JP2011040771A - Material gas decomposing mechanism, thin film manufacturing device, thin film manufacturing method, and thin film laminate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a material gas decomposing mechanism that facilitates depositing a thin film of high quality on a substrate. <P>SOLUTION: The material gas decomposing mechanism provided for a thin film manufacturing device 1 that achieves vapor-phase deposition of a thin film on a substrate 21 in a pressure-reduced chamber 17, and decomposing decomposition species of one or a plurality of kinds of material gases being a material of the thin film to generate decomposition species of the material gases is provided with one or a plurality of gas introduction pipes 13 each having an opening communicating with a reaction room and configured to introduce the material gas into the reaction room through the opening, a catalyst 10 for material gas decomposition in proximity to the opening while displaced toward the substrate more than an opening surface of the opening on the side of the reaction room, and a heating power supply 12 for raising a temperature of the catalyst 10 by turning on electricity to the catalyst 10 through wires 11a, 11b. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a raw material gas decomposition mechanism, a thin film forming apparatus, a thin film manufacturing method, and a thin film laminate.

  According to the present invention, it is possible to obtain a nitride semiconductor thin film that is superior in light emission efficiency and dielectric breakdown electric field strength as compared with the prior art. In addition, a dense protective film can be formed on a substrate that is vulnerable to thermal damage such as an organic film.

  Conventionally, a nitride thin film formed by combining a nitrogen raw material and a metal raw material has not only excellent performance as an optical device or electronic device, but also an insulator, when it has physical properties as a semiconductor. When it has the physical properties, it exhibits excellent performance as an insulating protective film. For this reason, nitride thin films are attracting attention in a wide variety of fields.

  When forming this nitride thin film, generally a method of vapor-depositing a nitrogen source gas and a metal source on a substrate is employed. In this vapor deposition method, thermal CVD (Thermal Chemical Vapor Deposition), metal organic chemical vapor deposition (MOCVD), plasma enhanced CVD (PECVD), molecular beam epitaxial growth (MBE: Molecular Beam Epitaxy) and catalytic CVD (Catalytic Chemical Vapor Deposition) are known.

  The thermal CVD method and the MOCVD method have a problem that the substrate is heated to a high temperature, and thus the substrate is thermally damaged. The PECVD method has a problem that plasma in the gas phase causes the plasma damage to the substrate. For this reason, a catalytic CVD method that can form a nitride thin film without heating the substrate to a high temperature and without a plasma has attracted attention. This catalytic CVD is a method in which a source gas is brought into contact with a heated catalyst body for catalytic decomposition and a nitride thin film is formed on the substrate. In addition to the nitride thin film, a polycrystalline silicon thin film or an amorphous silicon thin film is deposited. Are also known to be useful (see Patent Documents 1 and 2).

JP-A 61-276976 JP-A-8-250438

  By the way, in the catalytic CVD method, it is necessary to bring the catalyst body and the substrate close to each other in order to cause the decomposed species of the source gas decomposed by the catalyst body to reach the substrate by heating the catalyst body to a high temperature. However, if the distance between the catalyst body and the substrate is too close, there is a problem that the substrate becomes high temperature due to the radiant heat of the catalyst body and a high-quality film is not formed.

  The present invention has been made in view of the above, and is a raw material gas decomposition mechanism, a thin film manufacturing apparatus, a thin film manufacturing method, and a high quality thin film laminate that facilitates the deposition of a high quality thin film on a substrate. The purpose is to provide.

  Even if the raw material gas decomposition mechanism, thin film manufacturing apparatus, and thin film manufacturing method of the present invention are applied to thin films other than nitride thin films, the merit of low temperature deposition can be obtained.

  In order to achieve the above object, the raw material gas decomposition mechanism according to the present invention is provided in a thin film manufacturing apparatus for vapor-depositing a thin film on a substrate in a reaction chamber under reduced pressure, and one or a plurality of raw materials for the thin film are used. A raw material gas decomposition mechanism for decomposing various kinds of raw material gases to generate decomposition species of the raw material gas, comprising an opening communicated with the reaction chamber, and the raw material in the reaction chamber through the opening One or a plurality of source gas introduction means for introducing a gas, and a source material arranged in a state of being displaced closer to the substrate side than an opening surface on the reaction chamber side in the opening portion and in a state of being close to the opening portion It comprises a catalyst body for gas decomposition and a catalyst body heating means for raising the temperature of the catalyst body by energizing the catalyst body.

  In the thin film manufacturing apparatus according to the present invention, when vapor-depositing a thin film on a substrate in a reaction chamber under reduced pressure, one or more kinds of raw material gases as raw materials for the thin film are decomposed by a raw material gas decomposition mechanism, and A thin film manufacturing apparatus for generating a decomposition species of a source gas, wherein the source gas decomposition mechanism has an opening communicating with the reaction chamber, and introduces the source gas into the reaction chamber through the opening One or a plurality of source gas introduction means for performing the source gas decomposition disposed in a state of being displaced closer to the substrate side than the opening surface on the reaction chamber side in the opening portion and in a state of being close to the opening portion And a catalyst body heating means for raising the temperature of the catalyst body by energizing the catalyst body.

  A thin film manufacturing method according to the present invention is a thin film manufacturing method in which a thin film is vapor-deposited on a substrate in a reaction chamber under reduced pressure, and one or more kinds of source gases serving as a raw material of the thin film are used in the present invention. The method includes a step of generating a decomposition species of the raw material gas by decomposing by a raw material gas decomposition mechanism.

  The thin film laminate according to the present invention has a plurality of thin films laminated on a substrate, and the plurality of thin films include at least one thin film produced by the thin film production method of the present invention. .

  In the raw material gas decomposition mechanism according to the present invention, the catalyst body is disposed in a state of being displaced closer to the substrate side than the opening surface at the opening portion on the reaction chamber side in the raw material gas introducing means and in the state of being close to the opening portion. Therefore, compared with the case where the catalyst body is arranged inside the raw material gas introduction unit with respect to the opening surface, collision between the decomposition species is suppressed. For this reason, it is easy to irradiate the substrate with a desired decomposition species. As a result, it becomes easy to deposit a high-quality thin film on the substrate.

It is a block diagram which shows the thin film manufacturing apparatus concerning Embodiment 1 of this invention. It is a characteristic view which shows the characteristic of the electrical resistance and temperature of the tungsten wire concerning Embodiment 1 of this invention. It is a characteristic view which shows the characteristic of the temperature and pressure of the tungsten wire concerning Embodiment 1 of this invention. It is a schematic diagram which shows the shutter concerning Embodiment 1 of this invention. It is a schematic diagram which shows the shutter concerning Embodiment 1 of this invention. It is a schematic diagram which shows the gas introduction pipe | tube concerning Embodiment 1 of this invention. It is a schematic diagram which shows the catalyst body shape concerning Embodiment 1 of this invention. It is a schematic diagram which shows the catalyst body shape concerning Embodiment 1 of this invention. It is a schematic diagram which shows the catalyst body shape concerning Embodiment 1 of this invention. It is a schematic diagram which shows the catalyst body shape concerning Embodiment 1 of this invention. It is a schematic diagram which shows the catalyst body shape concerning Embodiment 1 of this invention. It is a schematic diagram which shows the catalyst body shape concerning Embodiment 1 of this invention. It is a schematic diagram which shows the catalyst body shape concerning Embodiment 1 of this invention. It is a schematic diagram which shows the catalyst body shape concerning Embodiment 1 of this invention. It is a schematic diagram which shows the catalyst body shape concerning Embodiment 1 of this invention. It is a schematic diagram which shows the catalyst body shape concerning Embodiment 1 of this invention. It is a block diagram which shows the nitride thin film manufacturing apparatus concerning the modification of Embodiment 1 of this invention. It is a block diagram which shows the thin film manufacturing apparatus concerning Embodiment 2 of this invention. It is a block diagram which shows the thin film manufacturing apparatus concerning Embodiment 3 of this invention. It is a block diagram which shows the thin film manufacturing apparatus concerning Embodiment 4 of this invention. It is a block diagram which shows the thin film manufacturing apparatus concerning Embodiment 5 of this invention. It is a schematic diagram which shows the RHEED pattern concerning embodiment of this invention. It is a schematic diagram which shows the RHEED pattern concerning embodiment of this invention. It is a characteristic view which shows the XRD pattern concerning embodiment of this invention. It is a schematic diagram which shows PL pattern concerning embodiment of this invention. It is a cross-sectional schematic diagram which shows the lamination | stacking cross section by which the thin film concerning embodiment of this invention was laminated | stacked. It is a schematic diagram which shows the dent of the thin film concerning embodiment of this invention. It is process drawing which shows the process of thin film formation concerning embodiment of this invention. It is process drawing which shows the process of thin film formation concerning embodiment of this invention. It is a characteristic view which shows the XRD pattern concerning embodiment of this invention. It is a schematic diagram which shows PL pattern concerning embodiment of this invention.

