected to the exhaust pipe 28. The exhaust device 26 has a vacuum pump, and by operating the vacuum pump, the processing space S in the chamber 12 can be decompressed to a specified vacuum level. Thus, the processing space S in the chamber 12 is maintained in a vacuum atmosphere. The processing space S is an example of a vacuum space. A gate valve 30 for opening and closing the inlet and outlet of the wafer W is installed on the side wall of the chamber 12.

[0169] The high-frequency power supply 32 is electrically connected to the susceptor 14 via a matching unit 34. The high-frequency power supply 32 is a power source for generating plasma, applying high-frequency power of a predetermined high frequency (e.g., 13 MHz) to the lower electrode, or susceptor 14. Furthermore, a refrigerant flow path (not shown) is formed within the susceptor 14. The processing apparatus 200 cools the mounting table 13 by circulating a refrigerant through the refrigerant flow path. This allows the temperature of the mounting table 13 and the wafer W to be controlled.

[0170] The processing apparatus 200 is further provided with a shower head 38 in the chamber 12 . The shower head 38 is disposed above the processing space S. The shower head 38 includes an electrode plate 40 and an electrode support 42 .

[0171] The electrode plate 40 is a conductive plate having a generally circular shape and constitutes the upper electrode. The high-frequency power supply 35 is electrically connected to the electrode plate 40 via the matching box 36. The high-frequency power supply 35 is a power source for generating plasma and applies high-frequency power energy of a predetermined high frequency (e.g., 60 MHz) to the electrode plate 40. When high-frequency power is applied to the susceptor 14 and the electrode plate 40 by the high-frequency power supply 32 and the high-frequency power supply 35, respectively, a high-frequency electric field is formed in the space between the susceptor 14 and the electrode plate 40, i.e., the processing space S, generating plasma.

[0172] A plurality of vent holes 40h are formed on the electrode plate 40. The electrode plate 40 is detachably supported by the electrode support 42. A buffer chamber 42a is provided inside the electrode support 42. The processing device 200 also includes a gas supply unit 44, which is connected to the gas inlet 25 of the buffer chamber 42a via a gas supply conduit 46. The gas supply unit 44 supplies processing gas to the processing space S. The processing gas can be, for example, a processing gas for etching, or a processing gas for film formation. A plurality of holes respectively connected to the plurality of vent holes 40h are formed on the electrode support 42, and the plurality of holes are connected to the buffer chamber 42a. The gas supplied from the gas supply unit 44 is supplied to the processing space S via the buffer chamber 42a and the vent holes 40h.

[0173] In this embodiment, a magnetic field forming mechanism 48 extending annularly or concentrically is provided at the top of the chamber 12. The magnetic field forming mechanism 48 facilitates high-frequency discharge (plasma ignition) in the processing space S and stably maintains the discharge.

[0174] In this embodiment, processing apparatus 200 further includes a gas supply line 58 and a heat transfer gas supply unit 62. Heat transfer gas supply unit 62 is connected to gas supply line 58. Gas supply line 58 extends to the upper surface of electrostatic chuck 50 and extends in a loop thereon. Heat transfer gas supply unit 62 supplies a heat transfer gas, such as He gas, between the upper surface of electrostatic chuck 50 and wafer W.

[0175] The processing apparatus 200 having the above-described structure is generally controlled by a control unit 90. The control unit 90 includes a process controller 91 having a CPU (Central Processing Unit) for controlling various components of the processing apparatus 200, a user interface 92, and a storage unit 93. In this embodiment, the control unit 90 may also be provided within the substrate processing apparatus 100 or 100A.

[0176] The user interface 92 includes a keyboard for the process manager to input commands for managing the processing apparatus 200 , a display for visually displaying the operating status of the processing apparatus 200 , and the like.

[0177] The storage unit 93 stores recipes such as control programs (software) and processing condition data. These control programs (software) are used to implement various processes executed by the processing device 200 under the control of the processing controller 91. Therefore, as needed, any recipe can be called from the storage unit 93 according to instructions from the user interface 92 and executed by the processing controller 91, thereby enabling the processing device 200 to perform the desired process under the control of the processing controller 91. Furthermore, recipes such as control programs and processing condition data can also be used in a state stored in a computer-readable computer storage medium (e.g., a hard disk, CD, floppy disk, semiconductor memory, etc.). Furthermore, recipes such as control programs and processing condition data can also be transmitted in real time from another device via, for example, a dedicated line and used online.

