JP2011029592A - Surface processing simulation device, controller for surface processing apparatus and surface processing system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To calculate optimal conditions of a raw material fluid for surface processing in vertical rotary surface processing that uses pumpability. <P>SOLUTION: A surface processing simulation device 20 for a vertical rotary surface processing apparatus 10 stores a model calculation program 36 that calculates velocity distribution of the raw material fluid 18 by applying a pumpability model to a storage portion 38. A CPU 30 includes: a parameter acquisition processing portion 42 for inputting and acquiring surface processing parameters; a model calculation portion 44 that calculates the velocity distribution of the raw material fluid 18 to a substrate 16 by applying the acquired surface processing parameters to the model calculation program 36; an optimal flow rate calculation processing portion 46 that calculates the optimal flow rate of the raw material fluid based on the calculated data of the velocity distribution and device parameters; and a flow rate correction processing portion 48 that corrects the optimal flow rate based on the device shape parameters. The productivity flow rate where the optimal flow rate is reduced is determined from the productivity viewpoint. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a surface treatment simulation apparatus and a surface treatment apparatus controller, and in particular, calculates an optimum gas condition in a surface treatment apparatus that generates a film on a substrate by supplying a surface treatment raw material fluid to a rotating substrate. The present invention relates to a simulation device, a surface treatment device control device, and a surface treatment system thereof.

  For example, in order to manufacture a semiconductor element or the like, a raw material fluid such as an appropriate reaction gas is supplied onto the substrate to form a semiconductor layer, an insulating film, a conductor layer, or the like on the substrate, or the surface of the substrate is Etching, cleaning, or forming a coating material is performed. Such treatment is widely performed in addition to the manufacture of semiconductor elements, and these treatments can be referred to as surface treatment in a broad sense, and an apparatus that performs this surface treatment can be referred to as a surface treatment device in a broad sense.

  For example, an epitaxial apparatus for epitaxially growing a semiconductor layer on a semiconductor wafer or an insulator wafer, a vapor deposition (CVD) apparatus for depositing an insulating film such as an appropriate oxide film on the semiconductor wafer, or a semiconductor wafer formed on the semiconductor wafer A dry etching apparatus or the like that removes the formed thin film or the like is a surface treatment apparatus in a broad sense.

  The surface treatment apparatus includes a horizontal type that supplies the surface treatment raw material fluid in parallel to the surface direction of the substrate and a vertical type that supplies the surface treatment raw material fluid in a direction substantially perpendicular to the surface of the substrate. In the latter case, in order to ensure the uniformity of the surface treatment, the substrate is often rotated about an axis in a direction perpendicular to the surface.

  Such a vertical rotary surface treatment apparatus is used for various purposes, but has the following common features. That is, (1) A processing object having various shapes of processing surfaces is placed in the central portion and rotated. (2) Gas or liquid as a raw material flows from above, and the rotation of the processing object A boundary layer is formed near the surface. (3) Phase transfer or chemical reaction occurs in the surface or the boundary layer, and the effect of surface treatment is obtained. (4) The fluid is processed from the center by centrifugal force later. Outflow to the outer edge.

  As described above, a feature of the vertical rotary surface treatment apparatus is that the physical quantity distribution such as the boundary layer thickness, temperature, and concentration is uniform in the boundary layer formed by the rotation of the workpiece. In this uniform operating environment, uniform physical and chemical reactions can be obtained on the surface, and the uniformity of the product is improved.

  For example, in Patent Document 1, in a vapor phase growth apparatus that forms an epitaxial growth layer on the surface of a semiconductor substrate, by rotating the wafer at a high speed of several hundred revolutions per minute, the atmospheric pressure in the vicinity of the wafer is reduced, and the wafer from above. The reaction gas to be sent is drawn to the wafer surface (pump effect), and the boundary layer directly above the wafer surface where the epitaxial growth reaction proceeds is made uniform and thinned by centrifugal force, increasing the supply efficiency of the reaction gas and increasing the epitaxial growth rate. It is stated that it will be made easier.

Regarding the analysis of the pump effect, Non-Patent Document 1 gives an example of an exact solution of the Navier-Stokes equation for a flow around a disk rotating at a constant angular velocity ω around an axis perpendicular to the flat plate surface in a fluid. It is stated. Here, the kinematic viscosity coefficient ν of the fluid indicates that the boundary layer thickness can be approximated to (ν / ω) ^1/2, and the radial velocity u, circumferential velocity v, axial velocity w of the disk For pressure p, it is shown to solve a quaternary simultaneous partial differential equation normalized by z / (ν / ω) ^1/2 , which is a dimensionless distance z along the axial direction.

  According to the calculation result, the axial velocity w of the fluid due to the pump effect decreases as the distance along the axial direction approaches the disc and becomes zero on the disc surface, and the radial velocity u is It has been shown to have a maximum velocity distribution that is zero on the surface of the disk, but gradually increases with increasing distance from the disk along the axial direction, and returns to zero again when further away from the disk.

  Non-Patent Document 1 does not consider the effect of temperature, but Non-Patent Document 2 discloses a thermal energy equation that takes into account the thermal conductivity of a fluid as a silicon formation technique on a rotating disk. In addition to the quaternary simultaneous partial differential equation described in the above, it is described to solve a quinary simultaneous partial differential equation.

JP-A-9-63966

Dr. Hermann Schlicting (Translated by Dr. JK Kestin); Boundary-Layer Theory; Seventh Edition; USA; Mc Graw-Hill Book Company; 1979; p102-104 Richard Pollard et. al. Silicon Deposition on a Rotating Disk; Electrochem. Soc. Solid-State Science and Technology; USA; March 1980; vol. 127, no. 3; p744-745

  As described in Patent Document 1, in the vertical rotary surface treatment apparatus, the boundary layer is effectively formed by the pump effect, and improvement in uniformity of the surface treatment and improvement in productivity are expected.

  As described above, the vertical rotary surface treatment apparatus uses boundary layer formation by the pump effect, but the actual manufacturing conditions are set uniformly because the flow path shape differs depending on the size and shape of the surface treatment apparatus. In order to obtain an appropriate surface treatment, the number of rotations of the substrate, the temperature of the substrate, the flow rate of the raw material fluid, and the like are varied in various ways, and an appropriate one is selected. That is, actual manufacturing conditions are set based on experimental data.

  An object of the present invention is to provide a surface treatment simulation apparatus capable of calculating the optimum conditions of the surface treatment raw material fluid in the vertical rotary surface treatment using the pump effect, and the surface treatment capable of setting the optimum conditions of the surface treatment raw material fluid. An apparatus control device, and a surface treatment system including the vertical rotary surface treatment device and the surface treatment device control device are provided.

  The surface treatment simulation apparatus according to the present invention is a simulation for calculating optimum gas conditions in a vertical rotary surface treatment apparatus that supplies a surface treatment raw material fluid to a rotating substrate in a substantially vertical direction and performs surface treatment on the substrate. An apparatus for obtaining a surface treatment parameter including a device parameter relating to a shape of the surface treatment device, a raw material fluid parameter relating to a characteristic of the raw material fluid, and a pump effect model of a flow around a disk rotating in the fluid And a storage unit for storing a model calculation program for calculating an axial velocity distribution that is a characteristic with respect to a distance along the axial direction of the axial velocity of the raw material fluid, with the direction perpendicular to the rotating disk surface as the axial direction, Applying the surface treatment parameters acquired by the acquisition means to the model calculation program, Based on the model calculation means for calculating the axial velocity distribution of the body, the calculation data of the axial velocity distribution of the raw material fluid relative to the substrate, and the apparatus parameters, it is optimal for the uniformity of the surface treatment generated on the substrate. And an optimum flow rate calculating means for calculating the raw material fluid flow rate.

Further, in the surface treatment simulation apparatus according to the present invention, the optimum flow rate calculating means is configured to calculate the axial velocity w (∞) calculated when the axial distance is infinite with respect to the axial velocity distribution of the raw material fluid with respect to the substrate. Q = A × w (∞), which is a value obtained by multiplying the surface area A _{1 of the} substrate or the cross-sectional area A ₂ of the inlet of the raw material fluid in the surface treatment apparatus, whichever is larger, is calculated as the optimum flow rate. preferable.

  In the surface treatment simulation apparatus according to the present invention, in addition to calculating the axial velocity distribution of the raw material fluid, the storage unit further sets the radial direction velocity of the raw material fluid with the radial direction of the rotating disk as the radial direction. A model calculation program for calculating a radial velocity distribution, which is a characteristic with respect to a distance along the axial direction, is stored, and the model calculation means further includes a source fluid for the substrate in addition to the calculation of the axial velocity distribution of the source fluid for the substrate. It is preferable to further include a flow rate correction unit that further calculates the radial flow velocity distribution of the raw material fluid and corrects the optimum flow rate based on the calculation data of the radial flow velocity distribution of the raw material fluid with respect to the substrate and the apparatus parameters.

Further, in the surface treatment simulation apparatus according to the present invention, the flow rate correction means increases the radial speed and decreases again as the radial speed distribution of the raw material fluid with respect to the substrate increases as the distance along the axial direction increases. The height calculated as the axial distance when the speed is equal to or less than a predetermined threshold speed is defined as the radial outflow height h _0, and the raw material fluid outlet in the surface treatment apparatus extends along the axial direction from the surface of the substrate. It is preferable to correct the optimum flow rate according to h with respect to h ₀ , where h is the opening height.

  Further, in the surface treatment simulation apparatus according to the present invention, the flow rate correcting means increases the maximum velocity at which the radial velocity increases and becomes maximum as the distance along the axial direction increases in the radial velocity distribution of the raw material fluid with respect to the substrate. (Max), S (edge) with respect to u (max), where S (edge) is the distance that the raw material fluid strikes along the radial direction of the substrate from the outer peripheral edge of the substrate at the outlet of the raw material fluid in the surface treatment apparatus Accordingly, it is preferable to correct the optimum flow rate.

  The control device for a surface treatment apparatus according to the present invention supplies an optimum gas to a vertical rotary surface treatment apparatus that supplies a surface treatment raw material fluid to a rotating substrate in a substantially vertical direction and performs surface treatment on the substrate. A control device for setting conditions, an acquisition unit for acquiring a surface treatment parameter including a device parameter relating to a shape of the surface treatment device and a raw material fluid parameter relating to a characteristic of the raw material fluid; and a periphery of a disk rotating in the fluid Stores a model calculation program that uses the flow pump effect model and calculates the axial velocity distribution, which is a characteristic of the axial velocity of the raw material fluid with respect to the distance along the axial direction, with the direction perpendicular to the rotating disk surface as the axial direction. And applying the surface treatment parameters acquired by the acquisition means to the model calculation program, the axial speed of the raw material fluid relative to the substrate Based on the model calculation means for calculating the distribution, the calculation data of the axial velocity distribution of the raw material fluid relative to the substrate, and the apparatus parameters, the optimal raw material fluid flow rate is calculated for the uniformity of the surface treatment generated on the substrate And an optimum flow rate setting means for setting this as the optimum flow rate.

