KR20210058709A - Substrate processing method and substrate processing apparatus - Google Patents

Abstract

The present invention continuously controls the coverage of a film formed on a substrate. A substrate processing method according to the present invention includes a step of a) exposing a substrate having a pattern formed on the surface thereof to the first reactive species to adsorb the first reactive species to the surface of the substrate in a chamber. Further, the substrate processing method includes a step of b) forming a film on the surface of the substrate by exposing the substrate to plasma formed with the second reactive species in the chamber. In addition, the substrate processing method includes a step of c) repeating the processing including the steps a) and b) two or more times by changing the retention amount of the first reactive species at the start of the step b).

Description

A substrate processing method and a substrate processing apparatus TECHNICAL FIELD [SUBSTRATE PROCESSING METHOD AND SUBSTRATE PROCESSING APPARATUS}

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

Atomic Layer Deposition (ALD) is known as one of the techniques used in the manufacture of semiconductor devices. ALD is classified as one of Chemical Vapor Deposition (CVD). CVD is a method of forming a film on a substrate by placing a substrate in a chamber and then introducing a gas containing a component of a film to be formed into the chamber to cause a chemical reaction on the surface of the substrate or in a gas phase. Unlike CVD, ALD does not introduce a plurality of reactive gases into the chamber at once. First, a first reactive gas (precursor) is introduced into the chamber to be adsorbed onto the substrate, and the first reactive gas not adsorbed is discharged from the chamber. Subsequently, a second reactive gas is introduced into the chamber, and a film is formed by reacting with a component of the first reactive gas adsorbed on the substrate. Since ALD can control the film thickness at the atomic layer level using self-regulation, it is used for dense film formation.

[Patent Document 1] US Patent Application Publication No. 2005/70041 Specification

The present disclosure provides a technique capable of continuously controlling the coverage of a film formed on a substrate.

According to an aspect of the present disclosure, a substrate processing method realized by a substrate processing apparatus includes: a) exposing a substrate having a patterned surface thereon to a first reactive species in a chamber, so that the first reactive species is applied to the surface of the substrate. It includes an adsorption process. Further, the substrate processing method includes b) forming a film on the surface of the substrate by exposing the substrate to plasma formed of a second reactive species in the chamber. Further, the substrate treatment method includes a step of repeating the treatment including c) steps a) and b) two or more times by changing the amount of retention of the first reactive species at the start of step b).

According to the present disclosure, it is possible to continuously control the coverage of a film formed on a substrate.

1 is a flowchart showing an example of a flow of a substrate processing method according to a first embodiment.
2A is a flowchart showing a flow of Processing Example 1 executed by the substrate processing method according to the first embodiment.
2B is a flowchart showing the flow of Processing Example 2 executed by the substrate processing method according to the first embodiment.
2C is a flowchart showing the flow of Processing Example 3 executed by the substrate processing method according to the first embodiment.
2D is a flowchart showing the flow of Processing Example 4 executed by the substrate processing method according to the first embodiment.
3A is a diagram for explaining a relationship between a film forming method and coverage.
Fig. 3B is a schematic longitudinal sectional view of a pattern 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 a mixing mode in the first embodiment.
7 is a diagram showing an example of a configuration of a substrate processing apparatus according to the first embodiment.
8 is a diagram for explaining an example of processing conditions stored in the substrate processing apparatus according to the first embodiment.
9 is a diagram for explaining an example of processing 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 obtained by normalizing the experimental results shown in Fig. 10;
12 is a diagram illustrating an example of a configuration of a substrate processing apparatus according to a second embodiment.
13 is a diagram showing an example of a configuration of information stored in a corresponding storage unit.
14A is a diagram showing an example of low frequency roughness of a pattern formed on a substrate.
14B is a diagram showing an example of a power spectral density obtained by measuring a pattern formed on a substrate.
14C is a diagram showing an example of high frequency roughness of a pattern formed on a substrate.
14D is a diagram showing another example of power spectral density obtained by measuring a pattern formed on a substrate.
15 is a flowchart showing an example of the flow of the substrate processing method according to the second embodiment.
16 is a diagram showing an example of a configuration of a processing apparatus in which substrate processing in the first and second embodiments is performed.
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.

Hereinafter, embodiments disclosed will be described in detail based on the drawings. In addition, this embodiment is not restrictive. In addition, each embodiment can be appropriately combined within a range that does not contradict the contents of the process. In addition, in each drawing, the same reference|symbol is attached|subjected to the same or corresponding part.

In addition, in the following description, "top" refers to the ceiling direction of the processing apparatus, that is, the surface direction of the substrate disposed in the processing apparatus. In addition, "bottom" refers to the bottom direction of the processing apparatus, that is, the direction of the back surface of the substrate disposed in the processing apparatus. In addition, in order to indicate the pattern part formed on the substrate, when "upper" and "lower" are referred to, "upper" means the side of the surface of the substrate, that is, the side to be processed such as film formation or etching, and "lower" is the substrate. It means the back side, that is, the side which is not an object to be processed, such as film formation or etching. In addition, the thickness direction of the substrate is also referred to as a vertical direction, and a direction parallel to the substrate surface is also referred to as a horizontal direction.

In addition, in the following description, "reactive species" includes a gas containing a reactive species.

(First embodiment)

1 is a flowchart showing an example of a flow of a substrate processing method according to a first embodiment. The substrate processing method according to the first embodiment is executed by a substrate processing apparatus that controls a processing apparatus (eg, a chamber) in which processes such as etching, film formation, and cleaning are performed.

First, the substrate processing apparatus selects one or more processes that are successively executed on a substrate (eg, a semiconductor substrate made of silicon) (step S11). Subsequently, the substrate processing apparatus causes the processing apparatus to execute the selected process (step S12). When execution is complete, the process ends.

Here, the "process" includes one or more processes performed on the substrate. The one or more treatments are, for example, film formation treatment, etching treatment, cleaning treatment, temperature control treatment, and the like. Further, the "process" includes information on the execution order of one or more processes.

2A to 2D are flowcharts each showing a flow of processing examples 1 to 4 executed by the substrate processing method according to the first embodiment.

Process Example 1 shown in Fig. 2A is a film forming process by CVD. First, the substrate processing apparatus forms a film on the surface of the substrate by reacting the first reactive species and the second reactive species in the chamber (step SA1). Then, the substrate processing apparatus ends the processing.

