TWI682059B - Vapor phase film deposition apparatus - Google Patents

Abstract

The invention will provide a gas-phase film-forming device, which uses a large-scale production device to control the temperature of the opposite surface to a temperature suitable for the process with excellent uniformity and repeatability. The gas-phase film-forming device is mainly a horizontal or rotation type gas-phase film-forming device. In a water-cooled chamber with a process gas introduction part and an exhaust part, a substrate 220, a carrier 222 holding the substrate, a device for heating the substrate 220 and the carrier 222, and The substrate 220 and the carrier 222 face each other and have a structure of the facing member 20 in which a film forming space (fluid channel) is formed. In principle, the process gas flows parallel to the substrate 220. On the reverse surface of the opposing surface member 20 (the chamber wall 202 side), a concave-convex shape 22 is formed, and is provided so that the convex portion 24 is in contact with the chamber wall 220. In addition, a mixed gas (contrast surface temperature control gas) composed of two kinds of gas whose thermal conductivity is controlled by flow rate can be circulated in the recess 26.

Description

Gas-phase film forming device

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

As a form of a general gas-phase film forming apparatus, there is a form in which a process gas is introduced parallel to the surface of the substrate. Examples of this are shown in FIGS. 16 to 19 below. FIG. 16 is a cross-sectional example of a self-rotating vapor-phase film forming apparatus, and FIG. 17 is a plan view example of a carrier of the self-rotating vapor-phase film forming apparatus. In addition, FIG. 18 is a cross-sectional example showing a vapor-phase film forming apparatus in a lateral direction, and FIG. 19 is a plan view example showing a carrier of the lateral vapor-phase film-forming apparatus.

First, on the self-rotating vapor-phase film forming apparatus 100 shown in FIGS. 16 and 17, the chamber 110 is cooled by the cooling water 104 passing through the chamber member 102. The chamber 110 includes a process gas (or material gas) introduction part 106, a pair of surface temperature control gas introduction parts 150, a purge gas introduction part 160, and exhaust parts 108A and 108B. In addition, in the chamber 110, a carrier 124 is disposed, which houses the film-forming substrate 120 and the substrate fixing base 122; and a pair of facing members 126, which are opposite to the substrate 120 The opposite surface 128 forms a film-forming space (fluid channel) 130 between these bearing seats 124 and the opposite surface member 126. The carrier 124 is provided with a mechanism for rotating around a rotating shaft 140, and the substrate fixing base 122 is provided with a mechanism for rotating around the center of the substrate 120.

On the other hand, in the lateral gas-phase film forming apparatus 200 shown in FIGS. 18 and 19, the chamber 210 is cooled by the cooling water 204 passing through the chamber member 202. The chamber 210 includes a process gas introduction part 206, a pair of surface temperature control gas introduction parts 250, a purge gas introduction part 260, and an exhaust part 208. In addition, in the chamber 210, a carrier 222 on which the film-forming substrate 220 and the like are placed; and a pair of facing members 226, which form an opposite to the substrate 220 The surface 228 forms a film-forming space (fluid channel) 230 between the carrier 222 and the opposite surface member 126. In the structure of the above-mentioned horizontal-type vapor-phase film-forming apparatus 200, only a mechanism for rotating the carrier 222 around the rotating shaft 240 is provided.

In addition, in vapor-phase film formation, it goes without saying that the substrate temperature is an important factor and requires both precise and repeatable substrate temperature control. Substrate heating is generally performed by a heating device such as a heater or high-frequency heating (as shown in heater 170 in FIG. 16, heater 270 in FIG. 18, etc.). In a film-forming device (so-called cold-wall type) surrounded by a water-cooled wall, the heat generated in the heating device arrives in the order of the carrier (or substrate fixing seat), the substrate, the surface-facing member and the chamber member Cooling water, here to remove heat. 20 is a diagram showing the heat flow in the case of a gas-phase film-forming apparatus in a horizontal bedroom. The heat generated by the heater 270 passes through the carrier 222, the substrate 220, the surface-facing member 226 and The chamber member 202 reaches the cooling water 204, where heat is removed. Since the substrate 220 is located between the heater 270 and the facing member 226, if the temperature of the facing member 226 is unstable, the substrate temperature will also be unstable.

