JP6066847B2 - Substrate processing method and control apparatus - Google Patents

Description

  The present invention relates to a substrate processing method and a control apparatus.

  In the manufacture of a semiconductor device, a desired device is manufactured by repeatedly performing various processes such as a film forming process and an etching process on a semiconductor wafer (hereinafter referred to as a wafer) as an object to be processed.

  For example, in a film forming process on a wafer, a holder in which a large number of wafers are held in a shelf shape is disposed in a vertical heat treatment apparatus (hereinafter referred to as a vertical substrate processing apparatus), and CVD (Chemical Vapor A film is formed on the wafer by Deposition treatment, oxidation treatment, or the like.

  Conventionally, (dry) etching of a film formed on a wafer has been performed in a single-wafer type using, for example, a parallel plate type plasma processing apparatus. However, in recent years, from the viewpoint of improving throughput and the like, a process for performing both a film forming process and an etching process in a vertical substrate processing apparatus has been proposed. Specifically, a first film formation process, an etching process, and then a second film formation process are performed on a wafer on which a pattern such as a trench or a hole is formed in a vertical substrate processing apparatus. There has been proposed a DED (Deposition Etch Deposition) process in which a film forming material is embedded in the recesses (see, for example, Patent Document 1).

  By performing the film formation process and the etching process in the vertical substrate processing apparatus, it is considered that a large number of wafers can be simultaneously subjected to the film formation process and then the etching process, so that the throughput is improved.

JP 2012-209394 A

  In recent years, with the demand for higher speed of semiconductor devices, finer wiring patterns, and higher integration, the width and diameter of trenches are several tens of nm or less. In the case where a film forming material is formed in such a narrow trench or hole pattern, an overhang tends to occur because the opening of the pattern is blocked with the film forming material. When the next film formation process is performed in a state where the overhang occurs and the pattern opening width is narrow, the film formation material cannot be sufficiently embedded in the interior, resulting in problems such as voids. . In order to embed a film forming material on a wafer without voids using a DED process in a vertical substrate processing apparatus, it is important to control the film forming amount and the etching amount in the film forming process and the etching process.

  In order to solve the above problems, a substrate processing method for embedding a film forming material without voids in a DED process in a vertical substrate processing apparatus is provided.

A processing container capable of arranging a substrate holder for holding a plurality of substrates in multiple stages at a predetermined interval; a heater for heating the inside of the processing container;
A processing gas introduction part for introducing a film forming gas and an etching gas into the processing container;
An exhaust section for exhausting the inside of the processing container;
A first film forming process on a substrate on which a predetermined concavo-convex pattern is formed in advance, using a vertical substrate processing apparatus having a control device and a control device for controlling the operation of the vertical substrate processing apparatus. A substrate processing method for embedding a film-forming substance in a recess of the concavo-convex pattern by an etching process and a second film-forming process,
The substrate processing method includes:
A first film-forming condition including a first film-forming time of the first film-forming process, so that the film-forming substance is buried without voids in the recess after the second film-forming process; The control device distributes the optimal time distribution for the first etching condition including the first etching time of the etching process and the second film forming condition including the second film forming time of the second film forming process. Calculating step,
A process step of performing the first film forming process, the first etching process, and the second film forming process on the substrate based on the calculated optimal time distribution ;
A substrate processing method.

  In the DED process in the vertical substrate processing apparatus, it is possible to provide a substrate processing method in which a film forming material is embedded without voids.

It is a schematic block diagram of an example of the vertical substrate processing apparatus which concerns on this embodiment. It is a schematic block diagram of an example of the control apparatus which concerns on this embodiment. It is the schematic for demonstrating an example of the DED process which concerns on this embodiment. It is a flowchart of an example of the substrate processing method which concerns on this embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

(Vertical substrate processing equipment)
First, the vertical substrate processing apparatus according to this embodiment will be described. The vertical heat treatment apparatus of the present embodiment can arrange a holder in which a large number of semiconductor wafers as an example of an object to be processed are held in a shelf shape, and can simultaneously perform a film forming process and an etching process on a large number of semiconductor wafers. Substrate processing apparatus.

  FIG. 1 shows a schematic configuration diagram of an example of a vertical substrate processing apparatus according to the present embodiment.

  The vertical substrate processing apparatus 100 according to the present embodiment includes a processing container 102 made of, for example, quartz whose longitudinal direction is vertical. The processing container 102 has a double tube structure of, for example, a cylindrical inner cylinder 102a and a ceiling-mounted outer cylinder 102b concentrically disposed outside the inner cylinder 102a.

