JP7531351B2 - SUBSTRATE PROCESSING METHOD, SUBSTRATE PROCESSING APPARATUS, AND SUBSTRATE PROCESSING SYSTEM - Google Patents

Description

The following disclosure relates to a substrate processing method , a substrate processing apparatus , and a substrate processing system .

Atomic Layer Deposition (ALD) is known as one of the techniques used in the manufacture of semiconductor devices. ALD is classified as a type of chemical vapor deposition (CVD). CVD is a technique in which a substrate is placed in a chamber, and then a gas containing the components of the film to be formed is introduced into the chamber, and a chemical reaction occurs on the surface of the substrate or in the gas phase to form a film on the substrate. Unlike CVD, ALD does not introduce multiple reaction gases into the chamber at once. First, a first reaction gas (precursor) is introduced into the chamber and adsorbed onto the substrate, and the first reaction gas that is not adsorbed is exhausted from the chamber. Next, a second reaction gas is introduced into the chamber and reacts with the components of the first reaction gas adsorbed on the substrate to form a film. ALD is used for forming dense films because it can control the film thickness at the atomic layer level by utilizing its self-regulating properties.

US Patent Application Publication No. 2005/70041

This disclosure provides a technology that allows for continuous control of the coverage of a film formed on a substrate.

According to one aspect of the present disclosure, a substrate processing method realized by a substrate processing apparatus includes a) exposing a substrate having a pattern formed on its surface to a first reactive species in a chamber, thereby adsorbing the first reactive species to the surface of the substrate. The substrate processing method also includes b) exposing the substrate to a plasma formed from a second reactive species in the chamber, thereby forming a film on the surface of the substrate. The substrate processing method also includes c) repeating the process including steps a) and b) two or more times by changing the amount of the first reactive species remaining at the start of step b).

This disclosure allows for continuous control of the coverage of the film formed on the substrate.

FIG. 1 is a flowchart showing an example of the flow of a substrate processing method according to a first embodiment. FIG. 2A is a flowchart showing a procedure of a processing example 1 performed by the substrate processing method according to the first embodiment. FIG. 2B is a flowchart showing a flow of a processing example 2 performed by the substrate processing method according to the first embodiment. FIG. 2C is a flowchart showing a flow of a processing example 3 performed by the substrate processing method according to the first embodiment. FIG. 2D is a flowchart showing a flow of Process Example 4 performed by the substrate processing method according to the first embodiment. FIG. 3A is a diagram for explaining the relationship between the film formation technique and the coverage. FIG. 3B is a schematic vertical cross-sectional view of the patterns corresponding to (1) to (5) in FIG. 3A. FIG. 4 is a diagram for explaining chemical vapor deposition. FIG. 5 is a diagram for explaining atomic layer deposition. FIG. 6 is a diagram for explaining the mixed mode in the first embodiment. FIG. 7 is a diagram showing an example of the configuration of the substrate processing apparatus according to the first embodiment. FIG. 8 is a diagram for explaining an example of processing conditions stored in the substrate processing apparatus according to the first embodiment. FIG. 9 is a diagram for explaining an example of a process stored in the substrate processing apparatus according to the first embodiment. FIG. 10 is a diagram showing experimental results of processing based on the substrate processing method according to the first embodiment. FIG. 11 is a graph showing the normalized experimental results shown in FIG. FIG. 12 is a diagram showing an example of the configuration of a substrate processing apparatus according to the second embodiment. FIG. 13 is a diagram illustrating an example of a configuration of information stored in the correspondence storage unit. FIG. 14A is a diagram showing an example of low-frequency roughness of a pattern formed on a substrate. FIG. 14B is a diagram showing an example of a power spectrum density obtained by measuring a pattern formed on a substrate. FIG. 14C is a diagram showing an example of high-frequency roughness of a pattern formed on a substrate. FIG. 14D is a diagram showing another example of the power spectral density obtained by measuring a pattern formed on a substrate. FIG. 15 is a flowchart showing an example of the flow of the substrate processing method according to the second embodiment. FIG. 16 is a diagram showing an example of the configuration of a processing apparatus for performing substrate processing in the first and second embodiments. FIG. 17 is a diagram showing an example of a processing system that can be used to perform substrate processing in the first and second embodiments.

The disclosed embodiments are described in detail below with reference to the drawings. Note that the present embodiments are not limiting. In addition, the embodiments can be appropriately combined as long as the processing contents are not inconsistent. Note that the same reference numerals are used in each drawing to denote the same or equivalent parts.

In the following description, "upper" refers to the direction toward the ceiling of the processing apparatus, i.e., the direction toward the surface of the substrate placed inside the processing apparatus. "Lower" refers to the direction toward the floor of the processing apparatus, i.e., the direction toward the back surface of the substrate placed inside the processing apparatus. When using "upper" and "lower" to indicate the portions of a pattern formed on a substrate, "upper" refers to the substrate surface side, i.e., the side that is the subject of processing such as film deposition or etching, and "lower" refers to the substrate back side, i.e., the side that is not the subject of processing such as film deposition or etching. The thickness direction of the substrate is also called the vertical direction, and the direction parallel to the substrate surface is also called the horizontal direction.

In the following description, "reactive species" includes gases that contain reactive species.

First Embodiment
1 is a flow chart showing an example of the flow of a substrate processing method according to a first embodiment. The substrate processing method according to the first embodiment is performed by a substrate processing apparatus that controls a processing apparatus (e.g., a chamber) in which processing such as etching, film formation, cleaning, etc. is performed.

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

Here, "processing" includes one or more processes performed on a substrate. The one or more processes are, for example, a film formation process, an etching process, a cleaning process, a temperature adjustment process, etc. Furthermore, "processing" includes information on the order in which the one or more processes are performed.

Figures 2A to 2D are flowcharts showing the flow of processing examples 1 to 4, respectively, performed by the substrate processing method according to the first embodiment.

Processing example 1 shown in FIG. 2A is a film formation process using CVD. First, the substrate processing apparatus reacts a first reactive species with a second reactive species in a chamber to form a film on the surface of a substrate (step SA1). Then, the substrate processing apparatus ends the process.

Processing example 2 shown in FIG. 2B is a film formation process by ALD (including the "mixed mode" described later). The process of processing example 1 includes steps a) and b). In step a), the substrate processing apparatus exposes a substrate having a pattern formed on its surface to a first reactive species in a chamber, and adsorbs the first reactive species onto the surface of the substrate (step SB1). Next, in step b), the substrate processing apparatus exposes the substrate to plasma formed from a second reactive species in the chamber, and forms a film on the surface of the substrate (step SB2). The substrate processing apparatus determines whether or not a predetermined number of cycles have been performed (step SB3). If it is determined that the predetermined number of cycles have not been performed (step SB3, No), the substrate processing apparatus returns to step SB1 and repeats the process. On the other hand, if it is determined that the predetermined number of cycles have been performed (step SB3, Yes), the substrate processing apparatus ends the process.

As shown in FIG. 2B, step a may include step a1 of adsorbing a first reactive species onto a substrate, and step a2 of purging at least a portion of the first reactive species from the chamber. Similarly, step b may include step b1 of introducing a second reactive species into the chamber to form a plasma and deposit a film, and step b2 of purging at least a portion of the second reactive species from the chamber.

Processing example 3 shown in FIG. 2C is an etching process. First, the substrate processing apparatus performs etching (step SC1). Then, the substrate processing apparatus ends the process.