Process example 2 shown in FIG. 2B is a film forming process by ALD (including "mix mode" to be described later). The treatment of treatment example 2 includes step a) and step b). In step a), the substrate processing apparatus exposes the substrate having a patterned surface thereon to the first reactive species in the chamber, and adsorbs the first reactive species to the surface of the substrate (step SB1). Subsequently, in step b), the substrate processing apparatus causes the substrate to be exposed to plasma formed of the second reactive species in the chamber to form 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 executed (step SB3). When it is determined that the predetermined number of cycles have not been executed (step SB3, No), the substrate processing apparatus returns to step SB1 and repeats the process. On the other hand, when it is determined that a predetermined number of cycles have been executed (step SB3, Yes), the substrate processing apparatus ends the processing.

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

Process 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 processing.

Process example 4 shown in FIG. 2D is a process in which a film forming process and etching under different conditions are combined. Process Example 4 is a process in which the processes of Process Example 1, Process Example 2, and Process Example 3 are sequentially executed. The substrate processing apparatus first performs processing example 1 (step SD1). Subsequently, the substrate processing apparatus executes Process Example 2 (step SD2). Subsequently, the substrate processing apparatus executes processing example 3 (step SD3). Then, the substrate processing apparatus ends the processing.

In addition, "process" includes processing condition information of each processing. The processing condition information includes, for example, the pressure inside the chamber, the frequency and power of a radio frequency applied to generate plasma, the type and flow rate of gas, the processing time, the temperature of each part of the chamber, and the like. Further, the "process" includes information on the number of times each process is executed and the number of times a plurality of processes are repeated in a predetermined order. For example, in the case of executing a plurality of cycles in the processing example 2 shown in Figs. 2A to 2D, different processing conditions can be set for each cycle. The "process" performed in the substrate processing method according to the first embodiment includes, for example, one or more processes for realizing film formation in different coverages for a pattern having a height difference formed on a substrate.

Here, "coverage" refers to a ratio of a film formed on the upper side of the pattern formed on the substrate and the film formed on the lower side of the pattern having an elevation difference. Coverage means, for example, a ratio of a film thickness of a film formed on an inner circumference of a hole formed in a substrate and a film thickness of a film formed below it. Also. For example, coverage refers to the ratio of the film thickness of a film formed on the surface of the substrate and the bottom surface of a 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 surface of the substrate regardless of the difference in height of the pattern. In this way, the coverage changes according to the method of the film forming process.

3A is a diagram for explaining a relationship between a film formation method and coverage. The horizontal axis of the graph of FIG. 3A represents a pattern formed on a substrate, for example, a vertical position within a hole (also referred to as an aspect ratio herein). In addition, the vertical axis represents the film thickness of the film formed on the pattern. For example, (1) denotes a position of a low aspect ratio, that is, a state in which the film thickness of a film formed on the upper portion of the pattern is large, and a position of a high aspect ratio, that is, a state in which no film is formed under the pattern. Further, (2) to (4) indicate a state in which the film thickness of the film gradually formed from the top to the bottom of the pattern decreases. Further, (5) represents a state in which the film thickness of the film formed from the top to the bottom of the pattern is substantially uniform.

Fig. 3B is a schematic longitudinal cross-sectional view of a pattern corresponding to (1) to (5) in Fig. 3(a). In (1) of FIG. 3B, the film F is formed only on the top of the pattern P. In (2) to (4) of FIG. 3B, the film formation amount is gradually changing from the top of the pattern P to the upper side of the side wall SW and the lower side of the side wall SW. (5) of FIG. 3B shows a state in which a film F having an approximately uniform thickness is formed anywhere on the top of the pattern P, the upper side of the side wall SW, the lower side of the side wall SW, and the bottom part BT. to be. (1) to (5) of Fig. 3B roughly correspond to (1) to (5) of Fig. 3(a).

Next, each method for realizing the coverage of FIGS. 3A and 3B (1) to (5) will be described.

4 is a diagram for explaining CVD. In CVD, a gas containing a component that reacts with each other to form a film is introduced into a chamber in which the substrate is disposed, and a film is formed on the substrate by reaction. In the example of Fig. 4, the gas A and the gas B are simultaneously introduced into the chamber in which the substrate Sub (Fig. 4A) is disposed. The reactive species in the introduced gas A and the reactive species in the gas B react to form a film on the substrate Sub (FIG. 4B). Since the components of the film reacted in the gas phase state are deposited from above, when there is a pattern having a height difference on the substrate, the coverage of the film formed by CVD decreases from the top to the bottom of the pattern.

5 is a diagram for explaining ALD. In ALD, a first reactive species and a second reactive species are sequentially introduced into a chamber in which the substrate is disposed to form a film. In the example of Fig. 5, the gas A (first reactive species) is first introduced into the chamber in which the substrate Sub (Fig. 5A) is disposed (Fig. 5B). Molecules in gas A are adsorbed on the surface of the substrate Sub (FIG. 5C). When the adsorption site disappears, the molecules do not deposit on the substrate Sub any more. The gas A remaining in the chamber is purged. Next, gas B (second reactive species) is introduced into the chamber (Fig. 5(D)). At this time, plasma may be generated from the 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 of the molecules of gas A on the substrate Sub react with the molecules of gas B, the molecules of the remaining gas B remain in the chamber as they are in the gas phase. And the remaining gas B is purged (Fig. 5(E)). In this way, in ALD, a film is formed by performing four steps of adsorption, purge, reaction (eg, oxidation), and purge. Since ALD realizes film formation in a self-controlled manner, the coverage of the film formed by ALD becomes a substantially constant film thickness from the top to the bottom of the pattern.

6 is a diagram for explaining a mixing mode in the first embodiment. The ``mix mode'' in the first embodiment means that the reaction of the first reactive species A and the second reactive species B in the gas phase state is generated similarly to CVD while using the flow of processing in the same manner as in ALD, so to speak. This is a film-forming method in which ALD and CVD are mixed.

In the example of Fig. 6, first, a gas A (first reactive species) is introduced into a chamber in which the substrate Sub (Fig. 6A) is disposed. Molecules in the introduced gas A are adsorbed onto the substrate Sub (FIG. 6B). In the mixed mode, after the molecules are adsorbed on the substrate Sub, gas A is not completely purged from the chamber (FIG. 6C). Then, the gas B (second reactive species) is introduced into the chamber as the gas A remains in the chamber (Fig. 6(D)). The molecules in the gas B react with the molecules of the gas A adsorbed on the substrate Sub and also react with the molecules of the gas A present in the gas phase in the chamber to form a film. For this reason, in addition to the self-controlling film formation of ALD, a film having coverage such as CVD is formed (Fig. 6(E)). In addition, gas A is, for example, a silicon-containing gas. In addition, gas B is, for example, an oxygen-containing gas. In addition, as the gas A, for example, a carbon-containing gas or the like can be used. Further, as the gas B, for example, a nitrogen-containing gas or the like can be used.