  The lower end portion of the reaction tube 102 is hermetically held by a manifold 104 formed of stainless steel or the like. The manifold 104 may be configured to be fixed to a base plate (not shown).

The manifold 104 has a processing gas containing one or more film forming gases for film forming processing, a processing gas containing one or more etching gases for etching processing, or an inert gas (for example, N ₂ gas). ) And the like. Although FIG. 1 shows a configuration in which one gas introduction unit is installed, the present invention is not limited in this respect. For example, it is preferable to dispose the gas introduction units 106 at three locations, an upper portion, a middle portion, and a lower portion, in the height direction of the wafer boat 126 described later. By providing a plurality of gas introducing portions 106, the uniformity between the surfaces of the semiconductor wafer W (hereinafter referred to as the wafer W) can be improved in the film forming process and the etching process. In other words, one or a plurality of gas introduction units 106 can be provided according to the number of wafers W, the type of processing gas used, desired process conditions, and the like.

The type of processing gas is not particularly limited. For example, when polysilicon (polysilicon) as a gate electrode is embedded in a wafer W in which trenches and holes are formed in advance using a chemical vapor deposition (CVD) method, nitrogen (N ₂ ) gas or hydrogen (H ₂ ) Thermal decomposition of monosilane (SiH ₄ ) gas or the like in a gas atmosphere. Further, when a silicon oxide film as an insulating film is embedded in the wafer W in which trenches and holes are formed in advance, it is deposited using SiH ₄ gas and oxygen (O ₂ ) gas. That is, a processing gas can be selected as appropriate according to a desired process. Also, the type of etching gas can be appropriately selected according to the type of film to be formed.

  A pipe 110 for introducing the various gases described above into the processing container 102 is connected to the gas introduction unit 106. The pipe 110 is provided with a flow rate adjusting unit such as a mass flow controller (not shown), a valve (not shown), and the like for adjusting each gas flow rate.

  The manifold 105 also has a gas exhaust unit 108 that exhausts the inside of the processing container 102. The gas exhaust unit 108 is connected to a vacuum pump 112 capable of reducing the pressure in the processing vessel 102 and a pipe 116 serving as a vacuum exhaust path having an opening degree variable valve 114 and the like.

  A furnace port 118 is formed at the lower end of the manifold 105, and a disk-shaped lid 120 made of, for example, stainless steel is provided in the furnace port 118. The lid 120 is provided so as to be movable up and down by the lifting mechanism 122, and the furnace port 118 can be sealed.

  On the lid 120, for example, a heat insulating cylinder 124 made of quartz is installed. Further, on the heat insulating cylinder 124, for example, a wafer boat 126 made of quartz, for example, which holds about 25 to 150 wafers W in multiple stages at a predetermined interval in a horizontal state is mounted.

  The wafer boat 126 is carried into the processing container 102 by raising the lid 120 using the elevating mechanism 122, and the wafer W held in the wafer boat 126 is subjected to various processes. In addition, after various processes are performed, the lid 120 is lowered using the elevating mechanism 122 to be carried out from the inside of the processing container 102 to the lower loading area.

  Further, on the outer peripheral side of the processing container 102, for example, a cylindrical heater 128 capable of controlling the heating of the processing container 102 to a predetermined temperature is provided.

  The heater 128 is preferably divided into a plurality of zones. In the example shown in FIG. 1, heaters 128 a to 128 e are provided from the upper side to the lower side in the vertical direction. The heaters 128a to 128e are configured such that the heat generation amounts can be independently controlled by the power controllers 130a to 130e, respectively. In addition, temperature sensors (not shown) are installed on the inner wall of the inner cylinder 102a and / or the outer wall of the outer cylinder 102b, corresponding to the heaters 128a to 128e. Note that the number of divisions of the heater 128 is not limited to the example illustrated in FIG. 1, and may be divided into, for example, three zones from the upper side to the lower side in the vertical direction.

  The plurality of wafers W placed on the wafer boat 126 constitute one batch, and a film forming process and an etching process are simultaneously performed. At this time, it is preferable that at least one of the wafers W placed on the wafer boat 126 is a monitor wafer. The monitor wafer is preferably arranged corresponding to each of the divided heaters 128a to 128e, but may not be arranged corresponding to each. For example, ten monitor wafers may be arranged in five zones, or three monitor wafers may be arranged.

