JP2019079867A - Gaseous phase deposition device - Google Patents

Abstract

To provide a gaseous phase deposition device capable of controlling the opposing face temperature to a temperature appropriate for the process uniformly with good repeatability by a large-sized mass production device.SOLUTION: A gaseous phase deposition device is based on a horizontal type or self-revolution type chemical gaseous phase deposition device. In a water-cooled chamber having a process gas introduction part and an exhaust part, a board 220, a susceptor 222 for holding the board, means for heating the board 220 and the susceptor 222, and an opposing face member 20 forming a deposition space (flow channel) oppositely to the board 220 and the susceptor 222, are arranged appropriately. In principle, process gas flows in parallel with the board 220. An irregular shape 22 is formed on the back plane (chamber wall 202 side) of the opposing face member 20, and protrusions 24 thereof are installed to come into contact with the chamber wall 202. Mixed gas (opposing face temperature control gas) composed of two types of gas having different heat conductivity and subjected to flow control is distributed to the recess 26.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a vapor phase deposition apparatus for forming a semiconductor film on a semiconductor or oxide substrate, and more specifically to temperature control of an opposing surface facing the substrate.

  One type of generally used vapor phase deposition apparatus is a type in which a process gas is introduced parallel to the substrate surface. As an example, FIG. 16 shows an example of a cross section of a self-revolution type vapor deposition apparatus, and FIG. 17 shows an example of a plan view of a susceptor of the self-revolution type vapor deposition apparatus. Also, FIG. 18 shows an example of a cross section of a horizontal vapor phase deposition apparatus, and FIG. 19 shows an example of a plan view of a susceptor of the horizontal vapor phase deposition apparatus.

  First, in the self-revolution type vapor deposition apparatus 100 shown in FIGS. 16 and 17, the chamber 110 is water-cooled by the cooling water 104 passing through the chamber member 102. The chamber 110 includes a process gas (or material gas) introduction unit 106, a facing surface temperature control gas introduction unit 150, a purge gas introduction unit 160, and exhaust units 108A and 108B. Further, in the chamber 110, a susceptor 124 for mounting the substrate 120 for film formation and the substrate holder 122, and an opposing surface member 126 having an opposing surface 128 opposing the substrate 120 are appropriately disposed, and are opposed to the susceptor 124 A film forming space (flow channel) 130 is formed between the face members 126. The susceptor 124 is rotated about a rotational shaft 140, and the substrate holder 122 is provided with a mechanism that rotates about the center of the substrate 120.

  On the other hand, in the horizontal vapor phase deposition apparatus 200 shown in FIGS. 18 and 19, the chamber 210 is water-cooled by the cooling water 204 passing through the chamber member 202. The chamber 210 includes a process gas introduction unit 206, an opposing surface temperature control gas introduction unit 250, a purge gas introduction unit 260, and an exhaust unit 208. In the chamber 210, a substrate 220 for film formation, a susceptor 222 for mounting the substrate, and an opposing surface member 226 for forming an opposing surface 228 opposing the substrate 220 are appropriately disposed. A film forming space (flow channel) 230 is formed between the members 226. In the horizontal vapor phase deposition apparatus 200 having the above-described structure, only a mechanism in which the susceptor 222 rotates about the rotation shaft 240 is provided.

  Incidentally, in the vapor phase film formation, the substrate temperature is, of course, an important factor, and accurate and highly reproducible substrate temperature control is required. Substrate heating is usually performed by a heater or heating means such as high frequency heating (heater 170 in FIG. 16, heater 270 in FIG. 18, etc.). In a film forming apparatus (so-called cold wall type) surrounded by a water-cooled wall, the heat generated in the heating means passes through the susceptor (or substrate holder), the substrate, the facing member, and the chamber member in this order to reach the cooling water. Exhausted heat. FIG. 20 shows the flow of heat in the case of a horizontal vapor phase deposition apparatus, and as the heat generated by the heater 270 is indicated by an arrow FA in the figure, the susceptor 222, the substrate 220, and the facing member 226, it passes through the chamber member 202 to the cooling water 204 where it is exhausted. Since the substrate 220 is located between the heater 270 and the facing member 226, if the temperature of the facing member 226 is not stable, the substrate temperature will not be stable.