Processing example 4 shown in FIG. 2D is a process that combines a film formation process and etching under different conditions. Processing example 4 is a process that sequentially executes the processes of processing examples 1, 2, and 3. The substrate processing apparatus first executes processing example 1 (step SD1). Next, the substrate processing apparatus executes processing example 2 (step SD2). Next, the substrate processing apparatus executes processing example 3 (step SD3). The substrate processing apparatus then ends the process.

The "processing" also includes information on the processing conditions of each process. The information on processing conditions includes, for example, the pressure inside the chamber, the frequency and power of the radio frequency (RF) applied to generate plasma, the type and flow rate of gas, the processing time, and the temperature of each part of the chamber. The "processing" also 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 multiple cycles are performed in the processing example 2 shown in Figures 2A to 2D, different processing conditions can be set for each cycle. The "processing" performed in the substrate processing method according to the first embodiment includes, for example, one or more processes that achieve film formation with different coverages on a pattern having height differences formed on a substrate.

Here, "coverage" refers to the ratio of the film formed on the top of a pattern having height differences formed on a substrate to the film formed on the bottom. Coverage, for example, refers to the ratio of the film thickness formed on the inner upper part of a hole formed in a substrate to the film thickness formed on the bottom. Also, for example, coverage refers to the ratio of the film thickness formed on the substrate surface to the film thickness formed on the bottom surface of a hole formed in a substrate. For example, in a film formation process using CVD, a film is formed mainly on the top of a pattern. In contrast, in a film formation process using ALD, a film is formed uniformly on the substrate surface regardless of the height differences of the pattern. In this way, coverage changes depending on the film formation process technique.

Figure 3A is a diagram for explaining the relationship between the film formation technique and coverage. The horizontal axis of the graph in Figure 3A indicates the vertical position (also called the aspect ratio here) in a pattern, such as a hole, formed on a substrate. The vertical axis indicates the film thickness of the film formed on the pattern. For example, (1) indicates a state in which the film formed at a low aspect ratio position, i.e., the upper part of the pattern, is thick, and no film is formed at a high aspect ratio position, i.e., the lower part of the pattern. Also, (2) to (4) indicate a state in which the film thickness gradually decreases from the top to the bottom of the pattern. Also, (5) indicates a state in which the film formed at the top to the bottom of the pattern is approximately uniform in thickness.

Figure 3B is a schematic vertical cross-sectional view of the patterns corresponding to (1) to (5) in Figure 3A. (1) in Figure 3B shows a state in which a film F is formed only on the top of the pattern P. (2) to (4) in Figure 3B show a state in which the amount of film formed gradually changes from the top of the pattern P to the upper part of the sidewall SW and the lower part of the sidewall SW. (5) in Figure 3B shows a state in which a film F of approximately uniform thickness is formed on the top, upper part, lower part, and bottom of the pattern P. (1) to (5) in Figure 3B roughly correspond to (1) to (5) in Figure 3A, respectively.

Next, we will explain each method for achieving the coverage (1) to (5) in Figures 3A and 3B.

Figure 4 is a diagram for explaining CVD. In CVD, gases containing components that react with each other to form a film are introduced into a chamber in which a substrate is placed, and a film is formed on the substrate by the reaction. In the example of Figure 4, gas A and gas B are simultaneously introduced into a chamber in which a substrate Sub (Figure 4 (A)) is placed. The reactive species in the introduced gas A react with the reactive species in gas B to form a film on the substrate Sub (Figure 4 (B)). Since the components of the film that react in the gas phase are deposited from above, if there is a pattern with height differences on the substrate, the coverage of the film formed by CVD decreases from the top to the bottom of the pattern (see Figures 4A and 4B (1)).

Figure 5 is a diagram for explaining ALD. In ALD, a first reactive species and a second reactive species are introduced in sequence into a chamber in which a substrate is placed to form a film. In the example of Figure 5, gas A (first reactive species) is first introduced (Figure 5(B)) into a chamber in which a substrate Sub (Figure 5(A)) is placed. Molecules in gas A are adsorbed onto the surface of the substrate Sub (Figure 5(C)). When there are no more adsorbing sites, the molecules do not deposit any more on the substrate Sub. Gas A remaining in the chamber is purged. Next, gas B (second reactive species) is introduced into the chamber (Figure 5(D)). At this time, plasma may be generated from gas B to promote the reaction. Molecules or radicals in gas B react with molecules adsorbed on the substrate Sub to form a film. At this time, when all the molecules of gas A on the substrate Sub have reacted with the molecules in gas B, the remaining molecules in gas B remain in the chamber in the gas phase. The remaining gas B is then purged (Figure 5 (E)). In this way, ALD forms a film by performing four processes: adsorption, purging, reaction (e.g., oxidation), and purging. Since ALD achieves film formation in a self-regulating manner, the coverage of the film formed by ALD is approximately constant from the top to the bottom of the pattern (see Figures 3A and 3B (5)).

Figure 6 is a diagram for explaining the mixed mode in the first embodiment. The "mixed mode" in the first embodiment is a film formation method that uses a process flow similar to ALD, while causing a reaction between a first reactive species A and a second reactive species B in a gas phase state, similar to CVD, in other words, a combination of ALD and CVD.

In the example of FIG. 6, first, gas A (first reactive species) is introduced into a chamber in which a substrate Sub (FIG. 6A) is placed. The molecules in the introduced gas A are adsorbed onto the substrate Sub (FIG. 6B). In the mixed mode, after the molecules are adsorbed onto the substrate Sub, gas A is not completely purged from the chamber (FIG. 6C). Then, gas B (second reactive species) is introduced into the chamber while gas A remains in the chamber (FIG. 6D). The molecules in gas B react with the molecules of gas A adsorbed onto the substrate Sub, and at the same time, they also react with the molecules of gas A present in the gas phase in the chamber to form a film. Therefore, in addition to the self-regulating film formation of ALD, a film with the same coverage as CVD is formed (FIG. 6E). Note that gas A is, for example, a silicon-containing gas. Gas B is, for example, an oxygen-containing gas. In addition, gas A can be, for example, a carbon-containing gas. Gas B can be, for example, a nitrogen-containing gas.

In the mixed mode deposition, the coverage can be changed by adjusting the amount of the first reactive species remaining in the chamber when the second reactive species is introduced into the chamber (hereinafter, also referred to as the retention amount). The coverage in the mixed mode can be adjusted by the following process conditions.
(1) Processing time of the first reactant purge step (step (C) in FIG. 6 ); (2) Pressure in the chamber in the first reactant purge step; (3) Flow rate of the purge gas used in the first reactant purge step; (4) Dilution degree of the first reactant (step (B) in FIG. 6 ).

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).
T=(P×V)/(Q)...(1)
In the formula, T represents the residence time (seconds), i.e., the time that the gas resides 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). As can be seen from 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 higher the gas flow rate, the shorter the residence time.

Therefore, the amount of the first reactant remaining in the chamber when the second reactant is introduced into the chamber can be increased by adjusting the process conditions as follows.
(1) The processing time of the purge step of the first reactive species is shortened (for example, shorter than the residence time).
(2) The pressure in the chamber is increased in the first reactant purge step.
(3) The flow rate of the purge gas used in the first reactant purge step is reduced.