  Further, the vertical substrate processing apparatus 100 according to the present embodiment has a control device 132 inside or outside thereof. When the control device 132 is provided outside, the control device 132 can control the vertical substrate processing apparatus 100 by communication means such as wired or wireless.

  FIG. 2 shows a schematic configuration diagram of an example of the control device 132 according to the present embodiment.

  As shown in FIG. 2, the control device 132 includes a model storage unit 134, a recipe storage unit 136, a ROM (Read-Only Memory) 138, a RAM (Random Access Memory) 140, an I / O port 142, A central processing unit (CPU) 144 and a bus 146 that connects these components to each other are configured.

  The model storage unit 134 stores at least a process model described later. The model storage unit 134 preferably stores a thermal model described later.

  The recipe storage unit 136 stores a process recipe that determines control means in accordance with the type of etching process or film forming process executed by the vertical substrate processing apparatus 100. The process recipe is a recipe prepared for each process that is actually performed by the user. For example, the pressure change from the loading of the wafer W to the vertical substrate processing apparatus 100 to the unloading of the processed wafer W, It defines processing conditions such as temperature change, start and stop timing of gas supply such as process gas, and supply amount of process gas. And a recipe is updated based on the process conditions determined based on the process model mentioned later.

  The ROM 138 is a storage medium that includes an EEPROM (Electrically Erasable Programmable Read-Only Memory), a flash memory, a hard disk, and the like, and stores an operation program of the CPU 144 and the like.

  The RAM 140 functions as a work area for the CPU 144.

  The I / O port 142 supplies measurement signals related to processing conditions such as temperature, pressure, processing gas flow rate, and the like to the CPU 144, and outputs control signals output from the CPU 144 to various parts (a controller (not shown) of the opening variable valve 114, power The controller 130, a mass flow controller (not shown) connected to the gas introduction unit 106, a temperature sensor (not shown) arranged on the inner wall of the inner cylinder 102a, and the like. In addition, an operation panel 148 that allows a user to operate the vertical substrate processing apparatus 100 is connected to the I / O port 142.

  The CPU 144 executes the operation program stored in the ROM 138 and controls the operation of the vertical substrate processing apparatus 100 according to the process recipe stored in the recipe storage unit 136 in accordance with an instruction from the operation panel 148.

  The bus 146 transmits information between the units.

(Substrate processing method)
[Outline of substrate processing method]
Next, a substrate processing method by the DED process using the above-described vertical substrate processing apparatus 100 will be described with reference to the drawings.

  FIG. 3 is a schematic diagram for explaining an example of the DED process according to the present embodiment. In FIG. 3, the process of embedding the film-forming substance 204 in the pattern 200 by repeatedly performing the film-forming process and the etching process on the wafer W having the base film 202 on which the pattern 200 such as a trench or a hole is formed will be described. To do. In the example of FIG. 3, the process of embedding the film-forming substance 204 in the pattern 200 by sequentially performing the film-forming process, the etching process, and the film-forming process will be described. It may be a process of embedding the film-forming substance 204 by performing processing.

  First, as shown in FIG. 3A, a plurality of wafers W having a base film 202 on which a pattern 200 such as a trench or a hole is formed are placed in a vertical substrate processing apparatus 100 via a wafer boat 126. Carry in.

  Then, as shown in FIG. 3B, predetermined film forming conditions including at least a film forming time (for example, a film forming time t1 in the film forming process from FIG. 3A to FIG. 3B). Thus, a film forming material 204 is formed on at least the pattern 200. Thereby, as shown in FIG. 3B, the film thickness of the film forming material 204a corresponding to the “upper part” near the opening in the depth direction of the pattern 200 corresponds to H1, and corresponds to the “lower part” near the bottom. The film thickness of the film forming material 204c to be formed is H3, and the film thickness of the film forming material 204b corresponding to the position between the “upper” and “lower” is H2.

  In recent years, it has been required to form a film-forming material in a high aspect ratio hole or trench. In this case, due to the film forming process described above, the diameter at the opening is smaller than the diameter at the bottom of the pattern 200, and overhang is likely to occur. When an overhang occurs and the next film formation process is performed in a state where the opening width of the trench or hole is narrow, the film formation material cannot be sufficiently embedded in the inside and a void (cavity) is generated. Occurs.