[0178] Figure 17 This is a diagram showing an example of a processing system that can be used to perform substrate processing in the first and second embodiments.

[0179] The processing system 1000 shown in FIG3 includes a control unit Cnt, a workbench 1122a, a workbench 1122b, a workbench 1122c, a workbench 1122d, a storage container 1124a, a storage container 1124b, a storage container 1124c, a storage container 1124d, a loading unit LM, a load lock chamber LL1, a load lock chamber LL2, a transfer chamber 1121, and a plasma processing apparatus 1010. The plasma processing apparatus 1010 may be, for example, Figure 16 The processing device 200 is shown.

[0180] The control unit Cnt is a computer including a processor, a storage unit, an input device, a display device, etc., and can control each unit of the processing system 1 described later. The control unit Cnt is connected to the conveying robot Rb1, the conveying robot Rb2, the optical observation device OC, the plasma processing device 1010, etc. The control unit Cnt can also serve as Figure 7 and Figure 12 The control units 120 and 120A of the substrate processing apparatus 100 and 100A shown in FIG. Figure 16 The control unit 90 of the processing apparatus 200 is shown. Alternatively, the control unit Cnt may be the substrate processing apparatus 100 or 100A.

[0181] The control unit Cnt operates according to a computer program (a program based on an input recipe) for controlling each component of the processing system 1000, issuing control signals. Based on the control signals from the control unit Cnt, each component of the processing system 1000, such as the transport robots Rb1 and Rb2, the optical observation device OC, and each component of the plasma processing apparatus 1010, is controlled. In the plasma processing apparatus 1010, the selection and flow rate of gas from the gas supply unit 44, the exhaust of the exhaust device 26, the power supply from the high-frequency power supplies 32 and 35, the power supply to the heater 54c, and the refrigerant flow rate and temperature can be controlled based on the control signals from the control unit Cnt. Furthermore, the various steps of the substrate processing methods of the first and second embodiments described above can be executed by operating the various components of the processing system 1000 under the control of the control unit Cnt. The computer programs for executing the substrate processing methods of the first and second embodiments described above, as well as various data used for executing the methods, are readable and stored in the storage unit of the control unit Cnt.

[0182] The work tables 1122a to 1122d are arranged along one side of the loader unit LM. Storage containers 1124a to 1124d are provided on each of the work tables 1122a to 1122d, respectively. Wafers W can be stored in the storage containers 1124a to 1124d.

[0183] A transfer robot Rb1 is provided in the loader unit LM. The transfer robot Rb1 takes out a wafer W stored in any of the storage containers 1124a to 1124d and transfers the wafer W to the load lock chamber LL1 or LL2.

[0184] The load lock chambers LL1 and LL2 are provided along the other side of the loading unit LM and are connected to the loading unit LM. The load lock chambers LL1 and LL2 constitute pre-decompression chambers. The load lock chambers LL1 and LL2 are connected to the transfer chamber 1121, respectively.

[0185] The transfer chamber 1121 is a chamber capable of reducing pressure, and a transfer robot Rb2 is provided in the transfer chamber 1121. The plasma processing apparatus 1010 is connected to the transfer chamber 1121. The transfer robot Rb2 removes a wafer W from the load lock chamber LL1 or the load lock chamber LL2 and transfers the wafer W to the plasma processing apparatus 1010.

[0186] The processing system 1000 includes an optical observation device OC. The wafer W can be moved between the optical observation device OC and the plasma processing device 1010 using the conveying robot Rb1 and the conveying robot Rb2. After the conveying robot Rb1 is moved to accommodate the wafer W in the optical observation device OC and the position of the wafer W is aligned in the optical observation device OC, the optical observation device OC measures the groove width of the pattern of the mask, etc. of the wafer W and sends the measurement result to the control unit Cnt. The optical observation device OC can measure the groove width of the pattern of the mask, etc. formed in multiple areas on the front surface of the wafer W. The measurement result of the optical observation device OC is used as the "measurement value" in the second embodiment (see Figure 15 ).

[0187] The embodiments disclosed herein are to be considered in all respects as illustrative and not restrictive. The above embodiments may be omitted, replaced, or modified in various forms without departing from the scope and spirit of the appended claims.

