Film forming apparatus

Abstract

A film forming apparatus (100) is provided with a chamber (1), a mounting table (21), and a fluid head (3). The fluid head (3) is provided inside the chamber (1) at a position facing the first main surface of the substrate (W) placed on the placement table (21). The fluid head (3) has a plasma chamber (4b), a plasma source (5), a plurality of first outlets (4c), a gas flow path (6b), and a plurality of second outlets (6c). A plasma source (5) converts a first raw material gas into plasma in a plasma chamber (4b). The first outflow ports (4c) are two-dimensionally dispersed and arranged in an overlapping region that overlaps the first main surface of the substrate (W) in plan view. Active species derived from the first raw material gas flow out from the first outlet (4c) toward the first main surface of the substrate (W). The plurality of second outlets (6c) are two-dimensionally dispersed and arranged at positions different from those of the plurality of first outlets (4c) in the overlapping region. The second source gas flows out from the plurality of second outlets (6c) toward the first main surface of the substrate (W).

Description

Technical Field

[0001] The present disclosure relates to a film forming device. Background Art

[0002] In the past, an organic metal vapor phase growth method using plasma has been proposed (for example, Patent Document 1). In the manufacturing device described in Patent Document 1, a mixed gas of nitrogen (N2) gas and hydrogen (H2) gas is converted into plasma in a furnace body, while an organic metal gas of a group III element is supplied into the furnace body. Thus, a group III nitride semiconductor film can be formed on a substrate at a relatively low temperature.

[0003] In this manufacturing device, a susceptor for supporting a substrate is provided at the lower part of the furnace body. A shower head electrode is provided at the upper part of the furnace body. The mixed gas is plasmatized by passing through the shower head electrode downward, and the active species generated by the plasma are supplied to the substrate. A gas supply pipe for allowing the organic metal gas to flow out is also provided in the furnace body. The gas supply pipe is provided at a height position between the susceptor and the shower head electrode, and includes a ring portion surrounding the susceptor. A plurality of nozzles are formed on the inner side of the ring portion, and the organic metal gas is ejected from the nozzles to the inner side of the ring portion and supplied to the substrate.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent No. 6516482 Summary of the invention

[0007] Problem that the invention aims to solve

[0008] However, in the technique described in Patent Document 1, since the organic metal gas flows from the outer periphery to the inner side of the substrate, the concentration of the organic metal gas tends to be high at the outer periphery of the substrate and low at the center, making it difficult to control the film thickness to be uniform.

[0009] Therefore, an object of the present disclosure is to provide a film forming apparatus capable of forming a target film on a substrate with a more uniform film thickness.

[0010] Means used to solve problems

[0011] The first mode is a film forming device, which comprises: a chamber, a mounting table arranged in the chamber, a substrate being mounted thereon, and a fluid head arranged in the chamber at a position facing the first main surface of the substrate mounted on the mounting table; the fluid head includes: one or more first inlet ports, a plasma chamber, through which a first raw material gas flows in; a plasma source, which plasmatizes the first raw material gas in the plasma chamber, a plurality of first outlet ports, which are connected to the plasma chamber and are two-dimensionally dispersedly arranged in an overlapping area overlapping with the first main surface of the substrate when viewed from above, so that active species generated by the plasmatization of the first raw material gas flow out toward the first main surface of the substrate; one or more second inlet ports, a gas flow path, through which a second raw material gas flows in, and which is separated from the plasma chamber, and a plurality of second outlet ports, which are connected to the gas flow path and are two-dimensionally dispersedly arranged in the overlapping area at positions different from the plurality of first outlet ports, so that the second raw material gas flows out toward the first main surface of the substrate.

[0012] The second method is that, in the film forming device of the first method, there is also a heater, and the heater heats the substrate from the second main surface side of the substrate, and the gas flow path has: a flow path space, which is located on the side opposite to the mounting table relative to the plasma chamber, for the second raw material gas to flow in through the second inlet, and a plurality of through flow paths, which extend from the flow path space and penetrate the plasma chamber; and a plurality of the second outflow ports are respectively formed at the front ends of the plurality of through flow paths.

[0013] In a third aspect, in the film forming apparatus of the second aspect, at least a portion of the plasma source is provided between the flow path space and the plasma chamber and penetrated by the plurality of the through flow paths.

[0014] A fourth aspect is that, in the film forming apparatus of the third aspect, the plasma source is a surface wave plasma source or a hollow cathode discharge plasma source.

[0015] A fifth aspect is that, in the film forming apparatus of the third or fourth aspect, the fluid head further includes a cooling unit that cools the plasma source, and the cooling unit is provided between the flow path space and the plasma source and penetrated by the plurality of through flow paths.

[0016] According to a sixth aspect, in the film forming apparatus of any one of the second to fifth aspects, the fluid head includes a conductive shield provided between each of the plurality of through-flow channels and the plasma chamber.

[0017] According to a seventh aspect, in the film forming apparatus of any one of the second to sixth aspects, an opening area of ​​each of the plurality of second outlets is smaller than a flow path area of ​​each of the plurality of through flow paths.

[0018] According to an eighth aspect, in the film forming apparatus of any one of the second to seventh aspects, the plurality of second outflow ports are located on the mounting table side relative to the plurality of first outflow ports.

[0019] A ninth aspect is that, in a film forming device of any one of the first to eighth aspects, the first inlet is formed on a side of the plasma chamber, and among a plurality of the first outlets, an opening ratio of the first outlets in a central area located in the overlapping area is greater than an opening ratio of the first outlets in a peripheral area located in the overlapping area closer to the outside than the central area.

[0020] The tenth embodiment is that, in a film forming device of any one of the first to ninth embodiments, the second inlet is formed on the side of the gas flow path, and among the multiple second outflow outlets, the opening ratio of the second outflow outlet in the central area located in the overlapping area is greater than the opening ratio of the second outflow outlet in the peripheral area located in the overlapping area closer to the outside than the central area.

[0021] An eleventh aspect is the film forming apparatus according to any one of the first to tenth aspects, wherein the second inlet is formed above a central portion of the gas flow path.

[0022] The twelfth method is that, in a film forming device of any one of the first to eleventh methods, there is: a first gas supply unit for supplying the first raw material gas to the fluid head, and a second gas supply unit for supplying the second raw material gas and an inactive carrier gas for conveying the second raw material gas to the fluid head; the second gas supply unit does not supply the second raw material gas but supplies the carrier gas to the fluid head during a specified period starting from the time point when the first gas supply unit supplies the first raw gas and the plasma source is operated, and supplies the second raw material gas and the carrier gas to the fluid head after the specified period.

[0023] A thirteenth aspect is that in the film forming apparatus of any one of the first to twelfth aspects, the first source gas includes a gas containing a Group 15 element, and the second source gas includes an organic metal gas containing a Group 13 element.

[0024] Effects of the Invention

[0025] According to the first method, active species originating from the first raw material gas flow out to the first main surface of the substrate from a plurality of first outflow ports two-dimensionally dispersedly arranged in an overlapping region overlapping with the first main surface of the substrate. Therefore, the active species are more evenly supplied to the first main surface of the substrate. The second raw material gas flows out to the first main surface of the substrate from a plurality of second outflow ports two-dimensionally dispersedly arranged in a position different from the first outflow port in an overlapping region overlapping with the first main surface of the substrate. Therefore, the second raw material gas is also more evenly supplied to the first main surface of the substrate. Therefore, the object film obtained by the reaction of the active species and the second raw material gas can be more evenly formed on the first main surface of the substrate.

[0026] According to the second embodiment, the flow path space is located on the side opposite to the mounting table relative to the plasma chamber. Therefore, the flow path space is arranged at a position away from the heater. Therefore, the possibility of thermal decomposition of the second raw material gas in the flow path space can be reduced. Furthermore, the precipitation of various components of the second raw material gas on the inner wall of the flow path space (i.e., the inner peripheral surface forming the flow path space) due to the thermal decomposition of the second raw material gas can be suppressed.

[0027] In other words, the plasma chamber is disposed closer to the substrate. Therefore, more active species in the plasma chamber reach the first main surface of the substrate before being deactivated. Therefore, the target film can be formed on the first main surface of the substrate with higher efficiency.

[0028] According to the third aspect and the fourth aspect, plasma can be generated in the plasma chamber over a larger area than the substrate.

[0029] According to the fifth aspect, since the cooling unit is close to the plasma source, the plasma source can be effectively cooled. In addition, the heat transfer from the plasma source to the flow path space can be suppressed by the cooling unit. Therefore, the possibility of thermal decomposition of the second raw material gas in the flow path space can be reduced.

[0030] According to the sixth aspect, since the generation of an electric field for plasma in the through-flow channel can be suppressed, it is possible to suppress application of an unnecessary electric field to the second source gas.

[0031] According to the seventh and eighth aspects, the distance between the second outlet and the first outlet can be extended. Therefore, the possibility of the active species flowing out of the first outlet reaching the second outlet can be reduced. Therefore, the reaction between the active species and the second raw material gas near the second outlet can be suppressed, and the formation of an unnecessary compound film on the inner peripheral surface forming the second outlet can be suppressed.

[0032] According to the ninth aspect, the active species can be made to flow out from the plurality of first outlets more uniformly.

[0033] According to the tenth aspect and the eleventh aspect, the second source gas can be made to flow out from the plurality of second outlets more uniformly.

[0034] According to the twelfth method, during a specified period at the initial stage of the operation of the plasma source, the second raw material gas does not flow out from the second outlet, and the carrier gas flows out from the second outlet. Although the plasma is unstable during the specified period, the second raw material gas does not flow out from the second outlet, so the film forming process does not start. Therefore, it is possible to suppress the uneven formation of the object film on the first main surface of the substrate. In addition, since the carrier gas flows out from the second outlet, the active species flowing out from the first outlet hardly flow into the second outlet. Therefore, even if the second gas supply unit supplies the second raw material gas to the fluid head after the specified period, the reaction between the second raw material gas and the active species hardly occurs in the gas flow path. Therefore, it is possible to suppress the formation of an unnecessary compound film on the inner peripheral surface of the gas flow path.

[0035] According to the thirteenth aspect, the III-V compound semiconductor can be formed more uniformly on the first main surface of the substrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 This is a diagram schematically showing an example of the structure of the film forming apparatus according to the first embodiment.

[0037] Figure 2 This is a cross-sectional view schematically showing an example of the structure of the fluid head according to the first embodiment.

[0038] Figure 3 This is a cross-sectional view schematically showing an example of the structure of a fluid head.

[0039] Figure 4 is an exploded cross-sectional view showing one example of the structure of a fluid head.

[0040] Figure 5 This is a cross-sectional view schematically showing an example of the structure of a plasma source.

[0041] Figure 6 This is a cross-sectional view schematically showing an example of the structure of a plasma source.

[0042] Figure 7 This is a block diagram schematically showing an example of the configuration of the control unit.

[0043] Figure 8 This is a diagram schematically showing another example of the fluid head according to the first embodiment.

[0044] Fig. 9 Yes Figure 8 FIG. 1 is a diagram showing the various structures of a fluid head in an exploded and schematic manner.

[0045] Fig.10 It is schematically shown Fig. 9 Diagram of the XX section.

[0046] Fig.11 It is schematically shown Figure 8 Figure XI-XI section of FIG.

[0047] Fig.12 This is a cross-sectional view schematically showing an example of the structure of the fluid head according to the second embodiment.

[0048] Fig.13 This is a cross-sectional view schematically showing an example of the structure of the cooling unit.

[0049] Fig.14 This is a cross-sectional view schematically showing an example of the structure of the second flow path member of the fluid head according to the third embodiment.