  The opposing surface temperature also affects very important characteristics in the film forming process, such as the impurity concentration in the film, the deposition rate distribution, and the material efficiency. In chemical vapor deposition, various chemical reactions occur not only on the substrate but also in the vapor phase, that is, in the film formation space. That is, material molecules introduced into the film formation space together with the carrier gas reach various kinds of intermediate reactions and reach the substrate where they are deposited as a film. Therefore, film formation characteristics such as impurity concentration in the film, deposition rate distribution, material efficiency, etc. depend on the chemical reaction history of material molecules in the film formation space, and therefore, if the chemical reaction state in the film formation space is not stable, The characteristics of are also not stable. As a matter of course, the chemical reaction in the film formation space is greatly influenced by the temperature distribution in the film formation space, but the film formation space temperature is determined by the temperature of the susceptor or the substrate and the opposing surface temperature.

  In the "Epitaxial Growth Reactor" of Patent Document 1 below, one method for temperature control of the facing surface is proposed, and this method is generally adopted at present. In this method, an air gap is provided between the opposite surface member and the water-cooled chamber wall, and a mixed gas of a gas having high thermal conductivity and a low gas (opposite surface temperature control gas) is circulated there and the air gap is generated The temperature of the opposing surface is controlled by adjusting the thermal conductivity of In the MOCVD of compound semiconductors, hydrogen is generally employed as a high thermal conductivity gas, and nitrogen is generally employed as a low thermal conductivity gas. That is, in order to control the opposing surface temperature, the ratio of hydrogen and nitrogen of the opposing surface temperature control gas is adjusted. The air gap corresponds to the air gap 180 in FIG. 16 and the air gap 280 in FIG.

Unexamined-Japanese-Patent No. 1-278497

  By the way, in the film formation of the nitride system which is increasing industrial importance recently, the high substrate temperature over 1000 ° C is required. Therefore, the temperature of the film forming space also has to be increased. However, if the temperature of the film formation space is high, the chemical reaction in the gas phase proceeds too much, leading to various adverse effects. For example, in some cases, excessive gas phase reaction inactivates material molecules, resulting in deterioration of material efficiency and film thickness distribution. In another case, the decomposition reaction of material molecules in the gas phase proceeds too much, and the molecular weight reduction accelerates the diffusion rate, resulting in the problem of exhaustion of the material molecules in the upstream region. As described above, since raising the temperature of the film formation space causes various adverse effects, it is necessary to keep the temperature low to some extent.

  The substrate temperature can not be set arbitrarily because the optimum temperature is determined according to the type of film to be formed. Therefore, in order to lower the temperature of the film formation space, it is necessary to lower the opposing surface temperature. Although an appropriate value of the facing surface temperature depends on the film forming object, in the case of a nitride based film, the facing surface temperature of about 200 to 250 ° C. is empirically appropriate. In order to achieve a substrate temperature of 1000 ° C. or more and a low opposing surface temperature of about 200 to 250 ° C., it is necessary to narrow the air gap through which the opposing surface temperature control gas flows. If the air gap is wide, even if only hydrogen having high thermal conductivity is circulated as the facing surface temperature control gas, the facing surface temperature exceeds the appropriate temperature range.

  FIG. 21 shows the relationship between the gap and the control temperature with respect to the gap under film forming conditions of a general nitride-based compound semiconductor. In the figure, the horizontal axis is the gap width (mm), and the vertical axis is the lower limit value and the upper limit value (° C.) of the facing surface temperature. In the drawing, the solid line portion indicates the lower limit value of the opposing surface temperature, that is, the opposing surface temperature when the opposing surface temperature control gas is 100% hydrogen. The broken line portion indicates the upper limit value of the opposing surface temperature, which is the opposing surface temperature when the opposing surface temperature control gas is 100% nitrogen. From FIG. 21, it can be seen that an appropriate temperature having an opposing surface temperature of 200 to 250 ° C. is finally obtained with a gap width of 0.1 to 0.2 mm.

  On the other hand, in recent years, there has been a strong demand for enlargement of nitride-based film forming apparatuses, and in current mass production apparatuses, the size of the facing member has reached a diameter of 700 mm to 1 m depending on the case. It is very difficult to uniformly form a narrow gap of about 0.1 to 0.2 mm over such a wide range in consideration of the processing accuracy of the member. Also, in any case, slight thermal deformation of the facing member due to heating can not be avoided, and if the gap width is narrow, even slight thermal deformation is greatly affected. From these points, there is a problem that it is difficult to control the facing surface temperature uniformly and reproducibly in a large-scale mass-production apparatus by the conventional method.