The opposite surface temperature also affects very important characteristics in the film formation step, such as the impurity concentration in the film, the deposition rate distribution, and the material efficiency. In chemical vapor deposition, various chemical reactions not only occur on the substrate, that is to say, they also occur in the vapor phase, that is, in the film formation space. In other words, the material molecules introduced into the film-forming space together with the carrier gas reach the substrate after undergoing various intermediate reactions, and serve as a place for stacking the film. Therefore, the thin film characteristics of thin film impurity concentration, deposition rate distribution, material efficiency, etc., the chemical reaction process of material molecules existing in the film formation space, therefore, if the chemical reaction state in the film formation space is unstable, these characteristics Also unstable. And, of course, although the chemical reaction in the film forming space is greatly affected by the temperature distribution of the film forming space, the temperature of the film forming space is determined by the temperature of the carrier or the substrate and the temperature of the opposite surface.

In the "Epitaxial Growth Reactor" described in Patent Document 1 below, a method for controlling the temperature of the opposite surface will be disclosed, which is currently commonly used. In this method, a gap is provided between the opposite surface member and the water-cooled chamber wall, where a mixed gas with a gas having a higher thermal conductivity and a gas with a lower thermal conductivity is provided (temperature control of the opposite surface) Gas) circulation, the temperature of the opposite surface is controlled by adjusting the thermal conductivity of the void by the mixing ratio. In MOCVD of compound semiconductors, hydrogen is generally used as a gas with a high thermal conductivity, while nitrogen is generally used as a gas with a low thermal conductivity. In other words, in order to control the temperature of the opposite surface, it is necessary to adjust the ratio of the hydrogen gas and nitrogen of the opposite temperature control gas. This gap corresponds to the gap 180 in FIG. 16 and the gap 280 in FIG. 18. [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 1-278497

At the same time, in recent years, in the formation of nitride-based films of increasing industrial importance, a high substrate temperature of more than 1000°C is required. Therefore, the temperature of the film formation space must also be increased. However, when the temperature of the film-forming space increases, the chemical reaction in the gas phase will proceed excessively and cause various harmful effects. For example, in some cases, material molecules will be inactivated due to excessive gas-phase reactions, which in turn leads to deterioration in material efficiency or film thickness distribution. In another case, the decomposition reaction of the material molecules is excessively performed in the gas phase, and the diffusion speed is accelerated due to the lower molecular weight. As a result, the problem arises that the material molecules wither in the upstream region. In this way, since the high temperature of the film-forming space will cause various harmful effects, it must be kept at a certain low temperature.

Since the optimum temperature of the substrate temperature depends on the type of thin film to be formed, it cannot be arbitrarily set. Therefore, in order to lower the temperature of the film formation space, it is necessary to lower the temperature of the opposite surface. Although the appropriate value of the opposite surface temperature depends on the film formation target, in the case of a nitride-based object, according to experience, the opposite surface temperature is about 200 to 250°C. In order to achieve a substrate temperature of 1000°C or more and a low temperature of about 200 to 250°C, it is necessary to reduce the gap in which the opposite temperature control gas flows. If the gap is wide, even if only the hydrogen with high thermal conductivity is used as the opposite surface temperature control gas, the opposite surface temperature will exceed the appropriate temperature range.

FIG. 21 shows the relationship between the void under the film-forming conditions of the ordinary nitride-based compound semiconductor and the control temperature of the void. In the same, the horizontal axis represents the width of the gap (mm); the vertical axis represents the lower limit value and the upper limit value (°C) of the temperature of the opposite surface. In this figure, the solid line indicates the lower limit value of the opposite surface temperature, but this value is the opposite surface temperature when the opposite surface temperature control gas is set to 100% hydrogen. In addition, although the dotted line indicates the upper limit of the opposite surface temperature, this value is the opposite surface temperature when the opposite surface temperature control gas is set to 100% hydrogen. As can be seen from FIG. 21, when the gap width is 0.1 to 0.2 mm, an appropriate temperature of the opposite surface temperature of 200° C. to 250° C. can be easily obtained.

On the other hand, in recent years, there has been a strong demand for the enlargement of nitride-based film-forming devices, and in the current production devices, the size of the facing member has reached a diameter of 700 mm, and sometimes even reached 1 m. In such a wide range, it is necessary to uniformly form a narrow gap of about 0.1 to 0.2 mm, and if the processing precision of the component is taken into consideration, it is very difficult. In addition, in any case, the slight thermal deformation of the facing member due to heating cannot be avoided, and if the gap width is narrowed, even a slight thermal deformation will be greatly affected by this. From these points of view, there is a problem that it is difficult to control the temperature of the opposite surface with uniformity and repeatability by a large-scale production device of the conventional method.

The present invention was invented in view of the above problems, and its object is to provide a gas-phase film-forming device that uses a large-scale production device to control the temperature of the opposite surface to a suitable level with characteristics of uniformity and repeatability. The temperature of the process.