[0050] Fig.15 This is a cross-sectional view schematically showing another example of the structure of the second flow path member of the fluid head according to the third embodiment.

[0051] Fig.16 This is a cross-sectional view schematically showing an example of the structure of a fluid head according to the third embodiment.

[0052] Fig.17 This is a cross-sectional view schematically showing an example of the structure of the first flow path member of the fluid head according to the third embodiment.

[0053] Fig.18 This is a diagram schematically showing an example of the structure of the second gas supply unit according to the fourth embodiment.

[0054] Fig.19 This is a flowchart showing an example of the operation of the film forming apparatus according to the fourth embodiment. DETAILED DESCRIPTION

[0055] Below, while referring to the attached Figure 1 The embodiments are described below. In addition, the drawings are schematically shown, and for the convenience of description, the structure is appropriately omitted or simplified. In addition, the size and position of the structure shown in the drawings are not necessarily accurately described, and can be appropriately changed.

[0056] In the following description, the same components are denoted by the same reference numerals, and their names and functions are also the same, so their detailed description may be omitted to avoid duplication.

[0057] In the following description, even if ordinal numbers such as "first" or "second" are used, these terms are used for convenience in order to facilitate understanding of the contents of the embodiments, and are not limited to the order that may be generated by these ordinal numbers.

[0058] In the case of using expressions indicating relative or absolute positional relationships (e.g., "towards a direction," "along a direction," "parallel," "orthogonal," "center," "concentric," "coaxial," etc.), if there is no special explanation, the expression is set to not only strictly indicate the positional relationship, but also indicate the state of relative displacement in angle or distance within the tolerance or the range of obtaining the same degree of function. In the case of using expressions indicating equal states (e.g., "same," "equal," "homogeneous," etc.), if there is no special explanation, the expression is set to not only indicate the state of strictly equal quantitatively, but also indicate the state of difference in the presence of tolerance or the same degree of function. In the case of using expressions indicating shapes (e.g., "quadrilateral" or "cylindrical," etc.), if there is no special explanation, the expression is set to not only strictly indicate the shape geometrically, but also indicate the shape, such as concave-convex or chamfered, within the range of obtaining the same degree of effect. In the case of using expressions of "setting," "preparing," "equipped," "including," or "having" one constituent element, the expression is not an exclusive expression that excludes the existence of other constituent elements. When the expression "at least any one of A, B, and C" is used, the expression includes only A, only B, only C, any two of A, B, and C, and all of A, B, and C.

[0059] <First embodiment>

[0060] <Overview of film forming equipment>

[0061] Figure 1 1 is a diagram schematically showing an example of the structure of the film forming apparatus 100 of the first embodiment. The film forming apparatus 100 is an apparatus for forming a target film on a substrate W by a gas phase growth method using plasma. The target film is a film containing a compound, for example, a III-V compound semiconductor film containing a Group 13 element (hereinafter referred to as a Group III element) and a Group 15 element (hereinafter referred to as a Group V element). When nitrogen is used as the Group V element, the compound semiconductor can be called a Group III nitride semiconductor. Group III nitride semiconductors are used, for example, in horizontal transistors.

[0062] The substrate W is, for example, in the form of a plate. The substrate W is, for example, a substrate of sapphire, silicon carbide, or silicon. The substrate W is, for example, in the form of a circular plate. The substrate W has a first principal surface and a second principal surface on the opposite side of the first principal surface. Here, the first principal surface is the upper surface of the substrate W, and the second principal surface is the lower surface of the substrate W. Since the compound semiconductor film is crystallized and grown on the first principal surface of the substrate W, the substrate W can also be referred to as a growth substrate. In addition, the material and shape of the substrate W are not limited thereto and can be appropriately changed.

[0063] like Figure 1 As shown, the film forming apparatus 100 includes a chamber 1, a substrate holding unit 2, a fluid head 3, and a control unit 9. Hereinafter, each structure will be summarized, and then a specific example thereof will be described in detail.

[0064] The chamber 1 has a box-shaped hollow shape. The internal space of the chamber 1 corresponds to a processing space for film forming on the substrate W. The chamber 1 may also be referred to as a vacuum chamber. On the side wall of the chamber 1, a gate or a gate valve (not shown) for carrying in and out the substrate W may also be provided.

[0065] The substrate holding unit 2 is provided in the chamber 1. The substrate holding unit 2 includes a susceptor 21 as a mounting table for mounting the substrate W. The substrate W is mounted on the susceptor 21 in a horizontal posture. The horizontal posture here means a posture in which the thickness direction of the substrate W is along the vertical direction.

[0066] exist Figure 1 In the example of FIG. 1 , the film forming apparatus 100 is further provided with a suction unit 7. The suction unit 7 sucks gas in the chamber 1 to reduce the pressure in the chamber 1. The suction unit 7 adjusts the pressure in the chamber 1 to a predetermined reduced pressure range suitable for film forming processing.

[0067] exist Figure 1 In the example of , a heater 8 is further provided in the film forming apparatus 100. The heater 8 is provided in the chamber 1 and heats the substrate W. Specifically, the heater 8 heats the substrate W so that the temperature of the substrate W is within a temperature range suitable for the film forming process. Figure 1 In the example of FIG. 5 , the heater 8 heats the substrate W from the second main surface (here, the lower surface) side of the substrate W.

[0068] The fluid head 3 is disposed in the chamber 1 at a position facing the first main surface (here, the upper surface) of the substrate W on the susceptor 21. Here, the fluid head 3 is disposed just above the substrate W on the susceptor 21. The fluid head 3 causes the active species obtained by converting the first raw material gas into plasma to flow toward the first main surface of the substrate W, and causes the second raw material gas to flow toward the first main surface of the substrate W.

[0069] The first raw material gas contains, for example, a group V gas containing a group V element. The group V element is, for example, nitrogen. In this case, nitrogen can be used as the group V gas. In addition to nitrogen, the first raw material gas may also contain hydrogen. That is, the first raw material gas may also be a mixed gas of a group V gas and hydrogen. When the first raw material gas is a mixed gas of nitrogen and hydrogen, active species such as nitrogen radicals and hydrogen radicals are generated by plasma formation.

[0070] The second source gas contains, for example, an organic metal gas containing a Group III element. The Group III element is, for example, gallium. In this case, as the organic metal gas, TMGa (trimethylgallium), TEGa (triethylgallium), or TDMAGa (tris dimethylamidogallium) can be used.

[0071] When the active species from the first source gas and the second source gas are supplied to the first main surface of the substrate W, they react with each other to form a target film on the first main surface of the substrate W. For example, a group III nitride semiconductor film is formed as the target film.

[0072] Figure 2 and Figure 3 It is a cross-sectional view schematically showing an example of the structure of the fluid head 3 . Figure 2 Show Figure 1 Section II-II, Figure 3 Show Figure 1 Section III-III of the diagram.

[0073] like Figures 1 to 3 As shown, the fluid head 3 includes a first inlet 4a, a plasma chamber 4b, a plurality of first outlets 4c, a plasma source 5, a second inlet 6a, a gas flow path 6b, and a plurality of second outlets 6c.

[0074] As described in detail later, the first raw material gas flows into the plasma chamber 4b through the first inlet 4a, and the second raw material gas flows into the gas flow path 6b through the second inlet 6a. The plasma chamber 4b and the gas flow path 6b are separated from each other inside the fluid head 3. That is, the plasma chamber 4b and the gas flow path 6b are not connected to each other inside the fluid head 3.

[0075] exist Figure 1 and Figure 2 In the example of , the plasma chamber 4b is a flat space whose vertical dimension is smaller than its horizontal dimension. Figure 1 and Figure 2 In the example of FIG. 4 , the first inlet 4a is formed at a side of the plasma chamber 4b. The first inlet 4a is connected to the first gas supply unit 40. The first gas supply unit 40 supplies the first raw material gas to the plasma chamber 4b through the first inlet 4a.

[0076] The plurality of first outlets 4c are connected to the plasma chamber 4b. Specifically, the plurality of first outlets 4c are formed in the lower part of the plasma chamber 4b. When viewed from above, the plurality of first outlets 4c are two-dimensionally dispersed in the overlapping region R0 overlapping with the first main surface of the substrate W (see also FIG. Figure 2 ). In addition, Figure 2 and Figure 3 In FIG. 1 , the outline of the substrate W when viewed from above is shown by an imaginary line. Figure 2 In the example, the plurality of first outlets 4c are arranged in a matrix. The plurality of first outlets 4c may also be dispersedly arranged in a large part of the overlapping region R0. As a more specific example, the plurality of first outlets 4c may be dispersedly arranged in a circular region having a diameter greater than half of the diameter of the substrate W and being concentric with the substrate W. Figure 2 In the example of FIG. 1 , each first outflow port 4 c has a circular shape in a plan view.

[0077] The plasma source 5 excites the first raw material gas into plasma in the plasma chamber 4b. In other words, the plasma source 5 converts the first raw material gas into plasma. Figure 1 In the example of , the plasma source 5 is arranged on the side opposite to the susceptor 21 with respect to the plasma chamber 4b. Here, the plasma source 5 is arranged vertically above the plasma chamber 4b. The plasma source 5 generates an electric field for plasma in the plasma chamber 4b. The first raw material gas passes through the electric field, and the electric field acts on the first raw material gas, so that the first raw material gas is plasmatized. As a result, active species such as highly reactive ions or neutral radicals are generated in the plasma chamber 4b.

[0078] When the first source gas contains hydrogen and nitrogen, hydrogen radicals and nitrogen radicals are generated as active species. These active species flow out from the plurality of first outlets 4c. The active species from the first outlets 4c flow toward the first main surface of the substrate W.

[0079] The second raw material gas flows into the gas flow path 6b through the second inlet 6a. Figure 1 and Figure 3 In the example of FIG. 1 , the second inlet 6a is formed at a side of the gas flow path 6b. The second inlet 6a is connected to the second gas supply unit 50. The second gas supply unit 50 supplies the second raw material gas to the gas flow path 6b through the second inlet 6a.

[0080] exist Figure 1 and Figure 3In the example of , the gas flow path 6b has a flow path space 6b1 and a plurality of through flow paths 6b2. The flow path space 6b1 is located on the side opposite to the susceptor 21 with respect to both the plasma chamber 4b and the plasma source 5. Here, the flow path space 6b1 is located vertically above the plasma source 5. In other words, the plasma source 5 is provided between the flow path space 6b1 and the plasma chamber 4b.

[0081] exist Figure 1 and Figure 3 In the example of , the flow path space 6b1 is a flat space whose dimension in the vertical direction is smaller than that in the horizontal direction. Figure 1 and Figure 3 In the example of FIG. 6 , the second inlet 6 a is formed on the side of the flow path space 6 b 1 .

[0082] A plurality of through-flow passages 6b2 extend from the flow passage space 6b1, and penetrate the plasma source 5 and the plasma chamber 4b. Here, the through-flow passages 6b2 extend vertically downward from the flow passage space 6b1. A second outlet 6c is formed at the front end (here, the lower end) of each through-flow passage 6b2.

[0083] The plurality of second outlets 6c are connected to the gas flow path 6b and are two-dimensionally dispersedly arranged at positions different from the plurality of first outlets 4c in the overlapping region R0 overlapping the first main surface of the substrate W when viewed from above. The plurality of second outlets 6c are two-dimensionally arranged in a plan view, for example, in a matrix shape (see also Figure 2 and Figure 3 ). The plurality of second outlets 6c may also be dispersedly arranged in most of the overlapping region R0. As a more specific example, the plurality of second outlets 6c may be dispersedly arranged in a circular region having a diameter greater than one-half of the diameter of the substrate W and being concentric with the substrate W. Figure 2 and Figure 3 In the example of FIG. 1 , each second outflow port 6 c has a circular shape in a plan view.