  Therefore, in consideration of the film forming conditions including at least the film forming time in the first film forming process and the film forming conditions including at least the film forming time in the second film forming process described later, the etching including at least the etching time. Under the conditions, the film-forming substance 204 is etched (see FIG. 3C). For example, in the etching process from FIG. 3B to FIG. 3C, the film formation material 204 is etched under the etching conditions including the film formation time t2. Accordingly, the film thickness of the film forming material 204a corresponding to the “upper portion” near the opening is H1 ′, and the film thickness of the film forming material 204c corresponding to the “lower” near the bottom portion is H3 ′. And the film thickness of the film forming material 204b corresponding to the position between the “lower part” is H2 ′.

  Then, as shown in FIG. 3D, under the film forming conditions including the film forming time (the film forming time t3 in the film forming process from FIG. 3C to FIG. 3D), the film forming material By depositing 204 again, the deposition material 204 is embedded in the pattern 200.

  Here, a wide range of research has been conducted on film formation using a vertical substrate processing apparatus. Therefore, the relationship between the film formation conditions and the film formation amount according to the type of the base film 202, the type of the film forming material 204, the diameter of the pattern 200, the aspect ratio, and the like is already known. However, strict adjustment of the etching amount (or etching rate) using the vertical substrate processing apparatus is not performed. In the film forming process and the etching process using the vertical substrate processing apparatus 100, the present inventors minimize the human effort and time by simultaneously adjusting the film forming amount and the etching amount using the control device 132. However, it has been found that the film-forming substance 204 can be easily embedded in the recesses of the pattern 200 without voids with a short TAT (Turn Around Time). More specifically, the control device 132 distributes the optimal time distribution regarding the film formation time t1 in the first film formation process, the etching time t2 in the etching process, and the film formation time t3 in the second film formation process. calculate. Based on this time distribution, the control device 132 controls the vertical substrate processing apparatus 100 to process the substrate. As a result, it has been found that the film-forming substance 204 can be easily embedded in the recesses of the pattern 200 without voids with a short TAT.

FIG. 4 shows an example of a flowchart of the substrate processing method according to the present embodiment. The substrate processing method according to this embodiment is as follows:
A substrate processing method for embedding a film forming substance in a concave portion of a pattern by a first film forming process, a first etching process, and a second film forming process on a substrate on which a predetermined uneven pattern is formed in advance, The substrate processing method is
The first film-forming conditions including the first film-forming time of the first film-forming process and the first of the first etching process so that the film-forming substance is buried in the recess without voids after the second film-forming process. A calculation step (S300) in which the control device calculates the first etching condition including the etching time and the second film forming condition including the second film forming time of the second film forming process;
Based on the calculated first film formation condition, first etching condition, and second film formation condition, the first film formation process, the first etching process, and the second film formation process are performed on the substrate. Carrying out a processing step (S310);
Have

  As described above, the control device 132 itself may be a single device, or may be incorporated in the vertical substrate processing apparatus 100 as a control unit of the vertical substrate processing apparatus 100. .

  As a control target, for example, from the viewpoint of adjusting the film formation amount and the etching amount between the surfaces of the plurality of wafers W, for example, each of the heaters 128a to 128e among the multiple wafers W placed on the wafer boat 126. A total of five wafers W can be selected one by one from the location corresponding to the zone. Further, from the viewpoint of adjusting the film formation amount and the etching amount in the surface of the wafer W, for example, two locations of the central portion and the peripheral portion of the wafer W can be selected as control targets. Furthermore, from the viewpoint of adjusting the film formation amount and the etching amount in the depth direction of the pattern 200 of the wafer W, in the depth direction of the pattern 200, an “upper part” near the opening, and a “lower part” near the bottom, It is possible to select three locations, “center” at an arbitrary position between the upper and lower portions, as control targets. However, the present invention is not limited in this respect.

  Note that, as described above, in the example of FIG. 3, the process of embedding the film forming material 204 by performing the film forming process, the subsequent etching process, and the film forming process has been described. However, the present invention is not limited in this respect. For example, a process of embedding the film forming material 204 by repeating the film forming process and the subsequent etching process a plurality of times and then performing the film forming process again may be used. In this case, the control apparatus 132 controls the film forming conditions including the film forming time in each film forming process and the etching conditions including the etching time in each etching process. That is, the control device 132 adjusts the film formation amount and the etching amount at the same time, and easily embeds the film formation material without voids in a short TAT (Turn Around Time) while minimizing human labor and time. Can do.