In addition, if the processing conditions in the purging step of the first reactive species are not changed, the amount of the first reactive species remaining can also be increased by increasing the dilution degree of the first reactive species (processing condition (4) above) to increase the amount of reactive molecules that remain without adsorbing to the substrate. In addition, the amount of the first reactive species remaining can also be maintained without providing a purging step.

In this way, the substrate processing method according to the first embodiment achieves continuous coverage control by combining film formation processes that achieve different coverages.

(Example of the configuration of the substrate processing apparatus)
7 is a diagram showing an example of a configuration of the substrate processing apparatus 100 according to the first embodiment. The substrate processing apparatus 100 can be configured 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.

The network NW may be, for example, the Internet, an intranet, a local area network, a wide area network, or a combination thereof. The network NW may also be a wired network, a wireless network, or a combination thereof.

The processing apparatus 200 includes a processing space (chamber) in which processing of the substrate is performed, and performs processing of the substrate. Details of the processing apparatus 200 will be described later. However, the configuration and type of the processing apparatus 200 are not particularly limited. The processing apparatus 200 may be, for example, a plasma processing apparatus using any plasma source such as capacitively coupled plasma (CCP), inductively coupled plasma (ICP), or microwave plasma. The processing apparatus 200 performs film formation processes such as atomic layer deposition (ALD) and chemical vapor deposition (CVD), etching processes, and the like. The processing apparatus 200 may be an apparatus that uses plasma in processing the substrate, or an apparatus that does not use plasma.

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

The storage unit 110 stores information used in 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, etc.

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. The control unit 120 includes, for example, a CPU (Central Processing Unit), an MPU (Micro Processing Unit), etc.

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.

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 their peripheral circuits.

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

(Information stored in storage unit 110)
The storage unit 110 includes a processing condition storage unit 111 and a processing storage unit 112 .

The processing condition storage unit 111 stores the processing conditions for processing of substrates performed in the processing device 200, such as film formation, etching, etc.

FIG. 8 is a diagram for explaining an example of the processing conditions stored in the substrate processing apparatus 100 according to the first embodiment. The processing conditions are, for example, the processing conditions of each film formation process described with reference to FIG. 4 to FIG. 6. For example, in the case of CVD, the processing conditions include the pressure inside the chamber, the frequency and power of the high frequency (HP) applied during plasma generation, the type of gas introduced into the chamber, the gas flow rate (ratio), and the like. 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 may be set for each of the adsorption process of the first reactive species (process a1), the purging process of the first reactive species (process a2), the reaction process of the second reactive species (process b1), and the purging process of the second reactive species (process b2). (Process a1), (Process a2), (Process b1), and (Process b2) are illustrated in FIG. 2B.

In the example of FIG. 8, the process 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 process condition. "Step Number" is a number that identifies each process when one process includes multiple steps. "Pressure" is the pressure value in the chamber in the process. "High Frequency (HP)" is the frequency and power of the high frequency applied to the electrodes in the chamber in the process. "Gas" is information that identifies the gas introduced into the chamber in 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 that is set when the process is performed.

For example, in FIG. 8, step numbers "1" to "4" are stored as the process conditions identified by "Condition ID: P100". This indicates that the process conditions identified by condition ID "P100" include four processes. Also, in association with "Step Number, 1", "Pressure, XXmT", "Gas, X/Y", "Flow Rate, R1/R2", "Process Time, 2 sec", and "Temperature, T1/T2/T3" are stored. This indicates that in the process conditions of condition ID "P100", in the process identified by step number "1", the chamber pressure is set to XXmT. Also, in this process, X gas (here meaning an unspecified gas) and Y gas are supplied into the chamber at a flow rate ratio of R1 sccm to R2 sccm. Also, it indicates that the process time of this process is 2 seconds. Also, it indicates that during the execution of this process, the temperature of a specific part of the chamber is set to T1 degrees Celsius, T2 degrees Celsius, and T3 degrees Celsius.

In FIG. 8, the process condition indicated by condition ID "P100" corresponds to ALD. In the process condition of condition ID "P100", step number "1" is the process condition of the adsorption process (step a1), and step number "2" is the process condition of the purge process (step a2) after the adsorption process. In addition, step number "3" is the process condition of the reaction process (step b1), and step number "4" is the process condition of the purge process (step b2) after the reaction process. In addition, in FIG. 8, the process condition indicated by condition ID "P200" corresponds to CVD (see FIG. 2A, step SA1). Since the process of condition ID "P200" has one process, only the process condition of step number "1" is stored. In addition, in FIG. 8, the process conditions indicated by condition IDs "P301" to "P303" correspond to the mixed mode. The processing conditions for condition IDs "P301" to "P303" are almost the same as the processing conditions 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" have a short processing time for the purge process (process a2) to achieve mixed mode.

The processing storage unit 112 stores processing, which is a combination of processing conditions stored in the processing condition storage unit 111.

Figure 9 is a diagram for explaining an example of a process stored in the substrate processing apparatus 100 according to the first embodiment. In the example of Figure 9, the process includes a "process ID", a "cycle number", and a "condition ID/sequence". The "process ID" is an identifier that uniquely identifies the process. The "cycle number" is the number of times the process is executed based on the corresponding process conditions in the process. The "condition ID/sequence" is the process condition of the process executed in the process, and the sequence in which the processes are executed when multiple processes are executed. Note that the "condition ID/sequence" may be information on the process ID and sequence instead of the condition ID and sequence.

For example, in the example of FIG. 9, "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", a process based on the process condition identified by condition ID "P200" is executed once. The process condition identified by condition ID "P200" is stored in the process condition storage unit 111. That is, the process conditions for condition ID "P200" are chamber pressure "XXmT", high frequency (HP) "Z1MHz/Z2W", gas "X/Y", flow rate "R1/R2", process time "10sec", and temperature "T1/T2/T3".

For example, in the example of FIG. 9, "Number of cycles, 5" and "Condition ID/sequence, S001 ⇒ S003 ⇒ S100" are stored in association with process ID "S500". This indicates that the process identified by process ID "S500" executes processes identified by process IDs "S001", "S003", and "S100" in that order. It also indicates that the three processes are executed in sequence five times. The process identified by process ID "S001" is CVD, and the process identified by process ID "S003" is mixed mode (see FIG. 8). If the process identified by process ID "S100" is etching, then process ID "S001" means that CVD, ALD, and etching are executed five times in succession.

(Configuration and Functions of Control Unit 120)
7, the following describes the configuration and functions of the control unit 120. The control unit 120 includes a selection unit 121 and an instruction unit 122.

The selection unit 121 receives an instruction input via the input unit 130 or the communication unit 150. The selection unit 121 then selects one or more processes corresponding to the received instruction from the storage unit 110 ( FIG. 1 , step S11). The selection unit 121 passes the selected process to the instruction unit 122.

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

(Experimental Example)
10A and 10B are diagrams showing experimental results of processing based on the substrate processing method according to the first embodiment. FIG. 10A shows the coverage obtained when CVD was performed once for 10 seconds based on the processing ID "S001" (see FIGS. 8 and 9). FIG. 10B shows the coverage obtained when processing was performed 40 times in the mixed mode with the purge time set to 0.5 seconds based on the processing ID "S002" (see FIGS. 8 and 9). FIG. 10C shows the coverage obtained when processing was performed 70 times in the mixed mode with the purge time set to 0.7 seconds based on the processing ID "S003" (see FIGS. 8 and 9). FIG. 10D shows the coverage obtained when processing was performed 105 times in the mixed mode with the purge time set to 1 second based on the processing ID "S004" (see FIGS. 8 and 9). FIG. 10E shows the coverage obtained when ALD was performed 200 times based on the process ID "S005" (see FIGS. 8 and 9).