  Exemplary embodiments of a thin film manufacturing apparatus, a thin film manufacturing method, and a thin film stack according to the present invention will be described below in detail with reference to the accompanying drawings.

(Embodiment 1)
FIG. 1 is a block diagram showing a schematic configuration of a nitride thin film manufacturing apparatus 1 according to Embodiment 1 of the present invention. The nitride thin film manufacturing apparatus 1 includes a chamber 17 that is a reaction chamber for forming a nitride thin film, a vacuum pump 18 that depressurizes the chamber 17 to a predetermined pressure, and ammonia (NH ₃ ) that is a nitrogen source gas in the chamber 17. Is introduced into the gas inlet tube 13, the catalyst body 10 is disposed at the opening of the gas inlet tube 13 and dissociates the introduced NH ₃ , and gallium (Ga), which is a metal raw material, is heated and released as a molecular beam. A Knudsen cell 22a, a Si substrate 21 for forming gallium nitride (GaN), a substrate holder 19 for holding the Si substrate 21, a heater 20 for heating the Si substrate 21, and a refrigerant supply pipe 81 for cooling the Si substrate 21 are provided. Have. A shroud 82 that adsorbs undecomposed source gas is provided around the Si substrate 21. A reflection high-energy electron diffraction (RHEED) 24 and screen 25 for observing the state of the Si substrate 21 and the deposited film, and a quadrupole mass spectrometer (QMS) 23 for detecting residual gas in the chamber 17 are included. .

  The Si substrate 21 is attached to a substrate holder made of molybdenum or the like, and a substrate holder inside the chamber 17 is not opened to the atmosphere by a load lock system (not shown in FIG. 1) without opening the chamber 17 to the atmosphere. 19 is transported in vacuum and attached. The Si substrate 21 can be adjusted to an arbitrary temperature by the heater 20 and the refrigerant supply pipe 81 provided in the substrate holder 19. The monitoring of the substrate temperature is achieved by using a thermocouple (not shown) provided in the substrate holder 19 or observing thermal radiation from the substrate with a pyrometer (not shown). When a wide gap material such as a gallium nitride substrate is used as the substrate, it is necessary to deposit a refractory metal in advance on the back surface of the substrate.

The exhaust device is preferably a turbo molecular pump, and an oil diffusion pump equipped with a cryopump or a liquid nitrogen trap can also be used. Further, an ion pump or a titanium sublimation pump can be used to improve the degree of vacuum before flowing the source gas. With such an exhaust device, the ultimate vacuum when the source gas is not introduced is generally about 1 × 10 ⁻¹⁰ Torr. Further, although not shown here, the exhaust device includes a detoxification facility corresponding to the source gas.

  Ammonia, which is a nitrogen source gas, is adjusted to an appropriate pressure by a pressure control device from a cylinder 16 stored in a cylinder cabinet, and adjusted to a desired flow rate through valves 14a and 14b and a flow rate controller (MFC) 15. It is adjusted and finally introduced into the chamber 17 through the gas introduction pipe 13. In addition to this, although not shown here, it is necessary to provide the source gas supply system with purge means and various safety devices for measures against leakage.

Although the case of using ammonia (NH ₃ ) as the nitriding source gas will be described, a nitrogen hydride source such as hydrazine (N ₂ H ₄ ) or hydrogen azide (N ₃ H) can be used. In addition, hydrogen can be mixed with these nitrogen source gases, or an inert gas such as nitrogen or a rare gas can be mixed. The selection of the source gas and the mixing of hydrogen are appropriately selected to adjust the ratio of nitrogen / hydrogen as a component of the source gas supplied to the heating catalyst body 10. On the other hand, the mixing of nitrogen and rare gas has an effect of suppressing the reaction of the nitrogen source gas in the heating catalyst body 10.

  In the case of using a mixed gas, this can be achieved by branching the source gas introduction pipe 13 on the supply side and providing means for supplying these gases. It is also effective to adjust the gas mixing state in the gas introduction pipe 13 by providing an exhaust means in the source gas introduction pipe.

  A catalyst body 10 is provided at an opening at the tip of the gas introduction pipe 13, and the nitrogen source gas efficiently contacts the catalyst body 10.

  The catalyst body 10 is connected to a heating power source 12 through conductive wires 11a and 11b formed of silver-coated copper (Cu), and is set to a desired temperature by energization. The catalyst body 10 is formed in a W shape by a tungsten (W) wire having a purity of 99.999%, and is arranged in parallel to the opening surface of the opening of the gas introduction pipe 13.

FIG. 2 shows the result of examining the electrical resistance characteristics of the tungsten wire by energization heating to the catalyst body 10. When a high-purity tungsten wire is used, the temperature of the tungsten wire can be estimated from the electrical resistivity of the tungsten wire. When the diameter of the tungsten wire is σ (mm) and the length is L (cm), the electrical resistivity ρ of the tungsten wire is given if the current flowing to the tungsten wire is I (A) and the voltage is V (V). (ΜΩm) is
ρ = V / I × σ / L × 10 ²
Can be obtained. If ρ exceeds 1 μΩm, the melting point of the tungsten wire is close to 3400 ° C., so the tungsten wire is broken. When ρ is 0.7 μΩm or more, the temperature of the tungsten wire becomes about 2000 ° C. or more, the vapor pressure of tungsten becomes high, and the evaporation becomes remarkable, so that the tungsten wire gradually becomes thinner and easily cut. It is not preferable because the wire evaporation adheres to the substrate and becomes an impurity. Moreover, when the tungsten purity of the tungsten wire is low, the reproducibility of the resistance-temperature relationship may change, and impurities may be mixed into the substrate. Accordingly, the tungsten purity of the wire is preferably 99.99% (4N) or higher, and desirably 99.999% (5N) or higher. At present, it is not easy to obtain tungsten of higher purity from the market, but there is a possibility that 6N purity can be easily used in the future.

  On the other hand, the decomposition of the source gas is accelerated as the temperature of the tungsten wire is increased. Therefore, when it is desired to promote the decomposition of the source gas, the temperature of the tungsten wire corresponding to 0.55 μΩm is preferably set to 1700 ° C. . The set temperature of the tungsten wire lower than this including no energization is selected and used according to the selection of the source gas and the purpose of the process because the constituent ratio of the decomposition species of the source gas changes.