[Effects of film formation time and etching time on film formation amount and etching amount]
Next, the reason why the film forming material 204 can be embedded in the recesses of the pattern 200 without voids by optimizing the film forming time and the etching time in the substrate processing method of this embodiment will be described. First, the relationship between the film formation time and the film formation amount and the relationship between the etching time and the etching amount will be described.

  For example, in the film forming material 204 of FIG. 3B or the like, the film forming material 204a corresponding to the “upper part” in the depth direction of the pattern 200, the film forming material 204b corresponding to the “middle part”, and the “lower part”. Strictly speaking, the film formation rate and the etching rate of the film formation material 204c depend on the film thickness distribution shape of the film formation material 204 that has already been formed. However, in general, the film formation speed (film formation amount) of the “upper part” is greatly influenced by the film formation time compared with the film formation speed (film formation amount) of the “middle part” and the “lower part”. . In general, in the short term, the etching rate (etching amount) of the “upper part” has a greater influence on the etching time than the etching rate (etching amount) of the “middle part” and “lower part”. receive. Therefore, by selecting a condition such that the etching rate of the “upper part” is higher than the etching rate of the “middle part” and the “lower part”, a film forming material is formed so that voids are not generated at least in the recesses of the pattern 200. 204 can be embedded. At this time, the relationship between the film forming time of the film forming process and the etching time of the etching process and the film forming amount and the etching amount in each of the upper part, the middle part, and the lower part is modeled in advance. Based on this model, the relationship between the processing conditions including the combination of the first film formation time, the etching time, and the second film formation time and the film thickness of the film formation material 204 is modeled. Then, based on the model created in advance, for each desired process content, the control device 132 calculates an optimal time distribution regarding the film formation time and the etching time.

[Influence of other parameters on film formation and etching]
In the substrate processing method of the present embodiment, the control device 132 may be configured to calculate optimum processing conditions for processing conditions other than time (film formation time and etching time).

  The processing conditions other than the time include, for example, a film forming temperature, a flow rate of a film forming gas, and a pressure at the time of film forming (that is, a pressure in the processing container 102) in the film forming process. The temperature, the flow rate of the etching gas, and the pressure during etching (that is, the pressure in the processing container 102) are included. That is, the control device 132 may be configured to calculate optimum conditions for the processing conditions of “temperature”, “processing gas flow rate”, and “pressure” in each processing.

  Since the relationship between the film formation condition in the film formation process and the film formation amount has been extensively studied and is already known, in this specification, the relationship between the etching condition in the etching process and the etching amount is as follows. explain. As described above, the etching conditions that affect the etching amount, that is, the etching amount adjusting means by the control device 132 include the temperature of the wafer W during etching, the flow rate of the etching gas, the pressure during etching, and the like.

  For example, the etching amount of the entire etching process can be adjusted by adjusting the temperature of the wafer W during etching. Further, by adjusting the temperature between the zones of the heaters 128a to 128e, the uniformity of the etching amount between the surfaces can be improved. Note that the temperature at the time of etching may be constant, or may be changed so as to be cooled or heated with time. The degree of temperature change differs between the central portion and the peripheral portion of the wafer W. Specifically, since the peripheral portion of the wafer W is close to the heater 128, it tends to be easily heated or cooled. Further, since the central portion of the wafer W is far from the heater 128, it tends to be difficult to be heated or cooled. Therefore, the etching amount in the wafer surface can be adjusted by advancing the etching while changing the temperature.

  In another example, the etching amount of the entire etching process can be adjusted by changing the flow rate of the etching gas. Further, by adjusting the number and arrangement of the gas introduction units 106 and adjusting the flow rate of the etching gas at each gas introduction unit 106, the uniformity of the etching amount between the surfaces and the in-plane uniformity can be improved. .

  In another example, the etching amount of the entire etching process can be adjusted by adjusting the pressure during etching. The adjustment of the pressure during etching is also effective as a means for improving the inter-surface uniformity and the in-plane uniformity of the etching amount.

  Further, it is possible to adjust the etching amount in the depth direction of the pattern 200 by adjusting the flow rate of the etching gas and the pressure during the etching described above.

  As an example, in the depth direction of the pattern 200, an “upper part” in the vicinity of the opening, a “lower part” in the vicinity of the bottom part, and a “middle part” at an arbitrary position between the upper part and the lower part are given. A description will be given as to which part of the etching amount is changed by changing. For example, when the flow rate of the etching gas is changed, the influence on the etching amount at the “upper part” is large, and the influence on the etching amount at the “middle part” and the “lower part” is relatively small. In addition, when the pressure during etching is changed, the influence on the variation in the etching amount at the “middle part” and the “lower part” becomes larger than in the case of the above-described etching gas flow rate.