  In addition, a surface treatment system according to the present invention includes a housing part that forms a cylindrical peripheral wall, a sample holder that is provided inside the housing part and holds a substrate that is an object to be surface-treated, A rotation mechanism that rotates the sample holding table, a source fluid supply channel that is provided above the sample holding table in the casing and supplies a source fluid to the sample of the sample holding table, and a sample in the casing A sample provided as a used fluid after the surface treatment is performed on the substrate while the raw material fluid is provided on the side of the holding table and supplied as a vertical flow from above the sample holding table toward the substrate. An outflow passage section for flowing out from the side of the holding table, and a control device for setting optimum gas conditions. The control device includes device parameters relating to the shape of the surface treatment device and raw material fluid parameters relating to the characteristics of the raw material fluid. Including surface treatment Using the acquisition means for acquiring the parameters and the pump effect model of the flow around the rotating disk in the fluid, the direction perpendicular to the rotating disk surface is the z direction, and the z direction flow velocity of the source fluid is along the z direction. A storage unit that stores a model calculation program for calculating a z-direction flow velocity characteristic that is a characteristic with respect to a distance, and a surface treatment parameter acquired by the acquisition unit are applied to the model calculation program, so that the z-direction flow velocity characteristic of the raw material fluid with respect to the substrate Based on the model calculation means for calculating the flow rate, the calculation data of the z-direction flow velocity characteristic of the raw material fluid with respect to the substrate, and the apparatus parameters, the optimal raw material fluid flow rate is calculated for the uniformity of the surface treatment generated on the substrate. And an optimum flow rate setting means for setting this as the optimum flow rate.

  Further, in the surface treatment system according to the present invention, the control device obtains in advance a flow rate-variation relationship that is a relationship between an arbitrary flow rate smaller than the optimum flow rate and a variation amount with respect to the uniformity of the surface treatment, from the viewpoint of productivity. With the allowable variation set as the threshold variation, the flow rate corresponding to the threshold variation is previously obtained as the threshold flow rate based on the flow rate-variation relationship, and the flow rate that is equal to the threshold flow rate is reduced by reducing the flow rate from the optimal flow rate. It is preferable to include productivity flow rate setting means for setting as follows.

  Further, in the surface treatment system according to the present invention, the control device obtains in advance a flow rate-variation relationship that is a relationship between an arbitrary flow rate smaller than the optimum flow rate and a variation amount with respect to the uniformity of the surface treatment, from the viewpoint of productivity. Assuming the allowable variation to be set as the threshold variation, the flow rate corresponding to the threshold variation is obtained as the threshold flow rate based on the flow rate-variation relationship, and the degree of backflow generated on the substrate at an arbitrary flow rate smaller than the optimum flow rate Define the backflow penetration length, and obtain the flow rate-backflow penetration length relationship, which is the relationship between the flow rate and the backflow penetration length, in advance. Based on the relationship between the flow rate and the backflow penetration length, the backflow penetration length is obtained for any flow rate that is less than the optimum flow rate. Further reducing the flow rate is shorter than the penetration depth, it is preferred to include a productivity rate setting means for setting a flow rate backflow penetration depth obtained is equal to the threshold reflux penetration length as productivity rate, a.

  With at least one of the above-described configurations, the surface treatment simulation apparatus acquires the surface treatment parameters, uses the pump effect model of the flow around the rotating disk in the fluid, and sets the direction perpendicular to the rotating disk surface in the axial direction. As an example, a surface processing parameter is applied to a model calculation program for calculating an axial velocity distribution which is a characteristic of the axial velocity of a raw material fluid with respect to a distance along the axial direction, thereby calculating the axial velocity distribution of the raw material fluid relative to the substrate. . Based on the calculated result, an optimal raw material fluid flow rate is calculated for the uniformity of the surface treatment generated on the substrate. As the pump effect model, a model in which the temperature effect is incorporated in the model described in Non-Patent Document 1 can be used.

  Since the result calculated based on the pump effect model shows the axial velocity distribution of the raw material fluid with respect to the substrate, if the flow rate in the surface treatment apparatus is set to match the axial velocity distribution of this pump effect, A boundary layer as the pump effect model is formed, and the uniformity of the surface treatment can be ensured. According to the above configuration, the velocity that forms the boundary layer according to the pump effect model is calculated. Based on this result and the apparatus parameters, the optimum raw material fluid flow rate is calculated for the uniformity of the surface treatment. Is done.

Further, in the surface treatment simulation apparatus, the surface area A _{1 of} the substrate or the surface treatment apparatus has an axial velocity w (∞) calculated when the axial distance is infinite with respect to the axial velocity distribution of the raw material fluid with respect to the substrate. Q = A × w (∞), which is a value obtained by multiplying the larger area A of the cross-sectional area A ₂ of the inlet of the raw material fluid, is calculated as the optimum flow rate. By doing so, the flow rate in the surface treatment apparatus can be matched to the axial velocity distribution of the pump effect.

  In addition to the calculation of the axial velocity distribution of the raw material fluid relative to the substrate, the surface treatment simulation apparatus further calculates the radial velocity distribution of the raw material fluid relative to the substrate, and based on this and the apparatus parameters, the optimum flow rate is calculated. Correct. In the vertical rotary surface treatment apparatus, the raw material fluid flows along the surface of the substrate, and the raw material fluid flows out toward the outside of the outer periphery of the substrate. If the flow path shape of the outlet is inadequate depending on the apparatus, the uniformity of the boundary layer may be disturbed, for example, the flow of the raw material fluid flows backward or obstructs the flow. According to the above configuration, the radial velocity distribution according to the pump effect model is calculated. Based on this result and the apparatus parameters, the optimum raw material fluid flow rate is corrected for the uniformity of the surface treatment.

Further, in the surface treatment simulation apparatus, the radial velocity increases as the radial velocity distribution of the raw material fluid with respect to the substrate increases along the axial direction, decreases to a maximum velocity, and decreases below a predetermined threshold velocity. The height calculated as the axial distance at this time is defined as the radial outflow height h _0, and the opening height along the axial direction from the surface of the substrate at the outlet of the raw material fluid in the surface treatment apparatus is defined as h _0. The optimum flow rate is corrected according to h with respect to. By doing in this way, it can be set as the fluid outflow rate suitable for a pump effect model, and the uniformity of surface treatment is secured.

  Further, in the surface treatment simulation apparatus, the radial velocity increases as the distance along the axial direction of the radial velocity distribution of the raw material fluid with respect to the substrate increases, and the maximum maximum velocity is u (max). With respect to the outlet of the raw material fluid, the distance at which the raw material fluid strikes from the outer peripheral edge of the substrate along the radial direction of the substrate is S (edge), and the optimum flow rate is corrected according to S (edge) with respect to u (max). By doing in this way, it can be set as the fluid outflow rate suitable for a pump effect model, and the uniformity of surface treatment is secured.

  In addition, according to at least one of the above-described configurations, the controller for the surface treatment apparatus obtains the surface treatment parameters, uses the pump effect model of the flow around the disk rotating in the fluid, and is perpendicular to the rotating disk surface. A surface treatment parameter is applied to a model calculation program for calculating an axial velocity distribution, which is a characteristic of the axial velocity of a raw material fluid with respect to a distance along the axial direction, where the direction is an axial direction. Calculate the distribution. Based on the calculated result, an optimal raw material fluid flow rate is calculated for the uniformity of the surface treatment generated on the substrate, and this is set as the optimal flow rate.

  Since the result calculated based on the pump effect model shows the axial velocity distribution of the raw material fluid with respect to the substrate, if the flow rate in the surface treatment apparatus is set to match the axial velocity distribution of this pump effect, A boundary layer as the pump effect model is formed, and the uniformity of the surface treatment can be ensured. According to the above configuration, the speed that forms the boundary layer according to the pump effect model is calculated. Based on this result and the apparatus parameters, the optimum raw material fluid flow rate is calculated for the uniformity of the surface treatment. This can be set as the optimum flow rate.

  According to at least one of the above configurations, the surface treatment system includes a surface treatment device and a control device. In the surface treatment apparatus, a sample holding base is provided inside a casing portion that forms a cylindrical peripheral wall, and the raw material fluid is supplied as a vertical flow from the raw material fluid supply flow path portion provided on the upper side of the casing portion. Is supplied to the substrate on the sample holder, flows along the surface of the substrate, performs surface treatment on the substrate, and performs surface treatment from the outflow channel on the side of the sample holder in the casing. Spent fluid flows out. Further, the casing unit includes a rotation mechanism that rotates the sample holding table. In the control device, the surface treatment parameters are acquired, and the pump effect model of the flow around the rotating disk in the fluid is used. The axial direction of the raw material fluid is defined as the axial direction perpendicular to the rotating disk surface. A surface treatment parameter is applied to a model calculation program for calculating an axial velocity distribution, which is a characteristic of the velocity with respect to a distance along the axial direction, to calculate an axial velocity distribution of the raw material fluid with respect to the substrate. Based on the calculated result, an optimal raw material fluid flow rate is calculated for the uniformity of the surface treatment generated on the substrate, and this is set as the optimal flow rate.

  Here again, the result calculated based on the pump effect model shows the axial velocity distribution of the raw material fluid relative to the substrate, so the flow rate in the surface treatment device is set to match the axial velocity distribution of this pump effect. In this case, a boundary layer is formed according to the pump effect model, and the uniformity of the surface treatment can be ensured. According to the above configuration, the speed that forms the boundary layer according to the pump effect model is calculated. Based on this result and the apparatus parameters, the optimum raw material fluid flow rate is calculated for the uniformity of the surface treatment. This can be set as the optimum flow rate.

  Also, in the surface treatment system, a flow rate-variation relationship that is the relationship between an arbitrary flow rate less than the optimum flow rate and the variation amount for the uniformity of the surface treatment is obtained in advance, and the permissible variation set from the viewpoint of productivity is changed to the threshold variation. The flow rate corresponding to the threshold variation is obtained in advance as the threshold flow rate based on the flow rate-variation relationship, the flow rate is decreased from the optimum flow rate, and the flow rate equal to the threshold flow rate is set as the productivity flow rate. As a result, the flow rate can be reduced from the optimum flow rate with little variation, and the productivity can be secured.