The catalyst body 10 is disposed so as to face the Si substrate 21, and the nitrogen material decomposed by the catalyst body 10 is efficiently irradiated onto the substrate. Since a part of the nitrogen source gas introduced into the chamber 17 without being decomposed is adsorbed by the liquid nitrogen shroud 82 provided on the inner wall of the chamber 17, the nitrogen source gas of about 100 sccm is introduced as the pressure in the chamber 17. However, it can be set to 1 × 10 ⁻⁵ Torr or less.

  FIG. 3 shows the relationship between the tungsten filament temperature and the chamber 17 pressure when ammonia is flowed at 10 sccm. Here, the opening diameter of the gas introduction pipe 13 is 20 mm, and the distance between the catalyst body 10 and the Si substrate 21 is 10 cm.

  Ammonia gas introduced undecomposed is adsorbed by the shroud 82 and therefore does not increase the pressure in the chamber 17. When decomposition progresses in the catalytic reaction with the catalyst body 10, many components eventually change into hydrogen and nitrogen gas, and these are hardly adsorbed by the shroud 82. Is exhausted. Therefore, the chamber pressure shown in FIG. 3 serves as an index indicating the degree of decomposition of the ammonia gas by the heated catalyst body 10. In addition, the behavior of these raw material gas decomposition | disassembly can be investigated in detail with QMS23 attached to the apparatus.

When the ammonia gas as shown in FIG. 3 is 10 sccm, the chamber pressure is maintained at a low level of 1 × 10 ⁻⁵ Torr or less even when the tungsten filament is set at 1700 ° C. The chamber pressure and the ammonia gas flow rate are substantially proportional in this region, and even when the flow rate is 100 sccm or more, it is 1 × 10 ⁻⁴ Torr or less. This low chamber pressure is an effect of the shroud 82. If the shroud 82 is not cooled, the chamber pressure will exceed 1 × 10 ⁻³ Torr even if the ammonia gas is 10 sccm.

This chamber pressure value is an important parameter that affects the degree of arrival of the metal molecular beam from the source gas decomposition species to the substrate or the metal source supply means to the substrate. In general, in the region of low-pressure molecular flow, the mean free path λc (cm) of gas gas molecules is obtained by setting the pressure of gas gas molecules as Pc (Torr) (that is, a value corresponding to the chamber pressure).
λc = (5 × 10 ⁻³ ) / Pc
It is known that this relationship is almost satisfied.

First, the opening position of the Knudsen cell for supplying the metal raw material is generally arranged at a distance of 5 cm or more from the substrate. For the same reason, λc is 5 cm or more, and therefore Pc <1 × 10. ^-3 Torr must be satisfied. If λc is 5 cm or less, the metal molecular beam may collide with the gas before reaching the substrate and the reaction may be inhibited.

On the other hand, the heating catalyst body is arranged substantially coincident with the supply port of the raw material gas molecules, and is always kept under a gas molecule pressure higher than the pressure in the chamber 17. Using the flow rate J (sccm) of the source gas, the gas gas molecular velocity v (cm / s), and the opening area S (cm ² ) of the supply pipe, the pressure in the vicinity of the heated catalyst body, Pcat (Torr),
Pcat = 12.67 J / S / v
Can be estimated. When the gas molecular velocity at room temperature is 4.7 × 10 ⁴ cm / s and the opening diameter is 2 cm,
Pcat = 8.6 × 10 ⁻⁵ JTorr
It becomes the relationship.

When J is 100 sccm, Pcat reaches 8.6 × 10 ⁻³ Torr, and the corresponding mean free path is 0.58 cm. Although this value is small, gas spreads in the region between the substrate and the mean free path increases in the process from the catalyst body 10 to the substrate, so if L = 10 cm or less, It is possible to effectively irradiate the substrate with the dissociation source gas molecular beam from the catalyst body 10. As L is reduced, the contribution of collision with other gas molecules in the space before reaching the substrate can be reduced.

On the other hand, when L (cm) is reduced, the heat radiation from the heating catalyst body 10 increases the substrate temperature. The rise in the substrate temperature can be tolerated to some extent by using the means 81 for cooling the substrate temperature. However, since the influence of radiation becomes prominent in proportion to the square of the substrate distance, at least L is set to 1 cm or more. There is a need. Therefore, in the nitrogen source gas supply means of the present invention, the distance Lcm between the catalyst body 10 and the substrate is arranged so as to satisfy 1 ≦ L ≦ 10. In addition, the reaction chamber pressure at the time of introducing the raw material gas for thin film deposition is set to 1 × 10 ⁻³ Torr or less.

  In order to optimize the parameter L, it is important to set the raw material gas pressure in the heating catalyst body. To control this, it is effective to change the opening area of the gas introduction pipe 13. . As shown in FIG. 4, the aperture area changing means may be formed by a plurality of metal pieces in the shape of a diaphragm provided in the camera, or as shown in FIG. The shape may be such that the area can be varied.

  In the first embodiment, the gas introduction pipe 13 is fixed to the chamber 17. However, as shown in FIG. 6, the gas introduction pipe 13 is fixed to the chamber 17 via the bellows flange 88 and the gas introduction pipe 13 is introduced at the tip. The catalyst body 10 attached to the portion 83 may be driven by the handle 87 so that the screw 86 can be varied along the guide 85 so that the distance from the Si substrate 21 can be varied. Thereby, L itself can be adjusted to some extent, and the optimum deposition condition can be easily set. Moreover, it can be automated by using a motor instead of the handle 87.

  Here, although the wire which used tungsten as the raw material was demonstrated as the catalyst body 10, the catalyst body of forms other than another raw material and a wire can be utilized.

  Catalyst material that can be used as a wire includes tria-containing tungsten that is generally used as a filament material in addition to tungsten alone. In addition, other refractory metals such as molybdenum, tantalum, titanium, vanadium, osmium, high-purity iron, and platinum can be used. When using these materials, it is necessary to set energization conditions in view of the vapor pressure and resistivity of each material.

  Further, by combining with a tungsten filament or other heaters, it is possible to use various plate-like or tubular catalyst bodies without electrical conductivity. In this case, in addition to the above refractory metal material, the material is boron nitride, silicon nitride, ceramic materials such as aluminum nitride and silicon carbide, semiconductor materials such as silicon and gallium nitride, and ceramics thereof. Alternatively, the metal may be a metal-deposited ceramic, a refractory metal coated with a nitride film, silicide, or the like in which a metal is combined with a semiconductor.

  As a selection of these materials, a component that does not contain oxygen is preferable. When oxygen is included, the heating temperature of the catalyst body is set to the decomposition temperature or lower, and oxygen is mixed into the thin film unless it is sufficiently baked out. The same applies to carbon. In general, metals other than the thin film constituent elements adversely affect the properties of the thin film as impurities. Therefore, the metal added to the catalyst body is an element element constituting the thin film, such as Al, In, Ga, and B (nonmetal). However, a nitride ceramic composite of a raw material such as Si, Mg, or Fe that is useful as a raw material or a dopant such as those defined here together can be used as a good heating catalyst.