[Process model]
The control device 132 of the present embodiment optimizes the time distribution of the film formation time and the etching time based on a model stored in advance in the model storage unit 134. An embodiment example of the process model stored in the model storage unit 134 of the control device 132 of this embodiment will be described.

In one embodiment, the model storage unit 134 includes a process model as
The first supply time for supplying the film formation gas in the (first) film formation process, the second supply time for supplying the etching gas in the etching process, and the re-film formation process (second formation time). A processing time-film thickness model representing the effect of the processing time including the combination with the third supply time when supplying the film forming gas in the film processing) on the film thickness of the film forming material on the substrate is stored. ing,
For those skilled in the art, this processing time-film thickness model is a film formation gas supply time-film formation amount model representing the influence of the supply time of the film formation gas on the film formation amount of the film formation material on the wafer. The etching gas supply time can be created using an etching gas supply time-etching amount model or the like that represents the influence of the etching gas supply time on the etching amount of the film forming material on the wafer. Note that the same model may be used as the deposition gas supply time-deposition amount model in the first deposition process and the second deposition process, or different models may be used. In the case of a process in which the film forming speed is substantially the same in the first film forming process and the second film forming process, the same model can be used and an error can be absorbed by a learning function described later. In the case of a process in which the film formation speed differs greatly between the first film formation process and the second film formation process, a model may be created for each process.

  Further, the model storage unit 134 stores other process models relating to the film formation temperature, the flow rate of the film formation gas, and the pressure during the film formation, and other process models relating to the etching temperature, the flow rate of the etching gas, the pressure during the etching, and the like. May be stored.

In one embodiment, the model storage unit 134 includes
Wafer temperature-deposition amount model representing the influence of the temperature of the wafer W on the film formation amount of the film formation substance:
Deposition gas flow rate-deposition amount model representing the influence of the deposition gas flow rate on the deposition amount of the deposition material:
Deposition pressure-deposition amount model representing the influence of the pressure in the processing container 102 on the deposition amount of the deposition material:
May be stored. In this case, the model storage unit has a thermal model,
A thermal model representing the relationship between the temperature of the wafer W in the processing container and the set temperature of the heater 128, that is, the output of the power controller 130 of the heater 128 is stored. As this thermal model, for example, a thermal model for estimating the temperature of the wafer W from the output of a temperature sensor (not shown) arranged on the inner wall of the inner cylinder 102a, the temperature of the monitor wafer W, or the like can be used.

In another embodiment, the model storage unit 134 has a process model as
Wafer temperature-etching amount model representing the influence of the temperature of the wafer W on the etching amount of the film forming material:
Etching gas flow rate-etching amount model representing the influence of the etching gas flow rate on the etching amount of the film forming material:
A pressure-etching amount model representing the influence of the pressure in the processing container 102 on the etching amount of the film forming material:
May be stored.

  By using these models, the controller 132 can use the parameters of “temperature”, “flow rate of process gas”, and “pressure” in addition to the parameter of “time” as the adjusting means. Therefore, the film thickness of the film forming substance on the wafer W can be controlled more strictly.

  Based on the process model stored in the model storage unit 134, the CPU 144 calculates an optimum processing time for at least each of the first film forming process, the etching process, and the second film forming process. To do. Preferably, the film formation temperature and etching temperature of the wafer W, the flow rate of the film formation gas and the flow rate of the etching gas, the pressure in the processing container 102 during film formation, and the pressure in the processing container 102 during etching are calculated. To do. At this time, the calculation of various processing conditions is performed by using an optimization algorithm such as linear programming or quadratic programming, based on the desired film thickness stored in the read process recipe, and in-plane uniformity of the wafer W. The combination of the film formation time and the etching time satisfying the uniformity and the inter-surface uniformity between the wafers W is calculated using an optimization algorithm.

  In the process model and the thermal model described above, the default numerical values may not be optimal depending on the process conditions and the state of the apparatus. For this reason, at least one or more of these models may be provided with a learning function by adding an extended Kalman filter or the like to software for performing various calculations to perform model learning.

  A case where the substrate processing method according to the present embodiment is executed will be described.