  Also, in the surface treatment system, a flow rate-variation relationship that is the relationship between an arbitrary flow rate less than the optimum flow rate and the variation amount for the uniformity of the surface treatment is obtained in advance, and the permissible variation set from the viewpoint of productivity is changed to the threshold variation. The flow rate corresponding to the threshold variation is obtained as the threshold flow rate based on the flow rate-variation relationship, and the reverse flow penetration length is defined for the degree of the reverse flow generated on the substrate at an arbitrary flow rate smaller than the optimum flow rate. The flow rate-reverse flow penetration length relationship, which is the relationship between the flow rate and the reverse flow penetration length, is obtained in advance, and the reverse flow penetration length corresponding to the threshold flow rate is obtained as the threshold reverse flow penetration length based on this flow rate-reverse flow penetration length relationship. Then, based on this flow rate-reverse flow penetration length relationship, the reverse flow penetration length is obtained for an arbitrary flow rate smaller than the optimum flow rate, and when the obtained reverse flow penetration length is shorter than the threshold reverse flow penetration length, the flow rate is further reduced. A flow rate at which the obtained backflow penetration length becomes equal to the threshold backflow penetration length is set as the productivity flow rate. Thus, since the productivity flow rate can be set in association with the backflow penetration length, the flow rate can be reduced from the optimum flow rate with almost no backflow, and the productivity can be ensured.

It is a figure explaining the pump effect model used as the foundation of the present invention. It is a figure which shows the speed distribution characteristic in the pump effect model used as the foundation of this invention. It is a figure which shows the structure of the surface treatment simulation apparatus and control apparatus for surface treatment apparatuses in embodiment which concerns on this invention. 5 is a flowchart showing a procedure for calculating an optimum flow rate in the embodiment according to the present invention. In embodiment which concerns on this invention, it is a figure explaining the mode of the optimal flow volume calculation of a sealing type surface treatment apparatus. In embodiment which concerns on this invention, it is a figure explaining the mode of the optimal flow volume calculation of an open type surface treatment apparatus. In embodiment which concerns on this invention, it is a figure which shows the mode of the optimal flow volume calculated from a pump effect model. In embodiment which concerns on this invention, it is a figure explaining the mode of the shape of an outflow port. In embodiment which concerns on this invention, it is a figure explaining the mode of radial direction velocity distribution. In embodiment which concerns on this invention, it is a figure explaining the mode of a flow in case a setting flow volume is insufficient. In embodiment which concerns on this invention, it is a figure explaining the mode of a flow when setting flow volume is optimal. In embodiment which concerns on this invention, it is a figure explaining the mode of a flow when setting flow volume is excessive. In embodiment which concerns on this invention, it is a figure explaining the relationship between the crystal growth rate distribution and flow volume in the epitaxial growth as an example of surface treatment. It is a figure which shows the structure of the surface treatment system in embodiment which concerns on this invention. It is a figure explaining the example of the flow at the time of the optimal flow volume setting in the surface treatment system of embodiment which concerns on this invention. In the surface treatment system of an embodiment concerning the present invention, it is a figure explaining the situation of the backflow which arises at the set flow rate smaller than the optimal flow rate. In the surface treatment system according to the embodiment of the present invention, the relationship between the flow rate and the film thickness variation, the relationship between the flow rate and the backflow penetration length are shown, and the state where the productivity flow rate can be set using the threshold flow rate smaller than the optimum flow rate is explained. It is a figure to do. In the surface treatment system of an embodiment concerning the present invention, it is a figure explaining the relation between film thickness variation and backflow penetration length. It is a flowchart which shows the procedure of productivity flow volume setting in the surface treatment system of embodiment which concerns on this invention. In the surface treatment system of embodiment which concerns on this invention, it is a figure explaining the mode of the range of the flow volume which can perform productivity flow setting.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Hereinafter, the surface treatment simulation apparatus will be mainly described. However, since the surface treatment process can be controlled using the result obtained by the surface treatment simulation, the contents can be applied to the surface treatment apparatus controller as it is. Moreover, it can also be comprised as a surface treatment system including a surface treatment apparatus and the control apparatus for surface treatment apparatuses.

  In the following, a silicon single crystal epitaxial growth apparatus will be described as an example of the surface treatment apparatus, but this is merely an example. Here, a raw material fluid such as an appropriate reaction gas is supplied onto the substrate to form a semiconductor layer, an insulating film, a conductor layer, etc. on the substrate, or the surface of the substrate is etched or cleaned. Alternatively, it may be a surface treatment apparatus that forms a coating material.

In the following description, a reaction gas as a mixture of SiHCl ₃ + H ₂ will be described as a raw material fluid for surface treatment for silicon single crystal growth, but this is the case for the convenience of the surface treatment apparatus. However, other types of reaction gases may be used depending on the content of the surface treatment. Further, it may be a raw material fluid such as another liquid. For example, an atomized etching solution, a resist solution, or the like may be used. In the following, it is described that the silicon single crystal is grown by heating the substrate, but this is an example of surface treatment, and the surface treatment raw material fluid is applied to the rotating substrate regardless of whether the substrate is heated or not. May be used as long as it is a surface treatment that generates a film on the substrate.

  Note that materials, dimensions, shapes, temperatures, flow rates, and the like described below are exemplifications for explanation, and can be appropriately changed according to the content of the surface treatment.

  Below, the same code | symbol is attached | subjected to the same element in all the drawings, and the overlapping description is abbreviate | omitted. In the description in the text, the symbols described before are used as necessary.

  First, the pump effect which is the basis of the present invention will be described according to the above-mentioned Non-Patent Document 1, and then the configuration and operation of the surface simulation apparatus according to the embodiment of the present invention will be described.

  As mentioned above, Non-Patent Document 1 is a textbook of boundary layer theory, and Chapter 5 describes some examples of exact solutions of the Navier-Stokes equations. The surrounding flow is described as follows.

  That is, in the fluid, the flow in the vicinity of the disk rotating at a constant angular velocity ω around the axis perpendicular to the flat plate surface is carried by friction, and flows to the outer peripheral side by centrifugal force. It is a three-dimensional flow. In three dimensions, the r direction of the disc is the radial direction, the φ direction that is the tangential direction of the outer periphery of the disc is the circumferential direction, and the z direction that is perpendicular to the flat plate surface of the disc is the axial direction. Let the velocity be u, v, w.

ここで、ｐは圧力、ρは流体の密度、νは流体の動粘性係数である。なお、流体の静粘性係数をμとして、μ＝ρνの関係がある。 First, by considering an infinitely large rotation plane, the end effect of the finite diameter D = 2R of the disc can be ignored. From the symmetry of the disc, the Navier-Stokes equation can be expressed as ).

Here, p is the pressure, ρ is the density of the fluid, and ν is the kinematic viscosity coefficient of the fluid. Note that there is a relationship of μ = ρν where μ is the static viscosity coefficient of the fluid.

  FIG. 1 schematically shows the directions of r, φ, z, u, v, and w and the flow of fluid for a disk 50 that rotates at a constant angular velocity ω. Here, the pump effect means that the fluid is sucked up from the disc 50 in the axial direction by the rotation of the disc 50, and therefore, the z-axis 52 that is the axial direction is given a reference numeral.

In the state of FIG. 1, assuming that there is no slip on the wall, the boundary condition related to equation (1) is given by equation (2).

Here, the thickness δ of the fluid layer carried by the rotating disc 50 is estimated. This thickness δ can be considered as the thickness of the boundary layer that contributes to the surface treatment on the surface of the disk 50. For example, by considering the balance between centrifugal force and shear force in the element at the radius r, δ can be approximated by Equation (3).

つまり、式（５）で示される無次元数で円板５０から垂直方向の距離を示すことにする。

Therefore, the distance z along the z-axis 52 from the disc 50 can be made dimensionless by this δ, as shown in Expression (4).

That is, the distance in the vertical direction from the disk 50 is represented by a dimensionless number represented by the equation (5).

Using this dimensionless number, the speeds u, v, w and pressure p can be rewritten as shown in equation (6).

Applying these equations to equation (1) and rewriting the terms corresponding to the velocities u, v, w and pressure p with the non-dimensional functions F, G, H, P, four simultaneous ordinary differential equations ( 7).

The boundary condition can be expressed by equation (8).

  The first approximate solution of equation (7) can be obtained by numerical integration. The result is shown in FIG. The horizontal axis in FIG. 2 is a dimensionless distance ζ in units of δ, and the vertical axis is F, G, and H, as shown in Expression (5). Here, F, G, and H indicate velocity distributions about ζ in the radial direction, the circumferential direction, and the axial direction of the disc 50, respectively. That is, FIG. 2 is a diagram showing a radial velocity distribution, a circumferential velocity distribution, and an axial velocity distribution for ζ.

  From the result of FIG. 2, it can be seen that H, which indicates the axial velocity w of the fluid due to the pump effect, decreases as the distance z along the axial direction approaches the disc 50 and becomes zero on the surface of the disc 50. In other words, the fluid flows so as to be sucked into the surface of the disk 50 along the axial direction. This phenomenon corresponds to what is called a pump effect.

  From this, it can be seen that in order to form δ as in the above theoretical calculation, the axial velocity w of the fluid when z is ∞ may be set as the calculated value. That is, by setting the flow rate of the fluid so as to match the axial velocity w (∞) of the fluid when z is ∞, the fluid can flow on the surface of the disk 50 with a thickness of δ. Therefore, in order to obtain the theoretical flow of the pump effect, a circle rotating a flow rate Q = Aw (∞) obtained by multiplying the speed of w (∞) shown in FIG. 2 by the area A of the surface perpendicular to the flow path. It can be seen that it is sufficient to supply from directly above the plate 50.

  Further, in the result of FIG. 2, F indicating the radial velocity u of the fluid due to the pump effect is zero on the surface of the disk 50, but gradually increases as the distance z along the axial direction increases away from the disk 50. Further, it is shown that it has a velocity distribution having a maximum velocity u (max) that returns to zero again when it is further away from the disk 50. That is, it can be seen that fluid flows out from the outer periphery of the disk 50 in the radial direction, but the range in the axial direction is about 4 in the dimensionless distance ζ in the example of FIG.