In the film formation in the mixed mode, coverage can be changed by adjusting the amount of the first reactive species remaining in the chamber (hereinafter, also referred to as the retention amount) when introducing the second reactive species into the chamber. The coverage in the mixed mode can be adjusted according to the following processing conditions.

(1) Treatment time of the purge step of the first reactive species (step (C) in Fig. 6)

(2) Pressure in the chamber in the purge process of the first reactive species

(3) Flow rate of purge gas used in the purge process of the first reactive species

(4) Degree of dilution of the first reactive species (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 equation (1).

T=(P×V)/(Q)...(1)

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 (Torr) in the processing space. V represents the volume (liter) of the processing space. Q represents the flow rate (sccm) of the gas. As can be seen from equation (1), the residence time T is proportional to the volume of the processing space and the pressure of the processing space, and is inversely proportional to the flow rate of the gas. Accordingly, the larger the volume of the processing space and the higher the pressure, the longer the residence time, and the higher the flow rate of gas, the shorter the residence time.

Therefore, when introducing the second reactive species into the chamber, the amount of the first reactive species remaining in the chamber can be increased by adjusting the processing 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 in the purge step of the first reactive species is increased.

(3) The flow rate of the purge gas used in the purge step of the first reactive species is decreased.

In addition, when the treatment conditions in the purge step of the first reactive species are not changed, the dilution degree of the first reactive species (the treatment condition (4)) is increased to reduce the amount of reactive molecules remaining without being adsorbed on the substrate. It is also possible to increase the retention amount of the first reactive species by increasing it. In addition, by not providing a purge step, it is also possible to maintain the amount of retention of the first reactive species.

As described above, in the substrate processing method according to the first embodiment, continuous coverage control is realized by combining film forming processes for realizing different coverage.

(Example of the configuration of the substrate processing device)

7 is a diagram showing an example of the configuration 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), for example. The substrate processing apparatus 100 is connected to the processing apparatus 200 through 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. Further, the network NW may be a wired network, a wireless network, or a combination thereof.

The processing apparatus 200 includes a processing space (chamber) in which processing is performed on the substrate, and performs processing of the substrate. Details of the processing device 200 will be described later. However, the configuration and type of the processing device 200 are not particularly limited. The processing apparatus 200 may be, for example, a plasma processing apparatus using an arbitrary plasma source such as a capacitively coupled plasma (CCP), an inductively coupled plasma (ICP), or a microwave plasma. The processing apparatus 200 performs a film forming process such as Atomic Layer Deposition (ALD) and Chemical Vapor Deposition (CVD), an etching process, and the like. The processing apparatus 200 may be a device that uses plasma or does not use plasma for processing a substrate.

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.

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 random access memory (RAM), a read only memory (ROM), a hard disk, an optical memory device, and the like.

The controller 120 controls operations 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 central processing unit (CPU), a micro processing unit (MPU), and the like.

The input unit 130 receives input of information 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 peripheral circuits thereof.

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

(Information stored in the memory 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 processing conditions for processing of a substrate performed by the processing apparatus 200, such as film formation and etching.

8 is a diagram for describing an example of processing conditions stored in the substrate processing apparatus 100 according to the first embodiment. The processing conditions are, for example, processing conditions for each film forming process described with reference to FIGS. 4 to 6. The processing conditions include, for example, CVD, the pressure inside the chamber, the frequency and power of a high frequency (HP) applied during plasma generation, the type of gas introduced into the chamber, the flow rate (ratio) of the gas, 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 the mixed mode, the treatment conditions are the adsorption process of the first reactive species (process a1), the purge process of the first reactive species (process a2), the reaction process of the second reactive species (process b1), and the second You may set about each of the purge steps (step b2) of the reactive species. (Step a1), (Step a2), (Step b1) and (Step b2) are shown in Fig. 2B.

In the example of FIG. 8, the processing conditions include "condition ID (Identifier)", "step number", "pressure", "high frequency (HP)", "gas", "flow rate", "treatment time" and "temperature". Includes. The "condition ID" is an identifier that uniquely identifies each processing condition. The "step number" is a number for identifying each process when one process includes a plurality of processes. "Pressure" is the pressure value in the chamber in the said process. "High frequency (HP)" is a high frequency frequency and power applied to an electrode in the chamber in the above processing. "Gas" is information specifying the gas to be introduced into the chamber in the above processing. "Flow rate" is the flow rate of the corresponding gas. "Treatment time" represents the time of the above treatment. "Temperature" is the temperature of a predetermined portion of the chamber that is set when performing the above processing.

For example, step numbers "1" to "4" are stored as processing conditions identified by "condition ID: P100" in FIG. 8. This indicates that the processing conditions specified by the condition ID "P100" include four steps. In addition, in correspondence with "step number, 1", "pressure, XXmT", "gas, X/Y", "flow rate, R1/R2", "treatment time, 2 sec", "temperature, T1/T2/T3 」Is remembered. This indicates that in the process condition of the condition ID "P100", in the step specified by the step number "1", the pressure in the chamber is set to XXmT. In addition, in the above process, it refers to supplying X gas (here, it means an unspecified gas) and Y gas into the chamber at a flow rate ratio of R1 sccm to R2 sccm. In addition, it indicates that the treatment time of the above process is 2 seconds. In addition, during the execution of the above process, the temperature of the predetermined portion of the chamber is set to T1 degrees Celsius, T2 degrees Celsius, and T3 degrees Celsius.

In addition, the processing conditions indicated by condition ID "P100" in Fig. 8 correspond to ALD. Among the processing conditions of the condition ID "P100", the step number "1" is the processing condition of the adsorption step (step a1), and the step number "2" is the processing condition of the purge step (step a2) after the adsorption step. In addition, step number "3" is a processing condition of a reaction process (process b1), and step number "4" is a processing condition of a purge process (process b2) after a reaction process. In addition, the processing conditions indicated by condition ID "P200" in Fig. 8 correspond to CVD (refer to Fig. 2A, step SA1). Since the processing of the condition ID "P200" is one step, only the processing conditions of the step number "1" are stored. In addition, in Fig. 8, the processing conditions indicated by condition IDs "P301" to "P303" correspond to the mixed mode. The processing conditions of the condition IDs "P301" to "P303" are almost the same as the processing conditions of the condition ID "P100", but the "processing time" of the step number "2" is different. This is because the processing conditions of the condition IDs "P301" to "P303" shorten the processing time of the purge step (step a2) in order to realize the mixing mode.