The gas-phase film-forming device of the present invention is equipped with a susceptor, which has a material gas introduction part and an exhaust part, and has a chamber space surrounded by a water-cooled wall surface for maintaining A film substrate; and a pair of facing members forming a flow channel in a horizontal direction with respect to the carrier and the film-forming substrate; wherein, in the chamber, a pair of facing temperature control gas introduction parts are provided , Which introduces the opposite surface temperature control gas for controlling the temperature of the opposite surface member, and at the same time, a concave-convex shape is formed on the surface of the opposite surface member that is not opposite to the substrate, so that the convex portion is arranged to be The water-cooled wall surface is in contact, and the concave portion is used as a flow path of the temperature control gas of the opposite surface for flow control.

The main form is characterized by the temperature control gas system of the opposite surface is a mixed gas composed of two or more kinds of gases with different thermal conductivity. Another form is characterized in that the opposite temperature control gas includes hydrogen and nitrogen. In still another form, it is characterized in a region facing the substrate of the facing member, wherein the area ratio of the contact portion with the convex portion in the region is 0.3 to 0.6 .

In yet another form, the feature is that the height of the convex portion is 2 mm or less. In yet another aspect, the feature is that an object of film formation is formed on the substrate by an organic metal vapor phase film formation method. In yet another aspect, the object of film formation on the substrate is a nitride-based compound semiconductor. The foregoing and other objects, features, and advantages of the present invention will be apparent from the following detailed description and accompanying drawings. [Effect of the invention]

If the gas-phase film-forming apparatus according to the present invention is equipped with a susceptor, which has a material gas introduction part and an exhaust part, and has a space in the chamber space surrounded by the water-cooled wall surface To hold the substrate for film formation; and a pair of facing members to form a flow channel (Flow channel) in a horizontal direction relative to the carrier and the substrate for film forming; wherein, in the chamber, a pair of facing temperature controls are provided The gas introduction part introduces the opposite surface temperature control gas for controlling the temperature of the opposite surface member, and at the same time, a concave-convex shape is formed on the surface of the opposite surface member that does not face the substrate, so that the convex portion It is arranged in contact with the water-cooled wall surface, and the concave portion is used as a flow path of the temperature control gas of the opposite surface for flow control. Therefore, a gas-phase film-forming device will be provided, which utilizes a large-scale production device and controls the temperature of the opposite surface to a temperature suitable for the process with the characteristics of good uniformity and repeatability.

Hereinafter, the best embodiments for implementing the present invention will be described in detail based on the embodiments.

<Basic Concept> First, the basic concept of the present invention will be explained with reference to FIG. 1. FIG. 1 is a cross-sectional view showing the basic concept of the present invention. The basic structure of the present invention is a film-forming device based on a horizontal-type or self-rotating chemical vapor-phase film-forming device (Figure 1 is an example of a horizontal-type gas-phase film-forming device). That is to say, in the water-cooled chamber with the process gas introduction part and the exhaust part, a substrate 220, a carrier 222 for holding the substrate, a substrate 220 and a carrier 222 for heating Device, and is opposed to the substrate 220 and the carrier 222 to form an opposing surface member 20 of the film forming space. The flow direction of the process gas is in principle parallel to the substrate.

As described above, in the conventional technique, a gap (such as the gap 180 in FIG. 16 and the gap 280 in FIG. 18) is provided between the back surface of the opposed member and the chamber member. The temperature control gas circulates and performs temperature control, but conventionally, the back surface of the facing member is flat. On the contrary, in the present invention, a concave-convex shape 22 is provided on the rear surface (the chamber member 202 side) of the opposed member 20, and the convex portion 24 is brought into contact with the chamber member 220. Then, a mixed gas (contrast surface temperature control gas) composed of two kinds of gases with different thermal conductivity is circulated to the recess 26 to control the opposite surface temperature.

