WO2006095772A1 - Method of forming zinc oxide layer, zinc oxide layer forming apparatus and zinc oxide layer - Google Patents

Abstract

A method of forming a zinc oxide layer, in which a zinc oxide layer can be formed with high productivity with the use of a solid zinc compound; and a zinc oxide layer forming apparatus for use in the practice of the method. A solution of solid zinc compound [for example, Zn(DPM)2 + toluene] is vaporized by means of a vaporizer, and at least a vapor from the zinc compound solution is fed onto substrate (48) (for example, sapphire substrate with plane A as its main surface) heated in chamber (44) of CVD section. Thus, a zinc oxide layer is grown on the substrate (48).

Description

 Specification

 Zinc oxide layer forming method, zinc oxide layer forming apparatus, and zinc oxide layer

 [0001] The present invention relates to a method for forming a zinc oxide layer, more specifically, a method for forming a zinc oxide layer for growing a zinc oxide layer on a substrate, a zinc oxide layer forming apparatus used for the method, and the zinc oxide The present invention relates to an acid / zinc layer formed by the method for forming an acid / zinc layer using a layer forming apparatus.

 Background art

 [0002] The importance of a technique for forming an acid zinc layer on a substrate is increasing. For example, there is a detailed description of the “Oxidized gallon” epitaxy layer in “Applied Physics”, No. 72 卷 No. 6 (2003), p. 705 to p. 710, “Recent Progress of ZnO Epitaxy Layers”. .

[0003] However, here, we will explain in detail the importance of the surface power that greatly contributes to the production of blue light-emitting diodes.

[0004] Blue light-emitting diodes can be used together with existing green light-emitting diodes and red light-emitting diodes to constitute means for emitting the three primary colors of light. This is because the wavelength of the light to be emitted is short, so that the spot diameter of the light can be reduced, and for example, the storage capacity when recording information on a DVD or the like can be significantly increased.

[0005] Furthermore, the blue light generated from the blue light emitting diode emits light when it hits the phosphor, and has a light emission efficiency that is significantly better than incandescent and fluorescent lamps and has a long life. This leads to energy saving on a national and international scale.

[0006] By the way, in the past, a blue light emitting diode has a GaN (gallium nitride) layer formed on the main surface of a sapphire substrate having a C surface as a main surface, and the formed GaN layer is used as a main film. It was manufactured by the method of forming by doing.

However, this conventional technique has a problem that, first of all, when manufacturing a wafer of a sapphire substrate having a C surface as a main surface, it is difficult to obtain a large wafer. In particular,

About 100 mm is the maximum wafer diameter that can be obtained in practice. And the diameter of the wafer is small It is difficult to increase the productivity of the product, which makes it difficult to provide a low-cost blue light-emitting diode, and this problem cannot be overlooked.

Second, in order to grow a GaN film, a large amount of hydrogen gas H and ammonia gas NH are supplied.

 twenty three

 This requires exhaust gas treatment, which is a serious problem that cannot be overlooked both in terms of safety and economy, and is a major factor in increasing costs.

 [0009] On the other hand, there is a technique in which an oxide zinc epitaxy layer is formed on a sapphire substrate, and a blue light emitting diode is formed using the formed layer as a main film.

 [0010] In this technique, an oxide-zinc epitaxy layer is formed on a main surface of a sapphire substrate having an A surface as a main surface. A wafer of a sapphire substrate having an A surface as a main surface is described above. It has the advantage that it can be easily made larger than a sapphire substrate wafer with the C-plane as the main surface. Specifically, it is possible to obtain a wafer with a diameter of 300 mm with the current semiconductor manufacturing technology. Needless to say, this greatly contributes to the improvement of product productivity.

 [0011] By the way, there are MBE method and CVD (Chemical Vapor Deposition) method as the formation method of zinc oxide epitaxy layer. MBE method evaporates the raw material in the form of molecules under ultra-high vacuum, and evaporates it This is a physical method of depositing a thin film on a heated substrate to form a thin film, but because the substrate size is slow and the substrate size is small, mass productivity is low, and the ultra-high vacuum equipment is very expensive. It is not suitable for industrial use to manufacture products in large quantities.

 [0012] In contrast, the CVD method is capable of growing an oxide-zinc epitaxy layer vapor-phase chemically and is excellent in mass productivity with a high deposition rate. The material necessary for the formation of the layer is a vaporized zinc compound, such as zinc oxide, which is non-toxic as is apparent from its use as an anti-inflammatory agent. Therefore, there is no problem at all in terms of safety and economy.

 [0013] The above is one of the usefulness of the technique for forming an oxide zinc epitaxy layer on a substrate by CVD. Of course, there are a wide variety of other useful applications.

[0014] However, the CVD method requires supplying a chemical raw material gas to be a thin film onto a heated substrate, but there is no gaseous zincy compound at room temperature. Zinc compounds are readily available forces All are liquids or solids at room temperature. Liquid zinc compound The substances dimethylzinc and jetylzinc are water-inhibiting compounds that react violently with water and ignite, and are difficult to handle in large quantities.

[0015] Of course, it is impossible to perform vapor phase growth (CVD) using a solid as a gas for forming a CVD film by ordinary CVD technology.

 Non-Patent Document 1: “Applied Physics”, No. 72-6 (2003) pp. 705-710 “Recent Progress of ZnO Epitaxy”

 Disclosure of the invention

 Problems to be solved by the invention

[0016] However, recently, the inventor of the present application has developed a technical capability of performing vapor phase growth using a solid as a gas for forming a CVD film. Has been.

[0017] Therefore, the inventor of the present application has come up with the idea of using the technique to form an acid zinc layer. The inventor further sought a method for forming a zinc oxide layer optimal for forming a zinc oxide layer and a zinc oxide layer forming apparatus used for the implementation under the idea.

[0018] The present invention has been made as a result of the search.

 That is, the present invention provides a method for forming a zinc oxide layer capable of forming a zinc oxide layer with high productivity while using a solid zinc compound, and a zinc oxide layer forming apparatus used for the method. The purpose is to provide.

 Means for solving the problem

[0020] The method for forming an acid-zinc layer according to claim 1 is characterized in that a solid zinc-containing compound solution [for example, Zn (DP M) + toluene] is vaporized with a vaporizer, and at least the zinc-containing compound is formed. The vaporized solution

2

 A zinc oxide layer is grown on a heated substrate (for example, a sapphire substrate whose main surface is a c-plane or a silicon semiconductor substrate).

[0021] A method for forming a zinc oxide layer according to claim 2 is the method for forming a zinc oxide layer according to claim 1, wherein an oxidizing gas is supplied to the vaporizer and the zinc compound supplied onto the substrate is supplied. A feature is that an acid zinc layer is grown on the substrate by vaporizing the material solution and the acid gas. [0022] A method for forming a zinc oxide layer according to claim 3 is the same as the method for forming a zinc oxide layer according to claim 1, wherein an oxidizing gas is supplied onto the substrate to which the vaporized zinc compound solution is supplied. It is characterized by growing an oxide zinc layer on the substrate by supplying.

 [0023] A method for forming a zinc oxide layer according to claim 4 is the method for forming a zinc oxide layer according to claim 1, 2 or 3, wherein the substrate is placed in a certain range (for example, 200 to 650 ° C). When heated to a temperature, a zinc oxide layer on the surface [thickness, for example, 20 to 2000A (in the present specification, A is referred to as ondastroum. Originally, angstrom has a small circle on A. The force represented by the symbol is not usable, so it is replaced by A.;)] is formed, and then the substrate is heated to a temperature higher than the above range and in the range (eg 400-1100 ° C.). Further, an acid zinc layer (thickness 1000 to 30000A) is further formed on the acid zinc layer.

 [0024] The method for forming a zinc oxide layer according to claim 5 is the method for forming a zinc oxide layer according to claim 4, wherein the surface of the substrate is formed before the zinc oxide layer is formed on the surface of the substrate. It is characterized by being subjected to oxygen baking treatment.

 [0025] The acid-zinc layer forming device according to claim 6 receives at least the solid zinc-containing compound solution and the carrier gas through the valve, and the nozzle tip that ejects the received substance from the tip end thereof. A vaporizer for projecting into a vaporizing chamber having an inner diameter that is significantly wider than the inner diameter of the rod, and vaporizing the substance ejected from the tip of the nozzle in the vaporizing chamber, and a substrate holding section for heating and holding the substrate inside the chamber And a CVD unit that receives a gas supplied by at least the vaporizer force and grows a zinc oxide layer on the substrate holding unit by CVD (Chemical Vapor Deposition). Features.

[0026] The acid-zinc layer of claim 7 receives at least a zinc-containing compound solution and a carrier gas through a valve, and the tip of a nozzle that ejects the received substance is more noticeable than the inner diameter of the nozzle. A vaporizer that protrudes into the vaporization chamber having a wide inner diameter and receives the fine particle or mist-like substance ejected from the nozzle tip force in the vaporization chamber, and a substrate holding portion that holds the substrate inside the chamber A zinc oxide layer forming apparatus comprising: a CVD unit that receives at least a gas supplied from the vaporizer and that causes CVD of an oxide zinc layer on the substrate on the substrate holding unit. Use, vaporize the zinc compound solution in the vaporizer, At least, a gas obtained by vaporizing a solution of the zinc-containing compound is supplied onto the substrate on the substrate holding portion, thereby being formed on the substrate.

 [0027] The acid-zinc layer of claim 8 receives at least a zinc-containing compound solution and a carrier gas through a valve, and the tip of the nozzle that ejects the received substance is more conspicuous than the inner diameter of the nozzle. A vaporizer that protrudes into the vaporization chamber having a wide inner diameter and receives the fine particle or mist-like substance ejected from the nozzle tip force in the vaporization chamber, and a substrate holding portion that holds the substrate inside the chamber A zinc oxide layer forming apparatus comprising: a CVD unit that receives at least a gas supplied from the vaporizer and that causes CVD of an oxide zinc layer on the substrate on the substrate holding unit. A gas containing a zinc compound solution is vaporized in the vaporizer, and at least a gas obtained by vaporizing the zinc compound solution is heated on a temperature within a certain range on the substrate holding unit. Formed on this substrate by supplying to A first zinc oxide layer and a second oxide zinc layer formed on the first oxide zinc layer by heating the substrate to a temperature in a range higher than the range. It is characterized by having a laminated structure.