  The present invention focuses on the above points, and provides a vapor phase deposition apparatus capable of controlling the facing surface temperature to a temperature appropriate for the process, with large-scale mass-production apparatus, uniformly and with good reproducibility. Its purpose.

  The present invention relates to a susceptor for holding a substrate for film formation in a chamber inner space having a source gas introduction portion and an exhaust portion and surrounded by a water-cooled wall, and the susceptor and the substrate for film formation. Gas phase film deposition apparatus in which an opposing surface member forming a horizontal flow channel is disposed, wherein the opposing surface temperature control gas for controlling the temperature of the opposing surface member is introduced into the chamber. A surface temperature control gas introduction unit, and an uneven shape is formed on the surface of the facing surface member not facing the substrate, and a convex portion is disposed to contact the water-cooled wall surface, and a concave portion is formed It is characterized in that it is a flow path of the controlled opposite surface temperature control gas.

  One of the main modes is characterized in that the opposed surface temperature control gas is a mixed gas composed of two or more kinds of gases having different thermal conductivities. One of the other modes is characterized in that the opposite surface temperature control gas comprises hydrogen and nitrogen. In still another mode, in a region of the facing surface member facing the substrate, an area ratio of a contact portion with the convex portion in the region to the entire area of the region is 0.3 to 0. It is characterized by being .6.

  Still another aspect is characterized in that the height of the convex portion is 2 mm or less. Still another aspect is characterized in that a film formation target is formed on the substrate by an organic metal vapor phase deposition method. Furthermore, one of the other modes is characterized in that an object to be deposited on the substrate is a nitride-based compound semiconductor. The above and other objects, features and advantages of the present invention will be apparent from the following detailed description and the accompanying drawings.

  According to the present invention, there is provided a susceptor for holding a substrate for film formation in a chamber interior space having a source gas introduction portion and an exhaust portion and surrounded by a water cooled wall, the susceptor and the substrate for film formation A vapor deposition apparatus in which is disposed an opposing surface member that forms a flow channel in the horizontal direction with respect to the surface, and introducing an opposing surface temperature control gas for controlling the temperature of the opposing surface member into the chamber Forming a convex-concave shape on the surface of the counter-surface member not facing the substrate, and arranging the convex portion to be in contact with the water-cooled wall surface; The flow path of the opposite surface temperature control gas whose flow rate is controlled. Therefore, it is possible to provide a vapor phase deposition apparatus capable of controlling the facing surface temperature to a temperature suitable for the process uniformly and with high reproducibility in a large-scale mass production apparatus.

FIG. 1 is a cross-sectional view showing the basic concept of the present invention. It is sectional drawing which shows the self-revolution type | mold vapor-phase film-forming apparatus of Example 1 of this invention. It is a top view which shows an example of the uneven | corrugated shape of the opposing surface member of the said Example 1. FIG. FIG. 4 is a cross-sectional view of FIG. 3 taken along the # A- # A line and viewed in the arrow direction. It is a top view which shows the other example of the uneven | corrugated shape of the opposing surface member of the said Example 1. FIG. It is sectional drawing which shows the horizontal-type vapor-phase film-forming apparatus of Example 2 of this invention. It is a top view which shows an example of the uneven | corrugated shape of the opposing surface member of the said Example 2. FIG. It is a top view which shows the other example of the uneven | corrugated shape of the opposing surface member of the said Example 2. FIG. It is explanatory drawing for determining the area | region which performs simulation of this invention. It is sectional drawing which shows the simulation model of this invention. It is a figure which shows an example of the two-dimensional temperature distribution map in the said simulation model. It is a figure which shows the relationship between the area ratio of a convex part (contact part) with respect to the whole area in the said simulation, and opposing surface temperature. It is a figure which shows the relationship between the area ratio of a convex part (contact part) with respect to the whole area in the said simulation, and opposing surface temperature control width. It is a figure which shows the relationship between the area ratio of the convex part (contact part) with respect to the whole area in the said simulation, and the magnitude | size (control gas: hydrogen) of opposing surface surface temperature distribution. It is a figure which shows the relationship between the area ratio of the convex part (contact part) with respect to the whole area in the said simulation, and the magnitude | size (control gas: nitrogen) of opposing surface surface temperature distribution. It is sectional drawing of a general self-revolution type | mold vapor-phase film-forming apparatus. It is a top view of the susceptor of the self-revolution type | mold vapor-phase film-forming apparatus of FIG. It is sectional drawing of a general horizontal vapor phase film-forming apparatus. FIG. 19 is a plan view of a susceptor of the horizontal vapor phase deposition apparatus of FIG. 18; It is sectional drawing which shows the flow of the heat in the conventional gaseous-phase film-forming apparatus. It is a graph which shows the space | gap width of the chamber member and opposing surface in the conventional vapor phase film-forming apparatus, and the relationship of the lower limit and upper limit of opposing surface temperature.