The only difference between the process conditions with condition IDs "P301", "P302", "P303", and "P100" is the length of the purge time for the first reactive species. In FIG. 10, (B) has a purge time of 0.5 seconds, (C) has a purge time of 0.7 seconds, (D) has a purge time of 1 second, and (E) has a purge time of 10 seconds. The purge time is gradually increased from (B) to (E). Therefore, the amount of the first reactive species (X-containing gas in the example of FIG. 10) remaining when the second reactive species (oxygen-containing gas in the example of FIG. 10) is introduced into the chamber decreases from (B) to (E). Therefore, it is considered that the amount of film formed in the CVD mode is the largest in (B), and the amount of film formed in the CVD mode decreases from (C) to (D). It is also considered that film formation is performed in the ALD mode in (E).

In the example of FIG. 10(A), the film is mostly formed on the upper part of the pattern, and almost none is formed on the lower part. In other words, under the processing conditions of FIG. 10(A), coverage equivalent to FIG. 3B(1) is achieved.

In the example of FIG. 10B, the film thickness gradually decreases from the top to the bottom of the pattern, and there is almost no film formation at the bottom of the pattern. In other words, under the processing conditions of FIG. 10B, coverage roughly corresponding to FIG. 3B (2) is achieved.

In the example of FIG. 10(C), the overall thickness of the film formed is greater than that of FIG. 10(B), but like FIG. 10(B), the thickness decreases from top to bottom. In other words, FIG. 10(C) can be said to be a coverage that roughly corresponds to FIG. 3B(3).

In the example of FIG. 10(D), the thickness of the film formed is even greater than in (C), and film formation is observed even at the bottom of the pattern. FIG. 10(D) can be said to have coverage roughly corresponding to FIG. 3B(4).

In the example of FIG. 10(E), the difference in the thickness of the film formed between the top and bottom of the pattern is almost eliminated, and a nearly uniform film is formed. In other words, under the processing conditions of FIG. 10(E), a coverage equivalent to FIG. 3B(5) is achieved.

In the graph of FIG. 10, "Depth" refers to the distance (dimension) from the top to the bottom of the film formed on the side wall. In other words, "Depth" is a dimension that does not include the top and bottom (corresponding to the dimension indicated by D1 in FIG. 10). Also, "D/A" refers to the thickness of the film formed on the side wall.

Figure 11 is a graph of the normalized experimental results shown in Figure 10. As can be seen from Figure 11, the coverage gradually changes between (A) and (E), and a film formation mode intermediate between CVD and ALD is achieved. In this way, according to the substrate processing method of the first embodiment, it is possible to continuously change the coverage and achieve film formation with the desired coverage.

Note that ALD does not necessarily have to form a conformal film. For example, the adsorption position of the first reactive species may be limited to the top of the pattern, and a film may be formed only on the top of the pattern. Also, a film may be formed only on the top of the pattern by terminating the process before the second reactive species reaches the bottom of the pattern. By using sub-conformal ALD, coverage can be controlled more flexibly.

(Effects of the First Embodiment)
As described above, the substrate processing method according to the first embodiment includes steps a), b), and c). Step a) is a step of exposing a substrate having a pattern formed on its surface to a first reactive species in a chamber, thereby adsorbing the first reactive species on the surface of the substrate. Step b) is a step of exposing the substrate to a plasma formed from a second reactive species in a chamber, thereby forming a film on the surface of the substrate. Step c) is a step of repeating the process including steps a) and b) two or more times by changing the amount of the first reactive species remaining at the start of step b). Therefore, according to the substrate processing method according to the first embodiment, the coverage of the film formed on the substrate can be continuously controlled. For example, the greater the amount of the first reactive species remaining at the start of step b), the thicker the film formed on the upper part of the pattern will be than the thickness of the film formed on the lower part of the pattern. On the other hand, the smaller the amount of the first reactive species remaining at the start of step b), the closer the thickness of the film formed on the upper part of the pattern will be to the thickness of the film formed on the lower part 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 according to the amount of the first reactive species remaining at the start of step b).

The substrate processing method according to the first embodiment may change the amount of the first reactive species remaining at the start of step b) by controlling the amount of the first reactive species introduced into the chamber in step a). The substrate processing method according to the first embodiment may change the amount of the first reactive species remaining at the start of step b) by controlling the dilution degree of the first reactive species introduced into the chamber in step a). Therefore, according to the first embodiment, the coverage of the film formed on the substrate can be easily controlled by adjusting the amount and dilution degree of the first reactive species.

In addition, in the substrate processing method according to the first embodiment, step a) may include a1) a step of introducing a first reactive species into the chamber, and a2) a step of purging at least a part of the first reactive species from the chamber. In addition, in the substrate processing method according to the first embodiment, the amount of the first reactive species purged in step a2) may be controlled to change the amount of the first reactive species remaining at the start of step b). Therefore, according to the first embodiment, the amount of the first reactive species in the chamber can be adjusted in the purging step. Therefore, according to the first embodiment, the coverage of the film formed on the substrate can be continuously controlled by simply adjusting the processing conditions. Also, according to the first embodiment, by changing the processing conditions of the purging step, an intermediate film formation mode between ALD and CVD can be easily realized.

In addition, in the substrate processing method according to the first embodiment, the amount of the first reactive species purged in step a2) may be 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 amount of the first reactive species remaining at the start of step b). Therefore, according to the first embodiment, the coverage of the film formed on the substrate can be controlled by selecting and adjusting an easily controllable condition from a plurality of processing conditions.

In addition, in the substrate processing method according to the first embodiment, step a) or step b) may be terminated before the reaction on the substrate surface becomes saturated. Therefore, the substrate processing method according to the first embodiment can use subconformal ALD to further finely adjust the coverage of the film formed on the substrate.

The substrate processing method according to the first embodiment may further include a step d) of etching the substrate using the film formed by step c) as a mask after the execution of step c). The substrate processing method according to the first embodiment may further include a step e) of repeatedly executing a process including steps c) and d) two or more times. Therefore, according to the first embodiment, the coverage can be continuously controlled to correct the shape of the mask before etching. Therefore, according to the first embodiment, the etching accuracy can be improved. According to the first embodiment, etching can be performed while correcting the shape of the mask.

In the substrate processing method according to the first embodiment, step c) may be performed in the same chamber. Therefore, according to the first embodiment, the processing throughput can be further improved. Furthermore, when the substrate processing method according to the first embodiment includes step d), step c) and step d) may be performed in the same chamber or in different chambers. Therefore, according to the first embodiment, the entire substrate processing can be optimized while balancing the film formation time and the etching time.

In the substrate processing method according to the first embodiment, step c) may be performed by setting the pressure in the chamber to about 10 to about 200 mTorr. Setting the pressure lower shortens the residence time, but the mixed mode according to the first embodiment can be achieved by adjusting other processing conditions. Therefore, according to the first embodiment, the increase in processing time can be suppressed and the throughput of substrate processing can be improved.