The lower limit of the control of the opposite surface temperature is obtained when the hydrogen with the best thermal conductivity (that is, 100% hydrogen) flows. In the present invention, the facing member 20 is partially brought into contact. Since the facing member 20 is a solid, it has a much higher thermal conductivity than hydrogen as a gas. In other words, the thermal conductivity is good. Since the facing member 20 having good thermal conductivity can be partially contacted with the chamber member 220, the effective heat conduction from the facing member 20 to the chamber member 20 is improved. Even if the height difference of the concave portion 26 as the non-contact portion becomes larger, it can be realized in the conventional method that it has the same effective thermal conductivity as the thermal conductivity when the width of the narrow gap is narrow. For calculation, in the present invention, the opposite surface temperature is about 200 to 250° C. under the film-forming conditions of nitrides, as long as the unevenness with a height difference of about 1 mm is formed. This will be explained in detail in the description of the simulation later. [Example 1]

<Application example of self-rotating vapor-phase film forming apparatus> First, the self-rotating vapor-phase film forming apparatus 10 will be described with reference to FIGS. 2 to 5. 2 is a cross-sectional view showing a self-rotating vapor-phase film forming apparatus. Fig. 3 is a plan view showing an example of the uneven shape of the facing member. FIG. 4 is a cross-sectional view of FIG. 3 taken along the line #A-#A and viewed from the direction of the arrow. Fig. 5 is a plan view showing another example of the uneven shape of the facing member.

First, the basic structure of the self-rotating vapor-phase film-forming apparatus 10 of this embodiment is the same as the above-mentioned conventional technique (refer to FIGS. 16 and 17). That is, as shown in FIG. 2, in the self-rotating vapor-phase film forming 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 part 106, a pair of surface temperature control gas introduction parts 150, a purge gas introduction part 160, and an exhaust part 108A, 108B. And, properly arranged in the chamber 110: a carrier 124 for placing the film-forming substrate 120 and the substrate holder 122; and an opposing member 20 having an opposing surface 21 opposed to the substrate 120 A film-forming space (fluid channel) 130 is formed between these bearing seats 124 and the facing member 126. The carrier 124 is provided as a mechanism that rotates around the rotating shaft 140, and the substrate holder 122 is provided as a mechanism that rotates around the center of the substrate 120.

In the present invention, in addition to the above structure, an uneven shape 22 is provided on the upper side of the facing member 20 (the chamber member 102 side). The opposing surface member 20 is provided so that the convex portion 24 of the concave-convex shape 22 contacts the water-cooled chamber member 102 to allow the opposing surface temperature control gas to flow into the concave portion 26.

As an example of the shape of the uneven shape 22, as shown in FIG. 3, a plurality of island-shaped (or dot-shaped) convex portions 24 are provided. FIG. 4 is a cross-sectional view of FIG. 3 taken along the line #A-#A and viewed from the direction of the arrow. The convex portion 24 and the concave portion 26 are arranged regularly. In addition, in FIG. 3, although the planar shape of the convex portion 24 is circular, even if it is, for example, a quadrangular shape, the effect is the same, so it can be any shape. In addition, regarding the arrangement of the convex portions 24, although a lattice-like periodic arrangement is adopted in FIG. 3, any arrangement may be adopted as long as the arrangement ensures temperature uniformity. In addition, even if it is not in an island shape, as shown in the facing member 20A of FIG. 5, it is possible to arrange the concave portion 26A whose width gradually increases from the middle opening portion 28 toward the outer edge in the radial direction. In this case, the convex portion 24A also has a radial shape.

<Application Example of Lateral Type Vapor-phase Film Formation Apparatus> Next, an application example of the lateral-type vapor-phase film formation apparatus 50 will be described with reference to FIGS. 6 to 8. 6 is a cross-sectional view showing a lateral-type vapor-phase film forming apparatus. 7 and 8 are diagrams showing an example of the uneven shape of the facing member. The basic structure of the lateral vapor-phase film forming apparatus 50 of this embodiment is the same as the above-mentioned conventional technology (as shown in FIGS. 18 and 19). That is, as shown in FIG. 6, on the lateral vapor-phase film forming 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 part 206, a pair of surface temperature control gas introduction parts 250, a purge gas introduction part 260, and an exhaust part 208. And, properly arranged in the chamber 210: a film-forming substrate 120 and a carrier 222 on which to mount it; and an opposing surface member 60 formed with an opposing surface 61 opposed to the substrate 220, etc. A film-forming space (fluid channel) 230 is formed between the carrier 222 and the facing member 226. In the structure of the above-mentioned horizontal-type vapor-phase film forming apparatus 200, only a mechanism for rotating the carrier 222 about the rotating shaft 240 is provided.

In the present invention, in addition to the above structure, an uneven shape 62 is provided on the upper side of the facing member 60 (the chamber member 202 side). The opposing surface member 60 is provided such that the convex portion 64 of the concave-convex shape 62 comes into contact with the water-cooled chamber member 202 to allow the opposing surface temperature control gas to flow to the concave portion 66. As a specific pattern of the concave-convex shape 62, for example, as shown in FIG. 7, the convex portion 64 has a shape in which lattices are periodically arranged. The cross section taken along line #B-#B as seen in the direction of the arrow in FIG. 7 is the same as in FIG. 4. In addition, as shown in the facing surface member 61A of FIG. 8, a plurality of convex portions 64A extending 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.