 [0028] The zinc oxide layer forming apparatus according to claim 9 is a zinc oxide layer forming apparatus including a vaporizer that supplies a gas obtained by vaporizing a zinc compound solution into a chamber. A carrier gas passage through which a carrier gas flows toward the outlet, a zinc compound solution passage for supplying the zinc compound solution to the carrier gas passage, and an outlet of the carrier gas passage. A vaporizing chamber for vaporizing the zinc compound solution supplied from the compound solution flow path, the carrier gas flow path supplying a carrier gas pipe to which the carrier gas is supplied, and the carrier gas pipe force supplying the carrier gas A nozzle for supplying the zinc compound solution in the form of fine particles or mist in a carrier gas and supplying it to the vaporizing chamber, and the vaporizing chamber is dispersed in the carrier gas. Characterized in that it comprises a heating means for heat vaporizing zinc I 匕合 product solution was.

[0029] In the method of forming an acid / zinc layer according to claim 10, the oxide / zinc layer is formed on the substrate in the chamber by supplying a gas obtained by vaporizing the zinc compound solution to the chamber. A carrier gas supply step of supplying the carrier gas to the chamber by flowing the carrier gas from the inlet to the outlet of the carrier gas flow path in the method of forming the zinc oxide layer; A zinc compound solution supplying step for supplying the zinc compound solution to the carrier gas channel, and the zinc compound solution is dispersed in the carrier gas in the form of fine particles or mist in the carrier gas channel, A vaporization chamber supply step for supplying to a vaporization chamber provided at an outlet of the carrier gas flow path; and a vaporization step for heating and vaporizing the zinc compound solution by a heating means of the vaporization chamber in the vaporization chamber. It is characterized by that.

 [0030] In the method of forming an acid / zinc layer according to claim 11, the oxide / zinc layer is formed on the substrate in the chamber by supplying a gas obtained by vaporizing the zinc / compound solution to the chamber. In the method for forming the zinc oxide layer, a carrier gas supply step for supplying a carrier gas to the chamber by flowing a carrier gas from an inlet to an outlet of the carrier gas channel; A zinc compound solution supplying step for supplying the zinc compound solution, and the zinc compound solution are dispersed in the carrier gas in the form of fine particles or mist in the carrier gas flow path, so that the flow in the carrier gas flow path is reduced. A vaporizing chamber supplying step for supplying to a vaporizing chamber provided at the outlet; a vaporizing step for heating the zinc compound solution in the vaporizing chamber by a heating means of the vaporizing chamber; A first oxide / zinc layer forming step for forming a first oxide / zinc layer with the gas vaporized in the vaporization step on the substrate; and heating the substrate to a higher temperature to form the first oxide / zinc layer. And a second zinc oxide layer forming step of forming a second acid zinc layer on the acid zinc layer.

 [0031] In the zinc oxide layer forming method of claim 12, in the first zinc oxide layer forming step, the substrate is heated to a temperature of 200 to 650 ° C to form the first zinc oxide layer, The second zinc oxide layer forming step is characterized in that the substrate is heated to a temperature of 400 to 1100 ° C. to form a second zinc oxide layer on the first zinc oxide layer.

 The invention's effect

 [0032] According to the method for forming an acid-zinc layer according to claim 1, a zinc-containing compound solution [eg, Zn (DPM) + toluene

 2] is vaporized by a vaporizer, and at least a solution obtained by vaporizing the zinc compound solution is supplied onto a heated substrate (for example, a sapphire substrate having a c-plane main surface or a silicon semiconductor substrate). Thereafter, it is possible to form a zinc oxide layer on the substrate by oxidizing.

[0033] Therefore, the zinc oxide layer is formed by CVD even though the zinc compound is solid. It is possible to

 [0034] According to the method for forming a zinc oxide layer according to claim 2, in the method for forming a zinc oxide layer according to claim 1, an oxidizing gas is supplied to the vaporizer. An acid zinc layer can be formed on the substrate with the zinc of the zinc compound mixed and supplied.

 Therefore, it is possible to form a zinc oxide layer by CVD even though the zinc compound is solid.

 [0036] According to the method for forming a zinc oxide layer according to claim 3, in the method for forming a zinc oxide layer according to claim 1, an oxidizing gas is supplied onto the substrate. An acid zinc layer can be formed on the substrate by the supplied zinc of the zinc compound.

 [0037] Therefore, it is possible to form a zinc oxide layer by CVD even though the zinc compound is solid.

 [0038] According to the method for forming a zinc oxide layer of claim 4, a zinc oxide layer (referred to as "first oxide zinc layer" for convenience) is formed on the surface of the substrate, and then the substrate Is heated to an appropriately higher temperature to further form an acid zinc layer (referred to as a “second zinc oxide layer” for convenience) on the first oxide zinc layer, and is affected by the substrate. Without this, the second zinc oxide layer can be grown.

 [0039] According to the method of forming a zinc oxide layer of claim 5, in the method of forming a zinc oxide layer of claim 4, the surface of the substrate is formed before the zinc oxide layer is formed on the surface of the substrate. Since the substrate is subjected to oxygen baking, the surface of the substrate can be made better. Therefore, the second oxide zinc layer can be grown without being affected by the substrate.

[0040] According to the acid / zinc / zinc layer forming apparatus of claim 6, the solid zinc compound solution and the carrier gas are received through the valve, the vaporizer for vaporizing the solution, and the supply of the gas from the vaporizer are received. Since it has a CVD part that grows a CVD film on the substrate on the CVD substrate holding part, the gas from the vaporizer is introduced into the CVD part and then oxidized to hold it in the substrate holding part in the CVD part. A zinc oxide layer can be formed on the substrate. [0041] Therefore, it is possible to form a zinc oxide layer by CVD even though the zinc compound is solid.

 [0042] According to the zinc oxide layer of claim 7, the zinc oxide layer forming device of claim 6 is used, the zinc compound solution is vaporized by the vaporizer of the device, and at least the solution of the zinc compound is vaporized. Since the formed gas is supplied onto the substrate on the substrate holding part, it is formed on this substrate, so that it can be easily formed by CVD even though the zinc compound is solid.

[0043] According to the zinc oxide layer of claim 8, the zinc oxide layer forming device of claim 6 is used, the zinc compound solution is vaporized by the vaporizer of the device, and at least the solution of the zinc compound is vaporized. By supplying the converted gas onto the substrate heated to a certain temperature range on the substrate holding portion, the first zinc oxide layer formed on the substrate and the substrate are moved beyond the range. Since the laminated structure is formed by the second oxide / zinc layer formed on the first oxide / zinc layer by heating to a high temperature range, the second oxidation is less affected by the substrate. It is possible to grow a zinc layer.

 According to the zinc oxide layer forming apparatus of claim 9, the zinc compound solution is instantaneously atomized by the high-speed carrier gas flow, and the zinc compound solution is easily vaporized by the heat of the heating means. Thus, it is difficult to vaporize, and even a zincy compound solution obtained by dissolving the zincy compound in a solvent can be easily vaporized in the vaporization chamber. Thereby, an acid zinc layer made of a zinc compound can be formed.

 According to the method for forming a zinc oxide layer of claim 10, the zinc compound solution is vaporized by a vaporizer, and the gas vaporized from the zinc compound solution is supplied onto the substrate on the substrate holding part. Thus, since the zinc oxide layer is formed on this substrate, it can be easily formed by the CVD method even though the zinc compound is solid.

[0045] According to the method for forming the zinc oxide layer according to claim 11, the zinc compound solution is vaporized by a vaporizer, and the gas vaporized from the zinc compound solution is deposited on the heated substrate on the substrate holding unit. By supplying, the first zinc oxide layer formed on the substrate and the second oxide layer formed on the first oxide zinc layer by heating the substrate to a higher temperature.匕 Because it has a laminated structure with a zinc layer, the second zinc oxide layer can be grown without being affected by the substrate. it can.

 [0046] According to the method for forming a zinc oxide layer according to claim 12, in the method for forming a zinc oxide layer according to claim 11, the first zinc oxide layer formed on the substrate and the substrate at a higher temperature. And the second oxide zinc layer formed on the first oxide zinc layer was formed into a laminated structure, so that the second oxide zinc was surely not affected by the substrate. Can grow layers Brief description of the drawings

FIG. 1 is a configuration diagram showing a zinc oxide layer forming apparatus according to a first embodiment of the present invention.

 FIG. 2 is a configuration diagram showing an apparatus for forming a zinc oxide layer according to a second embodiment of the present invention.

 FIG. 3 is a block diagram showing an apparatus for forming a zinc oxide layer according to a third embodiment of the present invention.

 FIG. 4 is a block diagram showing an acid zinc oxide layer forming apparatus according to a fourth embodiment of the present invention.

 [FIG. 5] (A) to (C) are cross-sectional views showing different examples of the method for forming the zinc oxide layer according to the present invention.

 FIG. 6 is a diagram showing the results of monitoring the change in carrier gas pressure over time when an oxide-zinc epitaxy layer is formed by a thermal CVD method.

 FIG. 7 is a diagram showing a temporal change in carrier gas pressure when a plasma CVD unit is used as the CVD unit.

 FIG. 8 is a diagram showing an example of an X-ray crystal diffraction result of a sample in which an acid-zinc zinc epitaxy layer having a thickness of about 1000 A is formed on the C surface of a sapphire substrate.

 FIG. 9 is a diagram showing another example of an X-ray crystal diffraction result of a sample in which an acid-zinc zinc epitaxy layer having a thickness of about 1000 A is formed on the A surface of a sapphire substrate.

 FIG. 10 is a view showing still another example of a result of X-ray crystal diffraction of a sample in which an acid / zinc zinc epitaxy layer having a thickness of about 500 A is formed on a silicon (111) substrate.

 FIG. 11 is a view showing still another example of an X-ray crystal diffraction result of a sample in which an oxide zinc oxide epitaxy layer having a thickness of about 500 A is formed on a silicon (100) substrate.

 FIG. 12 is a graph showing melting points and solubility in three types of solvents (toluene, butyrate, THF) for five types of zinc compounds (complexes).