  From this, in order to form δ as in the above theoretical calculation, the shape of the outlet on the outer peripheral side of the disk 50 does not interfere with the axial range in which fluid flows radially from the outer periphery of the disk 50. It turns out that it is necessary to do so. If the interference occurs, the fluid outflow flow as theoretically does not occur, and the boundary layer flow as theoretically calculated cannot be secured. It can also be seen that there is a need for a margin for securing u (max) in the radial direction of the shape of the outlet on the outer peripheral side of the disk 50. If the dimension of the outlet in the radial direction is narrow, the fluid flowing out in the radial direction becomes an obstacle to the fluid flow as theoretically calculated, and the boundary layer flow as theoretically calculated cannot be secured.

  Thus, from the theoretical calculation of the pump effect described in Non-Patent Document 1, the route for obtaining the optimum flow rate in the vertical rotary surface treatment device can be found, and the route for obtaining the degree of the influence on the device shape, particularly the flow channel shape. I understand.

  FIG. 3 is a diagram for explaining the configuration of the surface treatment simulation device 20 for obtaining the optimum flow rate of the vertical rotary surface treatment device 10 using the result of the theoretical calculation of the pump effect.

  Here, the vertical rotary surface treatment apparatus 10 is a silicon epitaxial growth apparatus, and is an apparatus having a configuration in which a disk-shaped sample holder 14 is provided inside a casing portion 12 that forms a cylindrical peripheral wall. is there. A silicon wafer as a substrate 16 on which a silicon single crystal is grown can be held on a disk-like sample holder 14 by a sample holding mechanism (not shown).

  Further, the disk-shaped sample holder 14 can be heated to a predetermined temperature by a heating mechanism (not shown). Furthermore, the disk-shaped sample holder 14 can be rotated at an angular velocity ω about a rotation axis perpendicular to the disk plane by a rotation mechanism such as a motor (not shown). The rotation axis perpendicular to the disk plane is also the central axis of the cylindrical casing 12.

A reactive gas as a raw material fluid 18 for performing epitaxial growth on the substrate 16 is supplied from above to below the substrate 16 by a gas supply mechanism (not shown) along the direction of the central axis. . Here, a mixed gas of SiHCl ₃ + H ₂ can be used as the reaction gas.

  The surface treatment simulation apparatus 20 includes a CPU 30 that executes simulation calculation processing, an input unit 32 that inputs parameters for simulation, an output unit 34 that outputs simulation results, and a raw material fluid using a pump effect model. And a storage unit 38 for storing a model calculation program 36 for calculating 18 speed distributions, and these elements are connected to each other via an internal bus. Such a surface treatment simulation apparatus 20 can be configured by a computer suitable for numerical calculation.

  In addition, by providing the communication control unit 40 in the internal bus, a configuration in which the CPU 30 and the vertical rotary surface treatment apparatus 10 are connected by a communication line or the like can be employed. In that case, the CPU 30 acquires apparatus parameters, raw material fluid parameters, and the like of the vertical rotary surface treatment apparatus 10 via the communication control unit 40, and the calculation results such as the optimum flow rate setting value of the CPU 30 are obtained as the vertical rotary surface. It can be transmitted to the processing device 10. That is, the basic configuration of the surface treatment simulation device 20 can be used as the surface treatment device controller 21 of the vertical rotary surface treatment device 10.

  The storage unit 38 stores a model calculation program 36 for calculating the velocity distribution of the raw material fluid 18 using the pump effect model as described above. This model calculation program 36 is the basic described with reference to FIGS. 1 and 2. The model has been improved to fit the vertical rotary surface treatment apparatus 10.

  That is, the basic model in FIGS. 1 and 2 assumes an isothermal flow, but the vertical rotary surface treatment apparatus 10 heats the substrate 16 to a high temperature to perform uniform crystal growth. Therefore, in consideration of the temperature distribution in the boundary layer due to the substrate 16 being heated, a model calculation program 36 based on an improved model obtained by extending the basic model of FIGS. 1 and 2 is used as a flow of non-isothermal conditions.

Specifically, a model calculation program is stored that uses simultaneous equations (9) obtained by expanding Expression (1) and uses Expression (10) instead of Expression (2) as a boundary condition.

  Here, the velocities u, v, w and pressure p in the radial direction, the circumferential direction, and the axial direction are made dimensionless by the dimensionless distance ζ in the equation (5), and the temperature T is made dimensionless by Φ.

Further, λ is a thermal conductivity, c is a heat capacity, f is a ratio of a value at a specific local position of the raw material fluid 18 with respect to a value at the time of inflow of the raw material fluid 18, and fρ is a local value at the time of inflow. density ratio, f [lambda] denotes thermal conductivity ratio of input time and local, f _c is the heat capacity ratio of the input time and local, respectively. Further, the P _r in Prandtl number, the specific heat at constant pressure as c _P, is an amount represented by _{P r = ν / {λ /} (ρ × c P)}. The subscript ∞ indicates the inflow state of the raw material fluid 18, and the subscript w indicates the state on the surface of the substrate 16 which is a silicon wafer.

  As described above, the model calculation program 36 is based on the improved model extended from the basic model shown in FIGS. 1 and 2 to show the local characteristics of the non-isothermal flow in consideration of the temperature distribution. It is a program that can ask for.

  Note that F, G, and H calculated based on the model calculation program 36 basically exhibit the same characteristics as those described in FIG. That is, H indicating the axial velocity w of the fluid due to the pump effect becomes smaller as the distance z along the axial direction approaches the substrate 16 and becomes zero on the surface of the substrate 16. Further, F indicating the radial velocity u of the fluid due to the pump effect is zero on the surface of the substrate 16, but gradually increases as the distance z along the axial direction increases away from the substrate 16, and again when the distance from the substrate 16 further increases. It has a velocity distribution with a maximum velocity u (max) that returns to zero.

  Returning to FIG. 3, the CPU 30 applies the obtained surface treatment parameter to the model calculation program 36 by applying the obtained parameter acquisition processing unit 42 for inputting the surface treatment parameter, and the raw material fluid 18 for the heated substrate 16. Is generated on the heated substrate 16 on the basis of the model calculation processing unit 44 for calculating the velocity distribution and the calculation data of the axial velocity distribution of the raw material fluid 18 with respect to the heated substrate 16 and the apparatus parameters. Based on the optimum flow rate calculation processing unit 46 for calculating the optimum flow rate of the raw material fluid for the uniformity of the surface treatment, the calculation data of the radial velocity distribution of the raw material fluid 18 with respect to the substrate 16 being heated, and the apparatus parameters, A flow rate correction processing unit 48 for correcting the optimal flow rate is included.

  These functions can be realized by executing software, and specifically, can be realized by executing a surface treatment simulation program. If necessary, some of these functions may be realized by hardware.

  The operation of this configuration, particularly each function of the CPU 30, will be described in detail below with reference to FIGS. FIG. 4 is a flowchart showing a procedure for setting an optimum flow rate for the vertical rotary surface treatment apparatus 10. 5 to 9 are diagrams for explaining the contents of the procedure corresponding to FIG. FIG. 10 to FIG. 12 are diagrams for explaining the flow when the flow rate setting is appropriate and when it is inappropriate. FIG. 13 is a diagram for explaining the relationship between the uniformity of the crystal growth process as the surface treatment when the flow rate setting is appropriate and when it is inappropriate.

  FIG. 4 is a flowchart showing a procedure for setting the optimum flow rate as described above. After starting up and initializing the surface processing simulation program, first, the surface processing parameters are input from the input unit 32 and acquired (S10). This step is executed by the function of the parameter acquisition processing unit 42 of the CPU 30.

The surface treatment parameters include device parameters relating to the shape of the surface treatment device and raw material fluid parameters relating to the characteristics of the raw material fluid 18. The former is a parameter relating to the shape, size, and the like of the vertical rotary surface treatment apparatus 10. In particular, the inlet and outlet through which the raw material fluid 18 flows include those relating to the shape, size, etc. of the portion that affects the axial velocity distribution and the radial velocity distribution of the pump effect. The latter is a characteristic parameter of a mixed gas of SiHCl ₃ + H ₂ that is the raw material fluid 18 and includes μ, ρ, ν, λ, c _{P and the} like. In addition, temperature T, angular velocity ω, and the like are acquired as operation parameters.

  As described with reference to FIG. 3, when the surface treatment simulation device 20 or the surface treatment device controller 21 is connected to the vertical rotary surface treatment device 10 via the communication control unit 40, these surface treatments are performed. The parameters can be acquired in real time as the surface treatment of the vertical rotary surface treatment apparatus 10 progresses.

  Next, the model calculation program 36 stored in the storage unit 38 is read. Then, the pump effect model is calculated by applying the surface treatment parameter acquired in S12 to the model calculation program 36 (S12). This step is executed by the function of the model calculation processing unit 44 of the CPU 30. Specifically, equation (9), which is a five-way simultaneous equation, is solved under the boundary condition of equation (10), and the velocity distribution as described in FIG. 2 is calculated.

Incidentally, fρ, fλ, f _c, etc. can be set in advance prior experiment or the value of such literature references. For the parameters with the suffix ∞, values at the inlet sufficiently away from the substrate 16 are used.

  When the velocity distribution around the substrate 16 heated for the raw material fluid 18 is obtained based on the pump effect model in this way, the pump effect flow rate is calculated based on this (S46). This step is calculated by the function of the optimum flow rate calculation processing unit 46 of the CPU 30.

  Here, in the H characteristic calculated as the characteristic similar to FIG. 2, a value with dimensionless distance ζ = ∞, that is, z = ∞ is obtained, and this is calculated as the axial velocity w (∞). The w (∞) calculated in this way corresponds to the velocity at the inlet when the raw material fluid 18 is flowed at a thickness of δ according to the theoretical calculation of the pump effect model.

  By multiplying this axial velocity z (∞) by the area A of the surface perpendicular to the flow path, the flow rate at which δ is formed as the pump effect of the theoretical calculation is obtained. This flow rate is an optimum flow rate when attention is paid to the area of the surface perpendicular to the flow path, and corresponds to the optimum flow rate before correction by the outlet shape described later. 5 and 6, if the area A of the surface perpendicular to the flow path is set according to the flow path shape of the inlet of the vertical rotary surface treatment apparatus 10, the δ according to the theoretical pump effect can be obtained. An example of whether the flow rate is formed will be shown.

In FIGS. 5 and 6, the sample holder 14, the substrate 16, and the inlet of the raw fluid 18 are all circular, the diameter of the sample holder 14 is D, and the inlet of the raw fluid 18 is d. This is an example of the explanation, and the size relationship between the surface area A ₁ where the surface treatment is performed and the cross-sectional area A _{2 of the} inlet of the raw material fluid 18 is important. Regardless, the description will be made using the relationship between A ₁ and A ₂ .