<Materials of each part> Next, the materials of each part will be described. It is also possible to use generally used stainless steel as an example of the chamber material, and if good thermal conductivity is required, materials such as aluminum can also be used. Carbon materials such as graphite are more suitable for the bearing seat or the substrate fixing seat. If the film formation object is nitrides and ammonia is used as the process gas, if carbon materials are used, they will be corroded by ammonia. In this case, it is better to use silicon carbide or boron nitride. , Carbon materials made of ammonia-resistant materials such as tantalum carbide. As the facing member, the same as the carrier, preferably coated with carbon material, or other materials as mentioned above, but other quartz, various ceramics, various metal materials, etc. as long as they are resistant to the process environment Can also be used.

<Simulation> An important design element in the implementation of the present invention is the area of the convex portion relative to the entire area of the area facing the substrate in the opposing surface member (hereinafter, simply referred to as "the whole") ) Area ratio and the height of the convex part (contact part). In addition, since the period of unevenness is related to the temperature distribution of the opposite surface, this is also one of the design parameters. The nature of these design parameters will be explained in detail in the following simulation examples.

As described above, the area ratio of the convex portion to the whole is important for the controllable temperature of the opposite surface temperature. The larger the area ratio of the convex portion, the lower limit of the control temperature becomes lower, and the controllable range becomes smaller. In addition, regarding the height of the convex portion, the lower the height, the lower the opposite surface temperature will be. Conversely, if the height is higher, the opposite surface temperature will become higher, so it can be used to obtain the desired The parameter of the surface temperature. Therefore, in this embodiment, a certain simulation model is set to change the area ratio of the convex portion and the height of the convex portion, and the influence of these parameters on the surface temperature is studied. In addition, the temperature distribution on the opposite surface (the side facing the carrier and the substrate) is formed by the uneven shape on the back surface of the opposite surface, so the temperature distribution on the opposite surface is also studied.

In this simulation, it is assumed that a groove-type unevenness is applied to the back surface of the opposite surface in a horizontal-type vapor-phase film forming apparatus as an embodiment of the present invention (a configuration similar to FIG. 8 ). 9(a) and (b) are explanatory diagrams showing areas for determining the execution of the simulation. Generally, a self-rotating vapor-phase film-forming device or a lateral vapor-phase film-forming device has a shape that expands in the horizontal direction, so the substantial heat conduction in the horizontal direction is almost negligible. Then, if the periodicity of the concave-convex shape is considered, it is enough to solve the two-dimensional model of the half-period perpendicular to the extending direction of the groove. In addition, if it is considered that substantial heat conduction in the horizontal direction can be ignored, it can be concluded that the conclusion of the model can also be applied to other embodiments. The area to which the simulation is applied (simulation area 68) is the area indicated by the thick broken line in FIG. 9(b).

FIG. 10 is a detailed cross-sectional view showing this simulation model. The size shown in the figure is the general size used in the actual MOCVD method. That is to say, the distance from the carrier or the substrate 220 to the opposed surface 61 (that is, the height of the film forming space) is 15 mm, and the total thickness of the opposed surface member 60A including the uneven structure is 10 mm. The thickness is 10 mm, and one side of the chamber member 220 is connected to the cooling water 240. Between the surface-facing member 60A and the surface of the chamber member 220, a thermal contact resistance is inevitably generated. The origin of the contact resistance is due to the tiny gap that must be generated between the two contacting objects. Therefore, in this simulation, there is a gap of 0.1 mm between the facing member 60A and the chamber member 220. This is considered a reasonable number in experience. In addition, the contact resistance can actually be adjusted to some extent by the surface roughness of the member or the like.

The physical property values of each part of the model will be set as follows based on the physical properties of various materials generally revealed. (1) The emissivity from the carrier (substrate 220), assuming a carbon-based material, is set to 0.85. (2) As the thermal conductivity of the film-forming space, it is assumed that hydrogen is the most commonly used carrier gas, and it is 0.235 W/m/s. (3) Assume that the facing member is a 60A carbon-based material, and has an emissivity of 0.85 and a thermal conductivity of 100 W/m/s. (4) Two regions of hydrogen and nitrogen were modeled for the area where the gas flow was controlled by the surface temperature (recess 66A), and the thermal conductivity coefficients were set to 0.225 and 0.034, respectively. (5) The chamber member 220 is assumed to be stainless steel, and has an emissivity of 0.4 and a thermal conductivity of 17 W/m/s. (6) Regarding the temperature boundary conditions, the surface of the high-temperature-side carrier (substrate 220) is set to 1000°C, and the interface between the low-temperature-side chamber member 102 and the cooling water 204 is set to 40°C.