[Fig.13] Zn (EDMDD)! / TG-DTA in an Ar (760Torr) atmosphere It is

 [Fig.14] TG—DTA in oxygen O (760 Torr) atmosphere for Zn (EDMDD)

 2 2

 [Fig.15] Zn (EDMDD)! / TG-DTA in an Ar (lOTorr) atmosphere

 2

 It is

 FIG. 16 is a diagram showing the TG characteristics of four types of substances that were studied for use as Zn complexes.

 FIG. 17 is a schematic view showing a detailed configuration of a vaporizer for CVD.

 FIG. 18 is a schematic diagram showing the overall configuration of a roller-type plasma oxide zinc layer forming apparatus according to a fifth embodiment.

 FIG. 19 is a schematic view showing an overall configuration of a roller-type plasma oxide zinc layer forming apparatus according to a sixth embodiment.

 FIG. 20 is a schematic view showing an overall configuration of a roller-type hot acid zinc salt layer forming apparatus according to a seventh embodiment.

 Explanation of symbols

[0048] 2 Vaporizer

 4, 4a, 4b, 4c CVD section

 6 nozzles,

 46 Substrate stage (substrate holder)

 48 substrate (wafer-like sapphire substrate with A side as the main surface)

 80 RF electrode

 100 shower plate

 200 Zinc oxide layer

 200a First zinc oxide layer (buffer layer)

 200b Second acid-zinc layer (original crystal layer)

 BEST MODE FOR CARRYING OUT THE INVENTION

The acid / zinc layer in the present invention may be an acid / zinc epitaxy layer, a zinc oxide polycrystalline layer, or a zinc oxide amorphous layer.

(1) Acid-zinc epitaxy layer Hereinafter, the acid zinc oxide epitaxy layer as the acid zinc layer will be described in detail with specific examples. In the present invention, a wafer-like sapphire substrate in which a sapphire is formed so that the main surface is the A-plane is suitable as a substrate on which an oxide zinc epitaxy layer is formed. This is the ability to obtain an acid-zinc epitaxy layer having crystallinity substantially continuous with the crystallinity of the surface of the sapphire substrate. Incidentally, the diameter of the wafer can be increased to 200-300 mm, for example.

 [0050] In the present invention, the substrate is not limited to a sapphire substrate, and a silicon semiconductor substrate can be used as a substrate, and an oxide zinc epitaxy layer can also be formed on the surface directly or via another thin film. For example, the zinc compound used as the material of the obtained oxide-zinc epitaxy layer is a force suitable for Zn (DPM), Zn (TMOD), Zn (IBPM), Zn (DIBM

 2 2 2

 ) Toluene is preferred as a solvent to dissolve it. Because toluene is hot

2

 This is because it has properties such as no wrinkle and high solubility even when entering the CVD part.

[0051] In addition, the supply of oxygen gas, which is indispensable for oxidizing zinc, is performed by using oxygen gas O as a carrier gas.

 2

 By supplying oxygen gas O to water vapor H 2 O or the like on the substrate inside the chamber from the outside of the chamber of the CVD unit.

 twenty two

 You can do more than just pay.

[0052] Although toluene is suitable as a solvent for dissolving zinc compounds, it is also suitable as a cleaning agent for cleaning the nozzle of the vaporizer. In other words, the nozzle tip of the vaporizer is clogged, for example, in about 10 hours, so when the degree of clogging is detected by the pressure in the nozzle and the pressure becomes higher than a preset value, the zinc oxide epitaxy is detected. It is preferable to stop the formation of the layer and supply a cleaning liquid to the nozzle instead of the zinc compound solution, thereby washing the tip of the nozzle. However, toluene is the optimum cleaning liquid. is there.

 [0053] It is necessary to supply a carrier gas for transporting the zinc compound to the nozzle of the vaporizer. As the carrier gas, nitrogen gas N, oxidizing gas O, or argon Ar is suitable.

 twenty two

 is there.

[0054] The formation of the acid-zinc epitaxy layer requires not only a zinc-containing compound as a material but also an oxidizing gas o, which can supply the acid gas o as a carrier gas. And as described above.

 (1 1) Example 1

 Hereinafter, the details of the present invention will be described based on illustrated embodiments.

 [0055] Fig. 1 is a configuration diagram showing an acid / zinc / zinc layer forming apparatus according to a first embodiment of the present invention. The zinc oxide epitaxy layer forming apparatus as the present zinc oxide layer forming apparatus is relatively small.

 In FIG. 1, 2 is a vaporizer, 4 is a CVD unit, and the present zinc oxide epitaxy layer forming apparatus is roughly constituted by the vaporizer 2 and the CVD unit. The nozzle 6 of the vaporizer 2 has an inner diameter of, for example, about 1. Omm (the inner diameter at the tip is about 0.3 mm), and is provided substantially vertically with the tip from which the gas is jetted downward. A carrier gas supply pipe 8 is located above the nozzle 6 and contains a carrier gas (for example, nitrogen gas N or acid gas O).

 2

 Or argon (Ar), and 10 is provided in the carrier gas supply pipe 8.

2

 Gas valve.

 [0057] 12 is a pressure gauge for detecting the pressure in the nozzle 6 and is provided for detecting the degree of clogging at the tip of the nozzle 6. In other words, when the present zinc oxide epitaxy layer forming apparatus is used, the tip of the nozzle 6 is clogged, and if the clogging exceeds a certain limit, normal gas supply becomes impossible, and normal CVD is not possible. Since it becomes possible, it is necessary to clean it, but the degree of the clogging is detected by the pressure gauge 12. This utilizes the principle that clogging can be detected by pressure because the pressure increases when the tip of the nozzle 6 is clogged.

 FIG. 6 shows the results of monitoring the temporal change in the carrier gas pressure when the zinc oxide epitaxy layer was formed by the thermal CVD method under the conditions shown in Table 1. In this case, the gas pressure hardly changes, that is, no clogging occurs. In Table 1, the chemical solution composition is Zn (DPM) 0.2 molZL, and the solvent is toluene.

 2

[0059] [Table 1]

In addition, FIG. 7 shows the conditions shown in Table 2 in which the plasma CVD part, which will be described later, is used as the CVD part. This shows the results of monitoring the change over time in the carrier gas pressure when the zinc halide epitaxy layer was formed. In this case, clogging has occurred, and it can be said that after about 800 seconds, it is necessary to stop and clean the CVD. In Table 2, the chemical solution composition is Zn (DPM) 0.2 mol ZL, and the solvent is toluene.

 2

[0060] [Table 2]

 A valve unit 14 controls the supply of chemicals and solvents to be supplied to the nozzle 6. 16 is a zinc compound, in this example, a solution cylinder for storing Zn (DPM) solution.

 2

 Toluene is used as the solvent. A solution cylinder with Zn (DPM) dissolved in toluene

 2

 The solution in 16 is pressurized with a pressurizing gas, for example, helium He, and supplied into the valve unit 14 through one valve of the valve unit 14.

 [0061] Reference numeral 18 denotes a cleaning liquid cylinder for storing a cleaning liquid, for example, toluene. The toluene in the inside is pressurized by a pressurizing gas, for example, helium He, and is supplied into the nozzle 6 through another valve of the valve unit 14. To be supplied.

 [0062] Reference numeral 20 denotes a vaporizing tube constituting the vaporizer 2, which has a remarkably larger inner diameter than the nozzle 6, is provided in a vertical direction, and the tip of the nozzle 6 enters the upper end portion thereof. The vaporizing tube 20 has a branching portion 22 that branches substantially horizontally at a portion closer to the top than the lower end. The lower end of the vaporizing pipe 20 communicates with the vacuum pipe 26 via the vent valve 24. The vacuum pipe 26 communicates with an exhaust vacuum pump 30 through an exhaust valve 28.

 [0063] 32 is a heater provided on the surface of the vaporizing tube 20, and heats it to about 250 ° C, for example.

[0064] 34 is a chamber body of the CVD unit 4, and 36 is a heater provided on the outer surface of the chamber body 34. A part of the chamber body 34 also covers a raw material intake unit (58) to be described later. This contributes to maintaining the inside of the raw material intake (58) at a temperature of about 250 ° C, for example. 38 is a chamber lid that covers the upper part of the chamber body 34, 40 is a quartz cover on the back surface of the chamber lid 38, and 42 is a chamber support that supports the chamber body 34 at its lower part. The chamber 44 and the chamber support 42 constitute a channel 44 that forms the main part of the CVD unit 4. Reference numeral 46 denotes a substrate stage (substrate holding unit) that supports the substrate 48 inside the chamber 44, and includes a heater 50. A substrate heater control unit 52 controls heating of the heater 50 of the substrate stage 46. 54 is a temperature sensor and 56 is a heater wiring.

 [0066] Reference numeral 58 denotes a tubular raw material intake portion formed integrally with the chamber main body 34, and communicates with the branching portion 22 of the vaporizing pipe 20 via the raw material supply valve 60. When opened, the inside of the chamber 44 communicates with the vaporizing tube 20. 62 is an acid gas supply port provided in the chamber body 34, and the acid gas (oxygen gas O or oxygen gas) is supplied through the acid gas supply port 62.

 2

V soot can supply water vapor (H 2 O) into the chamber.

 2

 [0067] 64 is a pressure gauge for measuring the pressure inside the chamber 44, 66 is an exhaust pipe for exhausting gas from the inside of the chamber 44, 68 is a trap provided in the exhaust pipe 66, and removes specific harmful components in the exhaust gas . Similarly, reference numeral 70 denotes a chamber exhaust valve provided in the exhaust pipe 66, and the exhaust pipe 66 is connected to the exhaust valve 28 via the chamber exhaust valve 70. Therefore, the gas inside the chamber 44 is exhausted by the vacuum pump 30 through the exhaust pipe 66.

 In this example, the substrate 48 is a wafer-like sapphire substrate formed so that the main surface is the A plane. When performing CVD, by operating the nozzle unit 14, the zinc compound solution in the solution cylinder 16 is pressurized with a pressurizing gas such as helium He and supplied into the nozzle 6, and the gas valve 10 Then, the carrier gas is supplied into the nozzle 6. The vent valve 24 is kept closed.

 [0069] The supplied zincy compound solution is vaporized (gasified) when the tip force of the nozzle 6 is also ejected into the vaporizing tube 20. Then, the zinc compound is sent into the chamber 44 through the opened raw material supply valve 60, and the zinc Zn is supplied on the substrate 48 through, for example, the oxidizing gas supply port 62. It reacts with the gas to become zinc oxide and deposits on the substrate 48.