  In the case of a wire rod, the shape of the catalyst body 10 is a coil shape as shown in FIG. 7, a wire shape such as a W shape as shown in FIG. 8, and a spring shape as shown in FIG. May be. Also, these materials can be molded into a plate shape and heated by energization. As shown in FIG. 10, it can be a sheet shape, a ring shape as shown in FIG. 11, and a net shape as shown in FIG. On the other hand, these electrically heated catalyst bodies can be combined with another catalyst body heated by this heat. The form shown in FIG. 13 is a combination of a spring-like catalyst body that is energized and heated and a mesh-like catalyst body that is not energized. Further, as shown in FIG. 14, a shape in which a spring and a slit are combined, as shown in FIG. 15, a shape in which a conductor coil is combined with a donut-shaped insulator catalyst body, and as shown in FIG. Moreover, the shape which combined the donut-shaped coil with the slit may be sufficient.

(Modification 1 of Embodiment 1)
Next, Modification 1 of Embodiment 1 will be described. In the first embodiment, the nitride thin film manufacturing apparatus 1 forms GaN on the Si substrate 21 using one gas introduction tube 13 with the catalyst body 10 and one Knudsen cell 22a loaded with one Ga. However, in this modification, a Knudsen cell charged with indium (In) is further provided, and InGaN is formed on the GaAs substrate 21b instead of the Si substrate.

  FIG. 17 is a block diagram showing a schematic configuration of a nitride thin film manufacturing apparatus 1A which is this modification. This nitride thin film manufacturing apparatus 1A includes a Knudsen cell 22b in which In is loaded in a chamber 17 by replacing the Si substrate 21 shown in the first embodiment with a GaAs substrate 21A. In addition, the same code | symbol is attached | subjected to the component same as FIG.

(Modification 2 of Embodiment 1)
As another modification of the first embodiment, there is a configuration including a Knudsen cell 22c loaded with Al in addition to the Knudsen cell 22b loaded with In. Further, a Knudsen cell 22d loaded with Si used for n-type doping is provided, and a gas introduction pipe for supplying dimethylmagnesium (DMM) as an Mg raw material used for p-type doping is arranged. ing. The substrate 21 is used to sequentially form an n-type GaN layer, an undoped InGaN layer, and a p-type GaN layer after growing an AlN buffer layer using an n-type Si substrate having a plane orientation (111).

(Embodiment 2)
Next, a second embodiment of the present invention will be described. In the first embodiment and the modification thereof, the Knudsen cells 22a, 22b, 22c, 22d, and the gas introduction pipe 13a with the catalyst body 10 are arranged on the same plane as the gas introduction pipe 13b for p-type doping. However, in the second embodiment, the gas introduction pipe 13a with the catalyst body 10 is arranged so as not to interfere with the molecular beam of the Knudsen cell.

  FIG. 18 is a block diagram showing a schematic configuration of a nitride thin film manufacturing apparatus 2 according to Embodiment 2 of the present invention. As shown in FIG. 18, in this nitride thin film manufacturing apparatus 2, the gas introduction tube 13a with the catalyst body 10 is arranged on a surface perpendicular to the surface on which the Knudsen cells 22a to 22c look at the substrate 21B.

As described in Embodiment 1 shown in FIG. 1, when NH ₃ decomposition species reach the substrate 21B, the distance L between the substrate 21B and the catalyst body 10 is generally 1 cm to 10 cm. On the other hand, the distance between the tips of the Knudsen cells 22a to 22c and the substrate 21B is 20 to 30 cm.

  Therefore, for example, when four types of compound films are formed on the substrate 21B, three Knudsen cells 22a to 22c, one Knudsen cell for doping, and one gas cell for doping are added to the catalyst body 10. It is necessary to arrange one gas introduction pipe 13 in the chamber 17, but if the Knudsen cells 22a to 22c and the gas introduction pipe 13 with the catalyst body 10 are arranged in the same plane, the tip of the gas introduction pipe 13 with the catalyst body 10 is disposed. Interferes with the molecular beam emitted from the Knudsen cells 22a to 22c, and a good film is not formed on the substrate 21B.

  Therefore, disposing the Knudsen cells 22a to 22c without interfering with the molecular beam emitted from the Knudsen cells 22a to 22c by disposing the gas introduction tube 13 with the catalyst body 10 on a surface perpendicular to the surface on which the substrate 21B is viewed. The seed can reach the substrate 21B.

  In the second embodiment, the gas introduction tube 13a with the catalyst body 10 is disposed so as not to interfere with the molecular beam emitted from the Knudsen cells 22a to 22c, and a good film is formed on the substrate 21B.

  With this configuration, it is possible to arrange up to about 10 Knudsen cells corresponding to other thin film constituent elements, doping and surfactant-added elements. A plurality of gas supply pipes can also be provided. The catalyst body can be arranged in the gas supply pipe as in the case of 13a. In this case, it is preferable to arrange the catalyst body at a position where it does not interfere with other Knudsen cells like the gas introduction pipe 13a. A gas cell having no catalyst body may be provided with a heater intended only for raising the temperature of the gas supply pipe. These gas introduction pipes are generally arranged at a distance as far as the Knudsen cell.

(Embodiment 3)
Next, a third embodiment of the present invention will be described. In the first embodiment, the modified example, and the second embodiment, one gas introduction pipe 13 with the catalyst body 10 is disposed in the chamber. However, in the third embodiment, a plurality of catalyst bodies 10 are disposed in the same chamber. The attached gas introduction pipe 13 is arranged.

FIG. 19 is a block diagram showing a schematic configuration of a nitride thin film manufacturing apparatus 3 according to Embodiment 3 of the present invention. As shown in FIG. 19, the nitride thin film manufacturing apparatus 3 includes gas introduction pipes 13a to 13c with catalyst bodies 10a to 10c, respectively. NH ₃ and silane are provided from the gas introduction pipes 13a to 13c. (SiH ₄ ) and hydrogen (H ₂ ) are introduced. Compared to the first embodiment and its modification, the embodiment is characterized in that a Knudsen cell for supplying a metal raw material is not used.

As shown in FIG. 19, when NH ₃ is introduced from the gas introduction pipe 13a, NH ₃ is decomposed by the catalyst body 10a, and when SiH ₄ is introduced from the gas introduction pipe 13b, SiH ₄ is decomposed by the catalyst body 10b, When H ₂ is introduced from the gas introduction pipe 13c, the catalyst body 10c decomposes H ₂ and irradiates the substrate 12C.

As a result, irradiation of NH ₃ decomposition species and H ₂ decomposition species onto the substrate 12C is suitable for cleaning the substrate surface. On the other hand, by irradiating NH ₃ decomposition species and SiH ₄ decomposition species, a high-quality silicon nitride (SiN) film can be formed on the substrate 21C. Further, when diborane (B ₂ H ₄ ) is introduced instead of SiH ₄ and the substrate is irradiated with NH ₃ decomposition species and B ₂ H ₄ decomposition species, high-quality boron nitride (BN) is formed on the substrate 21C. A film can be formed. It is possible to simultaneously provide a catalytic decomposition cell for introducing silane and a catalytic decomposition cell for introducing diborane so that both a silicon nitride film and a boron nitride film can be deposited. In this case, a multilayer film of a silicon nitride film and a boron nitride film or a film having a mixed composition can be deposited.

In the third embodiment, by providing the gas introduction pipes 13a to 13c with a plurality of catalyst bodies 10a to 10c, the surface cleaning process of the substrate 21C is performed and a high-quality SiN or BN film is formed. . In the third embodiment, the surface cleaning process of the substrate 21C is performed using the NH ₃ decomposition species and the H ₂ decomposition species. However, the surface cleaning process is performed using only the H ₂ decomposition species. Also good. In addition, the number of the gas introduction pipes 13a to 13c with the catalyst bodies 10a to 10c is three, but it is not necessary to limit to three.