  Hereinafter, the best mode for carrying out the present invention will be described in detail based on examples.

  <Basic Concept> First, the basic concept of the present invention will be described with reference to FIG. FIG. 1 is a cross-sectional view showing the basic concept of the present invention. The present invention basically has a film forming apparatus based on a horizontal or self-revolving chemical vapor deposition apparatus (FIG. 1 shows an example of a horizontal vapor deposition apparatus). That is, in a water-cooled chamber having a process gas introduction part and an exhaust part, the substrate 220, the susceptor 222 for holding the substrate, a means for heating the substrate 220 and the susceptor 222, and film formation facing the substrate 220 and the susceptor 222 It is the structure which has arrange | positioned suitably the opposing surface member 20 which forms space. The flow direction of the process gas is in principle parallel to the substrate.

  As described above, in the prior art, an air gap (air gap 180 in FIG. 16 and air gap 280 in FIG. 18) is provided between the back surface of the facing member and the chamber member, and the temperature control gas is circulated there to obtain the temperature. Although control is performed, conventionally, the back surface of the facing member was flat. On the other hand, in the present invention, the concavo-convex shape 22 is formed on the back surface (the chamber member 202 side) of the facing surface member 20, and the convex portion 24 is placed in contact with the chamber member 202. Then, mixed gas (facing surface temperature control gas) composed of two kinds of gases having different thermal conductivities is caused to flow through the recess 26 to control the facing surface temperature.

  The control lower limit value of the facing surface temperature is obtained when flowing only hydrogen (ie, 100% hydrogen) having the highest thermal conductivity. In the present invention, the facing member 20 is in partial contact, and since the facing member 20 is solid, it has a thermal conductivity much higher than that of hydrogen gas. That is, heat transfer is good. Since the heat transfer facing surface member 20 partially contacts the chamber member 202, the effective heat transfer from the facing surface member 20 to the chamber member 202 is improved. Accordingly, even if the height difference of the recess 26 which is the noncontact portion is increased, it is possible to realize the same heat conductivity as the effective heat conductivity when the gap width is made narrow in the conventional method. In terms of calculation, in the present invention, in order to obtain an opposing surface temperature of about 200 to 250 ° C. under nitride-based film forming conditions, it is sufficient to form an unevenness having a height difference of about 1 mm. This point will be described in detail in the description of the simulation described later.

  <Example of application to self-revolution type vapor phase film forming apparatus> First, the self-revolution type vapor phase film forming apparatus 10 will be described with reference to FIGS. FIG. 2 is a cross-sectional view showing a self-revolution type vapor deposition apparatus. FIG. 3: is a top view which shows an example of the uneven | corrugated shape of an opposing surface member. FIG. 4 is a cross-sectional view of FIG. 3 taken along the # A- # A line and viewed in the arrow direction. FIG. 5 is a plan view showing another example of the concavo-convex shape of the facing surface member.

  First, the basic configuration of the self-revolution type vapor deposition apparatus 10 of this embodiment is the same as that of the above-described prior art (FIGS. 16 and 17). That is, as shown in FIG. 2, in the self-revolution type vapor deposition apparatus 10, the chamber 110 is water-cooled by the cooling water 104 passing through the chamber member 102. The chamber 110 includes a process gas (or material gas) introduction unit 106, a facing surface temperature control gas introduction unit 150, a purge gas introduction unit 160, and exhaust units 108A and 108B. In the chamber 110, a susceptor 124 for mounting a substrate 120 for film formation and a substrate holder 122, and an opposing surface member 20 having an opposing surface 21 opposing the substrate 120 are appropriately disposed, and are opposed to the susceptor 124 A film forming space (flow channel) 130 is formed between the face members 126. The susceptor 124 is rotated about a rotational shaft 140, and the substrate holder 122 is provided with a mechanism that rotates about the center of the substrate 120.