In the above physical properties, for example, even if a part of the carbon-based member is coated with another material, since the thickness of the coating is thin, it can be assumed that the thermal conductivity is the same as that of the carbon material. In addition, regarding the emissivity, the silicon carbide coating is almost the same as the carbon material. If the thickness of the boron nitride coating is also very small, it is not much different from the emissivity of carbon. In other words, in the case where these materials are used, in fact, it is considered that almost the same results as the simulation can be obtained.

Using the above model and physical property values, a variety of uneven surface area ratios and uneven heights were simulated. In this simulation, the opposing surface member 60A of the opaque body and the inside of the chamber member 2202 only deal with heat conduction and are filled with a film-forming space of gas as a transparent body; and the gap between the surface-facing member 60A and the chamber member 220 except In addition to the heat conduction of the gas, the heat transfer due to radiation is also considered.

FIG. 11 shows an example of the temperature distribution of the portion from the heater to the cooling water obtained by the simulation results. In addition, for the sake of clarity, it is displayed at two different temperature display ratios in two ways. In this example, the result is calculated under the condition that the area ratio of the convex portion is 0.5, the height of the convex portion is 1 mm, and the temperature of the opposite surface temperature control gas is 100% hydrogen. The same simulation was performed for each condition, and from the obtained results, the effects of the area ratio of the convex portion and the height of the convex portion on the surface temperature of the opposite surface are summarized in FIGS. 12 to 15. In these figures, the abscissa represents the area ratio of the convex portion (contact portion) to the entire area (hereinafter, referred to as "convex area ratio").

12 is a graph showing the relationship between the area of the convex portion and the overall area and the temperature (° C.) (vertical axis) of the opposing surface. In this figure, the opposite surface temperature of both the opposite surface temperature control gases H ₂ and N ₂ is shown. According to FIG. 12, as expected, the smaller the area ratio of the contact portion, the higher the temperature of the opposite surface. That is to say, by appropriately selecting the area ratio, an arbitrary control temperature range of the opposite surface temperature can be obtained. The temperature is set to 200 to 250°C, and the area ratio of the convex portion is preferably 0.3 to 0.6.

13 is a graph showing the relationship between the area ratio of the convex portion and the temperature control width (° C.) (vertical axis) of the opposing surface. According to this figure, the smaller the area ratio, the larger the control width, which is optimal. In fact, which area ratio to use must consider both the temperature range and the control width to determine the minimum area ratio. In addition, it can be found from FIG. 13 that the height dependence of the convex portion is small in the control width. In other words, it can be understood that even if the height of the convex portion is increased, the control of the width cannot be so beneficial.

14 and 15 are diagrams showing the relationship between the area ratio of the convex portion and the size (°C) (vertical axis) of the temperature distribution on the surface of the opposing surface. Fig. 14 shows the difference between the maximum temperature and the minimum temperature of the opposite surface temperature when the opposite surface control gas is hydrogen, and Fig. 15 shows the maximum temperature and the opposite temperature of the opposite surface temperature when the opposite surface control gas is nitrogen The difference between the minimum temperature. Of course, the temperature near the convex portion (contact portion) is low, and the temperature of the concave portion is high. Accordingly, the higher the height of the convex portion, the greater the temperature difference of the opposite surface. In other words, when the height of the convex portion is high, it can be understood that the control width does not change so much, and the temperature distribution of the opposite surface surface also deteriorates, so it is best not to increase the height of the convex portion too much. Judging from FIGS. 14 and 15, it is considered that the height of the convex portion is 2 mm or less. From the viewpoint of processing accuracy, the height of the convex portion is as large as possible, but when it is 2 mm or more, the adverse effect of the deterioration of the surface temperature distribution cannot be ignored.

As described above, in the case of a nitride film-forming process, the opposite surface temperature is preferably 200 to 250°C. In order to satisfy this condition, as can be seen from FIGS. 12 to 15, the area ratio of the contact portion (convex portion) is 0.3 to 0.6, and the height of the convex portion is preferably 2 mm or less. The optimal values of the area ratio of the convex portion and the height of the convex portion vary depending on the type of film to be formed, the material used as the facing member, or the film forming conditions, but in most cases, it is considered to be set at the above Within the scope is more appropriate.