[0084] The second source gas that has flowed into the gas flow path 6 b through the second inlet 6 a flows toward the plurality of second outlets 6 c in the gas flow path 6 b , and flows out toward the first main surface of the substrate W from the plurality of second outlets 6 c .

[0085] Since the substrate W is heated by the heater 8, the second source gas supplied to the first main surface of the substrate W is thermally decomposed. The components generated by the thermal decomposition of the second source gas react with the active species derived from the first source gas, and the compound thereof is formed as a target film on the first main surface of the substrate W. When the first source gas is a gas containing nitrogen and the second source gas is an organic metal gas containing a group III element, the target film is a group III nitride semiconductor film.

[0086] The control unit 9 centrally controls the entire film forming apparatus 100 . For example, the control unit 9 controls the substrate holding unit 2 , the first gas supply unit 40 , the second gas supply unit 50 , the plasma source 5 , the suction unit 7 , and the heater 8 .

[0087] As described above, in the film forming apparatus 100, active species originating from the first raw material gas flows out from the plurality of first outlets 4c toward the first main surface of the substrate W, and the second raw material gas flows out from the plurality of second outlets 6c toward the first main surface of the substrate W. The plurality of first outlets 4c and the plurality of second outlets 6c do not overlap each other when viewed from above, and are dispersedly arranged in the overlapping region R0 overlapping with the first main surface of the substrate W, so that the active species and the second raw material gas are supplied more uniformly with respect to the first main surface of the substrate W. Therefore, the concentration distribution of the active species and the concentration distribution of the second raw material gas directly above the substrate W can be made more uniform. Therefore, the active species and the first raw material gas react with respect to the first main surface of the substrate W in a more uniform distribution. Therefore, the film forming apparatus 100 can form the target film on the first main surface of the substrate W with a more uniform film thickness. In the case where the first raw material gas contains a group V gas and the second raw material gas contains an organic metal gas containing a group III element, the film forming apparatus 100 can form a group III-V compound semiconductor film on the first main surface of the substrate W with a more uniform film thickness.

[0088] In addition, in the above-mentioned example, the flow path space 6b1 of the gas flow path 6b is located on the side opposite to the susceptor 21 with respect to the plasma chamber 4b. According to this structure, compared with the structure in which the gas flow path 6b is provided on the susceptor 21 side with respect to the plasma chamber 4b, the flow path space 6b1 is located farther from the substrate W and the heater 8. Therefore, the heat from the heater 8 is not easily transferred to the flow path space 6b1. Therefore, the possibility of thermal decomposition of the second raw material gas in the flow path space 6b1 can be reduced.

[0089] If the second raw material gas is thermally decomposed in the flow path space 6b1, various components generated by the thermal decomposition will precipitate on the inner peripheral surface forming the gas flow path 6b, causing the flow path area of ​​the gas flow path 6b to change. As a result, the uniformity of the flow of the second raw material gas may be reduced. In contrast, in the above example, since the thermal decomposition of the second raw material gas in the flow path space 6b1 can be suppressed, it is difficult to cause uneven flow of the second raw material gas. Therefore, the second raw material gas flows out more evenly from the plurality of second outlets 6c.

[0090] In other words, the plasma source 5 and the plasma chamber 4b are disposed at a position closer to the substrate W than the flow path space 6b1. Therefore, more active species can be supplied to the first main surface of the substrate W. That is, more active species can reach the first main surface of the substrate W before being deactivated. Thus, the film forming apparatus 100 can form a target film on the first main surface of the substrate W more efficiently.

[0091] In addition, the plasma source 5 is located between the flow path space 6b1 of the gas flow path 6b and the plasma chamber 4b. Thus, the plasma source 5 can be close to the plasma chamber 4b, and it is easy to generate an electric field for plasma in the plasma chamber 4b. That is, the plasma source 5 can generate an electric field for plasma in the plasma chamber 4b with high efficiency.

[0092] Next, a specific example of each structure will be described in detail.

[0093] <Substrate holding section>

[0094] The substrate holding portion 2 holds the substrate W in a horizontal position. Figure 1 In the example of , the substrate holding part 2 includes a susceptor 21 and a susceptor holding part 22. The susceptor 21 is a mounting table for mounting the substrate W, and has, for example, a flat plate shape. The susceptor 21 is set in a horizontal posture, and the substrate W is mounted in a horizontal posture on the upper surface of the susceptor 21. The first main surface (here, the upper surface) of the substrate W mounted on the susceptor 21 is exposed in the chamber 1.

[0095] The susceptor holding portion 22 is disposed in the chamber 1 and holds the susceptor 21. Figure 1 In the example of , the base holding portion 22 includes a base 221 and a holding protrusion 222. The base 221 is arranged below the base 21 in the vertical direction and faces the base 21 with a gap in the vertical direction. The base 221 has, for example, a horizontal upper surface, on which the holding protrusion 222 is vertically arranged. For example, a plurality of holding protrusions 222 are arranged along the peripheral portion of the lower surface of the base 21. The front end of the holding protrusion 222 abuts against the base 21 to support or hold the base 21.

[0096] like Figure 1 As shown, the substrate holding part 2 may further include a rotating mechanism 23. The rotating mechanism 23 rotates the base holding part 22 around the rotation axis Q1. The rotation axis Q1 is an axis that passes through the center of the substrate W and is along the vertical direction. The rotating mechanism 23 has, for example, a shaft and a motor. The upper end of the shaft is connected to the lower surface of the base 221. The shaft extends along the rotation axis Q1 and is axially supported in the chamber 1 so as to be rotatable around the rotation axis Q1. The motor rotates the shaft around the rotation axis Q1. As a result, the base holding part 22, the base 21 and the substrate W rotate integrally around the rotation axis Q1. In addition, the substrate holding part 2 may not include the rotating mechanism 23.

[0097] <Heater>

[0098] The heater 8 heats the substrate W held by the substrate holding portion 2 in the chamber 1. Figure 1In the example of , the heater 8 heats the substrate W from the second main surface (here, the lower surface). Specifically, the heater 8 is disposed vertically below the susceptor 21 and faces the susceptor 21 in the vertical direction. Figure 1 In the example, the heater 8 is provided between the base 21 and the seat 221 and radially inward of the holding protrusion 222. The heater 8 may be, for example, a resistive heater including a heating wire, or an optical heater including a light source for irradiating heating light.

[0099] Here, the heater 8 is provided so as not to rotate about the rotation axis Q1. That is, the heater 8 is non-rotatable. For example, the shaft of the rotating mechanism 23 is a hollow shaft, and the heater 8 is fixed to the chamber 1 via a fixing member 81 that passes through the hollow portion.

[0100] <Attraction Department>

[0101] The suction unit 7 sucks the gas in the chamber 1. Figure 1 In the example of FIG. 1 , the suction unit 7 includes a suction pipe 71 and a suction mechanism 72. The upstream end of the suction pipe 71 is connected to the exhaust port 1a of the chamber 1. Figure 1 In the example of , the exhaust port 1a is formed vertically below the substrate W held by the substrate holding portion 2, for example, formed on the side wall of the chamber 1. The suction mechanism 72 is, for example, a pump (more specifically, a vacuum pump), and is connected to the suction pipe 71. The suction mechanism 72 is controlled by the control unit 9 to suck the gas in the chamber 1 through the suction pipe 71.

[0102] <First gas supply unit>

[0103] The first gas supply unit 40 supplies the first raw material gas to the fluid head 3. Figure 1 In the example of , the first gas supply unit 40 includes a first gas supply pipe 401, a group V gas supply pipe 411, a hydrogen gas supply pipe 421, a valve 412, a valve 422, a flow rate adjustment unit 413, and a flow rate adjustment unit 423. The downstream end of the first gas supply pipe 401 is connected to the first inlet 4a of the fluid head 3. The upstream end of the first gas supply pipe 401 is commonly connected to the downstream end of the group V gas supply pipe 411 and the downstream end of the hydrogen gas supply pipe 421. The upstream end of the group V gas supply pipe 411 is connected to the group V gas supply source 414, and the upstream end of the hydrogen gas supply pipe 421 is connected to the hydrogen gas supply source 424. The group V gas supply source 414 includes a storage unit (not shown) for storing the group V gas, and the hydrogen gas supply source 424 includes a storage unit (not shown) for storing the hydrogen gas.

[0104] The valve 412 and the flow adjustment unit 413 are inserted into the group V gas supply pipe 411. The valve 412 switches the opening and closing of the flow path of the group V gas supply pipe 411. The flow adjustment unit 413 adjusts the flow rate of the group V gas flowing in the group V gas supply pipe 411. The flow adjustment unit 413 is, for example, a mass flow controller. The valve 422 and the flow adjustment unit 423 are inserted into the hydrogen supply pipe 421. The valve 422 switches the opening and closing of the flow path of the hydrogen supply pipe 421. The flow adjustment unit 423 adjusts the flow rate of the hydrogen gas flowing in the hydrogen supply pipe 421. The flow adjustment unit 423 is, for example, a mass flow controller.

[0105] <Second gas supply unit>

[0106] The second gas supply unit 50 supplies the second raw material gas to the fluid head 3. The second gas supply unit 50 includes a second gas supply pipe 501, a valve 502, and a flow adjustment unit 503. The downstream end of the second gas supply pipe 501 is connected to the second inlet 6a. The upstream end of the second gas supply pipe 501 is connected to the second gas supply source 504. The second gas supply source 504 includes a storage unit (not shown) for storing the second raw material gas. The second gas supply source 504 can supply not only the second raw material gas but also a carrier gas for transporting the second raw material gas to the upstream end of the second gas supply pipe 501. The carrier gas is an inert gas. As the inert gas, for example, at least any one of a rare gas such as argon and nitrogen can be used. In this case, the second raw material gas and the carrier gas flow out from the multiple second outlets 6c of the fluid head 3.

[0107] <Fluid head>

[0108] exist Figure 1 In the example shown in FIG. 4 , the fluid head 3 includes a first flow path member 4 , a plasma source 5 , and a second flow path member 6 . Figure 4 FIG. 1 is an exploded cross-sectional view showing an example of the structure of the fluid head 3. Figure 4 , the second flow path member 6, the plasma source 5, and the first flow path member 4 are shown separated from each other. The first flow path member 4 forms a plasma chamber 4b therein, and the second flow path member 6 forms a gas flow path 6b therein. Hereinafter, the plasma source 5 will be described after the second flow path member 6, and thereafter, the first flow path member 4 will be described.

[0109] <Second flow path member>

[0110] exist Figure 4 In the example of FIG. 1 , the second flow path member 6 includes a hollow plate portion 61 and a plurality of vertical pipes 65. The hollow plate portion 61 forms a flow path space 6b1 of a gas flow path 6b, and the plurality of vertical pipes 65 respectively form a plurality of through flow paths 6b2.

[0111] The hollow plate portion 61 has a flat shape whose dimension in the vertical direction is smaller than that in the horizontal direction, and includes an upper plate portion 62, a side wall 63, and a lower plate portion 64. The upper plate portion 62 has a flat plate shape, and is arranged in a posture along the vertical direction with its thickness direction. When viewed from above, the upper plate portion 62, for example, has a circular shape that is concentric with the substrate W. The diameter of the upper plate portion 62 can be greater than the diameter of the substrate W. The lower plate portion 64 has a flat plate shape, and is arranged in a posture along the vertical direction with its thickness direction. The lower plate portion 64 is located vertically below the upper plate portion 62, and when viewed from above, for example, has a circular shape that is concentric with the substrate W. The diameter of the lower plate portion 64 can be greater than the diameter of the substrate W. The side wall 63 connects the periphery of the upper plate portion 62 with the periphery of the lower plate portion 64 in the vertical direction. A second inlet 6a is formed at a portion of the side wall 63.