  In the present invention, in addition to the above configuration, the uneven shape 22 is provided on the upper side (the chamber member 102 side) of the facing surface member 20. The facing surface member 20 is installed so that the convex portion 24 of the concavo-convex shape 22 contacts the water cooled chamber member 102, and the facing surface temperature control gas is circulated in the concave portion 26.

  As one example of the form of the concavo-convex shape 22, as shown in FIG. 3, there is a form in which a large number of island-shaped (or dot-shaped) convex portions 24 are provided. The cross section of FIG. 3 cut along the # A- # A line and viewed in the direction of the arrow is shown in FIG. 4, and the projections 24 and the recesses 26 are regularly arranged. In addition, in FIG. 3, although the planar shape of the convex part 24 is circular, even if it is a quadrangle etc., for example, since an effect is the same, you may be set as arbitrary shapes. In addition, although the arrangement of the convex portions 24 is a lattice-like periodic arrangement in FIG. 3, any arrangement may be used as long as the uniformity of temperature is ensured. Further, even if the shape is not island-like, as in the facing surface member 20A shown in FIG. 5, concave portions 26A whose width gradually widens from the central opening 28 toward the outer edge are radially arranged. It may be in the shape of In this case, the protrusions 24A are also radial.

  <Example of Application to Horizontal-Type Vapor-Phase Film Forming Apparatus> Next, an example of application to the horizontal-type vapor-phase film forming apparatus 50 will be described with reference to FIGS. FIG. 6 is a cross-sectional view showing a horizontal vapor phase deposition apparatus. FIG.7 and FIG.8 is a figure which shows an example of the uneven | corrugated shape of an opposing surface member. The basic configuration of the horizontal vapor phase deposition apparatus 50 of this example is the same as that of the above-described prior art (FIGS. 18 and 19). That is, as shown in FIG. 6, in the self-revolution type vapor deposition apparatus 50, the chamber 210 is water-cooled by the cooling water 204 passing through the chamber member 202. The chamber 210 includes a process gas introduction unit 206, an opposing surface temperature control gas introduction unit 250, a purge gas introduction unit 260, and an exhaust unit 208. In the chamber 210, a substrate 220 for film formation, a susceptor 222 for mounting the substrate, and an opposing surface member 60 for forming an opposing surface 61 opposed to the substrate 220 are properly disposed. A film forming space (flow channel) 230 is formed between the members 226. In the horizontal vapor phase deposition apparatus 200 having the above-described structure, only a mechanism in which the susceptor 222 rotates about the rotation shaft 240 is provided.

  In the present invention, in addition to the above configuration, the uneven shape 62 is provided on the upper side (the chamber member 202 side) of the facing surface member 60. The facing surface member 60 is installed so that the convex portion 64 of the concavo-convex shape 62 is in contact with the water-cooled chamber member 202, and the facing surface temperature control gas is circulated in the concave portion 66. As a specific pattern of the concavo-convex shape 62, for example, as shown in FIG. 7, there is a shape in which convex portions 64 are periodically arranged in a lattice shape. The cross section of FIG. 7 cut along the # B- # B line and viewed in the arrow direction is the same as FIG. Further, as in the facing surface member 60A shown in FIG. 8, a plurality of convex portions 64A extended in the flow direction of the process gas may be provided in parallel. In this case, the plurality of recesses 66A are also arranged in parallel.

  <Material of Each Part>... Next, the material of each part will be described. As an example of the chamber material, generally used stainless steel may be used, or aluminum or the like may be used if good thermal conductivity is required. For the susceptor or the substrate holder, a carbon-based material such as graphite is suitable. If the film formation target is a nitride type, and ammonia is used as a process gas, it is corroded by ammonia if a carbon material is used. In this case, it is resistant to ammonia such as silicon carbide, boron nitride or tantalum carbide. It is preferable to use a carbon material coated with a substance. Similar to the susceptor, as the facing surface member, a carbon material or a carbon material coated with another material as described above is preferable, but other materials such as quartz, various ceramics, various metal materials, etc. may be used under the process environment. It can be used if it is resistant.

  <Simulation>... An important design element in practicing the present invention is a convex portion (hereinafter simply referred to as "whole") in the region facing the substrate in the facing surface member. It is an area ratio of a contact part and height of a convex part. Moreover, since the period of the unevenness is related to the temperature distribution on the facing surface, this is also one of the design parameters. The nature of these design parameters will be described in detail in the following simulation example.