(Embodiment 4)
Next, a fourth embodiment of the present invention will be described. In the third embodiment, a decomposition species is supplied from a catalyst body to a relatively small area substrate to form a desired film on the substrate. In the fourth embodiment, a large area organic substance is formed. A desired film is formed on the film.

  FIG. 20 is a block diagram showing a schematic configuration of the nitride thin film manufacturing apparatus 4 according to the fourth embodiment. As shown in FIG. 20, this nitride thin film manufacturing apparatus 4 includes a chamber 17A for forming a desired film, a gas introduction chamber 13A for introducing a gas into the chamber 17A, and a plurality of catalyst bodies for decomposing the introduced gas. 10A to 10D, an organic film 21D for forming a desired film, rotating rollers 27a and 27b for rotating the organic film 21D to set a new film forming surface, and a heater 20A for heating the organic film 21D to a predetermined temperature And have.

  As described above, by arranging the plurality of catalyst bodies 10A to 10D, the gas introduced from the gas introduction chamber 13A is decomposed by the catalyst bodies 10A to 10D, and a desired film is formed on the organic film 21D having a large area. be able to. Although the plurality of catalyst bodies 10A to 10D are four, it is not necessary to limit the number to four.

(Embodiment 5)
Next, a fifth embodiment of the present invention will be described. In the first to fourth embodiments, the heat of the catalyst body is not shielded, but in this fifth embodiment, a heat shielding plate that performs heat shielding is arranged between the catalyst body and the substrate.

  FIG. 21 is a block diagram showing a schematic configuration of the nitride thin film manufacturing apparatus 5 according to the fifth embodiment. As shown in FIG. 21, the nitride thin film manufacturing apparatus 5 includes a chamber 17C for forming a desired film and a gas introduction chamber 13B for introducing a gas into the chamber 17C. The gas introduction chamber 13B has a gas dispersion plate 130 that uniformly disperses the introduction gas, and the chamber 17C has a radiant heat shielding plate 32 that shields the heat of the catalyst body 10A.

  As shown in FIG. 21, the heat generated by the catalyst body is absorbed by the radiant heat shielding plate 32, and the influence of radiant heat on the substrate can be suppressed. Therefore, film growth can be performed at a low temperature, and a high-quality film is formed on the substrate. It is formed. The radiant heat shielding plate 32 is preferably formed of a high melting point metal like the catalyst body 10.

(Embodiment 6)
Next, Embodiment 6 regarding the manufacturing method will be described. Although the description will be made by taking the forming apparatus of the first embodiment as an example, the present invention can be applied to the forming apparatus of the first embodiment and its modified examples and the second embodiment. In addition, a case description relating to Embodiments 3 and 4 will be given.

  First, as Embodiment 6-1, a substrate surface cleaning step will be described. The substrate is introduced into the chamber 17 from the atmosphere by a load lock mechanism. Even if wet processing is performed on the substrate surface in advance, impurities such as surface oxides cannot be completely removed, and preheating at about 500 ° C. is performed in a load lock mechanism to reduce the amount of impurities. However, since it cannot be completely removed, impurities such as oxide remain on the substrate surface immediately after introduction. The cleaning process of the present invention effectively removes residual impurities including oxygen and carbon on the substrate.

After placing the Si substrate 21 on the holder, the substrate temperature is set to a desired temperature. Next, the cleaning of the surface of the Si substrate is realized by setting the catalyst body 10 to about 1700 ° C., introducing NH ₃ of 10 to 100 sccm, and irradiating the surface of the Si substrate 21. A cleaning effect can be obtained by setting the temperature of the Si substrate 21 to 300 ° C. or higher. In the case of Si, thermal damage is small even at a high substrate temperature. Therefore, it is desirable to set the temperature to 700 ° C. or higher for 10 minutes. Prior to this cleaning process, the Si substrate 21 may be heat-cleaned at a temperature of 700 or more without introducing NH ₃ . By these treatments, the substrate surface can be cleaned.

  When the surface after cleaning when a substrate having a (111) plane orientation is used as the Si substrate 21, a streak pattern is obtained as schematically shown in FIG. FIG. 22 shows an example of observation at 700 ° C., where the superstructure of the Si surface is observed. When the substrate temperature is lowered, the pattern is caused by the Si crystal cycle. These patterns indicate that the surface of the Si substrate 21 is cleaned.

  As described above, when the temperature of the Si substrate 21 is set to 700 ° C. or more and the cleaning process is performed for 10 minutes or more, the reactions (2) and (3) occur on the surface of the Si substrate 21, and the Si substrate 21 and the deposited film The concentration of carbon and oxygen impurities remaining in the interface region can be reduced. These impurities may diffuse thermally through the solid phase in simple high temperature processing. Further, since it may be released into the gas phase and taken into the subsequent deposited film, it is desirable to perform a cleaning process for a relatively long time in an environment irradiated with the decomposition species of the present invention.

Since the above diffusion and reuptake are suppressed, impurities in a region of 10 nm to 50 nm including the interface between the substrate and the thin film can be reduced. When this region is observed by the SIMS method, the amount of oxygen and carbon impurities can be set to a peak value of 1 × 10 ¹⁷ cm ⁻³ or less.

When thermal damage such as a GaAs substrate occurs, the temperature of the substrate 21 needs to be lowered to about 400 ° C. In this case, it is effective to make the cleaning time relatively long. In the case of Embodiments 3 and 4, the cleaning effect can be obtained by flowing only the nitrogen source gas and heating the catalyst body installed in the gas introduction pipe. H ₂ gas may be introduced.

The principle of cleaning the surface of the substrate 21 will be described. When NH ₃ comes into contact with the heated catalyst body 10, the following reaction (1) occurs, and decomposition species NH _X and hydrogen radicals (3-x) H are generated.
NH ₃ → NH _x + (3-x) H (1)
Where x is 0-2
By setting the temperature of the catalyst body 10 to 1700 ° C. or higher, the reaction (1) is promoted. The hydrogen radicals generated here have the effect of effectively removing, removing, and cleaning deposits containing oxygen and carbon from the surface of the substrate 21 by the surface reaction of (2) and (3).
2H + O → H ₂ O (desorption) (2)
4H + C → CH ₄ (elimination) (3)
Since the distance from the catalyst body 10 to the substrate is 10 cm, and the pressure in the reaction vessel is kept small by the effect of the shroud 82, the mean free path of the decomposed species in the reaction vessel is sufficiently large. 21 is effectively reached.

Embodiment 6-2
Next, as Embodiment 6-2, a substrate surface treatment process will be described. Next, the surface treatment of the Si substrate 21 will be described. When 100 sccm of ammonia is introduced while the temperature of the Si substrate 21 is kept at 700 ° C. and the temperature of the catalyst body 10 is set at 300 ° C., the RHEED image changes to a halo pattern as shown in FIG. 23 after about 10 minutes. This indicates that the surface of the Si substrate has been nitrided.

  This surface treatment is one of means for controlling the quality design of a thin film to be deposited, which will be described later. In the case of a GaN deposited film, cubic GaN is obtained at a Si substrate 21 temperature of 500 ° C. or lower when the surface treatment process is performed. When the surface treatment step is not performed and when the substrate temperature is set to 550 ° C. or higher, hexagonal GaN is dominant. In the hexagonal GaN at 550 ° C. or higher, the nitrogen polarity becomes dominant when the surface treatment process is performed. If the intermediate temperature or surface treatment is insufficient, the state of the thin film may be composed of a mixture thereof. Therefore, when the deposition is simply performed, this surface treatment process may not be performed.