[0112] A plurality of through holes are formed in the lower plate portion 64. The upper ends of the plurality of vertical pipes 65 are connected to the lower plate portion 64 in such a manner that their respective upper ports are respectively consistent with the through holes of the lower plate portion 64. Each vertical pipe 65 has a cylindrical shape and extends downward from the lower plate portion 64 along the vertical direction. Each vertical pipe 65 has, for example, a cylindrical shape. Each vertical pipe 65 penetrates the plasma source 5 and the first flow path member 4 along the vertical direction as described later.

[0113] exist Figure 4 In the example, a front end portion 66 is provided at the lower end of each vertical pipe 65. The front end portion 66 has a plate-like shape in which a second flow outlet 6c is formed. The front end portion 66 has, for example, a disc-like shape, and its outer peripheral edge is connected to the peripheral edge of the lower end of the vertical pipe 65. The inner peripheral surface of the front end portion 66 forms the second flow outlet 6c. That is, the second flow outlet 6c is an opening that passes through the front end portion 66 in the vertical direction. In such a structure, the diameter of the second flow outlet 6c is smaller than the inner diameter of the vertical pipe 65. That is, the opening area of ​​the second flow outlet 6c is smaller than the flow path area of ​​the through flow path 6b2. Here, the opening area is the area of ​​the second flow outlet 6c on the horizontal plane, and the flow path area is the area of ​​the through flow path 6b2 on the horizontal plane.

[0114] <Plasma source>

[0115] The plasma source 5 is provided on the susceptor 21 side of the hollow plate portion 61 of the second flow path member 6. More specifically, the plasma source 5 is provided between the hollow plate portion 61 of the second flow path member 6 and the first flow path member 4. That is, the plasma source 5 is provided between the flow path space 6b1 of the gas flow path 6b and the plasma chamber 4b.

[0116] Reference Figure 4The plasma source 5 has a plurality of through holes 5d at positions corresponding to the plurality of vertical tubes 65 of the second flow path member 6 in the vertical direction. The plurality of through holes 5d penetrate the plasma source 5 in the vertical direction. The plurality of vertical tubes 65 penetrate the plurality of through holes 5d in the vertical direction. Each through hole 5d has, for example, a circular shape when viewed from above.

[0117] exist Figure 4 In the example, the plasma source 5 is a flat plasma source whose vertical dimension is smaller than the horizontal dimension. As a specific example, the plasma source 5 is a surface wave plasma source that generates surface wave plasma, and includes a waveguide member 51, a dielectric member 56, and a microwave generator 57.

[0118] Figure 5 and Figure 6 It is a cross-sectional view schematically showing an example of the structure of the plasma source 5 . Figure 5 Show Figure 4 The VV profile, Figure 6 Show Figure 4 Section VI-VI of the diagram.

[0119] The microwave generator 57 has an oscillator for oscillating microwaves. The oscillator may be, for example, a magnetron type oscillator or a solid-state type oscillator. The microwave generator 57 is disposed outside the substrate W in a plan view (see also Figure 1 ).

[0120] like Figure 4 and Figure 5 As shown in FIG. 5 , the waveguide member 51 is a hollow member that guides the microwaves generated by the microwave generator 57 to the dielectric member 56. The waveguide member 51 is formed of a conductive member such as metal. Figure 4 and Figure 5 In the example, the waveguide member 51 includes an upper plate portion 52, a side wall 53, a lower plate portion 54, and a plurality of hollow columnar portions 55. The upper plate portion 52 has a flat plate shape and is arranged in a posture in which its thickness direction is along the vertical direction. The upper plate portion 52 has, for example, a circular shape that is concentric with the substrate W when viewed from above. The diameter of the upper plate portion 52 may be greater than the diameter of the substrate W. The lower plate portion 54 has a flat plate shape and is arranged in a posture in which its thickness direction is along the vertical direction. The lower plate portion 54 is located vertically below the upper plate portion 52 and, for example, has a circular shape that is concentric with the substrate W when viewed from above. The diameter of the lower plate portion 54 may be greater than the diameter of the substrate W. The side wall 53 connects the periphery of the upper plate portion 52 and the periphery of the lower plate portion 54 in the vertical direction. A connection port 53a connected to the output end of the microwave generator 57 is formed in a portion of the side wall 53.

[0121] A plurality of hollow columns 55 are arranged between the upper plate 52 and the lower plate 54. The hollow column 55 has a cylindrical shape, and as a specific example, has a cylindrical shape. A plurality of through holes of a plurality of vertical pipes 65 that respectively penetrate the second flow path member 6 in the vertical direction are formed on the upper plate 52 and the lower plate 54. The upper ends of the plurality of hollow columns 55 are connected to the upper plate 52 in a manner that the upper ports of the plurality of hollow columns 55 are respectively consistent with the plurality of through holes of the upper plate 52, and the lower ends of the plurality of hollow columns 55 are connected to the lower plate 54 in a manner that the lower ports of the plurality of hollow columns 55 are respectively consistent with the plurality of through holes of the lower plate 54. That is, the through holes of the upper plate 52, the hollow parts of the hollow columns 55, and the through holes of the lower plate 54 are connected in the vertical direction, constituting the upper part of the through hole 5d that penetrates the plasma source 5.

[0122] In addition, a plurality of openings (also referred to as slots) 54a for guiding microwaves to the dielectric member 56 are formed in the lower plate portion 54 of the waveguide member 51. Microwaves from the microwave generator 57 pass through the inside of the waveguide member 51 and are transmitted to the dielectric member 56 from each opening 54a. Figure 5 In the example of FIG. 5 , the opening 54 a has a strip shape extending in one direction when viewed from above. The plurality of openings 54 a are arranged at intervals in the short side direction thereof. Figure 5 In the example of , the longitudinal direction of the opening 54 a is along the column direction of the matrix in which the plurality of hollow columnar portions 55 are arranged, and each opening 54 a is formed between two adjacent columns.

[0123] The dielectric member 56 is disposed vertically below the waveguide member 51. The dielectric member 56 is formed of a dielectric material (e.g., quartz glass). The dielectric member 56 has a flat plate shape, and has, for example, a circular shape concentric with the substrate W in a plan view (see also FIG. Figure 6 ). The diameter of the dielectric member 56 may be, for example, greater than the diameter of the substrate W. The upper surface of the dielectric member 56 is in contact with the lower surface of the waveguide member 51 (i.e., the lower surface of the lower plate portion 54) over its entire surface. The dielectric member 56 is provided with a plurality of through holes at positions facing the plurality of hollow columnar portions 55. Each through hole penetrates the dielectric member 56 in the vertical direction. That is, each through hole of the dielectric member 56 constitutes the lower portion of the corresponding through hole 5d.

[0124] The microwave from the opening 54a of the waveguide member 51 is transmitted inside the dielectric member 56 and acts on the lower surface side of the dielectric member 56. As a result, an electric field for plasma is generated along the lower surface of the dielectric member 56. As described later, the lower surface of the dielectric member 56 corresponds to the top surface of the plasma chamber 4b, so the electric field for plasma is generated in the plasma chamber 4b. Therefore, the electric field for plasma acts on the first raw material gas in the plasma chamber 4b, and the first raw material gas is plasmatized in the plasma chamber 4b. Since the lower surface of the dielectric member 56 extends in the horizontal direction, the first raw material gas can be plasmatized in a wide range when viewed from above.

[0125] In addition, in the above example, the plasma source 5 generates surface wave plasma using microwaves, but it is not necessarily limited to this. The plasma source 5 can also generate plasma in a so-called capacitive coupling method or inductive coupling method. Another specific example of the plasma source 5 will be described later.

[0126] <First flow path member>

[0127] The first flow path member 4 is disposed vertically below the plasma source 5. The first flow path member 4 and the plasma source 5 together form a plasma chamber 4b. Figure 4 In the example of , the first flow path member 4 includes a side wall 43, a lower plate portion 44 and a plurality of hollow columnar portions 45. The lower plate portion 44 has a flat plate shape and is arranged with its thickness direction along the vertical direction. The lower plate portion 44 has, for example, a circular shape that is concentric with the substrate W when viewed from above. The diameter of the lower plate portion 44 may be, for example, greater than the diameter of the substrate W. The side wall 43 connects the periphery of the lower plate portion 44 to the periphery of the dielectric member 56 of the plasma source 5.

[0128] The lower plate portion 44 is provided with a plurality of through holes of a plurality of vertical pipes 65 that respectively penetrate the second flow path member 6 in the vertical direction, and the lower ends of the plurality of hollow column portions 45 are connected to the lower plate portion 44 in such a manner that the lower ports of the plurality of hollow column portions 45 are respectively consistent with the plurality of through holes of the lower plate portion 44. In addition, the upper ends of the plurality of hollow column portions 45 can be connected to the lower surface of the dielectric member 56 in such a manner that the upper ports of the plurality of hollow column portions 45 are respectively consistent with the plurality of through holes 5d of the plasma source 5. The hollow portions of the plurality of hollow column portions 45 and the through holes of the lower plate portion 44 are equivalent to the through holes 4d that penetrate the first flow path member 4 in the vertical direction. Each of the vertical pipes 65 of the second flow path member 6 penetrates each of the through holes 4d of the first flow path member 4. Each through hole 4d has a circular shape, for example, when viewed from above.

[0129] A plurality of first outlets 4c are also formed on the lower plate portion 44. Figure 2 In the example of , the first outlets 4c and the second outlets 6c are alternately arranged at equal intervals in the oblique direction. Figure 2 In the example of , when viewed from above, one first outlet 4c is located at the midpoint of the diagonal line of the quadrilateral having four second outlets 6c as vertices. In addition, one second outlet 6c is located at the midpoint of the diagonal line of the quadrilateral having four first outlets 4c as vertices.

[0130] <Control Department>

[0131] Figure 7 This is a block diagram schematically showing an example of the structure of the control unit 9. The control unit 9 is an electronic circuit machine, and may also have, for example, a data processing device 91 and a storage unit 92. The data processing device 91 is, for example, a calculation processing device such as a CPU (Central Processor Unit). The storage unit 92 may have a non-temporary storage unit 921 (for example, a ROM (Read Only Memory) or a hard disk) and a temporary storage unit 922 (for example, a RAM (Random Access Memory)). In the non-temporary storage unit 921, for example, a program that specifies the processing performed by the control unit 9 may also be stored. By executing the program by the data processing device 91, the control unit 9 can perform the processing specified by the program. Of course, part or all of the processing performed by the control unit 9 may also be performed by a hardware circuit such as a logic circuit.

[0132] <Operation of film forming equipment>

[0133] Next, an example of the operation of the film forming apparatus 100 is summarized. First, an external conveying device (not shown) carries the substrate W into the chamber 1 and delivers it to the substrate holding portion 2. Thus, the substrate W is placed on the base 21 of the substrate holding portion 2 in a horizontal position. Next, the suction portion 7 sucks the gas in the chamber 1 to reduce the pressure in the chamber 1 (decompression process). Specifically, the control portion 9 causes the suction mechanism 72 to perform a suction operation. Thus, the gas in the chamber 1 is sucked into the suction mechanism 72 through the suction pipe 71, and the pressure in the chamber 1 is reduced. The suction portion 7 adjusts the pressure in the chamber 1 in such a way that the pressure in the chamber 1 becomes a prescribed process pressure suitable for the film forming process. The prescribed process pressure is, for example, greater than 100 Pa and less than 500 Pa. The suction portion 7 adjusts the pressure in the chamber 1 until the film forming process is completed.