Claims

1. A substrate processing method, characterized in that: include: a) exposing a substrate having a pattern formed on the front surface thereof to a first reactive species in a chamber, so that the first reactive species is adsorbed on the front surface of the pattern; b) exposing the substrate to plasma formed by a second reactive species in the chamber to form a film on the front surface of the pattern; and c) Repeating the treatments a) and b) for the substrate two or more times in a manner that changes the retention amount of the first reaction species at the start of b).

2. The substrate processing method according to claim 1, wherein: In the above step a), the amount of the first reactant species introduced into the chamber is controlled to change the retention amount of the first reactant species at the start of step b).

3. The substrate processing method according to claim 1 or 2, wherein: In step a), the retention amount of the first reactant at the start of step b) is changed by controlling the dilution of the first reactant introduced into the chamber.

4. The substrate processing method according to claim 1 or 2, wherein: The above a) includes: a1) introducing the first reactant into the chamber; and a2) a step of removing a portion of the first reaction species from the chamber.

5. The substrate processing method according to claim 4, wherein: By controlling the amount of the first reaction species removed in a2), the retention amount of the first reaction species at the start of b) is changed.

6. The substrate processing method according to claim 5, wherein: The amount of the first reactive species purged in a2) is changed by changing at least one of the pressure in the chamber, the processing time, and the flow rate of the purge gas, thereby changing the retention amount of the first reactive species at the start of b).

7. The substrate processing method according to claim 1 or 2, wherein: Before the reaction on the front side of the substrate reaches saturation, the above a) or b) is completed.

8. The substrate processing method according to claim 1 or 2, wherein: The retention amount of the first reaction species at the start of step b) is controlled so that the thickness of the film formed on the upper portion of the pattern is thicker than the thickness of the film formed on the lower portion of the pattern.

9. The substrate processing method according to claim 1 or 2, wherein: The retention amount of the first reaction species at the start of step b) is controlled so that the thickness of the film formed on the upper portion of the pattern becomes close to the thickness of the film formed on the lower portion of the pattern.

10. The substrate processing method according to claim 1 or 2, wherein: The method further includes the step of d) etching the substrate using the film formed in c) as a mask.

11. The substrate processing method according to claim 10, wherein: The method further includes the step e) of repeatedly performing the treatments including the steps c) and d) two or more times.

12. The substrate processing method according to claim 1 or 2, wherein: Also includes: The step of measuring a value representing the shape of the pattern on the front surface of the substrate before performing a); and The process of selecting processing conditions based on the measured values, The steps a), b) and c) are performed under the selected processing conditions.

13. The substrate processing method according to claim 12, wherein: Also includes: a step of measuring a value representing the shape of the pattern on the front surface of the substrate after executing c) a predetermined number of times; and A step of selecting a processing condition for a process to be performed next based on a difference between a value measured before performing a) and a value measured after performing c) a predetermined number of times.

14. The substrate processing method according to claim 1 or 2, wherein: Step c) is repeatedly performed until the shape of the pattern meets a predetermined condition.

15. The substrate processing method according to claim 1 or 2, wherein: c) is performed in the same chamber.

16. The substrate processing method according to claim 1 or 2, wherein: The pressure in the chamber is set to 10 mTorr-200 mTorr, and step c) is performed.

17. A substrate processing method, characterized in that: include: f) a step of measuring a value representing the shape of the pattern on the front surface of the substrate; g) comparing the value with a predetermined first threshold and a second threshold greater than the first threshold; h) selecting a film forming process step based on the comparison result; and i) forming a film on the front surface of the substrate by the selected film forming process, In h), when the value is below the first threshold, CVD (chemical vapor deposition) is selected as the film forming process; when the value is greater than the first threshold and less than the second threshold, the substrate processing method described in any one of claims 1 to 16 is selected as the film forming process; when the value is greater than the second threshold, ALD (atomic layer deposition) is selected as the film forming process.

18. A substrate processing device, characterized in that: include: Select a selection section for multiple processing; and an instruction unit for instructing execution of the plurality of processes selected by the selection unit in the chamber, The treatment includes: a) exposing a substrate having a pattern formed on the front surface to a first reactant in the chamber, so that the first reactant is adsorbed on the front surface of the pattern; b) exposing the substrate to a plasma formed by a second reactant in the chamber, so as to form a film on the front surface of the pattern; and c) repeatedly performing the treatments of a) and b) on the substrate more than twice in a manner so as to change the retention amount of the first reactant at the beginning of b), and in c), the retention amounts of the first reactant at the beginning of b) are different from each other.

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