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

9 is a diagram for describing an example of a process stored in the substrate processing apparatus 100 according to the first embodiment. In the example of Fig. 9, the process includes "process ID", "number of cycles", and "condition ID/sequence". The "process ID" is an identifier that uniquely identifies the process. The "number of cycles" is the number of times the processing is executed based on the corresponding processing condition in the processing. The "condition ID/procedure" is a processing condition of the processing to be executed in the processing and a sequence of executing the processing when a plurality of processing is executed. In addition, the "condition ID/order" may not be a condition ID and a sequence, but may be information about a process ID and a sequence.

For example, in the example of Fig. 9, "number of cycles, 1" and "condition ID/order, P200" are stored in correspondence with "process ID, S001". This indicates that in the process specified by the process ID "S001", the process based on the process condition specified by the condition ID "P200" is executed once. The processing conditions specified by the condition ID "P200" are stored in the processing condition storage unit 111. That is, the processing conditions of condition ID "P200" are chamber pressure "XXmT", high frequency (HP) "Z1MHz/Z2W", gas "X/Y", flow rate, and "R1/R2". In addition, it is a processing time "10 sec" and a temperature "T1/T2/T3".

In addition, in the example of FIG. 9, for example, "the number of cycles, 5" and "condition ID/order, S001⇒S003⇒S100" are stored in correspondence with the process ID "S500". This indicates that the processing specified by the processing ID "S500" is to execute the processing specified by each of the processing IDs "S001", "S003", and "S100" in this order. In addition, it shows that the three processes are sequentially repeated 5 times. The process specified by the process ID "S001" is CVD, and the process specified by the process ID "S003" is in the mixed mode (see Fig. 8). When the process specified by the process ID "S100" is etching, the process ID "S500" means that CVD, ALD, and etching are continued and repeatedly executed five times.

(Configuration and function of the control unit 120)

Returning to Fig. 7, the configuration and function of the control unit 120 will be described. The control unit 120 includes a selection unit 121 and an instruction unit 122.

The selection unit 121 receives an instruction input through the input unit 130 or the communication unit 150. Then, the selection unit 121 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 processing to the instruction unit 122.

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

(Experimental example)

10 is a diagram showing experimental results of processing based on the substrate processing method according to the first embodiment. Fig. 10A shows the coverage obtained when CVD is performed once for 10 seconds based on the process ID "S001" (refer to Figs. 8 and 9). Fig. 10B shows the coverage obtained when 40 times a process in which the purge time is set to 0.5 seconds in the mixed mode is executed based on the process ID "S002" (refer to Figs. 8 and 9). Fig. 10C shows the coverage obtained when a process in which the purge time is set to 0.7 seconds in the mixed mode is executed 70 times based on the process ID "S003" (refer to Figs. 8 and 9). Fig. 10D shows coverage obtained when a process in which the purge time is set to 1 second in the mixed mode is executed 105 times based on the process ID "S004" (refer to Figs. 8 and 9). Fig. 10E shows the coverage obtained when the ALD is executed 200 times based on the process ID "S005" (refer to Figs. 8 and 9).

In addition, the difference between the processing conditions of the condition IDs "P301", "P302", "P303", and "P100" is only the length of the purge time of the first reactive species. In (B) of FIG. 10, the purge time is 0.5 seconds, (C) is 0.7 seconds, (D) is 1 second, (E) is 10 seconds, and the purge time is gradually increased from (B) to (E). . For this reason, when the second reactive species (oxygen-containing gas in the example of FIG. 10) is introduced into the chamber, the retention amount of the first reactive species (X-containing gas in the example of FIG. 10) goes from (B) to (E). Is decreasing. For this reason, in (B), the film-forming amount in the CVD mode is the largest, and it is considered that the film-forming amount in the CVD mode is decreasing from (C) to (D). In addition, in (E), it is considered that film formation is performed in the ALD mode.

In the example of Fig. 10A, a film is formed substantially above the pattern, and almost no film is formed below it. That is, under the processing conditions of Fig. 10A, coverage equivalent to Fig. 3B(1) is realized.

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 under the pattern. That is, under the processing conditions of Fig. 10B, coverage substantially corresponding to Fig. 3B(2) is realized.

In the example of Fig. 10C, the film thickness of the film to be formed is generally higher than that of (B), while the film thickness decreases from top to bottom like in (B). That is, it can be said that (C) of FIG. 10 is approximately the coverage corresponding to (3) of FIG. 3B.

In the example of Fig. 10D, the film thickness of the formed film is further increased than that of (C), and the film formation is also recognized at the bottom of the pattern. It can be said that (D) of FIG. 10 is approximately the coverage corresponding to (4) of FIG. 3B.

In the example of Fig. 10E, there is almost no difference in the thickness of the formed film between the upper and lower portions of the pattern, and substantially uniform film formation is realized. That is, under the processing conditions of Fig. 10E, coverage equivalent to Fig. 3B(5) is realized.

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

11 is a graph obtained by normalizing the experimental results shown in FIG. 10. As can be seen from Fig. 11, the coverage gradually changes between (A) to (E), and an intermediate film formation mode between CVD and ALD is realized. In this way, according to the substrate processing method according to the first embodiment, it is possible to continuously change the coverage to realize a film formation of a desired coverage.

In addition, 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 upper portion of the pattern, and a film may be formed only on the upper portion of the pattern. Further, by ending the treatment before the second reactive paper spreads to the bottom of the pattern, a film may be formed only on the pattern upper portion. By using the sub-conformal ALD, the coverage can be controlled more flexibly.

(Effect of the first embodiment)

As described above, the substrate processing method according to the first embodiment includes a step a), a step b), and a step c). Step a) is a step in which a substrate having a pattern formed thereon is exposed to the first reactive species in the chamber, and the first reactive species is adsorbed onto the surface of the substrate. Step b) is a step of forming a film on the surface of the substrate by exposing the substrate to plasma formed of the second reactive species in the chamber. Step c) is a step in which the treatment including step a) and step b) is repeated two or more times by changing the retention amount of the first reactive species at the start of step b). For this reason, 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, as the amount of retention of the first reactive species at the beginning of step b) increases, the thickness of the film formed on the pattern becomes thicker than the thickness of the film formed on the lower part of the pattern. On the other hand, as the amount of retention of the first reactive species at the start of step b) decreases, the thickness of the film formed on the upper part of the pattern and the thickness of the film formed under the pattern become closer. For this reason, according to the substrate processing method according to the first embodiment, the coverage of the film formed on the substrate can be continuously controlled according to the amount of retention of the first reactive species at the start of the step b).