Figure 5 shows a case of a vertical flow path configuration called closed, as compared to the surface area A ₁ = πD ^2/4 of the sample holding stage 14, the cross-sectional area of the inlet of the raw material fluid A ^₂ = πd _2/4 is This is the case. At this time, the flow rate Q = A ₁ × w (∞) obtained by multiplying the axial speed z (∞) by A ₁ is set as the optimum supply flow rate of the raw material fluid. If the flow rate obtained by multiplying the axial velocity z (∞) by A ₂ is set, the velocity distribution according to the pump effect cannot be obtained on the surface of the substrate 16.

6, in the case of a vertical flow path configuration called the open, in comparison to the surface area A ₁ = πD ^2/4 of the sample holding stage 14, the cross-sectional area of the inlet of the raw material fluid A ^₂ = πd _2/4 is This is the case. At this time, a flow rate Q = A ₂ × w (∞) obtained by multiplying the axial speed z (∞) by A ₂ is set as an optimum supply flow rate of the raw material fluid. If the flow rate obtained by multiplying the axial velocity z (∞) by A ₁ is set, the velocity distribution according to the pump effect cannot be obtained on the surface of the substrate 16.

Thus, when focusing on the area of the surface perpendicular to the flow path, the optimum flow rate for realizing the flow according to the pump effect is the surface area A of the heated substrate 16 at the axial velocity w (∞). ₁ or Q = A × w (∞), which is a value obtained by multiplying the larger area A of the cross-sectional area A ₂ of the inlet of the raw material fluid in the surface treatment apparatus, is necessary.

FIG. 7 is a diagram showing the state of Q = A × w (∞) calculated based on the pump effect model for the flow under non-isothermal conditions, with the temperature and angular velocity being changed. The horizontal axis is the temperature T _{w on the} wafer surface, the vertical axis is Q = A × w (∞) expressed in arbitrary units, and the parameter is the number of revolutions per minute corresponding to the angular velocity ω. As shown here, the optimum flow rate focusing on the area of the surface perpendicular to the flow path increases as the angular velocity ω increases, and decreases as the wafer surface temperature increases.

  Returning to FIG. 4 again, when the optimal flow rate is calculated by paying attention to the area of the surface perpendicular to the flow path in S14, the optimal flow rate calculation with the flow path shape corrected is performed (S16). This step is executed by the function of the flow rate correction processing unit 48 of the CPU 30. Actually, the increase / decrease correction of the optimum flow rate calculated in S14 is performed according to the flow path shape on the outflow side of the raw material fluid.

  FIG. 8 is a diagram illustrating an example of the shape of the flow path on the outflow side in the sealed casing 12. In the vertical rotary surface treatment apparatus 10, the raw material fluid 18 is supplied from above the rotating substrate 16 toward the surface thereof, flows along the surface of the substrate 16 by centrifugal force, and radially extends from the outer peripheral end portion. Flows out as an outflow fluid 19. Therefore, as the flow path shape of the outlet of the vertical rotary surface treatment apparatus 10, as shown in FIG. 8, a gap is opened from the surface of the sample holder 14 along the axial direction by h, and the sample holder 14 The one having a gap of S (edge) along the radial direction from the outer peripheral end is used.

  Here, h and S (edge) are based on the sample holder 14, but as described in relation to FIG. 5 and FIG. 6, the diameter of the substrate 16 to exhibit the pump effect and the sample holder 14. There is no large difference in diameter, and the thickness of the substrate 16 is almost negligible compared with h. Therefore, the sample holding table 14 is a shape unique to the vertical rotary surface treatment apparatus 10 instead of the shape of the substrate 16. This is represented by the shape of Therefore, h and S (edge) may be the distance from the surface of the substrate 16 and the distance from the outer peripheral edge of the substrate 16, respectively.

  If h and S (edge) are inappropriate, the radial velocity distribution calculated by the pump effect model may be affected. FIG. 9 is a diagram showing the distribution in the axial direction of u, which is the radial velocity at the outer peripheral edge of the sample holder 14 or the substrate 16. As described with reference to FIG. 2, the distribution characteristic of F corresponding to the radial velocity u is zero on the surface of the substrate 16, but gradually increases as z moves away from the substrate 16, and further from the substrate 16. It has a maximum speed u (max) that returns to zero again when the distance increases.

Therefore, if an appropriate threshold speed is set, the flow exceeding the threshold speed will have a certain width in the axial direction. In other words, the flow exceeding the threshold velocity in the range of the height width along the axial direction flows out from the outer peripheral end of the substrate 16 in the radial direction to become the outflow fluid 19. The maximum velocity of the outflow fluid 19 is u (max). In FIG. 9, the range of the height width along the axial direction of the flow flowing out in the radial direction is shown as h ₀ .

8 and 9, it can be seen that the flow path shape on the outflow side of the vertical rotary surface treatment apparatus 10 is preferably as follows. That is, h is preferably the same as h ₀ . If h is larger than h ₀ , the cross-sectional area of the outlet is excessive, and the outflow fluid 19 may flow backward. Therefore, in such a case, it is preferable to increase the flow rate by correcting the optimal flow rate calculated in S14 so that backflow can be prevented.

  Further, S (edge) is a distance that the outflow fluid 19 that flows out in the radial direction hits the inner wall of the housing portion 12, and is preferably a dimension according to u (max). That is, it is preferable to increase S (edge) when u (max) is large. If S (edge) is too small compared to the size of u (max) and the spilled fluid 19 strikes the inner wall of the housing 12, the spilled fluid 19 may flow backward. Therefore, in such a case, it is preferable to increase the flow rate by correcting the optimal flow rate calculated in S14 so that backflow can be prevented. The relationship between u (max) and S (edge) that causes backflow can be obtained by separately performing a flow field simulation in advance.

  In this way, the optimum flow rate Q = Aw (∞) calculated by paying attention to the area of the surface perpendicular to the flow path in S14 is corrected according to the flow path shape on the outflow side of the vertical rotary surface treatment apparatus 10. Is done. The corrected result takes into consideration the area of the surface perpendicular to the flow path and the shape of the outlet, and the flow rate matches the pump effect model. Therefore, this is set as the corrected optimal flow rate in the actual surface treatment. (S18).

  FIGS. 10 to 12 are views showing a state in which the flow field of the raw material fluid 18 around the outer peripheral edge and the outlet of the substrate 16 of the vertical rotary surface treatment apparatus 10 is analyzed using a separately constructed flow simulation program. is there. FIG. 10 shows a case where the set flow rate is less than the optimum condition, FIG. 11 shows a case where the set flow rate is the optimum condition, and FIG. 12 shows a case where the set flow rate is excessive compared to the optimum condition. Here, the optimum condition is a condition in which the optimum flow rate is corrected for the area of the surface perpendicular to the flow path and the outlet shape in accordance with each procedure described in FIG.

  As shown in FIG. 10, when the set flow rate is 2/3 less than the optimum condition, the outflow fluid 19 once flowing out from the outer peripheral edge of the substrate 16 flows backward, and the flow is disturbed at the outer peripheral portion of the substrate 16. Thus, it can be seen that the flow does not match the pump effect. If the set flow rate is increased from this state to obtain the optimum condition, the flow on the surface of the substrate 16 is made uniform as shown in FIG.

  When the set flow rate is further increased to 1.5 times the optimum condition, as shown in FIG. 12, an excess portion of the effluent fluid 19 is concentrated near the inlet of the effluent portion, resulting in a flow clogging phenomenon. The flow is partially uneven at the outer periphery of 16, and the flow does not match the pump effect.

  FIG. 13 is a diagram showing the result of analyzing the distribution of the crystal growth rate on the wafer by actually performing the epitaxial growth process in the vertical rotary surface treatment apparatus 10. Here, the case where the set flow rate is 50% and 75% with respect to the optimum condition is shown as a comparative example. As shown in FIG. 13, when the set flow rate is less than the optimum condition, the crystal growth rate is reduced on the wafer outer peripheral side. As described with reference to FIG. 10, the backflow of the outflow fluid 19 occurs, and the already reacted gas is returned to the outer peripheral side of the wafer without being discharged. As a result, it should be supplied for crystal growth on the outer peripheral side of the wafer. It is considered that the concentration of the raw material fluid 18 is lowered.

  FIG. 14 is a diagram illustrating the configuration of the vertical rotary surface treatment system 100. The vertical rotary surface treatment system 100 includes a vertical rotary surface treatment apparatus 10 and a surface treatment apparatus controller 21. Here, the vertical rotary surface treatment apparatus 10 supplies a raw material fluid 18 for surface treatment to the rotating substrate 16 in a substantially vertical direction, and then causes the fluid to flow along the surface of the substrate 16 so as to surface the substrate 16. The processing is performed. Specifically, the vertical rotary surface treatment apparatus 10 is an epitaxial apparatus that epitaxially grows a semiconductor layer on a substrate such as a semiconductor wafer or an insulator wafer.

  The vertical rotary surface treatment apparatus 10 is an apparatus having a configuration in which a disk-shaped sample holding base 14 is provided inside a casing 12 that forms a cylindrical peripheral wall. FIG. 14 shows a substrate 16 that is not a component of the vertical rotary surface treatment apparatus 10 but is a target of silicon single crystal epitaxial growth treatment as surface treatment. The substrate 16 can be a silicon wafer.

  The casing 12 supplies the source gas, which is the source fluid 18 for surface treatment, to the substrate 16 while isolating the substrate 16 which is the sample on the sample holder 14 from the outside, and the outflow fluid which is the used fluid It is the reaction container which has the function to guide 19 outside.

  A cylindrical portion 102 provided on the upper side of the sample holding base 14 in the casing 12 is a raw material fluid supply flow path section that supplies the raw material fluid 18 to the substrate 16 that is a sample on the sample holding base 14.

  A flow channel portion that is provided on the side of the sample holder 14 in the housing portion 12 and is widened when viewed from the cylindrical portion 102 is an outflow flow channel portion 104. The outflow channel section 104 performs surface treatment on the substrate 16 while the raw material fluid 18 supplied as a vertical flow from above the sample holding base 14 toward the sample substrate 16 flows along the surface of the substrate 16. In addition, the flow path has a function of flowing out through the outlet on the side of the sample holder 14 as the outflow fluid 19 that is a used fluid. Details of the shape and the like of the outflow passage 104 will be described later.