The substrate processing apparatus according to the first embodiment also includes a selection unit and an instruction unit. The selection unit selects a plurality of processes. The processes include, for example, steps a), b), and c). Step a) is a step of exposing a substrate having a pattern formed on its surface to a first reactive species in a chamber, thereby adsorbing the first reactive species to the surface of the substrate. Step b) is a step of exposing the substrate to a plasma formed from a second reactive species in a chamber, thereby forming a film on the surface of the substrate. Step c) is a step of repeating the process including steps a) and b) two or more times by changing the amount of the first reactive species remaining at the start of step b). In step c), the plurality of processes selected by the selection unit have different amounts of the first reactive species remaining at the start of step b). The instruction unit instructs the execution of the plurality of processes selected by the selection unit in the chamber. Therefore, according to the substrate processing apparatus according to the first embodiment, the coverage of the film formed on the substrate can be continuously controlled.

Second Embodiment
The substrate processing apparatus according to the first embodiment preliminarily sets processing conditions and selects a processing step according to a coverage to be achieved. Furthermore, the substrate processing apparatus according to the second embodiment selects and executes a processing step according to the state of a pattern on a substrate. The substrate processing method according to the second embodiment selects and executes a processing step according to, for example, the degree of roughness of a pattern on a substrate.

Figure 12 is a diagram showing an example of the configuration of the substrate processing apparatus 100A according to the second embodiment. The configuration of the substrate processing apparatus 100A according to the second embodiment is generally similar to that of the substrate processing apparatus 100 according to the first embodiment. However, the substrate processing apparatus 100A differs from the substrate processing apparatus 100 in that it has a corresponding memory unit 113 and an acquisition unit 123. The substrate processing apparatus 100A also differs from the substrate processing apparatus 100 in that it is communicatively connected to the measuring apparatus 300 via a network NW. Among the configurations of the substrate processing apparatus 100A, the description of the configurations in common with the substrate processing apparatus 100 will be omitted, and the different configurations will be described below.

The substrate processing apparatus 100A is communicatively connected to the processing apparatus 200 and the measuring apparatus 300 via the network NW. The network NW and the processing apparatus 200 are similar to the network NW and the processing apparatus 200 of the first embodiment (see FIG. 7).

The measuring device 300 measures the shape of the pattern formed on the substrate and outputs a value indicating the shape. The value output by the measuring device 300 is hereinafter also referred to as a measurement value. The type of measurement value output by the measuring device 300 is not particularly limited. The measurement value may be, for example, the aspect ratio of the pattern formed on the substrate. The measurement value may also be, for example, the standard deviation of a signal waveform representing the unevenness of the pattern formed on the substrate. The measurement value may also be, for example, the power spectral density (PSD) of a signal waveform representing the unevenness of the pattern formed on the substrate. Note that the standard deviation may be the same even when the periods of the unevenness are completely different, so it is preferable to use the power spectral density as the measurement value in order to improve measurement accuracy (see 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, the measurement value preferably includes at least the aspect ratio and the power spectral density.

For example, the measuring device 300 may be a device that derives the standard deviation of the shape of a pattern, power spectral density, etc., based on information and images obtained by analyzing a pattern formed on a substrate using a scanning electron microscope (SEM). In the example of FIG. 12, the substrate processing apparatus 100A and the measuring device 300 are connected via a network NW. However, the measuring device 300 may be configured to be disconnected from the substrate processing apparatus 100A, and a measurement value derived separately by an operator or the like may be input to the substrate processing apparatus 100A.

The substrate processing apparatus 100A includes a memory unit 110A, a control unit 120A, an input unit 130, an output unit 140, and a communication unit 150.

The storage unit 110A has a processing condition storage unit 111 and a processing storage unit 112 similar to those in the first embodiment, as well as a correspondence storage unit 113. The correspondence storage unit 113 stores the correspondence between the measurement values input from the measurement device 300 and the processing.

Figure 13 is a diagram showing an example of the configuration of information stored in the corresponding storage unit 113. In the example of Figure 13, the corresponding storage unit 113 stores "Device ID", "Measurement value, aspect ratio, PSD", and "Processing ID". "Device ID" is information that identifies a device to be formed by processing. "Device ID" may also be information that indicates target values of aspect ratio and PSD. "Measurement value, aspect ratio" indicates the aspect ratio of a pattern obtained by measuring the pattern formed on a substrate. "Measurement value, PSD" indicates the power spectral density of the pattern obtained by measuring the pattern formed on a substrate. "Processing ID" indicates the processing to be applied to the pattern of the corresponding "Measurement value" to achieve the corresponding "Device ID".

Figures 14A to 14D are diagrams for explaining the relationship between power spectrum density and pattern shape. Figure 14A is a diagram showing an example of low-frequency roughness of a pattern formed on a substrate. Figure 14B is a diagram showing an example of power spectrum density obtained by measuring a pattern formed on a substrate.

Here, low-frequency roughness refers to roughness, i.e., unevenness, that appears at a relatively large period compared to high-frequency roughness, and high-frequency roughness refers to roughness that appears at a relatively small period compared to low-frequency roughness.

Figure 14A (1) shows a state where a line and space pattern that should be formed in a straight line has an uneven shape, resulting in a wavy shape. Figure 14A shows the pattern viewed from above. In the example of Figure 14A (1), the spacing between the lines is different between X1 and X2. The power spectrum density obtained by measuring the pattern of Figure 14A (1) can be expressed as Figure 14B (1). The horizontal axis of the graph in Figure 14B indicates frequency (unit: nanometers [nm]), and the vertical axis indicates power spectrum density (unit: nm3), in other words, the amount of energy in each frequency band. In the graph of Figure 14B, the more to the right of the horizontal axis indicates the amount of roughness that occurs with a small cycle, i.e., high-frequency roughness, and the more to the left indicates the amount of roughness that occurs with a large cycle, i.e., low-frequency roughness.

Here, the roughness of the pattern in FIG. 14A (1) is improved to smooth out the irregularities (FIG. 14A (2)). In the example of FIG. 14A (2), the spacing between the lines is smoothed out, and the part that was X1 in (1) now has a spacing of X3, which is almost the same as the other parts. This also changes the shape of the power spectrum density graph. FIG. 14B (2) is an example of the power spectrum density obtained by measuring a pattern with improved roughness. FIG. 14B (2) shows that low-frequency roughness, that is, roughness that appears at a large period, has been improved and the pattern surface has been flattened.

Figure 14C shows an example of high-frequency roughness of a pattern formed on a substrate. Figure 14D shows another example of power spectrum density obtained by measuring a pattern formed on a substrate.

When the pattern with high frequency roughness shown in FIG. 14C (1) is represented using electron spectral density, it becomes as shown in FIG. 14D (1). At this time, the roughness of the pattern in FIG. 14C (1) is improved to smooth out the irregularities (FIG. 14C (2)). Then, the shape of the graph changes to FIG. 14D (2). In FIG. 14D (2), it can be seen that the high frequency roughness has been improved more than the low frequency roughness, and the pattern surface has been flattened.

The low-frequency roughness shown in FIG. 14B can be smoothed out, for example, by CVD. Films formed by CVD tend to deposit in the relatively large voids, thus filling in the relatively large recesses in the low-frequency roughness.

On the other hand, in the case of the high frequency roughness shown in FIG. 14D, the size of the recesses causing the roughness is relatively small when viewed from the perspective of the entire pattern. For this reason, the recesses cannot be preferentially filled by deposition using CVD. For this reason, it is preferable to use a mixed mode that combines ALD and CVD to improve high frequency roughness.