As described above, according to the first embodiment, the following effects will be obtained. That is, in the conventional method, it is necessary to uniformly realize a narrow gap width of about 0.1 to 0.2 mm over a large area, so precise machining accuracy is required. In contrast, in the present invention, as long as a relatively large difference in height is about 2 mm, it is sufficient to greatly reduce the difficulty of processing. Therefore, it is possible to obtain good uniformity of the opposing surface temperature over a large area at low cost. In addition, unlike the conventional method, the contact area with the chamber wall is large, so the repeatability and stability of the installation are increased. As described above, according to this embodiment, even for a large-area facing surface, a facing surface temperature of about 200 to 250° C. can be achieved to achieve good uniformity and good repeatability.

In addition, the present invention is not limited to the above-mentioned embodiment, and various modifications can be made within a range not departing from the gist of the present invention. For example, it also contains the following content. (1) The shapes and sizes shown in the above embodiments are only examples, and can be appropriately changed according to needs. (2) In the above embodiments, although the self-rotating vapor-phase film-forming apparatus and the lateral-type vapor-phase film-forming apparatus are taken as examples for description, the present invention is also applicable to fluids formed in a horizontal direction (film-forming space) The whole reactor of the channel. (3) The material or process gas of each part shown in the above-mentioned embodiments, the counter surface temperature control gas or the purge gas are only examples, and can be appropriately changed within the range that produces the same effect. (4) The concave-convex shape shown in the above embodiment is only an example, and can be appropriately changed within a range that produces the same effect. [Industry availability]

If the gas-phase film forming apparatus according to the present invention is provided with: a susceptor having a material gas introduction part and an exhaust part, and having a space in the chamber surrounded by the water-cooled wall surface Holding a film-forming substrate; and a pair of facing members formed with a horizontal flow channel (Flow channel) relative to the carrier and the film-forming substrate; wherein, in the chamber, a pair of facing temperatures are provided The control gas introduction part introduces the opposite surface temperature control gas for controlling the temperature of the opposite surface member, and at the same time, a concave-convex shape is formed on the surface of the opposite surface member that does not face the substrate The convex portion is arranged in contact with the water-cooled wall surface, and the concave portion is used as a flow path of the temperature control gas of the opposite surface for flow control. Therefore, since the temperature of the opposite surface can be controlled to a temperature suitable for a process with good uniformity and repeatability, it can be applied to the use of the vapor-phase film forming apparatus. Especially suitable for large-scale production equipment.

10‧‧‧Self-rotating vapor-phase film-forming device 20, 20A‧‧‧ Opposite surface member 21‧‧‧ Opposite surface 22‧‧‧Convex and concave shape 24, 24A‧‧‧Convex part (contact part) 26, 26A‧ ‧‧Concave part (temperature-controlled gas flow path) 28‧‧‧Opening part 50‧‧‧Transverse chamber vapor-phase film forming device 60, 60A ‧‧‧ Opposite surface member 61‧‧‧ Opposite surface 62‧‧‧Convex and concave shape 64, 64A ‧‧‧ convex part 66, 66A ‧‧‧ concave part 68 ‧ ‧ ‧ simulation area 100 ‧ ‧ ‧ self-rotating gas-phase film forming device 102 ‧ ‧ ‧ chamber member 104 ‧ ‧ ‧ cooling water 106 ‧ ‧ ‧ Gas introduction part 108A, 108B ‧‧‧ exhaust part 110 ‧ ‧ ‧ chamber 120 ‧ ‧ ‧ substrate (substrate for film formation) 122 ‧ ‧ ‧ substrate fixing seat 124 ‧ ‧ ‧ carrier 126 ‧ ‧ ‧ facing member 128‧‧‧ opposite surface 130‧‧‧ film-forming space (fluid channel) 140‧‧‧rotating shaft 150‧‧‧ opposite surface temperature control gas introduction part 160‧‧‧ purge gas introduction part 170‧‧‧ heater 180‧‧‧Gap 200‧‧‧Horizontal gas-phase film-forming device 202‧‧‧ Chamber member 204‧‧‧‧Cooling water 206‧‧‧ Process gas introduction part 208‧‧‧Exhaust part 210‧‧‧ Chamber 220‧‧‧Film-forming substrate 222‧‧‧Carrier 226‧‧‧ Opposite surface member 228‧‧‧ Opposite surface 230‧‧‧ Film-forming space (fluid channel) 240‧‧‧Rotating shaft 250‧‧‧ pairs Air temperature control gas introduction part 260‧‧‧Purge gas introduction part 270‧‧‧ Heater 280‧‧‧Gap