[0134] Next, the heater 8 heats the substrate W (heating process). Specifically, the control unit 9 causes the heater 8 to perform a heating operation. The heater 8 adjusts the temperature of the substrate W so that the temperature of the substrate W becomes a predetermined temperature suitable for the film forming process. The predetermined temperature is, for example, 600° C. or more and 1000° C. or less. The heater 8 adjusts the temperature of the substrate W until the film forming process is completed.

[0135] Next, the substrate holding unit 2 rotates the substrate W around the rotation axis Q1 (rotation process). Specifically, the control unit 9 instructs the rotation mechanism 23 to rotate the susceptor holding unit 22. As a result, the susceptor holding unit 22, the susceptor 21, and the substrate W rotate integrally around the rotation axis Q1. The substrate holding unit 2 rotates the substrate W until the film forming process is completed.

[0136] Next, the first gas supply unit 40 supplies the first raw material gas to the fluid head 3, the second gas supply unit 50 supplies the second raw material gas to the fluid head 3, and the plasma source 5 excites the first raw material gas into plasma (film forming process). Specifically, the control unit 9 opens the valves 412, 422, and 502 to enable the microwave generator 57 to generate microwaves. As a result, active species derived from the first raw material gas flow out from the multiple first outlets 4c of the fluid head 3 toward the first main surface of the substrate W, and the second raw material gas flows out from the multiple second outlets 6c of the fluid head 3 toward the first main surface of the substrate W.

[0137] The second raw material gas is thermally decomposed on the first main surface of the substrate W, and the components generated by the thermal decomposition react with the active species, thereby forming a target film on the first main surface of the substrate W. As a more specific example, the group III element generated by the thermal decomposition of the organic metal gas containing the group III element reacts with nitrogen radicals, and the group III nitride semiconductor grows on the first main surface of the substrate W.

[0138] When the target film is formed with a predetermined film thickness, the control unit 9 ends the film forming process. Specifically, the control unit 9 closes valves 412, 422, and 502, and stops the microwave output of the microwave generator 57. In addition, the control unit 9 stops the operation of the rotating mechanism 23, the heater 8, and the suction unit 7.

[0139] Next, the transport device carries out the substrate W from the chamber 1 (carry-out step). Specifically, the transport device carries out the substrate W placed on the susceptor 21 from the chamber 1 .

[0140] <Function>

[0141] As described above, in the film forming process, active species from the first raw material gas flow out toward the first main surface of the substrate W from the plurality of first outflow ports 4c two-dimensionally dispersedly arranged in the overlapping region R0 overlapping the substrate W when viewed from above. Similarly, the second raw material also flows out toward the first main surface of the substrate W from the plurality of second outflow ports 6c two-dimensionally dispersedly arranged in the overlapping region R0. Therefore, the active species and the second raw material gas are more uniformly supplied to the first main surface of the substrate W, and as a result, the target film is formed more uniformly on the first main surface of the substrate W.

[0142] in addition, Figures 1 to 6The illustrated plasma source 5 is a flat plasma source whose horizontal dimension is larger than its vertical dimension, and thus, when viewed from above, plasma can be generated more uniformly over a wider range. The plasma source 5 can generate plasma over a wider range than the overlap region R0 when viewed from above. Thus, active species generated by the plasma can be supplied more uniformly to the first main surface of the substrate W. Furthermore, the film forming apparatus 100 can form the target film on the first main surface of the substrate W more uniformly.

[0143] In addition, Figures 1 to 6 In the illustrated fluid head 3, the second flow outlet 6c is formed at the front end 66 of the vertical pipe 65. Therefore, even if the inner diameter of the vertical pipe 65 (i.e., the flow path area of ​​the through flow path 6b2) is enlarged, the diameter of the second flow outlet 6c (i.e., the opening area) can be reduced. If the inner diameter of the vertical pipe 65 is large, the second raw material gas is easy to flow in the vertical pipe 65. On the other hand, since the diameter of the second flow outlet 6c is small, the distance between the periphery of the second flow outlet 6c and the periphery of the first flow outlet 4c can be extended. Therefore, the possibility of the active species flowing out of the first flow outlet 4c reaching the second flow outlet 6c can be reduced.

[0144] If more active species reach the second outlet 6c, the active species react with the second raw material gas, and there is a possibility that the compound is formed on the inner peripheral surface of the front end portion 66 near the second outlet 6c. If the opening area of ​​the second outlet 6c is changed by such a compound film, for example, the flow rate and flow rate of the second raw material gas flowing out of the plurality of second outlets 6c may deviate. This may cause unevenness of the target film on the substrate W. In the above example, since the possibility of the active species flowing out of the first outlet 4c reaching the second outlet 6c can be reduced, the possibility of such an undesirable situation can be reduced.

[0145] In addition, Figure 1 In the example of , the vertical pipe 65 passes through the plasma source 5 and the first flow path member 4, and its front end portion 66 is located vertically below the first flow path member 4. That is, each second flow outlet 6c formed at the front end portion 66 is located vertically below each first flow outlet 4c formed at the lower portion of the first flow path member 4. Furthermore, in other words, each second flow outlet 6c is located closer to the base 21 side than each first flow outlet 4c. Thus, the distance between the second flow outlet 6c and the first flow outlet 4c can also be extended. Therefore, the possibility of the active species flowing out of the first flow outlet 4c reaching the second flow outlet 6c can be further reduced.

[0146] <Partitioning member>

[0147] Inside the fluid head 3, the plasma chamber 4b and the gas flow path 6b are separated from each other. In the above example, the plasma chamber 4b and the gas flow path 6b are separated from each other by the lower plate 64 of the second flow path member 6, the plasma source 5, the vertical pipe 65 of the second flow path member 6, and the hollow column 45 of the first flow path member 4. That is, these components function as partition members. However, it is not necessarily limited to this. For example, since the plasma source 5 can function as a partition member that separates the plasma chamber 4b from the flow path space 6b1 of the gas flow path 6b, it is not necessary to set the lower plate 64. In this case, the lower end periphery of the side wall 63 of the second flow path member 6 can be connected to the plasma source 5. In addition, the vertical pipe 65 and the hollow column 45 can function as a partition member that separates the plasma chamber 4b from the through flow path 6b2 of the gas flow path 6b. Therefore, one of the vertical pipe 65 and the hollow column 45 can also be omitted. Specifically, for example, the portion other than the protruding portion protruding from the first flow path member 4 in the vertical pipe 65 may be omitted. In this case, the protruding portion may be connected to the first flow path member 4. Alternatively, the hollow columnar portion 45 may be omitted. In this case, the inner peripheral surface of each through hole of the lower plate portion 44 of the first flow path member 4 may be connected to the outer peripheral surface of the corresponding vertical pipe 65.

[0148] <Shielding parts>

[0149] The fluid head 3 may include at least a conductive shielding member disposed between the plasma chamber 4b and the through-flow path 6b2. For example, at least a portion of each vertical tube 65 of the second flow path member 6 that is adjacent to the plasma chamber 4b in the horizontal direction may also include a conductive member such as metal. That is, the portion may be composed of a conductive material such as metal. The conductive member of each vertical tube 65 has a cylindrical shape that surrounds the through-flow path 6b2. The conductive member can function as a conductive shielding member that electrically shields the plasma chamber 4b and the through-flow path 6b2 from each other.

[0150] The conductive member of each vertical pipe 65 may be grounded. This can improve the shielding performance. For example, the entire second flow path member 6 may be made of a conductive member such as metal, and the second flow path member 6 may be grounded via a predetermined wiring.

[0151] According to such a structure, although the electric field for plasma generated by the plasma source 5 is generated in the plasma chamber 4b, it is difficult to generate in the vertical tube 65 (i.e., the through-flow path 6b2) of the second flow path member 6 by the conductive shield (the above-mentioned conductive member). Since the plasma source 5 generates an electric field for plasma along the vertical downward direction, the electric field for plasma is almost not generated in the space adjacent to the plasma source 5 in the horizontal direction and the space in the vertical direction of the plasma source 5. However, in the case where the plasma source 5 generates an electric field in these spaces, the entire second flow path member 6 can be composed of a conductive member. In this case, the entire second flow path member 6 functions as a conductive shield. Therefore, it is difficult for the electric field to be generated in the entire gas flow path 6b, and the electric field is difficult to act on the second raw material gas. Therefore, it is possible to suppress the unnecessary electric field from being applied to the second raw material gas, and it is possible to suppress the plasmaization of the second raw material gas. In addition, in the case where the carrier gas is supplied to the fluid head 3 together with the second raw material gas, it is also possible to suppress the plasmaization of the carrier gas.

[0152] <Other specific examples of fluid heads>

[0153] Figure 8 FIG. 2 is a diagram schematically showing another example of the fluid head 3 according to the first embodiment. Figure 8 In the example of FIG. 4 , the fluid head 3 also has a first inlet 4a, a plasma chamber 4b, a plurality of first outlets 4c, a second inlet 6a, a gas flow path 6b, and a plurality of second outlets 6c. Figure 8 In the example shown in FIG. 5 , the fluid head 3 includes a plasma source 5A and a flow path member 6A.

[0154] The flow path member 6A has the same structure as the second flow path member 6 except for the presence or absence of a connection port 6d for supplying power to the plasma source 5A. The connection port 6d will be described later.

[0155] Fig. 9 Yes Figure 8 FIG. 3 is a diagram schematically showing the various structures of the fluid head 3 in an exploded manner. Fig.10 It is schematically shown Fig. 9 The XX section of the diagram. Fig. 9 In the example of FIG. 5 , the plasma source 5A is a hollow cathode discharge type plasma source, including a first electrode 510 and a second electrode 521. The first electrode 510 and the second electrode 521 are formed of conductive members such as metal. Fig. 9 and Fig.10 As shown, the first electrode 510 has a plate shape. Fig.10 In the example of FIG. 5 , the first electrode 510 has a circular shape that is concentric with the substrate W in a plan view. The diameter of the first electrode 510 may be greater than the diameter of the substrate W.

[0156] A plurality of through holes 512 through which the plurality of vertical tubes 65 of the flow path member 6A respectively penetrate are formed in the first electrode 510. Each through hole 512 penetrates the first electrode 510 in the vertical direction. Each through hole 512 has, for example, a circular shape in a plan view.

[0157] A plurality of recesses 511 are formed on the surface (here, the lower surface) on the side of the base 21 in the first electrode 510. The plurality of recesses 511 are formed at positions different from those of the through holes 512. Fig.10 In the example of FIG. 1 , the plurality of recesses 511 are two-dimensionally dispersedly arranged at positions different from the plurality of through holes 512 in the overlapping region R0 overlapping with the substrate W when viewed from above. The plurality of recesses 511 may also be dispersedly arranged in a region facing a large portion of the overlapping region R0. As a more specific example, the plurality of recesses 511 may be dispersedly arranged in a circular region having a diameter greater than one-half of the diameter of the substrate W and being concentric with the substrate W.

[0158] exist Fig. 9 and Fig.10 In the example of , each recess 511 is formed in a columnar shape extending in the vertical direction, and has, for example, a circular shape when viewed from above. Fig. 9 In the example of , the depth of each recess 511 is greater than the thickness between the bottom surface of each recess 511 and the upper surface of the first electrode 510. The portion around each recess 511 in the first electrode 510 constitutes a so-called hollow cathode. That is, the first electrode 510 forms a plurality of hollow cathodes that are dispersed in two dimensions when viewed from above. Fig. 9 In the example of FIG. 5 , the recessed portion 511 and the first outflow port 4 c face each other one-to-one in the vertical direction.