In the substrate processing method according to the second embodiment, before processing is performed, the shape of the pattern on the substrate to be processed, such as the roughness, is measured, and the processing conditions, i.e., the process to be adopted, are selected according to the measured value. This makes it possible to select a process according to the shape abnormality occurring in the pattern on the substrate, and to correct the pattern shape.

In the above, an example of selecting either CVD or the mixed mode depending on the roughness of the pattern on the substrate is shown, but the substrate processing method according to the second embodiment is not limited to this. For example, a first threshold and a second threshold greater than the first threshold are set in advance in accordance with the shape of the pattern on the substrate to be processed, such as the roughness. In one example, the first threshold is set to the upper limit value at which the roughness of the pattern on the substrate can be flattened by CVD, and the second threshold is set to the lower limit value at which the roughness of the pattern on the substrate can be flattened by ALD. Next, before the processing is performed or after a predetermined number of processings are performed, the shape of the pattern on the substrate to be processed, such as the roughness, is measured, and the measured value is compared with the first and second thresholds. If the measured value is equal to or less than the first threshold, CVD is selected as the film formation process. If the measured value is greater than the first threshold and less than the second threshold, the above-mentioned mixed mode is selected as the film formation process. If the measured value is equal to or greater than the second threshold, ALD is selected as the film formation process. The selected film formation process then improves the roughness of the pattern on the substrate.

Returning to FIG. 12, the description of the substrate processing apparatus 100A according to the second embodiment will continue. The control unit 120A has an acquisition unit 123 in addition to a selection unit 121 and an instruction unit 122 similar to those in the first embodiment.

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 power spectral density described above.

Figure 15 is a flow chart showing an example of the flow of the substrate processing method according to the second embodiment. First, the acquisition unit 123 acquires the measurement values of the pattern formed on the substrate to be processed (step S21). The acquisition unit 123 also acquires target values, such as a device ID, of the pattern to be formed on the substrate to be processed. Next, the selection unit 121 refers to the correspondence storage unit 113 and selects a process corresponding to the acquired target value and measurement value (step S22). The selection unit 121 sends the selected process to the instruction unit 122. The instruction unit 122 instructs the processing device 200 to execute a process based on the process received from the selection unit 121 and causes the processing device 200 to execute the process (step S23). This ends the process.

The substrate processing apparatus 100, 100A may repeatedly perform the above processes on one substrate. For example, the substrate processing apparatus 100, 100A may select and perform the next process each time a process is completed.

In the second embodiment, the correspondence table stored in the correspondence memory unit 113 may be updated as appropriate depending on the processing results in the processing apparatus 200. For example, the measuring apparatus 300 may acquire measurement values indicating the pattern shapes on the substrate before and after processing. For example, the measuring apparatus 300 may measure the state of the pattern on the substrate each time processing in the processing apparatus 200 is completed and transmit the measurement values to the substrate processing apparatus 100A. The substrate processing apparatus 100A may then update the correspondence table depending on the difference between the measurement values after processing and the target values. The substrate processing apparatus 100A may also generate the correspondence table by machine learning based on the measurement values of the pattern on the substrate before and after processing and the target values.

(Effects of the Second Embodiment)
As described above, the substrate processing method according to the second embodiment further includes a step of measuring a value indicating the shape of a pattern on the substrate surface before performing the processing, and a step of selecting processing conditions based on the measured value. The processing is performed under the selected processing conditions. For example, the substrate processing apparatus performs a purging step under the selected processing conditions. Therefore, according to the second embodiment, the substrate processing apparatus can select a processing to be performed according to the shape of the pattern on the substrate. Therefore, the substrate processing apparatus can select and perform a processing to achieve coverage according to the state of the pattern on the substrate.

The substrate processing method according to the second embodiment may also include a step of measuring a value indicating the shape of the pattern on the substrate surface after performing the process a predetermined number of times. The substrate processing method according to the second embodiment may also include a step of selecting processing conditions for the next process to be performed based on the difference between a value measured before performing the process and a value measured after performing the process a predetermined number of times. Therefore, according to the second embodiment, the processing performance can be evaluated before selecting the next process.

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

(An example of a processing device 200 according to an embodiment)
Fig. 16 is a diagram showing an example of the configuration of a processing apparatus 200 in which substrate processing in the first and second embodiments is performed. Fig. 16 shows a schematic cross section of the processing apparatus 200. The processing apparatus 200 shown in Fig. 16 is a parallel plate type plasma processing apparatus. However, the processing apparatus capable of performing the substrate processing in the first and second embodiments is not limited to the one shown in the figure.

The processing apparatus 200 includes a chamber 12 that is configured to be airtight. The chamber 12 has a substantially cylindrical shape, and defines a processing space S in which plasma is generated as its internal space. The processing apparatus 200 includes a mounting table 13 in the chamber 12. The upper surface of the mounting table 13 is formed as a mounting surface 54d on which a wafer W, which is an object to be processed, is placed. In this embodiment, the mounting table 13 includes a base 14 and an electrostatic chuck 50. The base 14 has a substantially circular plate shape and is provided below the processing space S. The base 14 is made of, for example, aluminum, and functions as a lower electrode.

The electrostatic chuck 50 is provided on the upper surface of the base 14. The electrostatic chuck 50 has a flat disk-shaped upper surface, which corresponds to a mounting surface 54d on which the wafer W is placed. The electrostatic chuck 50 has an electrode 54a and an insulator 54b. The electrode 54a is provided inside the insulator 54b, and a DC power supply 56 is connected to the electrode 54a via a switch SW. When a DC voltage is applied from the DC power supply 56 to the electrode 54a, a Coulomb force is generated, and the wafer W is attracted and held on the electrostatic chuck 50 by the Coulomb force. The electrostatic chuck 50 also has a heater 54c inside the insulator 54b. The heater 54c heats the electrostatic chuck 50 by supplying power from a power supply mechanism (not shown). This controls the temperatures of the mounting table 13 and the wafer W.

In this embodiment, the processing device 200 further includes a cylindrical holder 16 and a cylindrical support 17. The cylindrical holder 16 contacts the edges of the side and bottom surfaces of the base 14 to hold the base 14. The cylindrical support 17 extends vertically from the bottom of the chamber 12 and supports the base 14 via the cylindrical holder 16.

A focus ring 18 is provided on the upper surface of the peripheral portion of the base 14. The focus ring 18 is a member for improving the in-plane uniformity of the processing accuracy of the wafer W. The focus ring 18 is a plate-like member having a roughly ring shape, and is made of, for example, silicon, quartz, or silicon carbide.

In this embodiment, an exhaust path 20 is formed between the side wall of the chamber 12 and the cylindrical support 17. A baffle plate 22 is attached to the entrance of the exhaust path 20 or on its way. An exhaust port 24 is provided at the bottom of the exhaust path 20. The exhaust port 24 is defined by an exhaust pipe 28 fitted into 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 depressurized to a predetermined vacuum level. As a result, 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 that opens and closes the loading/unloading port for the wafer W is attached to the side wall of the chamber 12.

A high frequency power supply 32 is electrically connected to the base 14 via a matching device 34. The high frequency power supply 32 is a power supply for generating plasma, and applies high frequency power of a predetermined high frequency (e.g., 13 MHz) to the lower electrode, i.e., the base 14. A coolant flow path (not shown) is formed inside the base 14, and the processing device 200 cools the mounting table 13 by circulating a coolant through the coolant flow path. This controls the temperature of the mounting table 13 and the wafer W.