 Note that the gas that has finished the reaction inside the chamber is sent to the vacuum pump 30 through the exhaust pipe 66 and exhausted.

[0071] The zinc oxide on the substrate 48 gradually grows while substantially inheriting the crystallinity of the surface of the substrate 48 (A surface of sapphire), and becomes an oxide-zinc epitaxy layer. And the thickness is a predetermined thickness When reaching (for example, 20 to: LOOOOA), the force on the substrate stage 46 in the chamber is also taken out of the substrate 48, another substrate 48 is set, and an acid-zinc epitaxy layer is grown on the surface.

 On the other hand, the pressure in the nozzle 6 is monitored by the pressure gauge 12.

[0073] If the pressure exceeds a predetermined reference value (for example, 0.275 MPa), the CVD is stopped and the nozzle is cleaned. Specifically, the valves 60 and 70 are closed, and the valve of the valve unit 14 for supplying the solution from the solution cylinder 16 into the nozzle 6 is also closed, and the cleaning liquid cylinder 18 is used for cleaning. Open the valve that allows toluene to pass through the nozzle 6 and also open the vent valve 24.

[0074] Then, the toluene in the cleaning liquid cylinder 18 is pressurized by the helium gas He, which is a pressurizing gas, and is supplied into the nozzle 6 and is vaporized when the tip force is ejected, thereby removing clogging. . The gas that contributed to the cleaning is exhausted from the vacuum pipe 26 by the vacuum pump 30. When the pressure value monitored by the pressure gauge 12 becomes lower than a predetermined value (for example, 0.15 MPa), the cleaning is terminated, the state of the oxide zinc epitaxy layer forming apparatus is switched to the state where CVD is performed, and the CVD To resume.

 (1 2) Example 2

 FIG. 2 is a block diagram showing a zinc oxide layer forming apparatus according to a second embodiment of the present invention. This embodiment is different from the embodiment shown in FIG. 1 only in that a plasma CVD portion 4a is used as the CVD portion, and the other points are common. Therefore, in FIG. 2, parts that are the same as those in FIG. 1 are given the same reference numerals, and descriptions of the common parts are omitted as appropriate.

 In FIG. 2, reference numeral 80 denotes an RF (Radio Frequency) application electrode provided in the chamber 44, and a heater 82 is built in the surface portion, and the surface portion is spaced apart and placed above the substrate stage 46. It is arranged as follows. The RF application electrode 80 is attached in a state where it is electrically insulated from the chamber lid 38 covering the chamber body 34 by an insulating material 84, and is also electrically connected to an external RF power source 88 through an external noise cut filter 86. An RF power supply voltage is received between the substrate stage 46 connected and electrically grounded, and plasma is formed.

Reference numeral 90 denotes a heater control unit that controls the heater 82 on the surface of the RF application electrode 80. [0077] Since the plasma CVD unit 4a shown in FIG. 2 forms plasma on the substrate 48, the temperature is lower (eg, 100 to 500 ° C.) than that in the normal CVD unit 4 as shown in FIG. Then, CVD can be performed.

 (1 3) Example 3

 FIG. 3 is a block diagram showing a zinc oxide layer forming apparatus according to a third embodiment of the present invention. In this embodiment, the raw material is supplied so that the substrate 48 on the substrate stage 46 can be directly showered, and the uniform film quality is obtained on the large-diameter wafer-like substrate. Although it has the advantage that an oxide-zinc epitaxy layer with a thickness can be formed, it has parts common to the embodiment shown in FIG. 1, and parts common to FIG. 1 in FIG. In addition, the description of the parts that have already been described will be omitted as appropriate.

In FIG. 3, reference numeral 20a denotes a vaporization pipe constituting the vaporizer 2, and the vaporization pipe 20 shown in FIG. 1 is the inside of the chamber 44 of the CVD section (4b) described later via the raw material supply valve 60. However, it is different in that it is designed to supply this upper force and communicate with the vacuum pipe 26 through the vent valve 24 through the branch 22a provided above the lower end. The same.

 [0079] Further, the basic configuration of the nozzle 6 is the same as that of Fig. 1, and since it has already been described, description thereof is omitted.

 [0080] Reference numeral 4b denotes a shower plate type CVD unit, and a shower plate 100 is provided in the chamber 44 thereof. This shower plate 100 has an internal space 102 for receiving the raw material gas from the raw material intake portion 58 inside, and a gas ejection hole 104 for ejecting the raw material gas supplied into the internal space 102 on the downward surface portion thereof. There are a large number of 104, 104, ....

 [0081] The shower plate 100 has a chamber so that the downward surface on which the gas ejection holes 104, 104, ... are disposed is parallel to the substrate stage 46 in the upward direction. It is attached to the lid 38.

[0082] 106 is a gas vessel, for example, receiving oxygen gas O as a carrier gas and receiving H 2 O for example.

 2 2 and supply it into the interior space 102 of the shower plate 100.

[0083] 108 is a shower plate heater provided on the upper surface of the shower plate 100, 110 is A control unit for controlling the shower plate heater, 112 is a temperature sensor, and 114 is a heater wiring.

 The shower plate heater 108 and other heaters 32 and 36 form an oxide zinc epitaxy layer on the substrate 48 at a temperature of 400 to 1000 ° C., for example.

 Note that reference numeral 116 denotes a chamber door formed in the chamber body 34, which is opened when the substrate 48 is taken in and out.

 According to the oxide-zinc epitaxy layer forming apparatus of the embodiment shown in FIG. 3, the source gas is supplied to the internal space 102 of the shower plate 100 that is opposed to the substrate stage 46 in the CVD unit 4b. In addition, since the gas blow holes 104, 104,... Are blown directly onto the substrate stage 46, it is possible to obtain an oxide dumbbell epitaxy layer having a uniform film quality and thickness on a wafer-like substrate 48 having a large diameter. . For example, an oxide zinc epitaxy layer can be formed on an 8-inch or 12-inch wafer-like substrate 48 without any trouble.

 (1 4) Example 4

 FIG. 4 is a block diagram showing a zinc oxide layer forming apparatus according to a fourth embodiment of the present invention. This embodiment is different from the embodiment shown in FIG. 3 in that an RF voltage is applied between the shower plate 100 and the ground (substrate stage 46) to form plasma on the substrate 48. It is different but common in other points. Therefore, parts common to FIG. 3 in FIG. 4 are denoted by the same reference numerals, or illustrations thereof are omitted, and overlapping descriptions in the specification are appropriately omitted.

 [0087] In FIG. 4, 4c is a shower plate type and plasma type CVD unit. An RF electrode 80 is formed on the upper surface of the shower plate 100 via an insulating material 120, and a shower plate heater 108 is formed on the upper surface thereof. Is provided! /

 The heating of the shower plate heater 108 is controlled by the heater control unit 110. 112 is a temperature sensor, and 114 is a heater wiring force. A noise cut filter 86 is interposed between the heater control unit 110 and the heater 108. This noise cut filter 86 is for preventing the RF voltage from entering the heater control unit 110.

[0089] The RF electrode 80 is made of, for example, aluminum, and is connected to an RF power source 88. In between, it receives RF voltage from its RF power supply 88.

[0090] According to such an acid-zinc epitaxy layer forming apparatus, uniform film quality and film thickness with respect to the large-diameter wafer-like substrate 48 of the acid-zinc epitaxy single-layer forming apparatus shown in FIG. In addition to being able to enjoy the effect of being able to form a lead oxide layer of oxygen, a plasma is applied on the substrate stage 46 by applying an RF voltage between the shower plate 100 and the ground. Therefore, it is possible to enjoy the effect that the acid / dumbbell epitaxy layer can be formed at a relatively low temperature, for example, 100 to 500 ° C.

(1 5) Example 5

 5 (A) to 5 (C) are cross-sectional views showing different examples of the method for forming the zinc oxide epitaxy layer of the present invention. Fig. 5 (A) shows a method in which only one oxide-zinc epitaxy layer 200 is formed on a wafer-like sapphire substrate (sapphire substrate) 48 formed so that the A-plane becomes the main surface. Show.

 The zinc oxide epitaxy layer 200 is formed by CV D under a high temperature of, for example, 400 to: L 100 ° C., and the thickness thereof is, for example, 1000 to 30000A.

 [0092] FIG. 5 (B) shows that the first acid-zinc epitaxy layer 200a is first formed as a buffer layer on the sapphire substrate 48, and is excellent in crystallinity as the original acid-zinc epitaxy layer. A method for forming the second oxide-zinc epitaxy layer 200b will be described.

 That is, since the lattice constant of the acid-zinc epitaxy layer 200 and the sapphire substrate 48 is not exactly the same, the portion of the acid-zinc epitaxy layer that is in direct contact with the sapphire substrate 48 is slightly different. In addition, the crystal in the vicinity thereof is slightly out of alignment with the original crystal of the acid-zinc epitaxy layer. Therefore, a first oxide / zinc epitaxy layer 20 Oa is formed as a noffer layer, and a second oxide layer is formed thereon as an original zinc oxide epitaxy layer on which, for example, a blue light emitting diode is formed. The zinc epitaxy layer 200b is formed.

[0094] The method for forming this oxide-zinc epitaxy layer will be specifically described. First, the first oxide-zinc epitaxy layer 200a (thickness is formed by CVD at a relatively low temperature of 200 to 650 ° C. For example, 20 to 2000 A) is formed, and then a second oxide zinc epitaxy layer 200b (thickness is 1000 to 30000 A, for example) is formed by CVD at a high temperature of 400 to L 100 ° C. Form [0095] In the method shown in FIG. 5C, the surface of the sapphire substrate 48 is formed on the surface of the sapphire substrate 48, for example, from 570 to L 100 before the formation of the first oxide-zinc epitaxy layer 200a in the method shown in FIG. Oxygen baking is performed at a temperature of ° C. As a result, it is possible to obtain a better acid-zinc epitaxy layer 200a, 200b.

 [0096] Each figure after FIG. 6 shows various data obtained in the process of carrying out the present invention. The data shown in each figure will be described below.