  As mentioned earlier, the area ratio of the ridge to the whole is important for the controllable temperature of the facing surface temperature. It is considered that the lower the control temperature lowers and the controllable range becomes smaller as the area ratio of the projections becomes larger. In addition, as the height of the convex portion, the lower the height, the lower the opposing surface temperature, and the higher the height, it is considered to become higher. Therefore, it may be used as a parameter for obtaining a desired opposing surface temperature. Therefore, in the present embodiment, a simulation model was set, the area ratio of the projections and the height of the projections were changed, and the influence of these parameters on the opposing surface temperature was examined. In addition, since the temperature distribution on the surface of the opposite surface (the side facing the susceptor and the substrate) is considered to be formed by the uneven shape on the back surface of the opposite surface, the temperature distribution on the surface of the opposite surface was also studied.

  In this simulation, it is assumed that an aspect (a form similar to FIG. 8) in which groove-type asperities are formed on the opposite surface is applied to a horizontal vapor phase deposition apparatus which is an embodiment of the present invention. FIGS. 9 (a) and 9 (b) are explanatory diagrams for determining an area to perform this simulation. Since a general self-revolution type vapor deposition apparatus and a horizontal vapor deposition apparatus have a shape which spreads in the horizontal direction, substantial horizontal heat transfer can be substantially ignored. Then, considering the periodicity of the concavo-convex shape, it is considered sufficient to solve a two-dimensional model for a half cycle perpendicular to the extension direction of the groove. In addition, the conclusions from the model are assumed to be applicable to other embodiments, given that substantial lateral heat transfer is negligible. In addition, the area | region (simulation area | region 68) to which simulation was applied is an area | region shown by the thick broken line in FIG.9 (b).

  FIG. 10 is a cross-sectional view showing the details of this simulation model. Each dimension shown in the same figure is a general dimension used in the actual MOCVD method. That is, the distance from the susceptor or substrate 220 to the opposing surface 61 (ie, the height of the film forming space) is 15 mm, the total thickness of the opposing surface member 60A including the concavo-convex structure is 10 mm, and the thickness of the chamber member 202 is 10 mm. One side of the chamber member 202 is in contact with the cooling water 204. A thermal contact resistance always occurs between the surface of the facing member 60A and the surface of the chamber member 202. Since the origin of the contact resistance is a micro air gap that inevitably occurs between two objects in contact, in this simulation, a 0.01 mm air gap is represented as existing between the facing member 60A and the chamber member 202. did. This is considered to be an empirically reasonable number. In addition, the contact resistance can be adjusted to some extent by the surface roughness of the member and the like.

Physical property values of each part of the model were set as follows based on the physical properties of each material generally disclosed.
(1) The emissivity from the susceptor (substrate 220) is assumed to be 0.85, assuming a carbon-based material.
(2) The thermal conductivity of the space which is the film formation region is 0.235 W / m / s, assuming hydrogen which is most commonly used as a carrier gas.
(3) Assuming that the opposite surface member 60A is a carbon-based material, the emissivity is 0.85 and the thermal conductivity is 100 W / m / s.
(4) The region (concave portion 66A) in which the opposing surface temperature control gas flows is performed for two patterns of hydrogen and nitrogen, and at that time, the thermal conductivity of 0.235 and 0.034 is set.
(5) Assuming that the chamber member 202 is stainless steel, the emissivity is 0.4 and the thermal conductivity is 17 W / m / s.
(6) Regarding temperature boundary conditions, the high temperature side is the susceptor (substrate 220) surface, which is 1050 ° C., and the low temperature side is the interface of the chamber member 102 and the cooling water 204, which is 40 ° C.

  Among the above-mentioned physical properties, even when the carbon-based member is covered with another material, for example, since the thickness of the coating is thin, the thermal conductivity may be considered to be the same as that of the carbon material. With regard to emissivity, silicon carbide coatings are almost the same as carbon materials, and boron nitride coatings do not differ much from the emissivity of carbon if the coating thickness is small. In other words, it is considered that, under the use of these materials, substantially similar results to simulation can be obtained in reality.

  The simulation was carried out for various surface area ratios and heights using the above model and physical property values. In this simulation, only the heat conduction is handled in the facing surface member 60A and the chamber member 202 which are opaque bodies, and the space between the facing surface member 60A and the chamber member 202 is filled with a gas filled with a gas which is a transparent body. In addition to the heat conduction through the gas, the heat transfer by radiation was also taken into account.