  First, a wafer W on which a predetermined pattern has been formed is loaded into the processing container 102 while being placed on the wafer boat 126. Next, when the operator does not use at least the desired film thickness from the side wall of the pattern 200 of the wafer W on the operation panel 148 and the temperature, gas flow rate, and pressure as the adjusting means. Enter the processing conditions.

  Further, when inputting the contents of the process to the operation panel 138, the type of the underlying film, the type of film forming material, and / or other information regarding the pattern 200 of the wafer W (for example, the diameter of the hole or trench, the aspect, etc.) The ratio may be input.

  The CPU 144 determines whether or not there is an input. If there is an input, the CPU 144 reads out the recipe for the film forming process and the recipe for the etching process in response to the input instruction content from the recipe storage unit 136.

  Next, from the process model stored in the model storage unit 134, processing conditions including a film formation time related to the first film formation process, an etching time related to the etching process, and a film formation time related to the second film formation process are calculated. , The recipe is updated. The processing conditions are calculated using an optimization algorithm such as linear programming or quadratic programming (see S300 in FIG. 4).

  Next, based on the determined recipe, the CPU 144 sets the temperature in the processing container 102 to a predetermined film forming temperature by the heater 128 and sets the pressure in the processing container 102 to a predetermined film forming pressure by the opening variable valve 114. Set. Then, the CPU 144 supplies a predetermined amount of film forming gas into the processing container 102 according to the recipe, and executes the first film forming process.

  After a predetermined film forming process time relating to the first film forming process, the supply of the film forming gas is stopped. Then, based on the recipe, the CPU 144 sets the temperature in the processing container 102 to a predetermined etching temperature by the heater 128 and sets the pressure in the processing container 102 to a predetermined etching pressure by the opening variable valve 114. Then, the CPU 144 supplies a predetermined amount of etching gas into the processing container 102 according to the recipe, and executes the first film forming process.

  After a predetermined etching process time related to the etching process, the supply of the etching gas is stopped. Then, based on the recipe, the CPU 144 sets the temperature in the processing container 102 to a predetermined film forming temperature by the heater 128 and sets the pressure in the processing container 102 to a predetermined film forming pressure by the opening degree variable valve 114. Then, the CPU 144 supplies a predetermined amount of film forming gas into the processing container 102 according to the recipe, and embeds the film forming material 204 in the pattern 200.

  After a predetermined film forming process time relating to the second film forming process, the supply of the film forming gas is stopped and the process is completed (see S310 in FIG. 4).

  After the etching process is finished, is the wafer W unloaded, at least one wafer W is taken out from the wafer W placed on the wafer boat 126, and is there a problem with the film thickness of the film forming substance? A determination step for determining whether or not may be performed.

  The CPU 144 may store the calculated processing condition in the RAM 140 as a processing condition for the next processing, and update the recipe. Further, the operator may update the recipe from the operation panel 148 using the calculated processing conditions as processing conditions for the next processing.

  As described above, the vertical substrate processing apparatus and the substrate processing method according to this embodiment can simultaneously process a large number of wafers W as one batch. Further, by calculating the optimal time distribution of the film formation process and the etching process by the control device 132, the film formation amount and the etching amount can be adjusted simultaneously. As a result, it is possible to easily embed the film-forming substance 204 in the recesses of the pattern 200 without voids with a short TAT while minimizing human labor and time.

DESCRIPTION OF SYMBOLS 100 Vertical substrate processing apparatus 102 Processing container 104 Manifold 106 Gas introduction part 108 Gas exhaust part 110 Piping 112 Vacuum pump 114 Opening variable valve 116 Piping 118 Furnace opening 120 Cover body 122 Lifting mechanism 125 Thermal insulation cylinder 126 Wafer boat 128 Heater 130 Electric power Controller 132 Controller 134 Model storage unit 136 Recipe storage unit 138 ROM
140 RAM
142 I / O port 144 CPU
146 Bus 148 Operation panel 200 Pattern 202 Base film 204 Film forming material W Semiconductor wafer

Claims (8)