 [0097] Figs. 6 and 7 show the results of monitoring the temporal change in the carrier gas pressure when forming the force-oxide-epitaxy layer described above, and Fig. 6 shows the thermal CVD. The case by law is shown. In this case, the gas pressure hardly changes, that is, no clogging occurs.

 [0098] Fig. 7 shows the change over time in the carrier gas pressure when the plasma CVD part is used as the CVD part. In this example, when the pressure is about 275 MPa, clogging that should stop the CVD occurs. In this example, clogging that should stop CVD occurs after about 800 seconds. When the CVD is stopped, cleaning is performed with, for example, a gasified cleaning solution of toluene, and when the carrier gas pressure returns to a lower value such as 0.13 MPa, the CVD is resumed.

 [0099] In FIGS. 8 to 11, a zinc oxide epitaxy layer having a thickness of about 500A to 1000A is formed on a sapphire C-plane substrate, a sapphire A-plane substrate, a silicon (111) substrate, and a silicon (100) substrate. The X-ray crystal diffraction results of the sample are shown. The signal indicating the zinc oxide crystal is only the diffraction line of (0002) appearing around 34.4 ° and the diffraction line of (0004) appearing around 72.6 °, and no other exponential diffraction lines. From these data shown in FIGS. 8 to 11, it can be understood that the zinc oxide crystals grown on any substrate are completely C-axis oriented with respect to the substrate surface. The surface of the zinc oxide crystal was extremely flat and free from cloudiness.

 [0100] FIG. 12 is a graph showing melting points and solubility in three types of solvents (toluene, butyl acetate, THF) for five types of zinc compounds (complexes). In terms of melting point, 141 ° C Zn (DPM) and Zn (acac) are suitable for CVD of zinc oxide epitaxy layer.

twenty two

In other words, Zn (DPM) is preferable from the viewpoint of solubility in a solvent. [0101] In addition, among the three types of solvents that dissolve zinc compounds, toluene, butyl acetate, and THF, it can be said that toluene and THF are superior in terms of solubility. Soot is generated in the chamber of the CVD unit. However, it can be said that toluene having the following advantages is optimal, and among those selected in FIG. 12 as zinc compounds, it is preferable to use Zn (DPM) as the solvent and toluene as the solvent.

 2

 It is the best.

 [0102] However, for example, a Zn complex is not necessarily limited to Zn (DPM). Fig. 13 ~

 2

 Figure 15 shows Zn (EDMDD) in a Zn complex that is chemically stable at room temperature! / TG-DT

 2

 An A chart is shown, FIG. 13 shows an argon Ar (760 Torr) atmosphere, and FIG. 14 shows an oxygen O (76

 2

In the case of an OTorr atmosphere, FIG. 15 shows the case of an argon Ar (lOTorr) atmosphere.

[0103] Figure 13 shows that Zn (EDMDD) is approximately 100 at approximately 280 ° C in an argon Ar (760 Torr) atmosphere.

 2

 Figure 14 shows that about 300 ° C in the same oxygen O (760 Torr) atmosphere.

 2

 It shows that about 100% evaporates. Note that the evaporation temperatures of 280 ° C and 300 ° C are 20%.

The difference in ° C is thought to be due to the difference in sample amount.

[0104] Fig. 15 shows that the same argon Ar (lOTorr) atmosphere evaporates by about 100% at 200 ° C. The difference in the sublimation temperature between 300 ° C and 200 ° C at 100 ° C is considered to be due to the difference in pressure between 760Torr and lOTorr.

[0105] Note that when forming a zinc oxide epitaxy layer using Zn (DPM) and oxygen, a reduced pressure gas is used.

 2

 It can be said that the temperature of the chemical tube (pressure lOTorr) should be set to 210 to 220 ° C. In addition, Fig. 14 shows that there is no major problem even if oxygen is added in addition to the inert gas alone as the carrier gas flowing through the vaporization tube.

[0106] Fig. 16 shows the TG characteristics of the four types of substances that the inventors of the present application have studied using as a Zn complex for the formation of an acid-zinc epitaxy layer. TMO D), Zn (DPM), Zn (IBPM), Zn (DIBM)] are not much different.

 2 2 2 2

 [0107] Therefore, it can be said that any of these Zn complexes can be used to form an acid-zinc epitaxy layer.

 (1 6) Example 6

Next, the detailed configuration of the CVD vaporizer 2 as a vaporizer will be described below. The CV D vaporizer 2 includes a vaporization mechanism 320. In this case, the vaporizer for CVD 2 uses the vaporization mechanism 32 The carrier gas is always supplied to the reaction chamber 44 as a chamber by 0, and almost all of the predetermined amount of zinc compound solution supplied from the zinc compound solution supply mechanism 321 is reliably vaporized by the vaporization mechanism 320 and reacted. The chamber 44 is configured to be supplied.

 [0108] (1— 6— 1) Composition of vaporization mechanism

 First, the vaporization mechanism 320 will be described. As shown in FIG. 17, in the vaporization mechanism 320, a carrier gas flow path 322 for supplying various carrier gases such as nitrogen gas and argon into the reaction chamber 44 is formed by a carrier gas pipe 323 and an orifice pipe 324 as a nozzle. Then, a vaporization section 325 as a vaporization chamber is formed at the tip of the orifice pipe 324 (that is, the outlet 333 of the carrier gas flow path 322).

 [0109] In practice, the vaporization mechanism 320 is configured such that the base end of the carrier gas supply pipe 323 (that is, the inlet of the carrier gas flow path 322) is connected to a supply mechanism (not shown) for supplying a carrier gas. At the same time, the distal end 330 of the carrier gas supply pipe 323 is connected to the base end 331 of the orifice pipe 324, whereby high-speed carrier gas can be supplied from the carrier gas supply pipe 323 to the orifice pipe 324.

 [0110] Incidentally, between the base end of the carrier gas supply pipe 323 and the supply mechanism, an N supply valve and

 2

 A mass flow controller (not shown) is provided. The carrier gas supply pipe 323 is attached with a pressure transducer 332 as a pressure gauge.

It should be noted that the pressure transducer 332 accurately measures the carrier gas pressure in the carrier gas supply pipe 323 and its fluctuation and constantly monitors it while recording it. The pressure transducer 332 transmits an output signal having a signal level corresponding to the pressure level of the carrier gas to a control unit (not shown).

 [0112] The pressure result of the carrier gas can be displayed on the display unit (not shown) by force based on the output signal so that the operator can monitor it. This allows the operator to monitor the clogging of the carrier gas flow path 322 based on the pressure result.

 Here, the inner diameter of the carrier gas supply pipe 323 is selected to be larger than the inner diameter of the orifice pipe 324 so that the flow velocity of the carrier gas supplied from the carrier gas supply pipe 323 to the orifice pipe 324 can be further increased. It is composed.

[0114] The orifice tube 324 is arranged in a vertical direction, and a convex portion having a trapezoidal cone shape at the tip 333 thereof. 334 is provided, and a fine hole 335 is provided at the top of the convex portion 334. In this way, in the orifice pipe 324, by providing the convex portion 334 at the tip, an inclined surface 334a is formed around the outer periphery of the spray port 336, which is the tip of the pore 335, and the residue is thereby formed in the spray port 336. This makes it difficult to collect and prevents the spray port 336 from being clogged.

 Incidentally, in the case of this embodiment, it is preferable that the apex angle Θ of the convex portion 334 is formed at an acute angle of 45 ° to 135 °, particularly 30 ° to 45 °. It is possible to prevent the spray port 336 from being clogged with zinc compound.

 [0116] The pore 335 of the spray port 336 is selected so that the inner diameter thereof is smaller than the inner diameter of the orifice pipe 324, and the flow velocity of the carrier gas supplied from the orifice pipe 324 to the pore 335 is further increased. Has been. Here, the tip of the pore 335 can be disposed so as to protrude into the internal space 338 of the vaporizing section 325 by inserting the convex portion 334 of the orifice pipe 324 into the proximal end 337 of the vaporizing section 325.

 [0117] The orifice pipe 324 is connected to a plurality of (in this case, for example, five) connecting pipes 340a to 340e from the base end 331 to the convex portion 334 in connection with the powerful configuration. Each of the connecting pipes 340a to 340e is provided with a zinc compound solution supply mechanism 321 described later. Thus, the orifice pipe 324 is configured such that a predetermined amount of zinc compound solution can be supplied from the zinc compound solution supply mechanism 321 via the connection pipes 340a to 340e.

 In this case, for example, the orifice pipe 324 applies a carrier gas flowing at a high speed to the zinc compound solution supplied from the connection pipe 340a, and disperses the zinc compound solution in the carrier gas in the form of fine particles or mist. In this state, it is configured to spray at a high speed (230 mZ seconds to 350 mZ seconds) through the pores 335 into the vaporization section 325.

 In the case of this embodiment, the orifice pipe 324 is selected to have an inner diameter of, for example, about Φ 1. Omm, and a longitudinal length extending in the vertical direction is selected to be about 100 mm. The inner diameter is selected to be about Φ Ο. 2 to 0.7 mm, and the diameter is reduced from the base end 331 to the pore 335, so that the carrier gas can be made high-speed inside. .

Here, the vaporizing section 325 connected to the orifice pipe 324 is tubular, and is arranged in the vertical direction similarly to the orifice pipe 324. As shown in FIG. By selecting significantly larger than the diameter, the pressure in the vaporization section 325 is formed to be smaller than the pressure in the orifice pipe 324!

[0121] In this way, in the vaporization section 325, since a large pressure difference is provided between the vaporization section 325 and the orifice pipe 324, the zinc compound solution and the carrier gas can be rapidly discharged from the orifice pipe 324 (for example, from 230 mZ sec. It is ejected at 350 mZ seconds) and can be expanded in the internal space 338.

 [0122] Actually, in the case of this embodiment, the pressure in the vaporization section 325 is selected to be about lOTorr, for example, whereas the pressure in the orifice pipe 324 is selected to be about 500 to 1000 Torr, for example, A large pressure difference is provided between the portion 325 and the orifice tube 324.

 Incidentally, the pressure of the carrier gas after the flow rate control is a force that increases or decreases depending on the carrier gas flow rate, the solution flow rate and the size of the pore 335. Finally, the size of the spray port 336 is selected and the carrier gas pressure is increased. It is preferable to control to 500 to 1000 Torr.