  In the case of Embodiments 3 and 4, only the nitrogen source gas is supplied, and the catalyst body attached thereto is set at about 1000 ° C. to achieve nitriding.

Embodiment 6-3
Next, as Embodiment 6-3, a thin film deposition process on a substrate will be described. Furthermore, the catalyst body 10 is set to an arbitrary temperature of 2000 ° C. or less, NH ₃ is introduced at 10 sccm or more, irradiated onto the Si substrate 21 held at 300 ° C. or more, and Knudsen loaded with gallium (Ga). By heating the cell 22a and irradiating the Si substrate 21 with a Ga molecular beam, a deposited film of gallium nitride is obtained.

  The temperature setting of the catalyst body affects the growth temperature. At this time, a nitride deposit is obtained by adjusting the supply amount of the Ga molecular beam. Care must be taken because metal droplets are likely to be generated when the amount of Ga is too large.

Next, a GaN deposition process on the Si substrate 21 will be described. When the Si substrate 21 temperature is set to 550 ° C., NH ₃ is introduced into the reaction chamber at 100 sccm, the catalyst body 10 temperature is set to 700 ° C., and the supply of Ga molecular beam from the Knudsen cell 22a is started, the GaN thin film deposition Will occur. At the Si substrate 21 temperature of 550 ° C. or lower, the RHEED pattern tends to change into a spot shape unless the flow rate of NH ₃ is optimized. This means that the surface flatness of the GaN thin film is deteriorated. Further, by depositing AlN prior to GaN deposition, a flat GaN thin film can be deposited even if the temperature of the Si substrate 21 is set to 700 ° C. or higher.

In the deposition of GaN, the reaction of the NH ₃ catalyst body 10 shown in (1) is somewhat suppressed, so that the etching effect by hydrogen radicals is limited, and the following reaction (4) is promoted on the Si substrate 21. To occur.
NHx + Ga → GaN + xH (4)

When the Ga flux amount was 5 × 10 ⁻⁸ Torr and the Si substrate 21 temperature was 500 ° C., the growth rate of GaN was 0.1 μm / hr, and 0.1 μm of GaN was deposited by this method. As shown in FIG. 24 of the X-ray diffraction results observed when nitriding is not performed, GaN is hexagonal. FIG. 25 shows the PL spectrum. The HeCd laser (325 nm) is weakly excited at about 1 mW / cm ² and has a slit width of 3000 microns. The emission due to the band gap of 385 nm is dominant, and the emission associated with carbon impurities (Yellow emission). ) Is sufficiently suppressed. Also, no carriers due to oxygen impurities are observed, indicating that a high-purity GaN layer is formed.

  In Embodiments 3 and 4, silane and diborane are supplied instead of Ga. The catalyst body temperature of these gas introduction pipes is preferably about 1700 ° C. In the modification of the first embodiment, In and Al are appropriately supplied together with Ga, and multilayer films having various compositions are formed.

Embodiment 6-4
Finally, an etching process will be described as Embodiment 6-4. When the supply of Ga is stopped after depositing the nitride and the temperature of the catalyst body 10 is set to 1700 ° C. or higher with ammonia flowing, etching of the GaN layer occurs. Etching without introducing crystal defects such as N vacancies is possible because the surface partial pressure of N material on the surface is increased due to the contribution of NHx.

In Embodiment 6-4, the Si substrate 21 can be cleaned by disposing the catalyst body 10 at the tip of the opening of the gas inlet tube 13 and efficiently decomposing NH ₃ . Thereafter, high-quality GaN can be formed on the Si substrate 21 by the configuration of the embodiment 6-3.

  Here, etching of the deposited nitride thin film is shown. However, for example, when a GaN epitaxial layer formed by another apparatus such as MOCVD is used as a substrate, or a GaN layer subjected to a dry etching process is used as a substrate. In some cases, it is effective to use the etching process of the present invention for the purpose of removing the damaged layer on the surface.

(Embodiment 7)
Next, an embodiment of a desirable thin film deposition process by a combination of the processes described in Embodiments 6-1 to 4 will be described.

  Therefore, a case where a light emitting element made of a nitride semiconductor is formed on a conductive Si substrate will be described.

(Substrate surface wet treatment)
By performing organic cleaning and hydrofluoric acid treatment as Si substrate pretreatment, a stable surface is formed by cleaning the substrate surface and terminating the Si substrate surface with hydrogen. The attached hydrogen is desorbed by performing a cleaning process in the reaction chamber, and a clean surface can be formed.

(Board mounting on the board holder)
The Si substrate subjected to the wet treatment is attached to a substrate holder made of molybdenum.

(Introduction of the substrate to the equipment)
A substrate holder to which the Si substrate is fixed is introduced into a preparation chamber provided separately from the reaction chamber. In addition to the reaction chamber, the thin film manufacturing apparatus has two chambers, a preparation chamber for introducing a substrate and an introduction chamber for preheating before introduction into the reaction chamber. It is configured not to be exposed to the atmosphere. After introduction into the preparation chamber, the preparation chamber is evacuated to 1 × 10 ⁻⁷ Torr or less by a vacuum pump.

(Preheating)
After the introduction chamber is evacuated, the gate valve is opened and the substrate is transferred to the introduction chamber. Like the reaction chamber, the introduction chamber is not open to the atmosphere and is always maintained at an ultrahigh vacuum of about 1 × 10 ⁻¹⁰ Torr. After transportation, the Si substrate is attached to a substrate holder installed in the introduction chamber, heated to 600 ° C. with a heater, preheated by holding for 30 minutes after reaching 600 ° C., and taken out from the atmosphere Then, remove moisture adhering to the substrate holder. Thereafter, the temperature is lowered to room temperature. This step may be performed in the introduction chamber.

(Introducing the substrate into the reaction chamber)
After the substrate is cooled to room temperature after preheating, the gate valve is opened and the substrate is introduced into the reaction chamber.

(Exhaust: Ultimate vacuum)
The reaction chamber is in a state where liquid nitrogen is introduced into the shroud and is sufficiently cooled, and reaches an ultra high trueness of about 1 × 10 ⁻¹⁰ Torr. The metal raw material is preset to a temperature corresponding to a desired supply amount and is not discharged into the reaction chamber by the shutter.

(Cleaning Step) 700 ° C. Embodiment 6-1
In order to clean the surface of the Si substrate, the substrate temperature is heated to 700 ° C. The surface state is observed in situ by RHEED, and hydrogen attached to the surface is removed, and a pattern resulting from the Si crystal cycle is observed. Thereby, it can confirm that the Si substrate surface was cleaned.

(Surface treatment process) 300 ° C. Embodiment 6-2
In order to nitride the surface, NH ₃ is introduced with the substrate temperature kept at 700 ° C., and the catalyst body temperature is set at 300 ° C. and held. Thereby, it can confirm that it changes to a halo pattern by RHEED and the substrate surface is nitrided.

(Deposition Step 1 Buffer Layer) 650 ° C. AlN Embodiment 6-3
After the surface nitriding treatment, the substrate temperature is lowered to 650 ° C. When the temperature is maintained at 650 ° C., the shutter of the Knudsen cell loaded with Al is opened, and the substrate is irradiated with Al to deposit an AlN buffer layer on the substrate surface.

(Deposition Step 2 n-Clad Layer) 700 ° C. GaN Embodiment 6-3
After the buffer layer is deposited, the substrate temperature is raised to 700 ° C. When the temperature is maintained at 700 ° C., the shutter of the Knudsen cell loaded with Ga is opened, and the substrate is irradiated with Ga to laminate the GaN thin film.