[0159] The second electrode 521 is located on the base 21 side relative to the first electrode 510. Here, the second electrode 521 is located vertically below the first electrode 510. The second electrode 521 has a plate-like shape, and when viewed from above, for example, has a circular shape that is concentric with the substrate W. The diameter of the second electrode 521 can be greater than the diameter of the substrate W. The second electrode 521 has, for example, the same shape as the lower plate portion 44 of the first flow path member 4. The second electrode 521 has conductivity and forms a so-called anode.

[0160] The second electrode 521 is provided with a plurality of through holes 523 through which the plurality of vertical tubes 65 of the flow path member 6A respectively penetrate. The through holes 523 penetrate the second electrode 521 in the vertical direction. Each through hole 523 has, for example, a circular shape when viewed from above. The through hole 512 of the first electrode 510 and the through hole 523 of the second electrode 521 correspond to the through hole 5d that penetrates the plasma source 5A.

[0161] exist Fig. 9In the example of , a side wall 522 is erected at the periphery of the second electrode 521. The side wall 522 extends from the entire periphery of the second electrode 521 toward the first electrode 510. The side wall 522 can be integrally formed with the second electrode 521 by the same material, or can be separately formed by a material different from the second electrode 521. Here, the side wall 522 is integrally formed with the second electrode 521 by the same material.

[0162] exist Fig. 9 In the example of , an insulating member 533 is provided between the periphery of the first electrode 510 and the side wall 522. The insulating member 533 ensures insulation between the first electrode 510 and the side wall 522. The insulating member 533 has a plate-like shape and has a ring-like shape when viewed from above. The insulating member 533 can prevent a short circuit between the first electrode 510 and the second electrode 521.

[0163] The space surrounded by the first electrode 510, the second electrode 521 and the side wall 522 corresponds to the plasma chamber 4b. That is, the first electrode 510 as a part of the plasma source 5A is provided between the flow path space 6b1 and the plasma chamber 4b. A first inlet 4a is formed in a part of the side wall 522, and a plurality of first outlets 4c are formed in the second electrode 521. Each first outlet 4c penetrates the second electrode 521 in the vertical direction.

[0164] A plasma voltage is applied between the first electrode 510 and the second electrode 521 by a plasma power supply 540. Figure 8 In the example of FIG. 5 , the first output terminal of the power supply 540 is electrically connected to the first electrode 510, and the second output terminal of the power supply 540 and the second electrode 521 are grounded. The power supply 540 outputs, for example, a high-frequency voltage. By applying the voltage between the first electrode 510 and the second electrode 521, an electric field for plasma is generated in the plasma chamber 4b between the first electrode 510 and the second electrode 521, and the first raw material gas in the plasma chamber 4b is plasmatized. Active species generated by plasmatization flow out from the plurality of first outlets 4c.

[0165] Next, the flow path member 6A is described. Here, as an example, the flow path member 6A is formed of a conductive member. Thus, the flow path member 6A can electrically shield the gas flow path 6b from the outside, and can suppress the electric field for plasma generation in the gas flow path 6b. In the case where the flow path member 6A has conductivity, such as Figure 8 and Fig. 9 As illustrated, an insulating member 530 for insulating the plasma source 5A from the flow path member 6A may be provided on the fluid head 3. Fig. 9As shown, the insulating member 530 includes a plate portion 531 and a plurality of cylindrical portions 532. The plate portion 531 has a plate-like shape and is disposed between the hollow plate portion 61 of the flow path member 6A and the first electrode 510 of the plasma source 5A. The plate portion 531 ensures insulation between the hollow plate portion 61 and the first electrode 510. The plate portion 531 has, for example, a circular shape that is concentric with the substrate W when viewed from above. The diameter of the plate portion 531 is greater than the diameter of the hollow plate portion 61 and the first electrode 510. A plurality of through holes are formed in the plate portion 531, and a plurality of vertical pipes 65 of the flow path member 6A are respectively passed through the plurality of through holes.

[0166] The plurality of barrels 532 have a cylindrical shape, and are connected to the plate portion 531 in a manner such that their upper ports coincide with the through holes of the plate portion 531. The plurality of barrels 532 extend from the plate portion 531 toward the base 21 side. The plurality of vertical pipes 65 of the flow path member 6A penetrate the plurality of barrels 532, respectively. The barrel 532 is disposed between the first electrode 510 and the vertical pipe 65, and between the second electrode 521 and the vertical pipe 65. Therefore, the barrel 532 can ensure insulation between the first electrode 510 and the vertical pipe 65, and can ensure insulation between the second electrode 521 and the vertical pipe 65. In other words, a short circuit between the first electrode 510 and the second electrode 521 through the vertical pipe 65 can be avoided.

[0167] exist Figure 8 In the example of FIG. 5 , a connection port 6d for a power source connected to the first electrode 510 is formed on the fluid head 3. The connection port 6d is formed at a position different from the plurality of vertical pipes 65 in a plan view, and penetrates the hollow plate portion 61 of the flow path member 6A and the plate portion 531 of the insulating member 530 in the vertical direction. Fig. 9 In the example of FIG. 6 , a hollow column 67 surrounding the connection port 6d is further provided on the hollow plate portion 61. The hollow column 67 has a cylindrical shape, and connects the upper plate portion 62 and the lower plate portion 64 in such a manner that its upper port coincides with the through hole formed in the upper plate portion 62 and its lower port coincides with the through hole formed in the lower plate portion 64. The through hole of the upper plate portion 62, the hollow column 67, and the through hole of the lower plate portion 64 correspond to the upper portion of the connection port 6d.

[0168] The first electrode 510 is electrically connected to one end of a wiring 541 at the connection port 6 d , and the other end of the wiring 541 is electrically connected to a first output terminal of the power source 540 .

[0169] Fig.11 It is schematically shown Figure 8 The XI-XI section of Fig.11 As shown, a plurality of connection ports 6d may be formed on the fluid head 3. The plurality of connection ports 6d are formed at different positions when viewed from above. For example, the plurality of connection ports 6d may be formed at equal intervals in the circumferential direction. Figure 8In the example of FIG. 1 , four connection ports 6 d are formed at positions corresponding to vertices of a virtual square.

[0170] The first electrode 510 is electrically connected to one end of the wiring 541 at each connection port 6d. Since the first electrode 510 is electrically connected to one end of the plurality of wirings 541 at the plurality of connection ports 6d, voltage is applied to the first electrode 510 at a plurality of locations. Thus, the voltage distribution (potential distribution) of the first electrode 510 can be made more uniform. Furthermore, the plasma source 5A can generate plasma more uniformly when viewed from above.

[0171] <Second embodiment>

[0172] The film forming apparatus 100 of the second embodiment has the same structure as that of the first embodiment except for the structure of the fluid head 3. Hereinafter, the fluid head 3 of the second embodiment is referred to as a fluid head 3A.

[0173] Fig.12 FIG. 2 is a cross-sectional view schematically showing an example of the structure of the fluid head 3A according to the second embodiment. Fig.12 In the example of FIG. 3 , the fluid head 3A further includes a first flow path member 4 , a plasma source 5 , a second flow path member 6 , and a cooling portion 30 .

[0174] The cooling unit 30 cools the plasma source 5. Fig.12 In the example of FIG. 5 , the cooling unit 30 is provided between the hollow plate portion 61 of the second flow path member 6 and the plasma source 5. The cooling unit 30 is provided with a plurality of through holes 30d through which the plurality of vertical pipes 65 (through flow paths 6b2) of the second flow path member 6 respectively penetrate.

[0175] Fig.13 FIG. 1 is a cross-sectional view schematically showing an example of the structure of the cooling unit 30. Fig.13 In the example of FIG. 1 , the cooling unit 30 is a refrigerant type cooling unit and includes a thermally conductive member 31 , a refrigerant pipe 32 , and a refrigerant cooling unit 33 .

[0176] The thermally conductive member 31 is made of a material having high thermal conductivity, such as metal. The thermally conductive member 31 has a plate-like shape, and is disposed with its thickness direction along the vertical direction. The thermally conductive member 31 has, for example, a circular shape that is concentric with the substrate W when viewed from above. The diameter of the thermally conductive member 31 may be, for example, greater than the diameter of the plasma source 5 (specifically, the waveguide member 51). The thermally conductive member 31 may be in close contact with the waveguide member 51 of the plasma source 5.

[0177] A plurality of through holes 30d and a coolant flow path 30a are formed in the thermal conductive member 31. The plurality of through holes 30d are formed at positions facing the plurality of vertical pipes 65, respectively, and vertically penetrate the thermal conductive member 31. The plurality of vertical pipes 65 of the second flow path member 6 penetrate the plurality of through holes 30d of the cooling unit 30, respectively.

[0178] exist Fig.13 In the example of FIG. 1 , the upstream end and the downstream end of the coolant flow path 30a are formed on the side surface of the thermal conductive member 31. The coolant flow path 30a extends in the thermal conductive member 31 so as not to interfere with the through hole 30d. Fig.13 The example is a zigzag stretch.

[0179] The upstream end of the refrigerant flow path 30a is connected to the downstream end of the refrigerant pipe 32, and the downstream end of the refrigerant flow path 30a is connected to the upstream end of the refrigerant pipe 32. A refrigerant such as water flows and circulates in the refrigerant pipe 32 and the refrigerant flow path 30a.

[0180] The refrigerant cooling unit 33 cools the refrigerant flowing in the refrigerant pipe 32. The refrigerant cooling unit 33 may be, for example, a heat pump unit. The low-temperature refrigerant cooled by the refrigerant cooling unit 33 exchanges heat with the thermal conductive member 31 in the refrigerant flow path 30a. As a result, the refrigerant receives heat from the thermal conductive member 31 and cools the thermal conductive member 31. The thermal conductive member 31 exchanges heat with the plasma source 5 and receives heat from the plasma source 5, thereby cooling the plasma source 5. On the other hand, since the refrigerant receives heat from the thermal conductive member 31, the temperature of the refrigerant rises. The refrigerant is cooled again in the refrigerant cooling unit 33.

[0181] As described above, in the fluid head 3A, the cooling unit 30 cools the plasma source 5. This can suppress a temperature rise in the plasma source 5. Therefore, thermal degradation of the plasma source 5 and its surrounding members (eg, the first flow path member 4) can be suppressed.

[0182] In addition, in the above-mentioned example, the cooling unit 30 is provided on the side opposite to the susceptor 21 with respect to the plasma source 5. Therefore, the cooling unit 30 does not hinder the generation and supply of active species by the plasma source 5 and the first flow path member 4 to the substrate W. In addition, the cooling unit 30 can face the plasma source 5 with a wider area, and can cool the plasma source 5 with a wider area. Therefore, the cooling unit 30 can cool the plasma source 5 more effectively.

[0183] In addition, since the cooling unit 30 is provided between the hollow plate portion 61 and the plasma source 5, the heat conduction from the plasma source 5 to the hollow plate portion 61 can also be effectively suppressed. Therefore, the possibility of thermal decomposition of the second raw material gas in the flow path space 6b1 in the hollow plate portion 61 can be further reduced. In addition, the cooling unit 30 can also cool the hollow plate portion 61. For example, when the heat conductive member 31 is in close contact with the lower plate portion 64 of the hollow plate portion 61, the cooling unit 30 can effectively cool the hollow plate portion 61.

[0184] In addition, the cooling unit 30 does not need to be disposed between the hollow plate portion 61 and the plasma source 5. For example, the cooling unit 30 may be disposed on the side opposite to the plasma source 5 relative to the hollow plate portion 61, and may be disposed vertically above the hollow plate portion 61. Alternatively, the first cooling unit 30 may be disposed vertically above the hollow plate portion 61, and the second cooling unit 30 may be disposed between the hollow plate portion 61 and the plasma source 5.