The supply unit 110 connected to the cylindrical portion 102 of the casing unit 12 has a function of supplying a reaction gas as a raw material fluid 18 for silicon single crystal epitaxial growth processing at a constant pressure and a constant flow rate. Device. As the reaction gas, a mixed gas of SiHCl ₃ + H ₂ can be used.

  The discharge unit 112 connected to the outflow channel unit 104 of the casing unit 12 has a function of discharging the outflow fluid 19 guided from the outflow channel unit 104 to the outside by performing an appropriate discharge detoxification process. It is. The discharge unit 112 can include a discharge pump or the like for easily guiding the used gas to the outside. As the discharge detoxification process, a dilution process can be used, and a removal process that removes harmful components contained in the effluent fluid 19 by a precipitation reaction or the like can be used.

  The sample holder 14 is a rotating body that has a function of holding the substrate 16 as a sample to be surface-treated and rotating it while heating it. The sample holder 16 has a flat upper surface, and the substrate 16 is disposed on the flat surface. Alternatively, a recess for positioning the substrate 16 may be provided on the upper surface of the sample holder 16 and the substrate 16 may be disposed in the recess. The sample holding base 14 is a cylindrical member with a ceiling having a concave portion on the lower side, and has a sample holding mechanism for firmly holding the substrate 16 on the upper surface side, and a heater 106 is placed in the lower concave portion. Stored. As the sample holding mechanism, a mechanism provided with a recess according to the outer shape of the wafer can be used. In addition, a mechanism for mechanically fixing the outer periphery of the wafer, a mechanism for sucking and fixing the wafer by vacuum, and the like can be used. it can. The sample holding function rotates together with the sample holding table 14, but the heater 106 does not rotate.

  The rotating unit 114 is a rotating mechanism having a function of rotating the sample holder 14 at a predetermined angular velocity ω around the rotation center axis. The rotation center axis is perpendicular to the surface of the sample holder 14 and can be a center axis of a cylindrical shape with a ceiling. In addition, it is preferable that the rotation center axis be as coaxial as possible with the center axis of the cylindrical portion 102 of the housing portion 12. As the rotating unit 114, a power transmission mechanism for connecting an electric motor and a cylindrical outer periphery with a ceiling of the sample holder 14 and the electric motor can be used. As the power transmission mechanism, a gear mechanism, a belt mechanism, or the like can be used.

  The heating unit 116 is a heating control device for controlling the energization of the heater 106 housed and held in the sample holding table 14 to set the substrate 16 to a predetermined reaction temperature. The heating control can be performed based on data from a temperature sensor that detects the temperature of the heater 106.

  The protective ring 108 provided on the outer periphery of the sample holding table 14 is an outer arrangement member having a function of protecting the outer periphery when the sample holding table 14 rotates.

  The surface treatment device control device 21 is a device that mainly controls the content of the operation of the vertical rotary surface treatment device 10 already described in FIG. Specifically, the operation of the gas supply device in the supply unit 110 is controlled to set the flow rate and the like, the operation of the discharge processing device in the discharge unit 112 is controlled to discharge the outflow fluid 19, and the rotation mechanism in the rotation unit 114. And the sample holding table 14 is rotated at an angular velocity ω, and the sample holding table is maintained at a predetermined temperature by energization control of the heater 106 in the heating unit 116.

  As described with reference to FIG. 3, the surface treatment apparatus control device 21 outputs the CPU 30 that performs arithmetic processing, the input unit 32 that inputs parameters for the arithmetic processing, and the result of the arithmetic processing. Model calculation program for calculating the velocity distribution of the raw material fluid 18 using the pump effect model, the output control unit 34, the communication controller 40 for connecting the vertical rotary surface treatment apparatus 10 to the network or an appropriate communication line, and the like. And a storage unit 38 for storing 36. Here, the flow rate-variation relationship 56, the flow rate-reverse flow penetration length relationship 58, and the variation-reverse flow penetration length relationship 59 of the storage unit 38 are files added to the contents described with reference to FIG. These elements are connected to each other by an internal bus. The surface treatment device control device 21 can be configured by a computer suitable for numerical calculation.

  Then, as described with reference to FIG. 3, the CPU 30 is heated by applying the parameter acquisition processing unit 42 for inputting the surface processing parameters and the acquired surface processing parameters to the model calculation program 36. The model calculation processing unit 44 for calculating the velocity distribution of the raw material fluid 18 with respect to the substrate 16 being heated, the calculation data of the axial velocity distribution of the raw material fluid 18 with respect to the substrate 16 being heated, and the apparatus parameters are heated. The optimum flow rate calculation processing unit 46 for calculating the optimum flow rate of the raw material fluid for the uniformity of the surface treatment generated on the substrate 16 and the calculation data of the radial velocity distribution of the raw material fluid 18 with respect to the heated substrate 16 And a flow rate correction processing unit 48 that corrects the optimal flow rate based on the apparatus parameters. Also included is a productivity flow rate setting processing unit 54 that is less than the optimum flow rate and is acceptable from the viewpoint of productivity while taking into account the influence of backflow and the like. This productivity flow rate setting processing unit 54 is based on the flow rate-variation relationship 56, the flow rate-reverse flow penetration length relationship 58, and the variation-reverse flow penetration length relationship 59 of the storage unit 38, and the productivity flow rate allowable from the viewpoint of productivity. This function has a setting function and is added to the contents described in relation to FIG.

  These functions can be realized by executing software, and specifically, can be realized by executing a surface treatment simulation program. If necessary, some of these functions may be realized by hardware.

  As described with reference to FIG. 3 and the like, the optimal flow rate is set by the functions of the parameter acquisition processing unit 42, the model calculation processing unit 44, the optimal flow rate calculation processing unit 46, and the flow rate correction processing unit 48 of the surface treatment device controller 21. Alternatively, flow rate correction processing can be performed. With these functions, as described with reference to FIG. 13, the vertical rotary surface treatment apparatus 10 can perform surface treatment with almost no variation. In addition to these functions, the control device 21 of the surface treatment system 10 in FIG. 14 can set a productivity flow rate that is acceptable from the viewpoint of productivity while taking into consideration the influence of backflow and the like even if the flow rate is less than the optimum flow rate. It has a function. Below, the content is demonstrated in detail.

  If the set flow rate is less than the optimum flow rate or the flow rate after the flow rate is corrected from the optimum flow rate, backflow or the like occurs. As a result, the crystal growth rate in the wafer varies. This is schematically shown in FIGS. 15 and 16. FIG. 15 shows the flow when the flow rate is set to the optimum flow rate, and the flow is smooth over the entire area of the substrate 16. FIG. 16 shows a state where the flow rate is set lower than the optimum flow rate, and a reverse flow 60 of the flow occurs at the end of the substrate 16. As a result, the surface treatment varies at the edge of the substrate 16.

It is expected that the variation in surface treatment on the substrate 16 increases as the range in which the backflow 60 occurs in the substrate 16 is wider. Therefore, in order to evaluate the degree of the backflow 60 generated in the substrate 16, the backflow penetration length h _r ^* is defined as follows. That is, the backflow penetration length h _r ^* = (h _r −s) / (d _w / 2).

Here, h _r indicates the position where the X direction position of the outermost stream line is the smallest among the stream lines that are not the backflow 60. As shown in FIG. 16, from the inner wall of the cylindrical portion 102, It is the length measured toward the central axis. In other words, the distance from the inner wall of the position the cylindrical portion 10 of the X-direction position of the flow lines flowing from the outflow portion ends in the cylindrical portion 102 of the surface treatment apparatus 10 is minimized is h _r. As shown in FIG. 16, the X direction is a direction from the central axis of the surface treatment apparatus 10 toward the outer peripheral side, and corresponds to a so-called radial direction. In the surface treatment apparatus 10, the streamline when the raw material fluid 18 supplied from the cylindrical portion 102 flows out from the outflow passage portion 104 toward the discharge portion 112 as the outflow fluid 19 is the minimum position in the X direction of the backflow 60. At a certain position, that is, outside the inner edge of the backflow 60. Therefore, in this streamline, the position where the X direction position of the outermost streamline is minimum can be treated as indicating the inner edge of the backflow 60. Then, it is possible by h _r, measured towards the central axis position of the inner edge of the reverse flow 60 from the inner wall of the cylindrical portion 102, to evaluate the size range of the backflow 60 to the diameter d of the cylindrical portion 102.

In order to evaluate the penetration length of the backflow 60 in the substrate 16, it is preferable to measure how much the backflow 60 penetrates from the outer peripheral edge of the substrate 16. s is the difference between the radius d / 2 of the cylindrical portion 102 and the radius d _w / 2 of the substrate 16. Therefore, (h _r -s) shows the range in which reverse flow 60 entering from the outer peripheral edge of the substrate 16. The backflow penetration length h _d ^* is the dimension of this (h _r −s) normalized by the radius d _w / 2 of the substrate 16 and is a dimensionless number. For example, h _r ^* = 0.1 indicates that the backflow 60 has entered the range from the outer periphery of the substrate 16 to a portion corresponding to 10% of the radius.

The backflow penetration length h _r ^* can be obtained by simulation calculation if apparatus parameters relating to the shape of the surface treatment apparatus 10 and surface treatment parameters including raw material fluid parameters relating to characteristics of the raw material fluid are given. FIG. 17 shows an example of the relationship between the flow rate obtained by the simulation calculation and the backflow penetration length h _r ^* . The horizontal axis in FIG. 17 is the inflow flow rate Q that has flowed into the cylindrical portion 102 from the supply unit 110, and the flow rate Q ₀ is the optimal flow rate obtained by the function of the optimal flow rate calculation processing unit 46. As shown in FIG. 17, at the optimum flow rate Q ₀ , the reverse flow penetration length h _r ^* is 0, but even if the flow rate is slightly smaller than the optimal flow rate Q _{0, the} reverse flow penetration length h _r ^* increases rapidly. after then it became almost constant value, further backflow penetration depth h _r ^* increases according to the flow rate increases.

As described in FIG. 13, in accordance with the flow rate is reduced from the optimum flow rate Q _0, the variation of the surface treatment increases. In the case of FIG. 13, the crystal growth rate varies and the grown film thickness varies. The relationship between the flow rate and the surface treatment variation can be obtained by an experiment using the surface treatment apparatus 10 or the like. Figure 17 is an example of which the flow rate was determined by simulation calculation - are shown in association with reflux penetration depth h _r ^* relationship. As shown in FIG. 17, as the inflow flow rate Q decreases, the film thickness variation Δt, which is the surface treatment variation, increases.