 [0124] In addition to this, on the outer periphery of the vaporizing section 325, a heater 342 as a heating means is attached between the base end 337 and the front end (that is, the connection portion with the reaction chamber 44). Thus, the vaporizing section 325 can be heated to about 270 ° C., for example. In the case of this embodiment, since the base end 337 of the vaporizing section 325 is formed in a substantially hemispherical shape, the base end 337 side can be uniformly heated by the heater 342. ing.

 [0125] The vaporizing unit 325 is configured to instantaneously vaporize the zinc compound solution dispersed and atomized by the high-speed carrier gas flow in the orifice pipe 324 by the heater 342. Has been. At this time, when the zinc compound solution is mixed in the orifice tube 324, the time until spraying in the force vaporizing section 325 is extremely short (preferably within 0.1 to 0.002 seconds). It is preferable. The zinc compound solution becomes fine immediately after being dispersed in the orifice pipe 324 by the high-speed carrier gas flow, and is instantly vaporized in the vaporizing section 325. Moreover, the phenomenon of vaporizing only the solvent is suppressed.

 [0126] By spraying the zinc compound solution and carrier gas onto the vaporizer 325 at a high speed, the mist size is reduced (the mist diameter is 1 m or less), and the evaporation area is increased. The evaporation rate can be increased. If the fog size is reduced by an order of magnitude, the evaporation area will increase by an order of magnitude.

It should be noted that the mist ejected from the spray port 336 does not collide with the inner wall of the vaporizing section 325 so that the spray port 336 It is preferable to design the angle and the size of the vaporization part 325. This is because when the mist collides with the inner wall of the vaporizing section 325, it adheres to the wall surface, the evaporation area decreases by an order of magnitude, and the evaporation rate decreases. In addition, when the mist has adhered to the vaporization section 325 wall for a long time, there is a force that may be converted into a compound that does not evaporate due to thermal decomposition.

 [0128] In this case, the vaporization unit 325 can lower the sublimation temperature of the zinc compound in each of the zinc compound solutions by reducing the pressure inside, and as a result, the heater 342 The zinc compound solution can be easily vaporized with heat from the heat!

 In this way, the vaporizing unit 325 vaporizes the zinc compound solution, supplies the raw material gas to the reaction chamber 44, and forms an acid zinc epitaxy layer by the CVD method in the reaction chamber 44. It is made to get.

 [0130] The base end 337 of the vaporizing section 325 has a heat insulating material 343 between the vaporizing section 325 and the heat insulating material 343 so that heat from the vaporizing section 325 is hardly transmitted to the orifice pipe 324. It is configured! Incidentally, the proximal end 337 of the vaporizing section 325 is hermetically sealed by an O-ring 344! /. Further, a heat insulating material 346 is also provided in the fastening member 345 that connects the orifice pipe 324 and the vaporizing section 325.

 Incidentally, it is preferable that the mist sprayed from the pores 335 does not wet the inner wall of the vaporizing section 325. The reason is that the evaporation area is reduced by orders of magnitude on wet walls compared to fog. That is, a structure in which the inner wall of the vaporizing section 325 is not dirty at all is preferable. In addition, the vaporization part 325 wall is preferably mirror-finished so that the dirt on the inner wall of the vaporization part 325 can be easily evaluated.

 (1-6-2) Structure of zinc compound solution supply mechanism

 Next, the zinc compound solution supply mechanism 321 provided in the vaporization mechanism 320 will be described below. Each of the connecting pipes 340a to 340e is connected to a zinc compound solution supply mechanism 321 for supplying a zinc compound solution. The zinc compound solution supply mechanism 321 is connected to a zinc compound solution supplied to the orifice pipe 324. For the sake of convenience of explanation, only the zinc compound solution supply mechanism 321 provided in the connection pipe 340a will be described because only the types of physical solutions are different and the configuration is the same.

[0132] Incidentally, the connection pipes 340a to 340e are arranged in the orifice pipe 324 so that the openings do not face each other, so that, for example, the opening force of the connection pipe 340a is also supplied to the orifice pipe 324. The zinc compound solution is surely prevented from flowing into the openings of the other connecting pipes 340b to 340e.

In this case, in the zinc compound solution supply mechanism 321, the zinc compound mixture solution stored in the zinc compound mixture solution cylinder 350 as a solution cylinder is passed through a predetermined zinc compound solution flow path 351. By passing, the liquid mass flow controller (LMFC) 352 and the block valve 353 are sequentially supplied to the orifice pipe 324. The liquid mass flow controller 352 controls the flow rate of the zinc compound solution flowing through the zinc compound solution flow path 351! Speak.

[0134] The block valve 353 includes first to fourth switching valves 355a to 355d, and these first to fourth switching valves 355a to 355d are generally controlled by a control unit (not shown). .

[0135] In practice, when supplying zinc compound solution to orifice tube 324, block valve 353

Only the first switching valve 355a is opened and the other second to fourth switching valves 355b to 355d are closed.

 Thereby, in the orifice pipe 324, the zinc compound solution is supplied to the carrier gas flowing at high speed, and the zinc compound solution is made fine particles or mist by the carrier gas flowing at high speed. Thus, it can be dispersed in a carrier gas and supplied to the vaporizing section 425.

 [0137] In addition to the cover structure, in the zinc compound solution supply mechanism 321, the block valve 353 force also supplies the zinc compound solution to the orifice pipe 324. By supplying the solvent stored in the solvent cylinder 357 as a liquid via a predetermined solvent flow path 358, the liquid mass flow controller (LMFC) 359 and the connection pipe 340a are sequentially supplied to the orifice pipe 324. It is composed of

 [0138] In this case, the control unit closes the first switching valve 355a, the third switching valve 355c, and the fourth switching valve 355d, and opens only the second switching valve 355b. Thus, the solvent can be supplied to the orifice pipe 324 through the connection pipe 340a. In addition, the force of the connecting pipe 340a can be removed by flowing only the solvent through the orifice pipe 324 so that the solid matter clogged in the connecting pipe 340a can be removed!

[0139] In contrast, the control unit includes the first switching valve 355a, the second switching valve 355b, and the fourth switching valve. The switching valve 355d is closed and only the third switching valve 355c is opened, so that the solvent can be supplied to the vent pipe 361 via the block valve 353 and discarded.

 [0140] The control unit closes the first switching valve 355a, the second switching valve 355b, and the third switching valve 355c, and opens the fourth switching valve 355d. The zinc compound solution can be supplied to the vent pipe 361 via the block valve 353 and discarded.

 [0141] In the above configuration, in the CVD unit, the zinc compound solution is supplied to the carrier gas flow that always flows at high speed toward the reaction chamber 44 in the orifice tube 324, whereby the zinc compound solution is finely divided. The gas is vaporized in the vaporizing section 425 and supplied to the reaction chamber 44 as it is.

 [0142] In the vaporization mechanism 320, the zinc compound solution is instantaneously atomized by the high-speed carrier gas flow, and the zinc compound solution is easily vaporized by the heat of the heater 342. Thus, it is difficult to vaporize, and even the zincy compound solution obtained by dissolving the zincy compound in a solvent can be easily vaporized in the vaporizing section 325.

 Further, in the vaporization mechanism 320, the carrier gas pressurized in the carrier gas supply pipe 323 is introduced into the orifice pipe 324 at a high speed (for example, the carrier gas is 500 to 1000 Torr, 200 mlZmin to 2LZmin). Thus, the temperature rise of the zinc compound solution can be suppressed.

 [0144] Therefore, in this vaporization mechanism 320, only the solvent in the zinc compound solution can be prevented from evaporating in the orifice tube 324, so that the concentration of the zinc compound solution in the orifice tube 324 is increased. It is possible to prevent the zinc compound from precipitating as well as to suppress the increase in viscosity.

 [0145] Furthermore, in the vaporization mechanism 320, since the zinc-containing compound solution dispersed in the carrier gas can be instantly vaporized in the vaporizing section 325, the zinc-rich compound is present in the vicinity of the pores 335 and 335. Since only the solvent in the solution can be prevented from vaporizing, clogging of the pores 335 can be prevented. Thus, the continuous use time of the CVD vaporizer 2 can be extended.

(1 7) Example 7 In FIG. 18, reference numeral 390 denotes a roller type plasma CVD apparatus as an acid / zinc / zinc layer forming apparatus, which has a configuration in which a plurality of the above-described CVD vaporizers 2 are provided in the roller type CVD unit 391.

 In this roller type plasma CVD apparatus 390, a plurality of plasma generators 392a to 392e are provided in the roller type CVD unit 391, and the film-forming tape 393 is allowed to run in the forward direction F. By running in the direction R opposite to the forward direction F, each of the plasma generators 392a to 392e can form a zinc oxide epitaxy layer!

 [0147] In practice, this roller type plasma CVD apparatus 390 is provided with the CVD vaporizer 2 of the present invention for each of the plasma generators 392a to 392e, and has the same effect as the above-described Example 6. Obtainable.

 Incidentally, in this roller type plasma CVD apparatus 390, a first take-up roller 396 and a second take-up roller 397 are arranged in a reaction chamber 394 with a film forming roller 395 sandwiched therebetween. In addition, a first feed roller 398 and a first tension control port roller 399 are disposed on one side of the film formation roller 395, and a second feed roller 400 and a first tension control roller 399 are disposed on the other side of the film formation roller 395. A second tension control roller 401 is disposed. The film forming roller 395 has a large diameter of 300 to 20000 mm, for example, and a width of 2 m, for example.

 Accordingly, in the roller type plasma CVD apparatus 390, the first take-up roller 396 to the first feed roller 398, the first tension control roller 399, the film forming roller 395, the second tension control roller 401 and A travel path for traveling the film-forming tape 393 is formed on the second winding roller 387 via the second feed roller 400, and the film-forming tape 393 is moved along the travel path by the first winding roller 393. It can travel in the direction (forward direction F) from the take-up roller 396 to the second take-up roller 397, and the opposite direction R from the second take-up roller 397 to the first take-up roller 396. You can drive in the opposite direction.

[0150] In this case, each of the plasma generators 392a to 392e is provided corresponding to each area on the film forming roller 395, and a CVD gas is formed in a portion of the film forming tape 393 located on the area. The fixture 2 can be operated to form an oxide zinc epitaxy layer. In addition, each plasma generator 392a to 392e and CVD vaporizer 2 are controlled so that various CVD conditions can be set individually, so that the formed zinc oxide epitaxy layer can also be set individually. It is configured so that the film forming operation can be individually controlled or the film forming operation can be stopped individually.