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

The electrode plate 40 is a conductive plate having a roughly circular plate shape, and constitutes an upper electrode. The electrode plate 40 is electrically connected to the high-frequency power supply 35 via a matching device 36. The high-frequency power supply 35 is a power supply for generating plasma, and applies high-frequency power of a predetermined high frequency (e.g., 60 MHz) to the electrode plate 40. When high-frequency power is applied to the base 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 base 14 and the electrode plate 40, i.e., the processing space S, and plasma is generated.

The electrode plate 40 is formed with a plurality of gas vent holes 40h. The electrode plate 40 is supported by the electrode support 42 so as to be detachable. A buffer chamber 42a is provided inside the electrode support 42. The processing apparatus 200 further includes a gas supply unit 44, and the gas supply unit 44 is connected to the gas inlet 25 of the buffer chamber 42a via a gas supply conduit 46. The gas supply unit 44 supplies a processing gas to the processing space S. This processing gas may be, for example, a processing gas for etching, or a processing gas for film formation. The electrode support 42 is formed with a plurality of holes each connected to the plurality of gas vent holes 40h, 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 gas vent holes 40h.

In this embodiment, a magnetic field forming mechanism 48 extending in an annular or concentric shape is provided on the ceiling of the chamber 12. This magnetic field forming mechanism 48 functions to facilitate the initiation of high-frequency discharge (plasma ignition) in the processing space S and to maintain the discharge in a stable manner.

In this embodiment, the processing apparatus 200 further includes a gas supply line 58 and a heat transfer gas supply unit 62. The heat transfer gas supply unit 62 is connected to the gas supply line 58. This gas supply line 58 extends to the upper surface of the electrostatic chuck 50 and extends in a ring shape on the upper surface. The heat transfer gas supply unit 62 supplies a heat transfer gas, such as He gas, between the upper surface of the electrostatic chuck 50 and the wafer W.

The operation of the processing apparatus 200 having the above configuration is generally controlled by a control unit 90. The control unit 90 is provided with a process controller 91 having a CPU (Central Processing Unit) and controlling each part of the processing apparatus 200, a user interface 92, and a storage unit 93. In this embodiment, the control unit 90 may be provided in the substrate processing apparatus 100, 100A.

The user interface 92 is composed of a keyboard through which the process manager inputs commands to manage the processing device 200, a display that visualizes and displays the operating status of the processing device 200, etc.

The storage unit 93 stores recipes that store control programs (software) and processing condition data for implementing various processes executed by the processing device 200 under the control of the process controller 91. Then, as necessary, an arbitrary recipe is called from the storage unit 93 by an instruction from the user interface 92, and executed by the process controller 91, so that the desired processing is performed by the processing device 200 under the control of the process controller 91. In addition, recipes such as control programs and processing condition data can be used in a state stored in a computer-readable computer storage medium (e.g., a hard disk, a CD, a flexible disk, a semiconductor memory, etc.). In addition, recipes such as control programs and processing condition data can be used online by transmitting them from other devices at any time, for example, via a dedicated line.

Figure 17 shows an example of a processing system that can be used to perform substrate processing in the first and second embodiments.

The processing system 1000 shown in FIG. 17 includes a control unit Cnt, a stage 1122a, a stage 1122b, a stage 1122c, a stage 1122d, a storage container 1124a, a storage container 1124b, a storage container 1124c, a storage container 1124d, a loader module LM, a load lock chamber LL1, a load lock chamber LL2, a transfer chamber 1121, and a plasma processing device 1010. The plasma processing device 1010 may be, for example, the processing device 200 shown in FIG. 16.

The control unit Cnt is a computer equipped with a processor, a storage unit, an input device, a display device, etc., and controls each unit of the processing system 1000, which will be described later. The control unit Cnt is connected to the transport robot Rb1, the transport robot Rb2, the optical observation device OC, the plasma processing device 1010, etc. The control unit Cnt may also serve as the control units 120, 120A of the substrate processing devices 100, 100A shown in Figures 7 and 12, and the control unit 90 of the processing device 200 shown in Figure 16. The control unit Cnt may also be the substrate processing device 100, 100A.

The control unit Cnt operates according to a computer program (a program based on an input recipe) for controlling each part of the processing system 1000, and sends out a control signal. The control signal from the control unit Cnt controls each part of the processing system 1000, for example, the transfer robots Rb1 and Rb2, the optical observation device OC, and each part of the plasma processing device 1010. In the plasma processing device 1010, the control signal from the control unit Cnt can control 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 sources 32 and 35, the power supply to the heater 54c, the coolant flow rate, and the coolant temperature. Each step of the substrate processing method according to the first and second embodiments can be executed by operating each part of the processing system 1000 under the control of the control unit Cnt. The storage unit of the control unit Cnt stores computer programs for executing the substrate processing methods according to the first and second embodiments, and various data used for execution, which can be read out.

The stages 1122a to 1122d are arranged along one edge of the loader module LM. Storage containers 1124a to 1124d are provided on the stages 1122a to 1122d, respectively. Wafers W can be stored in the storage containers 1124a to 1124d.

A transfer robot Rb1 is provided inside the loader module LM. The transfer robot Rb1 removes a wafer W stored in one of the storage containers 1124a to 1124d and transfers the wafer W to the load lock chamber LL1 or LL2.

The load lock chambers LL1 and LL2 are provided along another edge of the loader module LM and are connected to the loader module LM. The load lock chambers LL1 and LL2 constitute a preliminary decompression chamber. The load lock chambers LL1 and LL2 are each connected to the transfer chamber 1121.

The transfer chamber 1121 is a chamber that can be depressurized, and a transfer robot Rb2 is provided inside the transfer chamber 1121. The plasma processing device 1010 is connected to the transfer chamber 1121. The transfer robot Rb2 removes the wafer W from the load lock chamber LL1 or the load lock chamber LL2, and transfers the wafer W to the plasma processing device 1010.

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 by the transport robots Rb1 and Rb2. After the wafer W is accommodated in the optical observation device OC by the transport robot Rb1 and the wafer W is aligned in the optical observation device OC, the optical observation device OC measures the groove width of a pattern such as a mask on the wafer W and transmits the measurement result to the control unit Cnt. The optical observation device OC can measure the groove width of a pattern such as a mask formed in multiple regions on the surface of the wafer W. The measurement result by the optical observation device OC is used, for example, as the "measurement value" (see FIG. 15) in the second embodiment.

The embodiments disclosed herein should be considered in all respects as illustrative and not restrictive. The above-described embodiments may be omitted, substituted, or modified in various ways without departing from the scope and spirit of the appended claims.