[0185] In addition, you can also Figure 8 The fluid head 3 is provided with a cooling portion 30 for cooling the plasma source 5A. For example, the cooling portion 30 may be provided between the hollow plate portion 61 of the flow path member 6A and the plasma source 5A.

[0186] <Third embodiment>

[0187] An example of the structure of the film forming apparatus 100 of the third embodiment is the same as that of the first embodiment or the second embodiment. However, in the third embodiment, the structure of the flow path of the fluid head 3 is different from that of the fluid head 3 of the first embodiment or the second embodiment.

[0188] Fig.14 1 is a cross-sectional view schematically showing an example of the structure of the second flow path member 6 of the fluid head 3 according to the third embodiment. Fig.14 In the example of , a plurality of second inlets 6a are formed on the side wall 63 of the second flow path member 6. The plurality of second inlets 6a are formed on the side wall 63 at approximately equal intervals in the circumferential direction. According to this structure, the second raw material gas flows into the gas flow path 6b (specifically, the flow path space 6b1) from the plurality of second inlets 6a. Therefore, the flow of the second raw material gas in the gas flow path 6b is more uniform, and the second raw material gas flows out more uniformly from the plurality of second outlets 6c.

[0189] In addition, the second flow outlet 6c on the outer side of the plurality of second flow outlets 6c is closer to any second inlet 6a than the second flow outlet 6c on the central side. Therefore, from the perspective of the length of the flow path of the second raw gas, the second raw gas easily reaches the second flow outlet 6c on the outer side, but is difficult to reach the second flow outlet 6c on the central side. That is, from the perspective of the length of the flow path, the second raw gas easily flows out from the second flow outlet 6c on the outer side, but is difficult to flow out from the second flow outlet 6c on the central side. Therefore, from the perspective of the length of the flow path, the second raw gas can flow out from the second flow outlet 6c on the outer side at a flow rate slightly larger than the second flow outlet 6c on the central side.

[0190] Therefore, in Fig.14 In the example of , the opening area of ​​the second outlet 6c on the central side is set to be larger than the opening area of ​​the second outlet 6c on the peripheral side. For example, the opening area of ​​all the second outlets 6c in the central region R1 in the overlapping region R0 is larger than the opening area of ​​all the second outlets 6c in the peripheral region R2 outside the central region R1 in the overlapping region R0. Therefore, from the perspective of the size of the opening area, it is difficult for the second raw material gas to flow out from the second outlet 6c on the peripheral side, and it is easy for the second raw material gas to flow out from the second outlet 6c on the central side.

[0191] Therefore, it is possible to reduce the variation in the flow rate of the second material gas flowing out from the second outlets 6 c on the central side and the outer peripheral side. In other words, the second material gas flows out from the plurality of second outlets 6 c more uniformly.

[0192] exist Fig.14 In the example, the flow area of ​​the through flow path 6b2 on the central side of the plurality of through flow paths 6b2 is larger than the flow area of ​​the through flow path 6b2 on the peripheral side. As a more specific example, the flow area of ​​all through flow paths 6b2 in the central region R1 is larger than the flow area of ​​all through flow paths 6b2 in the peripheral region R2. In other words, the flow area of ​​each vertical pipe 65 in the central region R1 is larger than the flow area of ​​each vertical pipe 65 in the peripheral region R2. Thus, the deviation of the flow rate of the second raw material gas between the plurality of through flow paths 6b2 can also be reduced. Furthermore, the second raw material gas flows out more evenly from the plurality of second outlets 6c.

[0193] In addition, in order to reduce the deviation of the second raw material gas between the multiple second flow outlets 6c, it is not necessary to set the opening area of ​​the second flow outlet 6c on the central side to be larger than the opening area of ​​the second flow outlet 6c on the peripheral side. Here, the opening ratio is introduced for explanation. The opening ratio is the ratio of the sum of the opening areas of the second flow outlets 6c in a specified area to the area of ​​the specified area. The larger the opening ratio, the easier it is for the second raw material gas to flow in the second flow outlet 6c. Therefore, it is sufficient to make the opening ratio of the second flow outlet 6c on the central side larger than the opening ratio of the second flow outlet 6c on the peripheral side.

[0194] Fig.15 FIG. 2 is a cross-sectional view schematically showing another example of the structure of the second flow path member 6 of the fluid head 3 according to the third embodiment. Fig.15 In the example of , the pitch of the second outlets 6c located in the central region R1 is narrower than the pitch of the second outlets 6c located in the peripheral region R2. Therefore, the opening ratio of the second outlet 6c in the central region R1 is larger than the opening ratio of the second outlet 6c in the peripheral region R2. Therefore, the deviation of the flow rate of the second raw material gas flowing out from the second outlets 6c on the central side and the peripheral side can be reduced. In other words, the second raw material gas flows out more evenly from the plurality of second outlets 6c.

[0195] Fig.16 FIG. 1 is a cross-sectional view schematically showing an example of the structure of the fluid head 3 according to the third embodiment. Fig.16 In the example of , the second inlet 6a is formed not only on the side wall 63 of the second flow path member 6, but also on the upper plate portion 62. Specifically, the second inlet 6a is formed in the central portion of the upper plate portion 62. In other words, the second inlet 6a is formed above the central portion of the flow path space 6b1. The second inlet 6a of the upper plate portion 62 is formed, for example, at a position aligned with the center of the substrate W in the vertical direction.

[0196] According to this structure, the second raw material gas flows into the gas flow path 6b (more specifically, the flow path space 6b1) not only from the plurality of second inlet ports 6a at the side portion, but also from the second inlet port 6a at the upper portion of the central portion. Therefore, the flow of the second raw material gas in the flow path space 6b1 of the gas flow path 6b can be further uniformized. Therefore, the second raw material gas flows out from the plurality of second outlet ports 6c more uniformly.

[0197] The opening ratio of the first outflow port 4c can also be set in the same manner as that of the second outflow port 6c. Fig.17 1 is a cross-sectional view schematically showing an example of the structure of the first flow path member 4 of the fluid head 3 according to the third embodiment. Fig.17In the example of , a plurality of first inlet ports 4a are formed on the side wall 43 of the first flow path member 4. The plurality of first inlet ports 4a are formed on the side wall 43 at substantially equal intervals in the circumferential direction. According to this structure, the first raw material gas flows into the plasma chamber 4b from the plurality of first inlet ports 4a. Therefore, the flow of the first raw material gas in the plasma chamber 4b is more uniform, and the active species derived from the first raw material gas flows out more uniformly from the plurality of first outlet ports 4c.

[0198] exist Fig.17 In the example, the opening ratio of the first flow outlet 4c on the central side is set to be larger than the opening ratio of the first flow outlet 4c on the peripheral side. For example, when viewed from above, the opening area of ​​all the first flow outlets 4c in the central region R1 is larger than the opening area of ​​all the first flow outlets 4c in the peripheral region R2. Therefore, from the perspective of the size of the opening area, it is difficult for the active species originating from the first raw gas to flow out from the first flow outlet 4c on the peripheral side, and it is easy for the active species to flow out from the first flow outlet 4c on the central side. Therefore, it is possible to reduce the deviation in the flow rate of the active species flowing out of the first flow outlets 4c on the central side and the peripheral side. In other words, the active species flow out more evenly from multiple first flow outlets 4c.

[0199] In addition, the pitch of the first outflow ports 4 c on the center side may be set smaller than the pitch of the first outflow ports 4 c on the outer peripheral side.

[0200] In the above example, the fluid head 3 including the first flow path member 4 , the plasma source 5 , and the second flow path member 6 is described, but the same is true for the fluid head 3 including the plasma source 5A and the flow path member 6A.

[0201] <Fourth embodiment>

[0202] An example of the structure of the film forming apparatus 100 of the fourth embodiment is the same as the structure of any one of the first to third embodiments. However, in the fourth embodiment, the structure of the second gas supply unit 50 is different from the second gas supply unit 50 of the first to third embodiments. The second gas supply unit 50 can switch between a state in which both the second raw material gas and the carrier gas are supplied to the fluid head 3 and a state in which the carrier gas is supplied to the fluid head 3 without supplying the second raw material gas. The carrier gas mentioned here is a gas for transporting the second raw material gas, which is an inert gas. As the inert gas, for example, at least one of a rare gas such as argon and nitrogen can be applied.

[0203] Fig.18 FIG. 2 is a diagram schematically showing an example of the structure of the second gas supply unit 50 according to the fourth embodiment. Fig.18In the example of FIG. 5 , the second gas supply source 504 includes a gas supply pipe 5041 , a gas supply pipe 5042 , a bypass pipe 5043 , a switching unit 5044 , and a constant temperature bath 5058 .

[0204] The thermostatic tank 5058 is a sealed container that stores a liquid of the second raw material gas (hereinafter referred to as the second raw material liquid). The thermostatic tank 5058 includes a heat source that heats the second raw material liquid. This promotes the evaporation of the second raw material liquid, and the second raw material gas fills the space in the thermostatic tank 5058 to the vertical position above the second raw material liquid.

[0205] The upstream end of the gas supply pipe 5041 is connected to the thermostatic bath 5058. Specifically, the upstream end of the gas supply pipe 5041 opens vertically above the second raw material liquid in the thermostatic bath 5058. The downstream end of the gas supply pipe 5041 is connected to the upstream end of the second gas supply pipe 501.

[0206] The downstream end of the gas supply pipe 5042 is connected to the constant temperature chamber 5058. Fig.18 In the example of , the downstream end of the gas supply pipe 5042 is immersed in the second raw material liquid inside the thermostatic tank 5058. That is, the downstream end of the gas supply pipe 5042 opens in the second raw material liquid. The upstream end of the gas supply pipe 5042 is connected to the carrier gas supply source 5049. The carrier gas supply source 5049 includes a storage portion (not shown) for storing the carrier gas.

[0207] The upstream end of the bypass pipe 5043 is connected to the middle of the gas supply pipe 5042 , and the downstream end of the bypass pipe 5043 is connected to the upstream end of the second gas supply pipe 501 .

[0208] The switching unit 5044 is controlled by the control unit 9 to switch between the first connection state and the second connection state described below. The first connection state is a connection state in which the carrier gas from the carrier gas supply source 5049 is supplied to the upstream end of the second gas supply pipe 501 through the gas supply pipe 5042, the constant temperature tank 5058 and the gas supply pipe 5041. In the first connection state, the carrier gas flows into the interior of the constant temperature tank 5058. Therefore, the second raw material gas and the carrier gas in the constant temperature tank 5058 flow into the upstream end of the second gas supply pipe 501 through the gas supply pipe 5041. Therefore, in the first connection state, the second raw material gas and the carrier gas are supplied to the fluid head 3 through the second gas supply pipe 501. Therefore, the second raw material gas and the carrier gas flow out from the plurality of second outlets 6c of the fluid head 3 to the first main surface of the substrate W.

[0209] The second connection state is a connection state in which the carrier gas from the carrier gas supply source 5049 is supplied to the upstream end of the second gas supply pipe 501 through the bypass pipe 5043. In the second connection state, the carrier gas detours in the constant temperature bath 5058 and flows into the upstream end of the second gas supply pipe 501. Therefore, in the second connection state, the second raw material gas is not supplied to the fluid head 3, and the carrier gas is supplied to the fluid head 3. Therefore, only the carrier gas flows out from the plurality of second outlets 6c of the fluid head 3 toward the first main surface of the substrate W.