 [0151] A partition plate 405 is disposed between the plasma generators 392a to 392e adjacent to each other in order to prevent interference of the zinc compound gas. 406 is an exhaust pipe, 407 is a deposition plate, 408 is a gas shower electrode, and 409 is an RF power source. In this embodiment, the film forming roller 395 is turned off, the gas shower electrode 408 is connected to the terminal of the RF power source 409, and the potentials of the plasma generators 392a to 392e are increased!

 [0152] In such a roller-type plasma CVD apparatus 390, the operation of causing the film-forming tape 393 to run in the forward direction F or in the reverse direction R is repeated alternately, for example, 50 layers to: LOOO The layer and the oxalic acid zinc epitaxy layer can be formed relatively efficiently.

 (1 8) Example 8

 In FIG. 19, in which parts corresponding to those in FIG. 18 are assigned the same reference numerals, 420 denotes a roller type plasma CVD apparatus as an acid / zinc layer forming apparatus, and this roller type plasma CVD apparatus 420 is described above. This is different from the embodiment 7 in that the film forming roller 395 has a higher potential. That is, the roller type plasma CVD apparatus 420 is different in that one end of one RF power source 421 is connected to the film forming roller 395 and the gas shower electrode 408 of each plasma generator 392a to 392e is grounded. Such a roller type plasma CVD apparatus 420 is also provided with the CVD vaporizer 2 of the present invention, so that the same effect as that of the above-described Example 6 can be obtained.

 (1 9) Example 9

 In FIG. 20, in which parts corresponding to those in FIG. 18 are assigned the same reference numerals, 430 indicates a roller type thermal CVD apparatus as an acid / zinc / zinc layer forming apparatus, and this roller type thermal CVD apparatus 430 generates plasma. The apparatus is not provided, and is different from the above-described embodiment 7 in that no voltage is applied between the gas shower plate portions 431a to 431e and the film forming roller 395. Incidentally, the roller-type thermal CVD apparatus 430 is configured so that the film-forming tape 393 can be heated mainly by the film-forming roller 395.

[0153] Even in the roller thermal CVD apparatus 430 that performs such a CVD film generation process, the CVD air heater 2 of the present invention is provided for each of the gas shower plate portions 431a to 431e. The same effects as in Example 6 described above can be obtained.

 [0154] As described above, according to Claim 4, the present invention forms a zinc oxide epitaxy layer (referred to as a "first oxide-zinc epitaxy layer" for convenience) on the surface of the substrate. After that, the substrate is heated to a higher temperature as appropriate, and further on the first oxide-zinc epitaxy layer, an acid-zinc epitaxy layer (for convenience, a “second acid-zinc epitaxy layer”) is formed. Therefore, the first oxide-zinc epitaxy layer is used as a buffer layer that adjusts the difference in lattice constant between the substrate and the second oxide-zinc epitaxy layer. 2 oxide / bell tin epitaxy layer can be obtained, and this second acid / zinc epitaxy layer can be used as a natural crystal (epitaxy) layer, which is a good quality product such as a blue light emitting diode. Can be obtained.

 [0155] Further, corresponding to claim 5, in the method for forming an zinc oxide epitaxy layer according to claim 4, before forming the zinc oxide epitaxy layer on the surface of the substrate, Since the surface of the plate is subjected to oxygen baking, the surface of the substrate can be made better. Therefore, the crystallinity of the first oxide / zinc epitaxy layer formed directly on the surface of the substrate is improved, and thus the second oxide / zinc epitaxy layer formed on the first oxide / zinc epitaxy layer is further crystallized. Can be made even better.

 [0156] Further, corresponding to claim 8, using the acid-zinc epitaxy layer forming apparatus of claim 6, the zinc-containing compound solution is vaporized by a vaporizer of the apparatus, and at least the zinc-containing compound is By supplying a gas obtained by vaporizing a solution of the substance onto the substrate heated to a certain temperature range on the substrate holding unit, the first zinc oxide epitaxy layer formed on the substrate and the substrate Since it was heated to a temperature in a range higher than the above range and formed into a laminated structure with the second oxide / zinc epitaxy layer formed on the first oxide / zinc epitaxy layer, it was directly applied to the surface of the substrate. It is possible to improve the crystallinity of the second acid-zinc epitaxy layer formed above the crystallinity of the first acid-zinc epitaxy layer to be formed. Making the original crystal layer with the epitaxy layer Can do. Therefore, a high-quality product such as a blue light emitting diode can be obtained.

[0157] Further, corresponding to claim 12, by supplying a gas obtained by vaporizing a zinc compound solution to the chamber, an acid zinc layer is formed on the substrate in the chamber. How to form a layer In the method, a carrier gas supply step for supplying a carrier gas to the chamber by flowing a carrier gas toward an inlet / outlet outlet of the carrier gas channel, and a zinc for supplying the zinc compound solution to the carrier gas channel. A compound solution supplying step, and the zinc compound solution is dispersed in the carrier gas in the form of fine particles or mist in the carrier gas flow path, and is supplied to the vaporization chamber provided at the outlet of the carrier gas flow path A vaporizing chamber supplying step, a vaporizing step in which the zinc compound solution is heated by the heating means of the vaporizing chamber in the vaporizing chamber, and a gas vaporized in the vaporizing step on the heated substrate. A first zinc oxide layer forming step for forming a zinc oxide layer; and heating the substrate to a higher temperature to form a first layer on the first oxide zinc layer. A second zinc oxide layer forming step for forming a second zinc oxide layer, wherein the first zinc oxide layer forming step includes heating the substrate to a temperature of 200 to 650 ° C. In the second acid / zinc layer forming step, the substrate is heated to a temperature of 400 to 1100 ° C. to form a second acid / zinc layer on the first acid / zinc layer. Since the first oxide / zinc layer is formed, the first oxide / zinc epitaxy layer is used as a notch layer that adjusts the difference in lattice constant between the substrate and the second oxide / zinc epitaxy layer. The second oxide-zinc epitaxy layer with extremely good properties can be obtained, and this second oxide-zinc epitaxy layer can be used as the original crystal (epitaxy) layer, which leads to a good quality product. For example, a blue light emitting diode or a piezo element can be obtained.

(2) Zinc oxide polycrystalline layer

 In the above-described embodiments, the thin film formed is described in the case of an oxide zinc epitaxy layer V. However, by using the same zinc oxide layer forming apparatus and changing the thin film formation conditions as appropriate, the oxide zinc oxide is used. A polycrystalline layer can be formed. The outline of the case of the zinc oxide polycrystalline layer will be described below.

(2-1) Example 10

This example corresponds to Example 1 described above, and the pressure inside the nozzle 6 is measured by the pressure gauge 12 while forming a polycrystalline zinc oxide zinc layer on the surface of the substrate 48 as an object to be formed as shown in FIG. To do. When the pressure exceeds the reference value, the thin film forming process is stopped and the nozzle 6 is tallyed. This makes it possible to form a stable zinc oxide polycrystalline layer on the substrate 48. (2-2) Example 11

 This embodiment corresponds to the second embodiment, and in the zinc oxide layer forming apparatus shown in FIG. 2, the RF application electrode 80 provided in the reaction chamber 44 is electrically grounded to the substrate stage 46 and A plasma is formed between them. As described above, the plasma CVD unit 4a forms plasma on the substrate 48. Therefore, the thin film formation process is performed at a lower temperature than that in the CVD unit 4 as shown in FIG. A layer can be formed on the substrate 48. (2-3) Example 12

 This embodiment corresponds to the above-described embodiment 3, and in the acid / zinc / zinc layer forming apparatus shown in FIG. Since the shower plate 100 is provided inside the reaction chamber 44 so that it can be easily formed, an oxide-zinc polycrystalline layer having a uniform film quality and thickness can be formed on the wafer-like substrate 48 having a large diameter. (2-4) Example 13

 This example corresponds to Example 4 above, and in the zinc oxide layer forming apparatus shown in FIG. 4, an RF voltage is applied between the shower plate 100 and the substrate stage 46 to generate plasma on the substrate 48. As a result, it is possible to form a zinc oxide polycrystalline layer having a uniform film quality and thickness on a large wafer-like substrate 48. Can form a zinc oxide polycrystalline layer at ~ 500 ° C

(2-5) Example 14

 This example corresponds to Example 5 above, and as shown in the method for forming the zinc oxide layer in FIG. 5A, for example, on the substrate 48 having a wafer-like sapphire force formed so that the A surface becomes the main surface. In the method of forming only one zinc oxide polycrystalline layer, for example, 400 to: L is formed by CVD under a high temperature of 100 ° C., and a thin film having a thickness of 2500 to 1000 A, for example, can be formed. I'll do it.

 [0158] Also, as shown in FIG. 5B, first, the first oxide zinc polycrystalline layer 200a is formed as a buffer layer, and the second oxide zinc polycrystalline layer 200b is formed thereon. It is good also as forming.

In addition, as shown in FIG. 5 (C), the first acid-zinc zinc polycrystal in the method shown in FIG. 5 (B) Before the formation of the layer 200a, the surface of the sapphire substrate 48 is subjected to oxygen baking at a temperature of, for example, 570 to L100 ° C., to obtain the oxide zinc polycrystalline layers 200a and 200b. (2-6) Example 15

 In the orifice pipe 324 shown in FIG. 17, by supplying the zinc compound solution to the carrier gas flow that always flows at a high speed toward the reaction chamber 44, the zinc compound solution is dispersed in the carrier gas in the form of fine particles or mist. Then, the gas is vaporized in the vaporization section 425 as it is, and this gas is supplied to the reaction chamber 44.

 [0160] By virtue of the vaporization mechanism 320, the zinc compound solution is instantaneously atomized by the high-speed carrier gas flow, and the zinc compound solution is easily vaporized by the heat of the heater 342. Thus, since it is difficult to vaporize, even the zincy compound solution obtained by dissolving the zincy compound in a solvent can be easily vaporized in the vaporizing section 325. Therefore, a thick (2500 to 1000 A) acid zinc zinc polycrystalline layer can be formed with good reproducibility.