A processing container capable of arranging a substrate holder for holding a plurality of substrates in multiple stages at a predetermined interval; a heater for heating the inside of the processing container;
A processing gas introduction part for introducing a film forming gas and an etching gas into the processing container;
An exhaust section for exhausting the inside of the processing container;
A first film forming process on a substrate on which a predetermined concavo-convex pattern is formed in advance, using a vertical substrate processing apparatus having a control device and a control device for controlling the operation of the vertical substrate processing apparatus. A substrate processing method for embedding a film-forming substance in a recess of the concavo-convex pattern by an etching process and a second film-forming process,
The substrate processing method includes:
A first film-forming condition including a first film-forming time of the first film-forming process, so that the film-forming substance is buried without voids in the recess after the second film-forming process; The control device distributes the optimal time distribution for the first etching condition including the first etching time of the etching process and the second film forming condition including the second film forming time of the second film forming process. Calculating step,
A process step of performing the first film forming process, the first etching process, and the second film forming process on the substrate based on the calculated optimal time distribution ;
A substrate processing method. The calculation step includes
The depth direction of the uneven pattern, wherein a first position near the opening of the concave-convex pattern, and a second position near the bottom of the concave-convex pattern, of the first position and the second position A third position between the first deposition time and the amount of deposition, a relationship between the first etching time and the amount of etching, and the second position, respectively. Based on the relationship between the deposition time and the deposition amount, the control device calculates,
The substrate processing method according to claim 1. The first etching condition is such that the etching amount at the first position is larger than the etching amount at the second position and the third position.
The substrate processing method according to claim 2. The first film formation condition includes a film formation temperature, a flow rate of the film formation gas, and a pressure in the processing container,
The first etching conditions include an etching temperature, a flow rate of the etching gas, and a pressure in the processing container,
The second film formation condition includes a film formation temperature, a flow rate of the film formation gas, and a pressure in the processing container.
The substrate processing method as described in any one of Claims 1 thru | or 3. A processing container capable of arranging a substrate holder for holding a plurality of substrates in multiple stages at a predetermined interval; a heater for heating the inside of the processing container;
An etching gas introduction part for introducing a film forming gas and an etching gas into the processing container;
An exhaust section for exhausting the inside of the processing container;
Film forming process and etching process are performed a predetermined number of times on a substrate on which a predetermined concavo-convex pattern has been formed in advance using a vertical substrate processing apparatus having the above and a control device for controlling the operation of the vertical substrate processing apparatus It is a substrate processing method of repeatedly processing, embedding a film-forming substance in a concave portion of the concave- convex pattern through a film-forming process again after the repeating process,
Each of the film formation conditions including the film formation time in each of the film formation processes, and each of the etching processes so that the film formation material is filled without voids in the recess after the film formation process after the repetition process. In the calculation step, the control device calculates the optimal time distribution for the etching conditions including the etching time,
A process step of performing each of the film forming process and each of the etching processes on the substrate based on each of the calculated optimal time distributions ;
A substrate processing method. A processing container capable of arranging a substrate holder for holding a plurality of substrates in multiple stages at a predetermined interval; and
A heater for heating the inside of the processing container;
A processing gas introduction part for introducing a film forming gas and an etching gas into the processing container;
An exhaust section for exhausting the inside of the processing container;
The a, in advance the substrate in which a predetermined concave-convex pattern is formed, the film forming process of the film forming material, by sequentially performing the re-deposition process of etching process and the film forming material of the film forming material, the uneven A control device capable of controlling the operation of a vertical substrate processing apparatus that embeds the film-forming substance in a recess of a pattern,
The control device has a model storage unit,
The model storage unit includes a first supply time for supplying the film forming gas in the film forming process, a second supply time for supplying the etching gas in the etching process, and the regeneration. A processing time-film thickness model representing the influence of the processing time including the combination with the third supply time when supplying the film forming gas in the film processing on the film thickness of the film forming material on the substrate. are stored,
Based on the processing time-film thickness model stored in the model storage unit, an optimal time distribution for the film formation process, the etching process, and the re-film formation process is calculated.
Control device. The model storage unit further includes:
A first process model representing an influence of a temperature of the substrate on a film formation amount of the film formation material;
A second process model representing an influence of a flow rate of the film forming gas on a film forming amount of the film forming material;
A third process model representing the effect of the pressure in the processing container on the film formation amount of the film formation material;
A thermal model representing the relationship between the temperature of the substrate and the set temperature of the heater;
Is stored, the control device according to claim 6. The model storage unit further includes:
A fourth process model representing the effect of the temperature of the substrate on the etching amount of the film-forming substance;
A fifth process model representing the influence of the flow rate of the etching gas on the etching amount of the film-forming substance;
A sixth process model representing an effect of the pressure in the processing container on the etching amount of the film-forming substance;
Is stored, the control device according to claim 6 or 7.

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