Meanwhile, if the variation of the surface treatment is acceptable to some extent, so that it is possible to reduce the flow rate from the optimum flow rate Q _0. For example, in FIG. 13, if, when the variation in the crystal growth rate is within 5% is that there is no practical problem, the flow rate can be reduced by 25% than the optimum flow rate Q _0. The extent to which the surface treatment variation can be actually tolerated depends on the surface treatment specifications, but considering the tolerance of the variation, the flow rate can be reduced from the optimum flow rate Q ₀ and the productivity can be improved. It becomes possible.

  Returning to FIG. 14, the CPU 30 of the surface treatment device control device 21 includes a productivity flow rate setting processing unit 54. As described above, the productivity flow rate setting processing unit 54 is allowed from the viewpoint of productivity based on the flow rate-variation relationship 56, the flow rate-reverse flow penetration length relationship 58, and the variation-reverse flow penetration length relationship 59 of the storage unit 38. It has a function to set productivity flow rate.

As described above, the storage unit 38 stores the flow rate-variation relationship 56, the flow rate-reverse flow penetration length relationship 58, and the variation-reverse flow penetration length relationship 59 for the productivity flow rate setting processing unit 54. The flow rate-variation relationship 56 is flow rate-variation relationship data that is a relationship between an arbitrary flow rate less than the optimum flow rate Q ₀ and the variation amount with respect to the uniformity of the surface treatment, as described in connection with FIG. It can be obtained in advance by experiments or the like. Further, as described in relation to FIG. 17, the flow rate-reverse flow penetration length relationship 58 is an arbitrary flow rate smaller than the optimum flow rate Q ₀ and a reverse flow penetration length indicating the degree of the reverse flow generated on the substrate 16. It is data of the relationship between the flow rate and the reverse flow penetration length, which is a relationship, and can be obtained in advance by simulation calculation.

Further, the variation-reverse flow penetration length relationship 59 is relationship data obtained using the flow rate-variation relationship 56 and the flow rate-reverse flow penetration length relationship 58. That is, as shown in FIG. 17, when the film thickness variation Δt is given, the corresponding backflow penetration length hr ^* is obtained through the flow rate Q corresponding thereto. The relationship between the film thickness variation Δt and the backflow penetration length h _r ^* thus obtained is the dispersion-backflow penetration length relationship 59. FIG. 18 shows a graph of the variation-backflow penetration length relationship calculated based on the data of FIG.

  In this way, when the flow rate-variation relationship 56, the flow rate-reverse flow penetration length relationship 58, and the variation-reverse flow penetration length relationship 59 are obtained in advance, these are stored in the storage unit 38 as described above.

17 and 18, it can be explained that the surface treatment can be performed at a flow rate less than the optimum flow rate Q ₀ while maintaining the film thickness variation Δt within an allowable range from the viewpoint of productivity. For example, in FIG. 17, the thickness variation Delta] t, when the threshold variation and (Delta] t) _th a thickness variation acceptable from the viewpoint of productivity, the flow rate - the variation relationship, corresponding to the threshold variation (Delta] t) _th flow Is required. When this flow rate is a threshold flow rate Q _th , if the inflow flow rate Q is a value from Q _th to Q _{0 and} up to Q ₀ , the film thickness variation (Δt) is equal to or less than the threshold value variation that is allowable film thickness variation from the viewpoint of productivity. Can be. Looking at this in reverse flow penetration depth h _r ^*, backflow penetration depth h _r ^* a threshold backflow penetration depth corresponding to the threshold flow rate Q _th (h _r ^*) as _th, backflow penetration depth h _r ^* is the threshold backflow penetration depth ( If h _r ^* ) _th or less, the film thickness variation (Δt) can be made equal to or less than the threshold value variation, which is an allowable film thickness variation from the viewpoint of productivity. That is, when the film thickness variation does not interfere with the practical specification, the inflow flow rate Q can be reduced from the optimum flow rate Q ₀ to the threshold flow rate Q _th by setting the threshold flow rate Q _th as the productivity flow rate Q ₁ . Productivity is improved and costs can be reduced.

  FIG. 19 is a flowchart showing a procedure for setting the productivity flow rate. Among these procedures, as described above, S20, S22, and S24 give the surface treatment parameters including the apparatus parameters related to the shape of the surface treatment apparatus 10 and the raw material fluid parameters related to the characteristics of the raw material fluid. This is a procedure for performing an experiment with the apparatus 10 or performing a simulation calculation and storing the result in the storage unit 38. S <b> 26, S <b> 30, S <b> 32 and S <b> 34 correspond to procedures executed by the function of the productivity flow rate setting processing unit 54 of the control device 21 using the results stored in the storage unit 38.

  First, a relationship between flow rate and film thickness variation is derived by experiment (S20). The film thickness variation is an example of the surface treatment variation, and can be appropriately set according to the purpose of the surface treatment system. An example of the flow rate-film thickness variation relationship is the relationship diagram described with reference to FIG. The derived flow rate-film thickness variation relationship is stored as the flow rate-variation relationship 56 in the storage unit 38 in the form of a map, a mathematical formula, a loop-up table, etc. with the apparatus parameters and the raw material fluid parameters.

In parallel with S20 or before and after S20, the relationship between the flow rate and the backflow penetration length is derived by simulation calculation (S22). As the backflow penetration length, h _r ^* defined in relation to FIG. 17 can be used. However, since the backflow penetration length h _r ^* = (h _r −s) / (d _w / 2) described in FIG. 17 is an example of a value indicating the degree of back flow generated on the substrate 16, You may define the backflow penetration length of the contents. For example, (h _r −s) may be defined as the backflow penetration length without using a dimensionless value. An example of the relationship between the flow rate and the backflow penetration length is the relationship diagram as described above with reference to FIG. The derived flow rate-reverse flow penetration length relationship 58 is stored in the storage unit 38 in the form of a map, a mathematical formula, a loop-up table, etc. with the apparatus parameter and the raw material fluid parameter.

  When the flow rate-variation relationship 56 data and the flow rate-reverse flow penetration length relationship 58 are obtained in this way, the variation-reverse flow penetration length is obtained from these data as described with reference to FIGS. The relationship 59 is derived (S24). The derived variation-backflow penetration length relationship 59 is stored in the storage unit 38 in the form of a map, a mathematical formula, a loop-up table, or the like.

Next, a threshold value variation (Δt) _th that is an allowable film thickness variation from the viewpoint of productivity is determined, a variation-backflow penetration length relationship 59 is read from the storage unit 38, and a threshold value backflow corresponding to the threshold value variation (Δt) _th is obtained. penetration depth (h _r ^*) _th to calculate the (S26). The threshold variation (Δt) _th is determined in consideration of productivity, that is, performance expected for surface treatment, economical yield, and the like. For example, a yield of about 90% is economically required, and the film thickness variation corresponding to the yield is ± 5%. If the film thickness variation is satisfied, the performance expected for the surface treatment is satisfied. When the above yield is obtained and the performance is not satisfactory with the corresponding film thickness variation, the threshold variation (Δt) _th is set to ± 5%. Then, for example, by using a relationship diagram shown in Figure 18, the threshold reflux penetration depth (h _r ^*) _th is calculated.

Next, the control device 21 calculates an optimum flow rate Q ₀ under new operating conditions by the function of the optimum flow rate calculation processing unit 46 (S30). Further, the flow rate correction is performed by the function of the flow rate correction processing unit 48 as necessary. The contents of these processing procedures have been described with reference to FIG.

Since the backflow penetration length under the condition of the optimum flow rate Q ₀ is zero, it is shorter than the threshold backflow penetration length. Therefore, it can be seen that the flow rate can be reduced under the threshold backflow penetration length that can be determined from the viewpoint of productivity. Therefore, the flow rate is set to an arbitrary value less than the optimum flow rate Q ₀ , and the backflow penetration length corresponding to the value is calculated by simulation (S 32). Then, the flow rate of backflow penetration length to be calculated is reduced to a threshold reflux penetration length is set as productivity rate Q ₁ (S34). The productivity flow rate Q ₁ set in this way is the same value as the threshold flow rate Q _th described in FIG. By such a procedure, it is possible to set a backflow penetration length that is acceptable from the viewpoint of productivity for the backflow 60 that does not occur under the optimum flow rate Q ₀ , and to reduce the flow rate until the backflow penetration length is reached. Become.

FIG. 20 is a diagram for explaining a flow rate range in which the productivity flow rate can be set. The relationship diagram shown in the upper part of FIG. 20 is a diagram showing the relationship between the film thickness variation Δt and the backflow penetration length h _r ^* with respect to the flow rate described in FIG. 17, and the horizontal axis is the flow rate. FIG. 20 shows the flow on the substrate 16 for each of the four flow rates. When the flow rate is set to the optimum flow rate Q ₀ , no backflow 60 is generated on the substrate 16. On the other hand, when the flow rate is less than the optimum flow rate Q ₀ , the backflow 60 is generated on the substrate 16. When the flow rate is smaller than the productivity flow rate Q ₁ , the backflow 60 considerably enters the substrate 16 and the film thickness variation Δt increases. When the flow rate is less than the optimum flow rate Q ₀ but smaller than the productivity flow rate Q ₁ , a reverse flow 60 is generated on the substrate 16, and the reverse flow penetration length is larger than the threshold reverse flow penetration length determined from the viewpoint of productivity. small. Therefore, if it is within this range, the generated backflow 60 can be tolerated from the viewpoint of productivity, and actual production may be performed at a productivity flow rate Q ₁ whose flow rate is smaller than the optimum flow rate Q ₀ .

If the four cases in FIG. 20 are (a), (b), (c), and (d), respectively, the raw material fluid flows out smoothly in the case of (a) where the flow rate is the optimum flow rate Q ₀ . When the flow rate is much smaller than the optimum flow rate Q ₀ (b), the backflow 60 reaches the substrate 16 and the supply of the raw material fluid on the outer peripheral portion of the substrate 16 becomes insufficient, thereby increasing the film thickness variation. . When the flow rate is less than the productivity flow rate, the allowable film thickness variation is exceeded.

On the other hand, the length in the longitudinal direction of the substrate 16 is generally smaller than the length in the longitudinal direction of the sample holder 14 and the inner diameter of the cylindrical portion 12 of the housing 12, so that the flow in the cylindrical portion 12 is reduced. The backflow 60 generated on the outer peripheral side does not affect the substrate 16 as it is. Even if the flow rate is small from the optimum flow rate Q ₀ , as long as the difference is not large, as shown in (c), the generation of the backflow 60 is small and does not reach the substrate 16, or it is shown in (d). As described above, even if the backflow 60 reaches the substrate 16, the influence on the film thickness variation is only within an allowable range from the viewpoint of productivity. Therefore, as shown in FIGS. 20C and 20D, if the flow rate is larger than the productivity flow rate Q ₁ , the film thickness variation can be allowed from the viewpoint of productivity, so that the flow rate is changed from the optimal flow rate Q ₀ to the productivity flow rate Q 1. Can be reduced to ₁ .