FIG. 1 is a cross-sectional view showing the basic concept of the present invention. 2 is a cross-sectional view showing a self-rotating vapor-phase film forming apparatus according to Embodiment 1 of the present invention. FIG. 3 is a plan view showing an example of the uneven shape of the facing member in Embodiment 1 of the present invention. FIG. 4 is a cross-sectional view of FIG. 3 taken along the line #A-#A and viewed from the direction of the arrow. Fig. 5 is a plan view showing another example of the concave-convex shape of the facing member according to the first embodiment of the present invention. 6 is a cross-sectional view showing a lateral-type vapor-phase film forming apparatus according to Embodiment 2 of the present invention. 7 is a plan view showing an example of the concave-convex shape of the facing member in Embodiment 2 of the present invention. FIG. 8 is a plan view showing another example of the concave-convex shape of the facing member according to the second embodiment of the present invention. FIG. 9 is an explanatory diagram showing an area for determining the execution of the simulation in the present invention. 10 is a cross-sectional view showing a simulation model of the present invention. FIG. 11 is a diagram showing an example of a two-dimensional temperature distribution map in the simulation model. FIG. 12 is a graph showing the relationship between the area ratio of the convex portion (contact portion) and the overall area and the temperature of the opposing surface in the simulation. FIG. 13 is a graph showing the relationship between the area ratio of the convex portion (contact portion) and the overall area and temperature control width of the opposing surface in the simulation. FIG. 14 is a graph showing the relationship between the area ratio of the convex portion (contact portion) and the total area in the simulation and the size of the subsurface temperature division (control gas: hydrogen). FIG. 15 is a graph showing the relationship between the area ratio of the convex portion (contact portion) and the overall area and the size of the subsurface temperature division (control gas: nitrogen) in the simulation. 16 is a cross-sectional view showing a general self-rotating vapor-phase film forming apparatus. FIG. 17 is a plan view showing a carrier of the self-rotating vapor-phase film forming apparatus of FIG. 16. Fig. 18 is a cross-sectional view showing a general lateral vapor-phase film forming apparatus. Fig. 19 is a plan view showing a carrier of the lateral vapor-phase film forming apparatus of Fig. 18; FIG. 20 is a cross-sectional view showing the heat flow of a conventional gas-phase film forming apparatus. 21 is a graph showing the relationship between the width of the gap between the chamber member and the opposed surface and the lower and upper limit values of the temperature of the opposed surface in the conventional gas-phase film forming apparatus.

20‧‧‧opposite member

22‧‧‧Bump shape

24‧‧‧Convex

26‧‧‧recess

202‧‧‧chamber components

204‧‧‧cooling water

220‧‧‧Film forming substrate

222‧‧‧Carrying seat

Claims (7)

A gas-phase film-forming device is equipped with a susceptor, which has a material gas introduction part and an exhaust part, and has a chamber space surrounded by a water-cooled wall surface for holding a film A substrate; and a pair of facing members formed with a horizontal flow channel (Flow channel) relative to the carrier and the film-forming substrate; wherein, in the chamber, a pair of facing temperature control gases are introduced Part, which introduces the opposite surface temperature control gas for controlling the temperature of the opposite surface member, and at the same time forms a concave-convex shape on the surface of the opposite surface member that does not face the substrate to allow the convex portion to be arranged It is in contact with the water-cooled wall surface, and the concave portion is used as a flow path of the temperature control gas of the opposite surface for flow control. The gas-phase film-forming device as described in item 1 of the patent application range, wherein the opposite-surface temperature control gas system is composed of a mixed gas composed of two or more gases having different thermal conductivity coefficients. The gas-phase film-forming device as described in item 2 of the patent application range, wherein the opposite-side temperature control gas system is composed of hydrogen and nitrogen. The vapor-phase film-forming apparatus according to any one of the patent application scopes 1 to 3, wherein the area of the contact portion with the convex portion in the area in the area facing the substrate of the opposed surface member The total area of this area is 0.3 to 0.6. The vapor-phase film-forming apparatus according to any one of the patent application scopes 1 to 3, wherein the height of the convex portion is 2 mm or less. The vapor-phase film-forming apparatus according to any one of the patent application scopes 1 to 3, wherein a film-forming object is formed on the substrate by an organometallic vapor phase film formation method. The vapor-phase film-forming device as described in item 6 of the patent application range, wherein the object to be formed on the substrate is a nitride-based compound semiconductor.

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