In addition, in the substrate processing method according to the first embodiment, in step a), by controlling the amount of the first reactive species introduced into the chamber, the retention amount of the first reactive species at the start of the step b) is changed. You can do it. In addition, in the substrate processing method according to the first embodiment, in step a), by controlling the dilution degree of the first reactive species introduced into the chamber, the retention amount of the first reactive species at the start of the step b) is reduced. You can change it. For this reason, according to the first embodiment, the coverage of the film formed on the substrate can be easily controlled by adjusting the amount of the first reactive species or the degree of dilution.

In addition, in the substrate processing method according to the first embodiment, the step a) includes 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. Also good. Further, in the substrate processing method according to the first embodiment, the amount of retention of the first reactive species at the start of the step b) may be changed by controlling the amount of the first reactive species purged in the step a2). For this reason, according to the first embodiment, it is possible to further adjust the amount of the first reactive species in the chamber in the step of purging. For this reason, according to the first embodiment, the coverage of the film formed on the substrate can be continuously controlled by simple adjustment of the processing conditions. Further, according to the first embodiment, by changing the processing conditions of the purge step. An intermediate film formation mode between ALD and CVD can be easily realized.

Further, in the substrate processing method according to the first embodiment, the amount of the first reactive species purged in the step 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, and the step b You may change the retention amount of the first reactive species at the start of ). For this reason, according to the first embodiment, the coverage of the film formed on the substrate can be controlled by selecting and adjusting conditions that are easy to control 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 surface of the substrate is saturated. For this reason, in the substrate processing method according to the first embodiment, the coverage of the film formed on the substrate can be further finely adjusted by using subconformal ALD.

In addition, the substrate processing method according to the first embodiment may further include a step of etching the substrate by using the film formed by the step c) as a mask (protective film) after the execution of d) step c). In addition, in the substrate processing method according to the first embodiment, step c) may be repeatedly performed until the shape of the pattern satisfies a predetermined condition. Further, e) a step of repeating the treatment including step c) and step d) two or more times may be included. For this reason, according to the first embodiment, it is possible to perform etching after correcting the shape of the mask by continuously controlling the coverage. For this reason, according to the first embodiment, the etching accuracy can be improved. Further, according to the first embodiment, etching can be performed while correcting the shape of the mask.

In addition, in the substrate processing method according to the first embodiment, step c) may be performed in the same chamber. For this reason, according to the first embodiment, the throughput of the processing can be further improved. In addition, when the substrate processing method according to the first embodiment includes the step d), the steps c) and d) may be performed in the same chamber or may be performed in different chambers. For this reason, according to the first embodiment, it is possible to optimize the entire substrate processing while balancing the film formation time and the etching time.

Further, 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. If the pressure is set low, the residence time is shortened, but the mixing mode according to the first embodiment can be realized by adjusting other processing conditions. For this reason, according to the first embodiment, an increase in processing time can be suppressed and the throughput of the substrate processing can be improved.

Further, the substrate processing apparatus according to the first embodiment includes a selection unit and an instruction unit. The selection unit selects a plurality of processes. The treatment includes, for example, step a), step b) and step c). Step a) is a step in which a substrate having a pattern formed thereon is exposed to the first reactive species in the chamber, and the first reactive species is adsorbed onto the surface of the substrate. Step b) is a step of forming a film on the surface of the substrate by exposing the substrate to plasma formed of the second reactive species in the chamber. Step c) is a step in which the treatment including step a) and step b) is repeated two or more times by changing the retention amount of the first reactive species at the start of step b). In step c), the plurality of treatments selected by the selection unit differ from each other in the amount of retention of the first reactive species at the start of step b). The instruction unit instructs the execution of a plurality of processes selected by the selection unit in the chamber. For this reason, according to the substrate processing apparatus according to the first embodiment, the coverage of the film formed on the substrate can be continuously controlled.

(2nd embodiment)

In the substrate processing apparatus according to the first embodiment, processing conditions are set in advance, and processing of the processing is selected according to the desired coverage. Further, in the substrate processing apparatus according to the second embodiment, processing is selected and executed according to the state of the pattern on the substrate. The substrate processing method according to the second embodiment selects and executes the processing according to the degree of roughness of the pattern on the substrate, for example.

12 is a diagram showing an example of a configuration of a substrate processing apparatus 100A according to the second embodiment. The configuration of the substrate processing apparatus 100A according to the second embodiment is substantially the same as 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 storage unit 113 and an acquisition unit 123. Further, the substrate processing apparatus 100A is different from the substrate processing apparatus 100 in that it is connected to communicate with the measurement apparatus 300 via a network NW. Among the configurations of the substrate processing apparatus 100A, descriptions of the configurations common to those of the substrate processing apparatus 100 are omitted, and different configurations will be described below.

The substrate processing apparatus 100A is communicatively connected with the processing apparatus 200 and the measuring apparatus 300 via a network NW. The network NW and the processing device 200 are the same as the network NW and the processing device 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 measurement device 300 is also referred to as a measurement value hereinafter. The type of measurement value output by the measurement device 300 is not particularly limited. The measured value may be, for example, the aspect ratio of the pattern formed on the substrate. Further, the measured value may be, for example, a standard deviation of a signal waveform indicating irregularities of a pattern formed on a substrate. Further, the measured value may be, for example, a power spectral density (PSD) of a signal waveform indicating irregularities of a pattern formed on a substrate. In addition, since the standard deviation may be the same even when the periods of the irregularities are completely different, it is preferable to use the power spectral density as a measurement value to improve the measurement accuracy (Chris A. Mack, “Reducing roughness in extreme ultra violet lithography. ”In Journal of Micro/Nanolithography, MEMS, and MOEMS, 17(4), 041006(2018)). In the second embodiment, it is preferable that the measured value includes at least the aspect ratio and the power spectral density.

For example, the measurement device 300 derives the standard deviation of the pattern shape, the power spectral density, etc., based on information obtained by analyzing a pattern formed on a substrate with a scanning electron microscope (SEM) and an image. It may be a device. In addition, in the example of FIG. 12, it is assumed that the substrate processing apparatus 100A and the measurement apparatus 300 are connected by a network NW. However, the measurement device 300 may be unconnected with the substrate processing device 100A, and a measurement value derived separately by an operator or the like may be input to the substrate processing device 100A.

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

The storage unit 110A includes a corresponding storage unit 113 in addition to the processing condition storage unit 111 and the processing storage unit 112 as in the first embodiment. The correspondence storage unit 113 stores the correspondence between the measurement value input from the measurement device 300 and the process.