  FIG. 11 shows an example of the temperature distribution of the portion from the heater to the cooling water obtained as a result of the simulation. In order to make it easy to understand, two different temperature display scales are shown. In this example, the convex area ratio is 0.5, the convex height is 1 mm, and the temperature control gas for the facing surface is calculated under the condition of 100% hydrogen. The same simulation was performed for each condition, and from the obtained results, the effects of the convex area ratio and the convex height on the surface temperature of the facing surface are summarized in FIGS. 12 to 15. In each of these drawings, the horizontal axis is the area ratio of the convex portion (contact portion) to the entire area (hereinafter referred to as "the convex area ratio").

FIG. 12 is a diagram showing the relationship between the area ratio of the convex portion to the total area and the temperature (° C.) of the facing surface (vertical axis). Note that, in the drawing, the opposing surface temperatures of both the opposing surface temperature control gas H ₂ and N ₂ are shown. According to FIG. 12, it can be seen that the opposing surface temperature becomes higher as the contact area ratio becomes smaller as expected. That is, by appropriately selecting the area ratio, it is possible to obtain a control temperature range of any facing surface temperature. It is understood that a convex portion area ratio of 0.3 to 0.6 is appropriate to achieve 200 to 250 ° C.

  FIG. 13 is a diagram showing the relationship between the convex portion area ratio and the facing surface temperature control width (° C.) (vertical axis). According to the figure, the smaller the area ratio, the larger the control range, which is preferable in that respect. The area ratio to be used in practice is to determine the lowest area ratio in consideration of both the temperature range and the control range. Further, it can also be seen from FIG. 13 that the control width has a small height dependency of the convex portion. In other words, it can be seen that even if the height of the convex portion is increased, the control width does not work so advantageously.

  FIG. 14 and FIG. 15 are diagrams showing the relationship between the convex portion area ratio and the size (° C.) (vertical axis) of the temperature distribution on the facing surface. FIG. 14 shows the difference between the maximum temperature and the minimum temperature of the facing surface temperature when the facing surface control gas is hydrogen, and FIG. 15 shows the case where the facing surface control gas is nitrogen. Naturally, the temperature is low in the vicinity of the convex portion (contact portion), and the temperature is high in the concave portion. According to this, as the height of the convex portion is higher, the temperature difference in the surface of the facing surface is larger. That is, when the height of the convex portion is high, the control width does not change so much, which means that the temperature distribution on the surface of the facing surface is deteriorated, and it is understood that the height of the convex portion should not be too high. Judging from FIGS. 14 and 15, the height of the convex portion is considered to be 2 mm or less. From the viewpoint of processing accuracy, the larger the height of the convex portion, the better, but at 2 mm or more, the adverse effect of the deterioration of the surface temperature distribution can not be ignored.

  As described above, in the case of the nitride film forming process, the temperature of the opposing surface is preferably about 200 to 250 ° C. It is understood from FIGS. 12 to 15 that in order to meet the conditions, the area ratio of the contact portion (convex portion) is 0.3 to 0.6, and the height of the convex portion is 2 mm or less. . The optimum values of the area ratio of the projections and the height of the projections vary depending on the target film forming species, the material used as the facing surface member, or the film forming conditions, but in many cases, they are set within the above range Is considered appropriate.

  Thus, according to the first embodiment, the following effects can be obtained. That is, in the conventional method, a narrow gap width of about 0.1 to 0.2 mm must be realized uniformly over a large area, so that precise processing accuracy is required. On the other hand, according to the present invention, since a relatively large height difference of about 2 mm is sufficient, the degree of processing difficulty is greatly reduced. Therefore, good uniformity of the facing surface temperature over a large area can be obtained at low cost. Further, unlike the conventional method, the area in contact with the chamber wall is large, so that the reproducibility and the stability of the installation are increased. As described above, according to the present embodiment, even with a large-area facing surface, the facing surface temperature of about 200 to 250 ° C. can be realized with good uniformity and good reproducibility.