[0210] exist Fig.18 In the example of , the switching unit 5044 includes a valve 5045, a valve 5046, and a valve 5047. The valve 5045 is inserted into the gas supply pipe 5041, the valve 5046 is inserted into the portion between the bypass pipe 5043 and the constant temperature bath 5058 in the gas supply pipe 5042, and the valve 5047 is inserted into the bypass pipe 5043. By closing the valve 5047 and opening the valves 5045 and 5046, the switching unit 5044 can achieve a first connection state. By opening the valve 5047 and closing the valves 5045 and 5046, the switching unit 5044 can achieve a second connection state.

[0211] <Operation of film forming equipment>

[0212] Next, an example of the operation of the film forming apparatus 100 according to the fourth embodiment will be described. Fig.19 : is a flowchart showing an example of the operation of the film forming apparatus 100 according to the fourth embodiment. Fig.19 is a flowchart showing an example of a film forming method.

[0213] First, the substrate W is transported into the chamber 1 by an external transport device (step S1: loading process). Thus, the substrate W is placed on the susceptor 21 in a horizontal position. Next, the suction unit 7 sucks the gas in the chamber 1 to reduce the pressure in the chamber 1 (step S2: decompression process), and the heater 8 heats the substrate W (step S3: heating process). Next, the substrate holding unit 2 rotates the substrate W around the rotation axis Q1 (step S4: rotation process). The pressure adjustment of the chamber 1 by the suction unit 7, the temperature adjustment of the substrate W by the heater 8, and the rotation of the substrate W by the substrate holding unit 2 can be continuously performed until the film forming process is completed.

[0214] Next, the first gas supply unit 40 supplies the first raw material gas to the fluid head 3, the second gas supply unit 50 does not supply the second charge gas but supplies the carrier gas to the fluid head 3, and the plasma source 5 generates an electric field for plasma (step S5: plasma initial process). Specifically, first, the control unit 9 enables the switching unit 5044 to achieve the second connection state and opens the valve 502. As a result, the second gas supply unit 50 does not supply the second raw material gas but supplies the carrier gas to the fluid head 3. Therefore, the second raw material gas does not flow out from the multiple second outlets 6c of the fluid head 3, but the carrier gas flows out from the multiple second outlets 6c. In addition, the control unit 9 opens the valve 412 and the valve 422. As a result, the first gas supply unit 40 supplies the first raw material gas containing nitrogen and hydrogen to the fluid head 3. Therefore, the first raw material gas flows into the plasma chamber 4b of the fluid head 3. Since the control unit 9 enables the plasma source 5 to generate an electric field for plasma, the first raw material gas is plasmatized in the plasma chamber 4b. The active species generated by the plasmatization flow out from the multiple first outlets 4c.

[0215] After the operation of the plasma source 5 is just started, the plasma is not stable. That is, after the operation of the plasma source 5 is just started, the plasma may be generated locally instead of spatially uniformly in a plan view. Therefore, in the plasma initialization process, the second gas supply unit 50 does not supply the second raw material gas to the fluid head 3, but supplies the carrier gas to the fluid head 3. Therefore, in the plasma initialization process, even if the first raw material gas is started to be plasmatized, the formation of the target film on the first main surface of the substrate W does not start until the plasma is stabilized.

[0216] In addition, in the plasma initialization process, since the carrier gas flows out from the second outlet 6c of the fluid head 3, it is possible to suppress the active species flowing out from the first outlet 4c from flowing into the gas flow path 6b through the second outlet 6c. That is, it is possible to suppress unnecessary active species from mixing into the gas flow path 6b. If the active species mix into the gas flow path 6b, in the next process (film forming process) described later, when the second raw material gas flows into the gas flow path 6b, the second raw material gas reacts with the active species, and unnecessary substances may be precipitated on the inner wall of the second flow path member 6. Such precipitation will cause a change in the flow path area of ​​the gas flow path 6b, so it is not preferred.

[0217] On the other hand, in the fourth embodiment, the carrier gas flows out from the second outlet 6 c in the plasma initialization step, so that the flow channel area of ​​the gas flow channel 6 b can be suppressed from changing.

[0218] When a predetermined period has passed since the start of the plasma initialization process, the second gas supply unit 50 supplies the second raw material gas and the carrier gas to the fluid head 3 (step S6: film forming process). The predetermined period is a period longer than the period required for the stabilization of the plasma, and is, for example, set in advance. That is, the second gas supply unit 50 starts to supply the second raw material gas after the plasma is stabilized. More specifically, the control unit 9 enables the switching unit 5044 to achieve the first connection state. Thus, since the second gas supply unit 50 supplies the second raw material gas and the carrier gas to the fluid head 3, the second raw material gas and the carrier gas flow out from the plurality of second outlets 6c of the fluid head 3.

[0219] That is, in the film forming process, the fluid head 3 makes the active species flow out more uniformly from the plurality of first outlets 4c, and makes the second raw material gas flow out more uniformly from the plurality of second outlets 6c. The second raw material gas is thermally decomposed on the first main surface of the substrate W, and the components generated by the thermal decomposition react with the active species, thereby forming a target film on the first main surface of the substrate W.

[0220] In the film forming process, after the target film is formed with a predetermined film thickness, the control unit 9 ends the film forming process. Specifically, the control unit 9 closes the valve 412 and the valve 422 of the first gas supply unit 40 and the valve 502 of the second gas supply unit 50, and stops the operation of the plasma source 5. In addition, the control unit 9 stops the operation of the rotating mechanism 23, the heater 8, and the suction unit 7.

[0221] Next, the transport device carries out the substrate W from the chamber 1 (step S7 : carrying-out process). Specifically, the external transport device carries out the substrate W placed on the susceptor 21 from the chamber 1 .

[0222] As described above, in the fourth embodiment, the second gas supply unit 50 does not supply the second raw material gas but supplies the carrier gas to the fluid head 3 (plasma initialization process) during the prescribed period from the time point when the first raw material gas is supplied from the first gas supply unit 40 and the plasma source 5 is operated, and supplies the second raw material gas and the carrier gas to the fluid head 3 (film forming process) after the prescribed period has passed. Therefore, during the prescribed period when the plasma is unstable, the film forming process of the target film on the first main surface of the substrate W is not started, and the unevenness of the film thickness of the target film can be suppressed. In addition, during the prescribed period, since the carrier gas flows out from the second outlet 6c, the inflow of the active species flowing out from the first outlet 4c into the second outlet 6c can also be suppressed.

[0223] As described above, the film forming apparatus 100 is described in detail, but the above description is illustrative in all aspects, and the film forming apparatus 100 is not limited thereto. It should be understood that many modifications not shown can be conceived without departing from the scope of the present disclosure. The various structures described in the above embodiments and various variations can be appropriately combined or omitted as long as they do not contradict each other.

[0224] For example, in the above example, as the first raw material gas, a gas containing a group V element is applied, and as the second raw material gas, an organic metal gas containing a group III element is applied. Thus, the film forming device 100 can form a group III-V compound semiconductor film as a target film on the first main surface of the substrate W. However, it is not necessarily limited to this. For example, oxygen gas can also be applied as the first raw material gas, and silane gas can be applied as the second raw material gas. Thus, the film forming device 100 can form a silicon oxide film as a target film on the first main surface of the substrate W.

[0225] Description of Reference Numerals

[0226] 1: Chamber,

[0227] 100: Film forming device,

[0228] 21: loading platform (base),

[0229] 3, 3A: Fluid head,

[0230] 30: Cooling unit,

[0231] 40: first gas supply unit,

[0232] 4a: First flow entrance,

[0233] 4b: Plasma chamber,

[0234] 4c: First outflow port,

[0235] 5,5A: Plasma source,

[0236] 50: second gas supply unit,

[0237] 65: Conductive shielding parts (vertical pipe),

[0238] 6a: Second inlet,

[0239] 6b: Gas flow path,

[0240] 6b1: Flow path space,

[0241] 6b2: Through flow path,

[0242] 6c: Second outflow port,

[0243] 8: Heater,

[0244] R0: Overlapping area,

[0245] R1: Central area,

[0246] R2: Peripheral area,

[0247] W: Substrate.

Claims

1. A film forming device, wherein: have: Chamber, a mounting table, disposed in the chamber, for mounting a substrate, and a fluid head disposed in the chamber at a position facing the first main surface of the substrate mounted on the mounting table; The fluid head comprises: More than one first-class entrance, a plasma chamber into which the first raw material gas flows through the first inlet, a plasma source, which converts the first raw material gas into plasma in the plasma chamber, a plurality of first outflow ports connected to the plasma chamber and two-dimensionally dispersedly arranged in an overlapping region overlapping with the first main surface of the substrate in a plan view, for allowing active species generated by plasmatizing the first raw material gas to flow toward the first main surface of the substrate; One or more secondary inlets, a gas flow path into which the second raw material gas flows through the second inlet and is separated from the plasma chamber, and The plurality of second outlets are communicated with the gas flow path and are two-dimensionally dispersed in the overlapping region at positions different from those of the plurality of first outlets, so as to allow the second source gas to flow toward the first main surface of the substrate.

2. The film forming device according to claim 1, wherein: further comprising a heater for heating the substrate from the second main surface side of the substrate; The gas flow path has: a flow path space located on the side opposite to the mounting table with respect to the plasma chamber, into which the second raw material gas flows through the second inlet, and a plurality of through flow paths extending from the flow path space and penetrating the plasma chamber; A plurality of the second outflow ports are formed at front ends of the plurality of through flow paths, respectively.

3. The film forming device according to claim 2, wherein: At least a portion of the plasma source is disposed between the flow path space and the plasma chamber and is penetrated by the plurality of through flow paths.

4. The film forming device according to claim 3, wherein: The plasma source is a surface wave plasma source or a hollow cathode discharge plasma source.

5. The film forming device according to claim 3 or 4, wherein: The fluid head further includes a cooling portion, wherein the cooling portion cools the plasma source. The cooling unit is provided between the flow path space and the plasma source, and is penetrated by the plurality of through flow paths.

6. The film forming device according to any one of claims 2 to 4, wherein: The fluid head includes a conductive shield disposed between each of the plurality of through-flow passages and the plasma chamber.

7. The film forming device according to any one of claims 2 to 4, wherein: The opening area of ​​each of the plurality of second outflow ports is smaller than the flow path area of ​​each of the plurality of through flow paths.

8. The film forming device according to any one of claims 2 to 4, wherein: The plurality of second outflow ports are located on the mounting table side relative to the plurality of first outflow ports.

9. The film forming device according to any one of claims 1 to 4, wherein: The first inlet is formed at a side of the plasma chamber, Among the plurality of first outflow ports, an opening ratio of first outflow ports located in a central region in the overlapping region is larger than an opening ratio of first outflow ports located in a peripheral region outside the central region in the overlapping region.

10. The film forming apparatus according to any one of claims 1 to 4, wherein: The second inlet is formed on a side of the gas flow path. Among the plurality of second outflow ports, the opening ratio of the second outflow ports located in a central region in the overlapping region is larger than the opening ratio of the second outflow ports located in a peripheral region outside the central region in the overlapping region.

11. The film forming device according to any one of claims 1 to 4, wherein: The second inlet is formed at an upper portion of a central portion of the gas flow path.

12. The film forming device according to any one of claims 1 to 4, wherein: have: a first gas supply unit for supplying the first raw material gas to the fluid head, and a second gas supply unit for supplying the second raw material gas and an inactive carrier gas for conveying the second raw material gas to the fluid head; The second gas supply unit does not supply the second raw gas but supplies the carrier gas to the fluid head during a specified period starting from the time when the first gas supply unit supplies the first raw gas and the plasma source operates, and supplies the second raw gas and the carrier gas to the fluid head after the specified period.

13. The film forming device according to any one of claims 1 to 4, wherein: The first raw material gas contains a gas having a Group 15 element, The second raw material gas contains an organic metal gas having a Group 13 element.

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