13 is a diagram showing an example of the configuration of information stored in the corresponding storage unit 113. In the example of Fig. 13, the correspondence storage unit 113 stores "device ID", "measurement value, aspect ratio, PSD", and "process ID". The "device ID" is information specifying a device to be formed by processing. Further, the "device ID" may be information indicating an aspect ratio and a target value of the PSD. "Measurement value, aspect ratio" represents the aspect ratio of the pattern obtained by measuring the pattern formed on the substrate. "Measurement value, PSD" represents the power spectral density of the pattern obtained by measuring the pattern formed on the substrate. "Process ID" represents a process applied to a pattern of a corresponding "measurement value" in order to achieve a corresponding "device ID".

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

Here, the low-frequency roughness refers to roughness that appears in a relatively large period compared to the high-frequency roughness, that is, the roughness, and the high-frequency roughness refers to the roughness that appears in a relatively small period compared to the low-frequency roughness.

Fig. 14A(1) shows a state in which irregularities are formed in the pattern of the line and space to be formed in a straight line and thus have a wavy shape. 14A is a state viewed from top to bottom of the pattern. In the example of (1) in Fig. 14A, the line-to-line spacing is different in X1 and X2. The power spectral density obtained by measuring the pattern of (1) of FIG. 14A can be expressed as (1) of FIG. 14B. The horizontal axis of the graph of Fig. 14B represents the frequency (unit·nanometer [nm]), and the vertical axis indicates the power spectral density (unit·nm ³ ), that is, the magnitude of energy in each frequency band. In the graph of FIG. 14B, the right side of the horizontal axis indicates a larger amount of roughness occurring in a small period, that is, a high frequency roughness, and the left side indicates a large amount of roughness occurring in a larger period, that is, a large amount of low-frequency roughness.

Here, the roughness of the pattern in (1) of FIG. 14A is improved to make the irregularities flat (2) of FIG. 14A). In the example of (2) of Fig. 14A, the distance between the line and the line becomes uniform, so that the portion X1 in (1) is substantially the same distance X3 as the other portions. Then, the shape of the graph of the power spectral density is also changed. 14B (2) is an example of the power spectral density obtained by measuring a pattern with improved roughness. In Fig. 14B(2), it is shown that the low-frequency roughness, that is, the roughness that appears in a large period, is improved and the pattern surface is flattened.

14C is a diagram showing an example of high frequency roughness of a pattern formed on a substrate. 14D is a diagram showing another example of the power spectral density obtained by measuring a pattern formed on a substrate.

When the pattern having the high frequency roughness shown in Fig. 14C (1) is shown using the electron spectral density, it is as shown in Fig. 14D (1). At this time, the roughness of the pattern of Fig. 14C (1) is improved to make the irregularities flat (Fig. 14C (2)). Then, the shape of the graph changes as shown in (2) of FIG. 14D. In Fig. 14D(2), it can be seen that the high-frequency roughness is improved compared to the low-frequency roughness, and the pattern surface is flattened.

The low frequency roughness shown in Fig. 14B can be flattened by, for example, CVD. Since the film formed by CVD has a tendency to deposit in a relatively large void portion, the low-frequency roughness fills in a relatively large recess.

On the other hand, in the high-frequency roughness shown in Fig. 14D, the size of the concave portion causing the roughness as a whole is relatively small when viewed as a whole. For this reason, in the film formation by CVD, the recess cannot be filled with priority. For this reason, it is preferable to use a mixed mode in which ALD and CVD are combined to improve the high frequency roughness.

In the substrate processing method according to the second embodiment, a shape such as roughness of a pattern on a substrate to be processed is measured before performing the processing, and a processing condition to be adopted, that is, a processing, is selected in accordance with the measured value. For this reason, processing can be selected according to the shape abnormality occurring in the pattern on the substrate, and the pattern shape can be corrected.

Although the example in which either CVD or mixed mode is selected according to the roughness of the pattern on the substrate has been shown above, the substrate processing method according to 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 set in advance corresponding to the shape of the pattern on the substrate to be processed, such as roughness. In one example, the first threshold is set to an upper limit at which the roughness of the pattern on the substrate can be flattened by CVD, and the second threshold is set to a lower limit at which the roughness of the pattern on the substrate can be flattened by ALD. Then, before the processing is executed or after a predetermined number of processing is performed, the shape, such as roughness, of the pattern on the substrate to be processed is measured, and the measured value is compared with the first threshold value and the second threshold value. When the measured value is less than or equal to the first threshold, CVD is selected as the film forming process. In addition, when the measured value is greater than the first threshold and less than the second threshold, the mixing mode described above is selected as the film forming process. In addition, when the measured value is equal to or greater than the second threshold, ALD is selected as the film forming process. Then, the roughness of the pattern on the substrate is improved by the selected film forming process.

Returning to Fig. 12, the description of the substrate processing apparatus 100A according to the second embodiment is continued. The control unit 120A includes an acquisition unit 123 in addition to the selection unit 121 and the instruction unit 122 as in the first embodiment.

The acquisition unit 123 acquires a measurement value from the measurement device 300 or the like through the input unit 130 and/or the communication unit 150. The measurement values acquired by the acquisition unit 123 include the above-described aspect ratio and power spectral density.

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

Further, the substrate processing apparatuses 100 and 100A may repeatedly perform the above processing for one substrate. For example, the substrate processing apparatuses 100 and 100A may select and execute the next processing each time the execution of the processing is completed.

In addition, in the second embodiment, the correspondence table stored in the correspondence storage unit 113 may be appropriately updated according to the result of processing in the processing device 200. For example, in the measuring apparatus 300, a measurement value indicating the shape of a pattern on a substrate before and after processing may be obtained. For example, the measurement device 300 may measure the state of the pattern on the substrate each time processing in the processing device 200 is finished and transmit it to the substrate processing device 100A. Further, the substrate processing apparatus 100A may update the correspondence table according to the difference between the measured value and the target value after processing. Further, the substrate processing apparatus 100A may generate a correspondence table by machine learning based on the measured values and target values of the patterns on the substrate before and after processing execution.

(Effect of the second embodiment)

As described above, the substrate treatment method according to the second embodiment further includes a step of measuring a value representing a pattern shape of the substrate surface before performing the treatment, and a step of selecting a treatment condition based on the measured value. do. Further, the processing is executed under the selected processing conditions. For example, the substrate processing apparatus performs a purge process under selected processing conditions. For this reason, according to the second embodiment, the substrate processing apparatus can select the processing to be performed according to the pattern shape on the substrate. For this reason, the substrate processing apparatus can select and execute a process for realizing coverage according to the state of the pattern on the substrate.

Further, the substrate treatment method according to the second embodiment may include a step of measuring a value representing a pattern shape on the substrate surface after performing the treatment a predetermined number of times. In addition, the substrate processing method according to the second embodiment is a step of selecting a processing condition for a subsequent processing based on a difference between a value measured before performing the processing and a value measured after performing the processing a predetermined number of times. You may include. For this reason, according to the second embodiment, after evaluating the processing performance, the next processing can be selected.