(Deposition Step 3 QW Layer) 500 ° C. InGaN Embodiment 6-3
After the GaN layer is deposited, the substrate temperature is lowered to 500 ° C. When the temperature is maintained at 500 ° C., the shutter of the Knudsen cell loaded with In and Ga is opened, and the substrate is irradiated with In and Ga to deposit an InGaN thin film.

(Deposition Step 4 p-Clad Layer) 600 ° C. GaN Embodiment 6-3
After the InGaN layer is stacked, the substrate temperature is raised to 600 ° C. When the temperature is maintained at 600 ° C., the shutter of the Knudsen cell loaded with Ga is opened, and the substrate is irradiated with Ga to deposit a GaN thin film.

(Deposition Step 5 Contact Layer) 700 ° C. GaN Embodiment 6-3
After the GaN layer is stacked, the substrate temperature is raised to 700 ° C. When the temperature is maintained at 700 ° C., the shutter of the Knudsen cell in which Ga is loaded is opened, and the substrate is irradiated with Ga to deposit a GaN thin film.

(take out)
After the thin film is deposited, the substrate temperature is lowered to 150 ° C. which is the holding temperature of the substrate holder. The temperature of the Knudsen cell of the metal raw material used is also lowered to 150 ° C. which is the holding temperature. When the substrate temperature reaches 150 ° C., the gate valve is opened and the substrate holder is transferred to the introduction chamber. Furthermore, it is transported to the preparation room, and the preparation room is leaked by introducing nitrogen into the atmospheric pressure. When atmospheric pressure is reached, the substrate holder is removed from the preparation chamber.

(Embodiment 8)
Next, an eighth embodiment will be described. In the eighth embodiment, a case where a field effect transistor made of a nitride semiconductor is formed on an insulating GaN substrate will be described.

(Substrate surface wet treatment)
The insulating GaN substrate is etched using organic cleaning and hydrochloric acid and sulfuric acid solutions.

(Board mounting on the board holder)
A wet-processed GaN substrate is attached to a substrate holder made of molybdenum.

(Introduction of the substrate to the equipment)
A substrate holder to which the GaN substrate is fixed is introduced into a preparation chamber provided separately from the reaction chamber. In addition to the reaction chamber, the thin film manufacturing apparatus has two chambers, a preparation chamber for introducing a substrate and an introduction chamber for preheating before introduction into the reaction chamber. It is configured not to be exposed to the atmosphere. After introduction into the preparation chamber, the preparation chamber is evacuated to 1 × 10 ⁻⁷ Torr or less by a vacuum pump.

(Preheating)
After the introduction chamber is evacuated, the gate valve is opened and the substrate is transferred to the introduction chamber. Like the reaction chamber, the introduction chamber is not open to the atmosphere and is always maintained at an ultrahigh vacuum of about 1 × 10 ⁻¹⁰ Torr. After transporting, the substrate is attached to a substrate holder installed in the introduction chamber, heated to 600 ° C. with a heater, preheated by holding for 30 minutes after reaching 600 ° C., and taken out from the atmosphere Also, remove moisture adhering to the substrate holder. Thereafter, the temperature is lowered to room temperature.

(Introducing the substrate into the reaction chamber)
After the substrate is cooled to room temperature after preheating, the gate valve is opened and the substrate is introduced into the reaction chamber.

(Exhaust: Ultimate vacuum)
The reaction chamber is in a state where liquid nitrogen is introduced into the shroud and is sufficiently cooled, and reaches an ultra high trueness of about 1 × 10 ⁻¹⁰ Torr. The metal raw material is preset to a temperature corresponding to a desired supply amount and is not discharged into the reaction chamber by the shutter.

(Cleaning Step) 700 ° C. Embodiment 6-1
In order to clean the surface of the GaN substrate, the substrate temperature is heated to 700 ° C. The surface state is observed in situ by RHEED, and hydrogen attached to the surface is removed, and a pattern due to the GaN crystal period is observed. Thereby, it can confirm that the GaN substrate surface was cleaned.

(Etching step) 300 ° C. Embodiment 6-4
In order to etch the surface of the GaN substrate, the substrate temperature is set to 550 ° C. When the substrate temperature is maintained at 550 ° C., NH ₃ is introduced, and the catalyst body temperature is set to 1700 ° C. and maintained. Thereby, the GaN substrate surface is etched. RHEED remains a streak pattern.

(Deposition Step 1 High Purity GaN Layer) 700 ° C. Embodiment 6-3
After etching the GaN substrate, the substrate temperature is raised to 700 ° C. When the temperature is maintained at 700 ° C., the shutter of the Knudsen cell loaded with Ga is opened, and the substrate is irradiated with Ga to deposit a GaN thin film on the substrate surface.

(Deposition Step 2 AlGaN Layer) 700 ° C. Embodiment 6-3
After depositing the GaN layer, with the substrate temperature kept at 700 ° C., the shutter of the Knudsen cell loaded with Al and Ga is opened, and the substrate is irradiated with Al and Ga to deposit an AlGaN thin film on the substrate surface.

(take out)
After the thin film is deposited, the substrate temperature is lowered to 150 ° C. which is the holding temperature of the substrate holder. The temperature of the Knudsen cell of the used metal raw material is also lowered to a holding temperature of 150 ° C. When the substrate temperature reaches 150 ° C., the gate valve is opened and the substrate holder is transferred to the introduction chamber. Furthermore, it is transported to the preparation room, and the preparation room is leaked by introducing nitrogen into the atmospheric pressure. When atmospheric pressure is reached, the substrate holder is removed from the preparation chamber.

(Embodiment 9)
Next, Embodiment 9 will be described. In the ninth embodiment, a case where a passivation film made of a nitride insulator is formed on an organic EL element will be described.

(Substrate surface wet treatment)
(Board mounting on the board holder)
An organic EL element is attached to a substrate holder.

(Introduction of the substrate to the equipment)
A substrate holder to which the organic EL element is fixed is introduced into a preparation chamber provided separately from the reaction chamber. In addition to the reaction chamber, the thin film manufacturing apparatus has two chambers, a preparation chamber for introducing a substrate and an introduction chamber for preheating before introduction into the reaction chamber. It is configured not to be exposed to the atmosphere. After introduction into the preparation chamber, the preparation chamber is evacuated to 1 × 10 ⁻⁴ Torr or less by a vacuum pump.

(Preheating)
After the introduction chamber is evacuated, the gate valve is opened and the substrate is transferred to the introduction chamber. Like the reaction chamber, the introduction chamber is not opened to the atmosphere and is always maintained at a high vacuum of about 1 × 10 ⁻⁷ Torr. After transportation, the organic EL substrate was attached to a substrate holder installed in the introduction chamber, heated to 150 ° C. with a heater, preheated by holding for 30 minutes after reaching 150 ° C., and taken out from the atmosphere. Remove moisture etc. adhering to the substrate and the substrate holder. Thereafter, the temperature is lowered to room temperature. This step may be performed in the introduction chamber. A two-room load lock system can also be used.

(Introducing the substrate into the reaction chamber)
After the substrate is cooled to room temperature after preheating, the gate valve is opened and the substrate is introduced into the reaction chamber.

(Exhaust: Ultimate vacuum)
The reaction chamber is in a state where liquid nitrogen is introduced into the shroud and is sufficiently cooled, and reaches a high true value of about 1 × 10 ⁻⁷ Torr.

(Cleaning Step) 150 ° C. Embodiment 6-1
In order to clean the surface of the organic EL substrate, the substrate temperature is heated to 150 ° C. Here, by setting the temperature of the arranged catalytic body to the gas introduction openings can be introduced with H ₂ to 1200 ° C., by flowing of H _2, the atomic hydrogen by catalytic cracking reaction of the catalyst and H ₂ The organic EL substrate surface can be cleaned by generating and irradiating the substrate surface.