  In the above description, the case of crystal growth is described as the surface treatment, and the surface treatment variation is defined as the film thickness variation. However, another example of the surface treatment is an etching treatment. Even in the case of the surface treatment for thin film / crystal growth, a by-product due to the surface reaction may contain a component having an etching effect even if it is not an etching treatment. Thus, even when the component having the etching effect is the backflow 60, the threshold backflow penetration length can be allowed, so that the backflow 60 reaches the outer peripheral portion of the substrate 16 as shown in FIG. As a result, sticking between the substrate 16 and the sample holder 14 can be prevented or the sticking problem can be improved.

  In this way, it is possible to set a productivity flow rate that is more suitable for productivity by further development than the optimum flow rate setting. In some cases, one vertical rotary surface treatment apparatus 10 can selectively use high-quality surface treatment with little variation and productivity surface treatment with good productivity.

  A surface treatment simulation device, a control device for a surface treatment device, and a surface treatment system according to the present invention supply a raw material fluid such as an appropriate reaction gas onto a substrate, and a semiconductor layer, an insulating film, or a conductor layer on the substrate. Or the like, or the surface of the substrate is etched or cleaned, or a vertical rotary surface treatment for forming a coating material, analysis of the surface treatment, and control of the surface treatment apparatus.

  DESCRIPTION OF SYMBOLS 10 Vertical rotary surface treatment apparatus, 12 Case part, 14 Sample holding stand, 16 Substrate, 18 Raw material fluid, 19 Outflow fluid, 20 Surface treatment simulation apparatus, 21 Control apparatus for surface treatment apparatus, 30 CPU, 32 inputs Unit, 34 output unit, 36 model calculation program, 38 storage unit, 40 communication control unit, 42 parameter acquisition processing unit, 44 model calculation processing unit, 46 optimum flow rate calculation processing unit, 48 flow rate correction processing unit, 50 disc, 52 z-axis, 54 Productivity flow rate setting processing unit, 56 Flow rate-variation relationship data, 58 Flow rate-reverse flow penetration length relationship, 59 Variation value-reverse flow penetration length relationship, 60 Reverse flow, 100 Vertical rotary surface treatment system, 102 Cylindrical shape Part, 104 Outflow channel part, 106 Heater, 108 Protective ring, 110 Supply part, 112 Discharge part, 114 times Department, 116 heating unit.

Claims (9)

A simulation device for calculating an optimum gas condition in a vertical rotary surface treatment apparatus that supplies a surface treatment raw material fluid to a rotating substrate in a substantially vertical direction and performs surface treatment on the substrate,
An acquisition means for acquiring surface treatment parameters including apparatus parameters relating to the shape of the surface treatment apparatus and raw material fluid parameters relating to characteristics of the raw material fluid;
Using the pump effect model of the flow around the rotating disk in the fluid, the axial direction is a characteristic of the axial velocity of the raw material fluid with respect to the distance along the axial direction, with the direction perpendicular to the rotating disk surface as the axial direction. A storage unit for storing a model calculation program for calculating a velocity distribution;
Model calculation means for applying the surface treatment parameters acquired by the acquisition means to the model calculation program and calculating the axial velocity distribution of the raw material fluid with respect to the substrate;
An optimal flow rate calculation means for calculating an optimal flow rate of the raw material fluid for the uniformity of the surface treatment generated on the substrate, based on the calculation data of the axial velocity distribution of the raw material fluid with respect to the substrate and the apparatus parameters;
A surface treatment simulation apparatus comprising: In the surface treatment simulation apparatus according to claim 1,
The optimum flow rate calculation means is
For the axial velocity distribution of the raw material fluid with respect to the substrate, the axial velocity w (∞) calculated when the axial distance is infinite is the surface area A _{1 of} the substrate or the sectional area of the inlet of the raw material fluid in the surface treatment apparatus. A surface treatment simulation apparatus, wherein Q = A × w (∞), which is a value obtained by multiplying the larger area A of A ₂ , is calculated as an optimum flow rate. In the surface treatment simulation apparatus according to claim 2,
The storage unit
In addition to calculating the axial velocity distribution of the raw material fluid, the radial velocity distribution, which is a characteristic of the radial direction velocity of the raw material fluid with respect to the distance along the axial direction, is also calculated with the radial direction of the rotating disk as the radial direction Store the model calculation program
Model calculation means
In addition to calculating the axial velocity distribution of the raw material fluid with respect to the substrate, further calculating the radial velocity distribution of the raw material fluid with respect to the substrate,
further,
A surface treatment simulation apparatus comprising flow rate correction means for correcting an optimum flow rate based on calculation data of a radial velocity distribution of a raw material fluid with respect to a substrate and apparatus parameters. In the surface treatment simulation apparatus according to claim 3,
The flow rate correction means
Regarding the radial velocity distribution of the raw material fluid with respect to the substrate, the radial velocity increases as the distance along the axial direction increases, decreases to the maximum velocity again, and is calculated as the axial distance when the velocity falls below a predetermined threshold velocity. The height in the radial direction is the outflow height h _0, and the opening height along the axial direction from the surface of the substrate at the outlet of the raw material fluid in the surface treatment apparatus is h, and the optimum flow rate according to h with respect to h ₀ A surface treatment simulation apparatus characterized by correcting the above. In the surface treatment simulation apparatus according to claim 3,
The flow rate correction means
Regarding the radial velocity distribution of the raw material fluid with respect to the substrate, the radial velocity increases as the distance along the axial direction is increased, and the maximum maximum velocity is u (max). A surface treatment simulation apparatus that corrects the optimum flow rate according to S (edge) with respect to u (max), where S (edge) is the distance that the raw material fluid strikes along the radial direction of the substrate from the outer peripheral edge. . A control device for a surface treatment apparatus that sets an optimum gas condition for a vertical rotary surface treatment apparatus that supplies a raw material fluid in a substantially vertical direction to a rotating substrate and performs surface treatment on the substrate,
An acquisition means for acquiring surface treatment parameters including apparatus parameters relating to the shape of the surface treatment apparatus and raw material fluid parameters relating to characteristics of the raw material fluid;
Using the pump effect model of the flow around the rotating disk in the fluid, the axial direction is a characteristic of the axial velocity of the raw material fluid with respect to the distance along the axial direction, with the direction perpendicular to the rotating disk surface as the axial direction. A storage unit for storing a model calculation program for calculating a velocity distribution;
Model calculation means for applying the surface treatment parameters acquired by the acquisition means to the model calculation program and calculating the axial velocity distribution of the raw material fluid with respect to the substrate;
Based on the calculation data of the axial velocity distribution of the raw material fluid with respect to the substrate and the apparatus parameters, the optimal raw material fluid flow rate is calculated for the uniformity of the surface treatment generated on the substrate, and this is set as the optimal flow rate. Optimal flow rate setting means,
A control device for a surface treatment apparatus, comprising: A housing part forming a cylindrical peripheral wall;
A sample holder that is provided inside the housing and holds a substrate that is an object to be surface-treated;
A rotating mechanism for rotating the sample holder;
A source fluid supply flow path section that is provided on the upper side of the sample holder in the housing and supplies a source fluid to the sample of the sample holder;
After the surface treatment is performed on the substrate while the raw material fluid provided as a vertical flow from the upper side of the sample holding table toward the substrate flows along the sample surface, provided on the side of the sample holding table in the housing An outflow channel section for flowing out from the side of the sample holder as a spent fluid;
A control device for setting optimum gas conditions;
With
The control device
An acquisition means for acquiring surface treatment parameters including apparatus parameters relating to the shape of the surface treatment apparatus and raw material fluid parameters relating to characteristics of the raw material fluid;
Using a pump effect model of the flow around a rotating disk in a fluid, the z-direction flow velocity that is a characteristic of the z-direction flow velocity of the raw material fluid with respect to the distance along the z-direction, with the direction perpendicular to the rotating disk surface as the z-direction A storage unit for storing a model calculation program for calculating characteristics;
Model calculation means for applying the surface treatment parameters acquired by the acquisition means to a model calculation program to calculate the z-direction flow velocity characteristics of the source fluid with respect to the substrate;
Based on the calculation data of the z-direction flow velocity characteristics of the raw material fluid with respect to the substrate and the apparatus parameters, the optimal raw material fluid flow rate is calculated for the uniformity of the surface treatment generated on the substrate, and this is set as the optimal flow rate. Optimal flow rate setting means,
A surface treatment system comprising: The surface treatment system according to claim 7, wherein
The control device
A flow rate-variation relationship, which is a relationship between an arbitrary flow rate less than the optimal flow rate and the variation amount for the uniformity of the surface treatment, is obtained in advance, and an allowable variation set from the viewpoint of productivity is set as a threshold variation, and the flow rate-variation relationship is established. A flow rate corresponding to the threshold variation is obtained in advance as a threshold flow rate, and a productivity flow rate setting unit is included for decreasing the flow rate from the optimum flow rate and setting a flow rate equal to the threshold flow rate as the productivity flow rate. Surface treatment system. The surface treatment system according to claim 7, wherein
The control device
A flow rate-variation relationship, which is a relationship between an arbitrary flow rate less than the optimal flow rate and the variation amount for the uniformity of the surface treatment, is obtained in advance, and an allowable variation set from the viewpoint of productivity is set as a threshold variation, and the flow rate-variation relationship is established. Based on this, the flow rate corresponding to the threshold variation is obtained as the threshold flow rate, and the backflow penetration length is defined for the degree of backflow that occurs on the substrate at any flow rate less than the optimal flow rate, and the relationship between the flow rate and the backflow penetration length. A flow rate-reverse flow penetration length relationship that is determined in advance, and based on this flow rate-reverse flow penetration length relationship, a means for obtaining the reverse flow penetration length corresponding to the threshold flow rate as the threshold reverse flow penetration length;
Based on the flow rate-reverse flow penetration length relationship, the reverse flow penetration length was obtained for any flow rate less than the optimal flow rate, and when the obtained reverse flow penetration length was shorter than the threshold reverse flow penetration length, the flow rate was further reduced and obtained. Productivity flow rate setting means for setting a flow rate at which the reverse flow penetration length becomes equal to the threshold reverse flow penetration length as the productivity flow rate;
A surface treatment system comprising:

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