In addition, the substrate processing method of the second embodiment may further 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 repeatedly performed two or more times. In this case, film formation and etching may be performed in the same chamber or in different chambers.

(Example of processing device 200 according to one embodiment)

16 is a diagram showing an example of a configuration of a processing apparatus 200 in which substrate processing in the first and second embodiments is performed. 16 shows a schematic cross-section of the processing apparatus 200. In addition, 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 illustrated one.

The processing apparatus 200 has a chamber 12 configured to be airtight. The chamber 12 has a substantially cylindrical shape, and as its internal space, a processing space S in which plasma is generated is defined. 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 as a processing target is placed. In this embodiment, the mounting table 13 has a base 14 and an electrostatic chuck 50. The base 14 has a substantially disk shape and is provided below the processing space S. The base 14 is made of aluminum, for example, and has a function 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 top surface, and the top surface corresponds to an arrangement surface 54d on which the wafer W is disposed. 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 through 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. Further, the electrostatic chuck 50 has a heater 54c inside the insulator 54b. The heater 54c heats the electrostatic chuck 50 by supplying electric power from a power supply mechanism (not shown). Accordingly, the temperature of the mounting table 13 and the wafer W is controlled.

In the present embodiment, the processing apparatus 200 further includes a cylindrical holding portion 16 and a cylindrical supporting portion 17. The cylindrical holding part 16 holds the base 14 by contacting the edge of the side surface and the bottom surface of the base 14. The cylindrical support portion 17 extends in the vertical direction from the bottom portion of the chamber 12 and supports the base 14 through the cylindrical holding portion 16.

A focus ring 18 is provided on the upper surface of the edge portion of the base 14. The focus ring 18 is a member for improving the in-plane uniformity of the processing precision of the wafer W. The focus ring 18 is a plate-shaped member having a substantially annular 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 inlet or in the middle of the exhaust passage 20. In addition, an exhaust port 24 is formed at the bottom of the exhaust path 20. The exhaust port 24 is defined by an exhaust pipe 28 fitted 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 reduced to a predetermined degree of vacuum. Accordingly, 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 is attached to the side wall of the chamber 12 to open and close the carrying-in/out port of the wafer W.

A high frequency power supply 32 is electrically connected to the base 14 through a matching device 34. The high frequency power supply 32 is a power source for generating plasma, and applies high frequency power of a predetermined high frequency (eg, 13 MHz) to the lower electrode, that is, the base 14. Further, a refrigerant flow path (not shown) is formed inside the base 14, and the processing apparatus 200 cools the mounting table 13 by circulating the refrigerant through the refrigerant flow path. Accordingly, the temperature of the mounting table 13 and the wafer W is controlled.

The processing apparatus 200 also has 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 substantially disk shape, and constitutes an upper electrode. A high frequency power supply 35 is electrically connected to the electrode plate 40 through a matching device 36. The high frequency power supply 35 is a power source for generating plasma, and applies high frequency power of a predetermined high frequency (for example, 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, the space between the base 14 and the electrode plate 40, that is, a processing space ( A high-frequency electric field is formed in S) to generate plasma.

A plurality of gas vent holes 40h are formed in the electrode plate 40. The electrode plate 40 is supported detachably by the electrode support 42. A buffer chamber 42a is provided inside the electrode support 42. The processing apparatus 200 further includes a gas supply unit 44, and a gas supply unit 44 is connected to the gas inlet 25 of the buffer chamber 42a through 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. In the electrode support 42, a plurality of holes are formed in each of the plurality of gas vent holes 40h, and the plurality of holes communicate with 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 hole 40h.

In this embodiment, a magnetic field forming mechanism 48 extending annularly or concentrically is provided in the ceiling portion of the chamber 12. This magnetic field forming mechanism 48 facilitates the initiation of high-frequency discharge (plasma ignition) in the processing space S and functions to stably maintain the discharge.

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 a gas supply line 58. This gas supply line 58 extends to the upper surface of the electrostatic chuck 50 and extends annularly on the upper surface. The heat transfer gas supply unit 62 supplies 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 device 200 having the above configuration is controlled by the control unit 90 as a whole. The control unit 90 is provided with a process controller 91, a user interface 92, and a storage unit 93, which are equipped with a CPU (Central Processing Unit) to control each unit of the processing apparatus 200. In this embodiment, the control unit 90 may be provided in the substrate processing apparatuses 100 and 100A.

The user interface 92 includes a keyboard for inputting a command in order for the process manager to manage the processing device 200, and a display for visualizing and displaying the operation status of the processing device 200.

In the storage unit 93, a control program (software) for realizing various processes executed in the processing apparatus 200 by control of the process controller 91, a recipe storing processing condition data, and the like are stored. And, if necessary, by calling an arbitrary recipe from the storage unit 93 by an instruction from the user interface 92 or the like, and executing it in the process controller 91, in the processing device 200 under the control of the process controller 91 The desired treatment is done. In addition, a recipe such as a control program or processing condition data may be stored in a computer storage medium (for example, a hard disk, a CD, a flexible disk, a semiconductor memory, etc.) that can be read by a computer. In addition, recipes such as control programs and processing condition data can be transmitted from other devices at any time through, for example, a dedicated line, and used online.

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 processing system 1000 shown in FIG. 17 includes a control unit (Cnt), a cradle 1122a, a cradle 1122b, a cradle 1122c, a cradle 1122d, a receiving container 1124a, a receiving container 1124b, and a receiving 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 apparatus 1010 are provided. The plasma processing apparatus 1010 may be, for example, the processing apparatus 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, and the like, and controls each unit of the processing system 1000 to be described later. The control unit Cnt is connected to a transfer robot Rb1, a transfer robot Rb2, an optical observation device OC, a plasma processing device 1010, and the like. The control unit Cnt may also serve as the control units 120 and 120A of the substrate processing apparatuses 100 and 100A shown in FIGS. 7 and 12 and the control unit 90 of the processing apparatus 200 shown in FIG. 16. Further, the control unit Cnt may be the substrate processing apparatuses 100 and 100A.

The control unit Cnt operates according to a computer program (a program based on an input recipe) for controlling each unit of the processing system 1000 and transmits a control signal. Each unit of the processing system 1000, for example, the transfer robots Rb1 and Rb2, the optical observation device OC, and each unit of the plasma processing device 1010 are controlled by a control signal from the control unit Cnt. In the plasma processing device 1010, the selection and flow rate of the gas from the gas supply unit 44, the exhaust of the exhaust device 26, and the power from the high-frequency power sources 32, 35, according to a control signal from the control unit Cnt. The supply, power supply to the heater 54c, the refrigerant flow rate, and the refrigerant temperature can be controlled. In addition, each step of the substrate processing method according to the first and second embodiments may be performed by operating each unit of the processing system 1000 under control by the control unit Cnt. In the storage unit of the control unit Cnt, a computer program for executing the substrate processing method according to the first and second embodiments and various data used for execution are stored freely to be read.