100, 100A Substrate processing apparatus 110, 110A Memory section 111 Processing condition memory section 112 Processing memory section 113 Correspondence memory section 120, 120A Control section 121 Selection section 122 Instruction section 123 Acquisition section 130 Input section 140 Output section 150 Communication section 200 Processing apparatus 300 Measuring apparatus NW Network

Claims (20)

a) exposing a substrate having a pattern formed thereon to a first reactive species in a chamber such that the first reactive species is adsorbed onto the surface of the pattern ;
b) exposing the substrate to a plasma formed from a second reactive species in the chamber to form a film on a surface of the pattern ;
c) repeating the treatment including the steps a) and b) on the substrate two or more times by changing the residence amount of the first reactive species at the start of the step b);
A substrate processing method comprising: The substrate processing method according to claim 1, wherein in a), the amount of the first reactive species introduced into the chamber is controlled to change the amount of the first reactive species remaining at the start of b). The substrate processing method according to claim 1 or 2, wherein in step a), the amount of the first reactive species remaining at the start of step b) is changed by controlling the degree of dilution of the first reactive species introduced into the chamber. The a) is
a1) introducing the first reactant into the chamber;
a2) purging a portion of the first reactant from the chamber;
The method for processing a substrate according to claim 1 , further comprising: The substrate processing method according to claim 4, wherein the amount of the first reactive species remaining at the start of b) is changed by controlling the amount of the first reactive species purged in a2). a) exposing a substrate having a pattern formed thereon to a first reactive species in a chamber such that the first reactive species is adsorbed onto the surface of the substrate;
b) exposing the substrate to a plasma formed from a second reactive species in the chamber to form a film on a surface of the substrate;
c) repeating the process including the steps a) and b) two or more times by changing the residence amount of the first reactive species at the start of the step b);
Including,
The a) is
a1) introducing the first reactant into the chamber;
a2) purging at least a portion of the first reactant from the chamber;
Including,
In the step a2) , an amount of the first reactive species to be purged is controlled by changing at least one of a pressure in the chamber, a processing time, and a flow rate of a purge gas, thereby changing an amount of the first reactive species remaining at the start of the step b). The substrate processing method according to any one of claims 1 to 6, wherein a) or b) is terminated before the reaction on the surface of the substrate becomes saturated. a) exposing a substrate having a pattern formed thereon to a first reactive species in a chamber such that the first reactive species is adsorbed onto the surface of the substrate;
b) exposing the substrate to a plasma formed from a second reactive species in the chamber to form a film on a surface of the substrate;
c) repeating the process including the steps a) and b) two or more times by changing the residence amount of the first reactive species at the start of the step b);
Including,
A substrate processing method comprising : controlling a residence amount of the first reactive species at the start of step b) such that a thickness of a film formed on an upper portion of the pattern is greater than a thickness of a film formed on a lower portion of the pattern. a) exposing a substrate having a pattern formed thereon to a first reactive species in a chamber such that the first reactive species is adsorbed onto the surface of the substrate;
b) exposing the substrate to a plasma formed from a second reactive species in the chamber to form a film on a surface of the substrate;
c) repeating the process including the steps a) and b) two or more times by changing the residence amount of the first reactive species at the start of the step b);
Including,
A substrate processing method comprising controlling a residence amount of the first reactive species at the start of step b) so that a thickness of a film formed on an upper portion of the pattern is close to a thickness of a film formed on a lower portion of the pattern. d) The substrate processing method according to any one of claims 1 to 9, further comprising the step of etching the substrate using the film formed by c) as a mask. a) exposing a substrate having a pattern formed thereon to a first reactive species in a chamber such that the first reactive species is adsorbed onto the surface of the substrate;
b) exposing the substrate to a plasma formed from a second reactive species in the chamber to form a film on a surface of the substrate;
c) repeating the process including the steps a) and b) two or more times by changing the residence amount of the first reactive species at the start of the step b);
d) etching the substrate using the film formed by c) as a mask;
e) repeating the process including steps c) and d) two or more times ;
A method for processing a substrate, comprising : a) exposing a substrate having a pattern formed thereon to a first reactive species in a chamber such that the first reactive species is adsorbed onto the surface of the substrate;
b) exposing the substrate to a plasma formed from a second reactive species in the chamber to form a film on a surface of the substrate;
c) repeating the process including the steps a) and b) two or more times by changing the residence amount of the first reactive species at the start of the step b);
Including,
measuring a value indicating a shape of the pattern on the surface of the substrate before carrying out the step a);
selecting processing conditions based on the measured values;
Further comprising:
The substrate processing method, wherein the steps a), b), and c) are performed under the selected processing conditions. measuring a value indicating a shape of the pattern on the surface of the substrate after performing the process c) a predetermined number of times;
selecting processing conditions for a next process to be performed based on a difference between a value measured before performing step a) and a value measured after performing step c) a predetermined number of times;
The method of claim 12 further comprising: f) measuring a value indicative of the shape of the pattern on the surface of the substrate;
g) comparing said value with a first predetermined threshold and with a second threshold greater than said first threshold;
h) selecting a deposition process based on the results of the comparison; and
i) forming a film on a surface of the substrate by the selected deposition process;
The above h) is
If the value is equal to or less than the first threshold, a chemical vapor deposition (CVD) process is selected as the film formation process;
When the value is greater than the first threshold value and less than the second threshold value, the substrate processing method according to any one of claims 1 to 9 is selected as the film forming process;
When the value is equal to or greater than the second threshold, ALD (Atomic Layer Deposition) is selected as the film formation process. The substrate processing method according to any one of claims 1 to 10, wherein step c) is repeatedly performed until the shape of the pattern satisfies a predetermined condition. The substrate processing method according to any one of claims 1 to 11, wherein step c) is performed in the same chamber. The substrate processing method according to any one of claims 1 to 12, wherein step c) is performed by setting the pressure in the chamber to about 10 to about 200 mTorr. a) exposing a substrate having a pattern formed thereon to a first reactive species in a chamber such that the first reactive species is adsorbed onto the surface of the pattern ;
b) exposing the substrate to a plasma formed from a second reactive species in the chamber to form a film on a surface of the pattern ;
c) repeating the treatment including the steps a) and b) on the substrate two or more times by changing the residence amount of the first reactive species at the start of the step b);
a selection unit that selects a plurality of processes in which the retention amount of the first reactive species at the start of the process in the step c) is different from each other;
an instruction unit that instructs execution of the plurality of processes selected by the selection unit in the chamber;
The substrate processing apparatus includes: a chamber including a gas inlet and a gas outlet;
a plasma generating unit for generating plasma in the chamber;
A control unit;
Equipped with
The control unit is
a) exposing a substrate having a pattern formed thereon to a first reactive species in a chamber such that the first reactive species adsorbs on the surface of the substrate;
b) exposing the substrate to a plasma formed from a second reactive species in the chamber to form a film on the surface of the substrate;
Including,
controlling the coverage of the film by adjusting the residence time of the first reactant at the start of b);
A substrate processing apparatus configured to perform the process. a first chamber including a gas inlet and a gas outlet;
a first plasma generating unit that generates plasma in the first chamber;
a second chamber including a gas inlet and a gas outlet;
a second plasma generating unit that generates plasma in the second chamber;
a transfer chamber configured to be able to transfer a substrate between the first chamber and the second chamber;
A control unit;
Equipped with
The control unit is
a) placing a substrate having a pattern formed thereon in the first chamber;
b) exposing the substrate to a first reactive species in the first chamber such that the first reactive species adsorbs on the surface of the substrate;
c) exposing the substrate to a plasma formed from a second reactive species in the first chamber to form a film on the surface of the substrate;
d) after performing one or more cycles including b) and c), transferring the substrate from the first chamber and placing it in the second chamber;
e) etching the substrate in the second chamber using the film formed in c) as a mask;
Including,
controlling the coverage of the film by adjusting the residence time of the first reactant at the start of c);
A substrate processing system configured to perform the process.

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