 (2-7) Example 16

 In FIG. 18, reference numeral 390 denotes a roller type plasma CVD apparatus as an acid / zinc / zinc layer forming apparatus, which has a configuration in which a plurality of the above-described CVD vaporizers 2 are provided in the roller type CVD unit 391.

 [0161] In this roller type plasma CVD apparatus 390, a plurality of plasma generators 392a to 392e are provided in the roller type CVD unit 391, and the film forming tape 393 is moved in the forward direction F, or the By running in the direction R opposite to the forward direction F, a zinc oxide crystal layer can be formed in each of the plasma generators 392a to 392e!

 [0162] In practice, this roller type plasma CVD apparatus 390 is provided with the CVD vaporizer 2 of the present invention for each of the plasma generators 392a to 392e, and has the same effect as the above-described Example 15. Obtainable.

 (2-8) Example 17

In FIG. 19, in which parts corresponding to those in FIG. 18 are assigned the same reference numerals, 420 denotes a roller type plasma CVD apparatus as an acid / zinc layer forming apparatus, and this roller type plasma CVD apparatus 420 is described above. This is different from the embodiment 16 in that the potential of the film forming roller 395 is high. That is, in the roller type plasma CVD apparatus 420, one end of one RF power source 421 is connected. The difference is that the gas shower electrode 408 of each plasma generator 392a to 392e is connected to the film forming roller 395 and grounded. Even in such a roller type plasma CVD apparatus 420, since the CVD vaporizer 2 of the present invention is provided, it is possible to obtain the same effects as those of the embodiment 15 described above.

 (2-9) Example 18

 In FIG. 20, in which parts corresponding to those in FIG. 18 are assigned the same reference numerals, 130 indicates a roller thermal CVD apparatus as an acid / zinc / zinc layer forming apparatus, and this roller CVD apparatus 430 has a plasma generating apparatus. It is not provided and differs from the above-described embodiment 16 in that no voltage is applied between the gas shower plate portions 431a to 431e and the film forming roller 95. Even in such a roller-type thermal CVD apparatus 430, the vaporizer for CVD 2 of the present invention is provided for each of the gas shower plate portions 431a to 431e, so that the same effect as that of the above-described Example 15 can be obtained. It is out.

 The present invention is not limited to this embodiment, and various modifications can be made within the scope of the gist of the present invention. For example, the solution cylinder and the cleaning liquid cylinder may be a solution tank or a cleaning liquid tank.

 [0164] Further, although the acid-zinc layer has been described with respect to an acid-zinc epitaxy layer and an acid-zinc polycrystalline layer, the present invention is not limited to this, and the thin-film formation conditions can be changed as appropriate. As a formation of an amorphous layer.

 [0165] As described above, the present invention corresponds to claim 11, wherein the zinc compound solution is vaporized by a vaporizer, and the gas vaporized from the zinc compound solution is heated to a certain temperature range on the substrate holder. A first zinc oxide layer formed on the substrate, and heating the substrate to a temperature in a range higher than the range to form the first zinc oxide layer on the first substrate. And the second zinc oxide layer formed on the surface of the substrate rather than the crystallinity of the first acid zinc layer formed directly on the surface of the substrate. The crystallinity of the layer can be improved.

[0166] The present invention is not limited to this embodiment, and various modifications can be made within the scope of the present invention. For example, the solution cylinder and the zinc compound mixture as the solution cylinder may be a solution tank or a zinc compound mixture tank. Also cleaning The solvent cylinder as the liquid cylinder and the cleaning solution cylinder may be a cleaning liquid tank or a solvent tank.

 INDUSTRIAL APPLICABILITY The present invention is generally applicable to a method for forming a zinc oxide layer, an apparatus for forming an acid / zinc layer used in the method, and an acid / zinc layer formed using the apparatus.

Claims

The scope of the claims

 [1] Vaporize the zinc compound solution with a vaporizer,

 An oxide zinc layer is grown on the substrate by supplying a gas obtained by vaporizing at least the zinc compound solution onto the substrate.

 A method for forming a zinc oxide layer.

 [2] An oxidizing gas is supplied to the vaporizer, and a zinc oxide layer is grown on the substrate by vaporizing the zinc compound solution supplied on the substrate and the oxidizing gas. The method for forming a zinc oxide layer according to claim 1.

[3] A zinc oxide layer is grown on the substrate by supplying an oxidizing gas onto the substrate to which the vaporized zinc compound solution is supplied.

 The method for forming a zinc oxide layer according to claim 1, wherein:

[4] The substrate is heated to a temperature within a certain range to form a zinc oxide layer on the surface, and then the substrate is heated to a temperature higher than the range above the zinc oxide layer. Further, a zinc oxide layer is formed

 The method for forming a zinc oxide layer according to claim 1, 2 or 3.

[5] Before forming the zinc oxide layer on the surface of the substrate, subject the surface of the substrate to oxygen baking.

 The method for forming a zinc oxide layer according to claim 4, wherein:

[6] At least a zinc compound solution and a carrier gas are received through a valve, and the tip of a nozzle that ejects the received substance from the tip is protruded into a vaporization chamber having an inner diameter that is significantly wider than the inner diameter of the nozzle, A vaporizer for receiving and evaporating fine particles or mist-like substances ejected from the nozzle tip force in the vaporization chamber;

 A CVD unit that has a substrate holding unit for holding the substrate inside the chamber, receives at least a gas supply from the vaporizer, and causes the oxide-zinc layer to grow on the substrate on the substrate holding unit;

 A device for forming a zinc oxide layer, comprising:

[7] At least a zinc compound solution and a carrier gas are received through a valve, and the tip of a nozzle that ejects the received substance from the tip has an inner diameter that is significantly wider than the inner diameter of the nozzle. A vaporizer that protrudes into the vaporization chamber and receives the vaporized fine particle or mist substance ejected from the nozzle tip force in the vaporization chamber, and has a substrate holding portion for holding the substrate inside the chamber, and at least A zinc compound solution is formed using a zinc oxide layer forming apparatus that includes a CVD unit that receives the supply of the gas having the vaporizer power and performs CVD growth of a zinc oxide layer on the substrate on the substrate holding unit. Formed on the substrate by supplying a gas obtained by vaporizing at least the zinc compound solution to the substrate on the substrate holding unit.

 A zinc oxide layer characterized by that.

[8] At least a zinc compound solution and a carrier gas are received through a valve, and the tip of a nozzle that ejects the received substance from the tip is protruded into a vaporization chamber having an inner diameter that is significantly larger than the inner diameter of the nozzle, This nozzle tip force has a vaporizer that receives the vaporized particulate or mist-like substance in its vaporization chamber and vaporizes it, and a substrate holding portion that holds the substrate inside the chamber, and at least the gas having the vaporizer power The zinc compound solution is vaporized by the vaporizer using a zinc oxide layer forming apparatus that includes a CVD unit that receives the supply of the chemical vapor and grows a zinc oxide layer on the substrate holding unit by CVD. Supplying a gas obtained by vaporizing at least a solution of the zinc compound onto the substrate heated to a temperature within a certain range on the substrate holding unit, thereby forming a first zinc oxide formed on the substrate. Layers,

 A second zinc oxide layer formed on the first zinc oxide layer by heating the substrate to a temperature in a range higher than the range;

 A zinc oxide layer having a laminated structure comprising:

[9] In an acid / zinc layer forming apparatus including a vaporizer that supplies a gas obtained by vaporizing a zinc compound solution to a chamber,

 The vaporizer is

 A carrier gas flow path through which the carrier gas flows from the inlet to the outlet;

 A zinc compound solution flow path for supplying the zinc compound solution to the carrier gas flow path; and a vaporization of the zinc compound solution supplied from the zinc compound solution flow path provided at an outlet of the carrier gas flow path With a vaporization chamber,

The carrier gas flow path is A carrier gas pipe to which the carrier gas is supplied;

 The carrier gas is supplied from the carrier gas pipe, and the zinc compound solution is dispersed in a carrier gas in the form of fine particles or mist and supplied to the vaporization chamber. The vaporization chamber includes the carrier Equipped with heating means to heat and vaporize the zinc compound solution dispersed in the gas

 A device for forming a zinc oxide layer.

 [10] In the method of forming an acid zinc layer on the substrate in the chamber by supplying a gas obtained by vaporizing the zinc compound solution to the chamber,

 A carrier gas supply step of supplying the carrier gas to the chamber by flowing the carrier gas toward the inlet loca outlet of the carrier gas channel;

 A zinc compound solution supply step for supplying the zinc compound solution to the carrier gas channel;

 A vaporization chamber supply step of dispersing the zinc compound solution in a carrier gas flow path in the form of fine particles or mist and supplying the zinc compound solution to a vaporization chamber provided at an outlet of the carrier gas flow path; ,

 A vaporizing step in which the zinc compound solution is heated by the heating means of the vaporizing chamber and vaporized in the vaporizing chamber.

 A method for forming a zinc oxide layer.

 [11] In the method for forming an acid / zinc layer, wherein a gas obtained by vaporizing the zinc / compound solution is supplied to the chamber to form an acid / zinc layer on the substrate in the chamber.

 A carrier gas supply step of supplying the carrier gas to the chamber by flowing the carrier gas toward the inlet loca outlet of the carrier gas channel;

 A zinc compound solution supply step for supplying the zinc compound solution to the carrier gas channel;

A vaporization chamber supply step of dispersing the zinc compound solution in a carrier gas flow path in the form of fine particles or mist and supplying the zinc compound solution to a vaporization chamber provided at an outlet of the carrier gas flow path; , A vaporizing step in which the zinc compound solution is heated and vaporized by heating means of the vaporizing chamber in the vaporizing chamber;

 A first zinc oxide layer forming step of forming a first zinc oxide layer on the heated substrate by the gas vaporized in the vaporization step;

 A second zinc oxide layer forming step of heating the substrate to a higher temperature to form a second acid zinc layer on the first acid zinc layer.

 A method for forming a zinc oxide layer.

 In the first zinc oxide layer forming step, the substrate is heated to a temperature of 200 to 650 ° C. to form a first zinc oxide layer,

 In the second oxide / zinc layer forming step, the substrate is heated to a temperature of 400 to 1100 ° C. to form a second oxide / zinc layer on the first oxide / zinc layer. The method for forming a zinc oxide layer according to claim 11.