The cradles 1122a to 1122d are arranged along one edge of the loader module LM. On each of the cradles 1122a to 1122d, storage containers 1124a to 1124d are provided, respectively. Wafers W may be accommodated in the storage containers 1124a to 1124d.

A transfer robot Rb1 is installed in the loader module LM. The transfer robot Rb1 pulls out the wafer W accommodated in either 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 the other 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 connected to the transfer chamber 1121, respectively.

The transfer chamber 1121 is a chamber capable of depressurizing, and a transfer robot Rb2 is installed in the transfer chamber 1121. A plasma processing apparatus 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 apparatus 1010.

The processing system 1000 is provided with 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 transfer robot Rb1 and the transfer robot Rb2. After the wafer W is accommodated in the optical observing device OC by the transfer robot Rb1, and the wafer W is aligned in the optical observing device OC, the optical observing device OC is The groove width of a pattern such as a mask of (W) is measured, and the measurement result is transmitted to the control unit Cnt. In the optical observation device OC, the groove width of a pattern such as a mask formed in a plurality of regions on the surface of the wafer W can be measured. The measurement result by the optical observation apparatus OC is used, for example as a "measurement value" (refer FIG. 15) in 2nd Embodiment.

It should be considered that the embodiment disclosed this time is an illustration in all points and is not restrictive. The above-described embodiments may be omitted, substituted, or changed in various forms without departing from the scope of the appended claims and the spirit thereof.

100, 100A: substrate processing apparatus 110, 110A: storage unit
111: processing condition storage unit 112: processing storage unit
113: correspondence storage unit 120, 120A: control unit
121: selection unit 122: instruction unit
123: acquisition unit 130: input unit
140: output unit 150: communication unit
200: processing device 300: measuring device
NW: network

Claims (18)

a) in a chamber, exposing a substrate having a pattern on its surface to a first reactive species, and adsorbing the first reactive species to the surface of the substrate; and
b) forming a film on the surface of the substrate by exposing the substrate to plasma formed of a second reactive species in the chamber,
c) a step in which the treatment comprising a) and b) is repeated two or more times by changing the retention amount of the first reactive species at the start of b).
Substrate processing method comprising a. The substrate processing according to claim 1, wherein the amount of retention of the first reactive species at the start of b) is changed by controlling the amount of the first reactive species introduced into the chamber in a). Way. The retention amount of the first reactive species at the start of b) according to claim 1 or 2, wherein by controlling the dilution degree of the first reactive species introduced into the chamber in a). Substrate processing method that is to change. The method according to any one of claims 1 to 3, wherein a) is,
a1) introducing the first reactive species into the chamber,
a2) a process of purging at least a part of the first reactive species from the chamber
Substrate processing method comprising a. The substrate processing method according to claim 4, wherein the retention amount of the first reactive species at the start of b) is changed by controlling the amount of the first reactive species purged in a2). The method of claim 5, wherein the amount of the first reactive species to be purged in a2) is changed by changing at least one of a pressure in the chamber, a purge time, and a flow rate of a purge gas, and at the start of b) The substrate processing method according to claim 1, wherein the retention amount of the first reactive species is changed. 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 is saturated. The first reactive species at the start of b) according to any one of claims 1 to 6, wherein the thickness of the film formed on the upper part of the pattern becomes thicker than the thickness of the film formed under the pattern. The substrate processing method to control the amount of retention of. The first reactive species at the start of b) according to any one of claims 1 to 6, wherein the thickness of the film formed on the upper part of the pattern becomes close to the thickness of the film formed under the pattern. The substrate processing method to control the amount of retention of. The substrate processing method according to any one of claims 1 to 9, further comprising: d) etching the substrate using the film formed by c) as a mask. The substrate processing method according to claim 10, further comprising: e) repeating the treatment including c) and d) two or more times. The process according to any one of claims 1 to 11, wherein before performing the a), a value representing the shape of the pattern on the surface of the substrate is measured, and
Process of selecting treatment conditions based on measured values
And further comprising, wherein a), b) and c) are performed under the selected processing conditions. The method of claim 12, wherein after performing the c) a predetermined number of times, measuring a value representing the shape of the pattern on the surface of the substrate;
A step of selecting processing conditions for subsequent processing based on the difference between the value measured before executing a) and the value measured after executing c) a predetermined number of times.
Substrate processing method comprising a further. The substrate processing method according to any one of claims 1 to 10, wherein c) is repeatedly executed until the shape of the pattern satisfies a predetermined condition. The substrate processing method according to any one of claims 1 to 11, wherein c) is performed in the same chamber. The method according to any one of claims 1 to 12, wherein c) is performed by setting the pressure in the chamber from about 10 mTorr to about 200 mTorr. As a substrate processing method,
A step of measuring a value representing the shape of the pattern on the surface of the substrate,
A step of comparing the value with a predetermined first threshold and a second threshold greater than the first threshold; and
A step of selecting a film forming treatment based on the comparison result, and
Forming a film on the surface of the substrate by the selected film formation treatment,
The process of selecting the film forming process,
When the value is less than or equal to 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, a mix mode is selected as the film forming process,
When the value is greater than or equal to the second threshold, ALD (Atomic Layer Deposition) is selected as the film forming process,
The mix mode is
a) in a chamber, exposing a substrate having a pattern on its surface to a first reactive species, and adsorbing the first reactive species to the surface of the substrate; and
b) forming a film on the surface of the substrate by exposing the substrate to plasma formed of a second reactive species in the chamber,
c) a step in which the treatment comprising a) and b) is repeated two or more times by changing the retention amount of the first reactive species at the start of b).
Substrate processing method comprising a. As a substrate processing apparatus,
A chamber including a gas inlet and a gas outlet;
A plasma generator configured to generate plasma in the chamber; And
A controller configured to control the entire process of the device to process the substrate, the controller
a) in the chamber, the substrate having a pattern formed thereon is exposed to a first reactive species, so that the first reactive species is adsorbed to the surface of the substrate,
b) in the chamber, the substrate is exposed to the plasma generated by the plasma generator and formed as a second reactive species to form a film on the surface of the substrate,
c) the treatment comprising a) and b) is repeated two or more times by changing the retention amount of the first reactive species at the start of b).
The substrate processing apparatus being programmed.

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