The present invention is not limited to the embodiments described above, and various modifications can be made without departing from the scope of the present invention. For example, the following are also included.
(1) The shapes and dimensions shown in the above embodiments are also examples and may be changed as needed.
(2) In the above embodiments, the self-revolution type vapor deposition apparatus and the horizontal vapor deposition apparatus have been described as an example, but in the present invention, a (film deposition space) flow channel in the horizontal direction is formed. Applicable to all reactors.
(3) The materials of the respective parts, the process gas, the facing surface temperature control gas, and the purge gas shown in the above embodiments are merely examples, and can be appropriately changed within the range where the same effects can be obtained.
(4) The concavo-convex shape shown in the above embodiment is also an example, and design changes can be made as appropriate within the range where the same effect can be obtained.

  According to the present invention, there is provided a susceptor for holding a substrate for film formation in a chamber interior space having a source gas introduction portion and an exhaust portion and surrounded by a water cooled wall, the susceptor and the substrate for film formation A vapor deposition apparatus in which is disposed an opposing surface member that forms a flow channel in the horizontal direction with respect to the surface, and introducing an opposing surface temperature control gas for controlling the temperature of the opposing surface member into the chamber Forming a convex-concave shape on the surface of the counter-surface member not facing the substrate, and arranging the convex portion to be in contact with the water-cooled wall surface; The flow path of the opposite surface temperature control gas whose flow rate is controlled. For this reason, since it is possible to control the facing surface temperature to a temperature suitable for the process uniformly and reproducibly, it can be applied to the application of the vapor deposition apparatus. In particular, it is suitable for use in large-scale mass production equipment.

10: self-revolution type gas phase film forming apparatus 20, 20A: opposing surface member 21: opposing surface 22: uneven shape 24, 24A: convex portion (contact portion)
26, 26A: Recess (Temperature control gas flow path)
28: Opening 50: Horizontal type vapor phase deposition apparatus 60, 60A: Opposite surface member 61: Opposite surface 62: Irregular shape 64, 64A: Convex portion 66, 66A: Recess 68: Simulation region 100: Self-revolution type vapor phase composition Film apparatus 102: Chamber member 104: Cooling water 106: Process gas introduction part 108A, 108B: Exhaust part 110: Chamber 120: Substrate (substrate for film formation)
122: substrate holder 124: susceptor 126: facing surface member 128: facing surface 130: space for film formation (flow channel)
140: rotating shaft 150: opposing surface temperature control gas introducing unit 160: purge gas introducing unit 170: heater 180: air gap 200: horizontal type vapor phase film forming apparatus 202: chamber member 204: cooling water 206: process gas introducing unit 208: exhaust unit 210: Chamber 220: Substrate for film formation 222: Susceptor 226: Opposite surface member 228: Opposite surface 230: Space for film formation (flow channel)
240: Rotating shaft 250: Opposite surface temperature control gas introduction unit 260: Purge gas introduction unit 270: Heater 280: Air gap

Claims (7)

A susceptor for holding a substrate for film formation in a chamber space having a source gas introduction portion and an exhaust portion and surrounded by a water-cooled wall, and a direction horizontal to the susceptor and the substrate for film formation A vapor phase deposition apparatus in which opposing surface members forming a flow channel are disposed,
An opposing surface temperature control gas introduction unit for introducing an opposing surface temperature control gas for controlling the temperature of the opposing surface member into the chamber;
As well as
An uneven shape is formed on the surface of the opposing surface member not opposing the substrate, and a convex portion is disposed so as to contact the water-cooled wall surface, and a concave portion is controlled by the flow of the opposing surface temperature control gas. A vapor phase deposition apparatus characterized in that it has a channel. The facing surface temperature control gas is
The vapor deposition apparatus according to claim 1, wherein the vapor deposition apparatus is a mixed gas composed of two or more kinds of gases having different thermal conductivities. The facing surface temperature control gas is
The vapor phase film forming apparatus according to claim 2, characterized in that it comprises hydrogen and nitrogen. In a region facing the substrate in the facing surface member,
The area ratio of the contact part with the said convex part in the said area | region with respect to the total area of this area | region is 0.3-0.6, It is characterized by the above-mentioned. Gas phase film deposition system.   The vapor deposition apparatus according to any one of claims 1 to 4, wherein the height of the convex portion is 2 mm or less.   The vapor phase film forming apparatus according to any one of claims 1 to 5, wherein a film forming target is formed on the substrate by a metal organic vapor phase film forming method.   The vapor phase deposition apparatus according to any one of claims 1 to 6, wherein an object to be deposited on the substrate is a nitride compound semiconductor.