Here, by setting the temperature of the catalyst body arranged in the gas introduction opening where NH ₃ can be introduced to 1700 ° C. and flowing NH ₃ , atomic hydrogen is generated and irradiated onto the substrate surface. It is also possible to clean the surface of the organic EL substrate.

(Surface treatment step) 150 ° C. Embodiment 6-2
In order to surface-treat the organic EL substrate, NH ₃ is introduced and held while the substrate temperature is kept at 150 ° C. Thereby, the organic EL substrate surface can be nitrided.

(Deposition Process SiN) 150 ° C. Embodiment 6-3
After the surface treatment of the organic EL substrate, the temperature of the catalyst body arranged in the gas introduction part where SiH ₄ can be introduced can be set to 1700 ° C. and NH ₃ can be introduced while maintaining the substrate temperature at 150 ° C. respectively set the temperature of the disposed catalyst bodies 1200 ° C. in, SiH ₄ and by introducing NH _3, and the organic EL decomposition species SiH ₄ and NH ₃ is produced by catalytic cracking with the catalyst body, respectively By irradiating the substrate, a SiN thin film is deposited.

(take out)
After thin film deposition, gas introduction is stopped and the temperature of the catalyst body is lowered to room temperature. At the same time, the substrate temperature is lowered to the room temperature of the substrate holder. When the substrate temperature falls, the gate valve is opened and the substrate holder is transferred to the introduction chamber. Furthermore, it is transported to the preparation room, and the preparation room is leaked by introducing nitrogen into the atmospheric pressure. When atmospheric pressure is reached, the substrate holder is removed from the preparation chamber.

(Embodiment 10)
Next, Embodiment 10 will be described. In the tenth embodiment, an embodiment of a nitride semiconductor thin film stack to be formed will be described.

  A nitride thin film was formed using the Si substrate 21, but germanium, silicon carbide, gallium arsenide, gallium phosphide, indium phosphide, zinc selenide, cadmium sulfide, gallium nitride, aluminum nitride, sapphire, zinc oxide, magnesium oxide, Any of the single crystal substrates may be used. The Si substrate 21 may be formed using quartz glass, borosilicate glass, or aluminosilicate glass as a raw material.

It is a multilayer film of AlGaInN thin films of various compositions deposited on a single crystal substrate, and the carbon and oxygen impurity concentration at the interface between the substrate and the thin film is 1 × 10 ¹⁷ cm ⁻³ or less.

A multilayer film of AlGaInN thin films of various compositions deposited on a single crystal substrate. The carbon and oxygen impurity concentration at the interface between the substrate and the thin film is 1 × 10 ¹⁷ cm ⁻³ or less. At least one of the multilayer films of the AlGaInN thin film is a single crystal. You may perform a cleaning process before thin film deposition. Surface treatment may be performed before thin film deposition. Moreover, you may perform an etching process before thin film deposition. Further, the buffer layer may be formed before the thin film is deposited. When there is a buffer layer, the carbon and oxygen impurity concentrations at the interface between the substrate and the thin film are 1 × 10 ¹⁷ cm ⁻³ or less including the buffer layer.

A multilayer film of AlGaInN thin films of various compositions deposited on a single crystal substrate. The carbon and oxygen impurity concentration at the interface between the substrate and the thin film is 1 × 10 ¹⁷ cm ⁻³ or less. At least one of the multilayered AlGaInN thin films is polycrystalline. You may perform a cleaning process before thin film deposition. Surface treatment may be performed before thin film deposition. Moreover, you may perform an etching process before thin film deposition. Further, the buffer layer may be formed before the thin film is deposited. When there is a buffer layer, the carbon and oxygen impurity concentrations at the interface between the substrate and the thin film are 1 × 10 ¹⁷ cm ⁻³ or less including the buffer layer.

A multilayer film of AlGaInN thin films of various compositions deposited on a single crystal substrate. The carbon and oxygen impurity concentration at the interface between the substrate and the thin film is 1 × 10 ¹⁷ cm ⁻³ or less. At least one of the multilayer films of the AlGaInN thin film is amorphous. You may perform a cleaning process before thin film deposition. Surface treatment may be performed before thin film deposition. Moreover, you may perform an etching process before thin film deposition. Further, the buffer layer may be formed before the thin film is deposited. When there is a buffer layer, the carbon and oxygen impurity concentrations at the interface between the substrate and the thin film are 1 × 10 ¹⁷ cm ⁻³ or less including the buffer layer.

A multilayer film of AlGaInN thin films of various compositions deposited on a single crystal substrate. The carbon and oxygen impurity concentration at the interface between the substrate and the thin film is 1 × 10 ¹⁷ cm ⁻³ or less. At least one layer of the multilayer film of the AlGaInN thin film is cubic. You may perform a cleaning process before thin film deposition. Surface treatment may be performed before thin film deposition. Moreover, you may perform an etching process before thin film deposition. Further, the buffer layer may be formed before the thin film is deposited. When there is a buffer layer, the carbon and oxygen impurity concentrations at the interface between the substrate and the thin film are 1 × 10 ¹⁷ cm ⁻³ or less including the buffer layer.

A multilayer film of AlGaInN thin films of various compositions deposited on a single crystal substrate. The carbon and oxygen impurity concentration at the interface between the substrate and the thin film is 1 × 10 ¹⁷ cm ⁻³ or less. At least one of the multilayer films of the AlGaInN thin film is hexagonal. You may perform a cleaning process before thin film deposition. Surface treatment may be performed before thin film deposition. Moreover, you may perform an etching process before thin film deposition. Further, the buffer layer may be formed before the thin film is deposited. When there is a buffer layer, the carbon and oxygen impurity concentrations at the interface between the substrate and the thin film are 1 × 10 ¹⁷ cm ⁻³ or less including the buffer layer.

(Embodiment 11)
Next, Embodiment 11 will be described. In the eleventh embodiment, an electronic device epi will be described. An embodiment for producing an electronic device on a GaN substrate or a GaN epitaxial layer will be described.

  Here, a structure for manufacturing a planar FET will be described. A high-resistance GaN epitaxial layer is formed in advance on a sapphire substrate to form a template substrate.

  The high-resistance GaN layer is highly pure and desirably has a thickness of about 1 to 3 μm. Instead of the GaN layer on sapphire, a GaN substrate can be used.

In Embodiment 11, no impurities remain at the interface between the GaN substrate layer and the high-purity GaN layer formed in Embodiments 1 and 2 by applying the cleaning method of Embodiment 6-1. The GaN substrate may be processed by a technique such as dry etching. In this case, the damaged layer is removed by applying the etching method of Embodiment 6-4. When the interface between the substrate and the growth layer in this embodiment is measured by SIMS, the amount of oxygen and carbon impurities detected in the interface region is 1 × 10 ¹⁷ cm ⁻³ or less. A high-quality Si-doped n-type GaN layer is formed to 0.1 μm on this interface by the method of Embodiment 6-3, and serves as an electron transit layer. An undoped GaN layer may be formed to have a thickness of 0.1 μm, and an undoped AlGaN layer may be continuously stacked for 20 to 30 nm to generate two-dimensional electrons due to a polarization effect, and this may be used as a HEMT configuration using this as a carrier. In this case, the AlN molar composition of the AlGaN layer is set to 0.2 to 0.3.

Embodiment 12
Next, Embodiment 12 will be described. In the twelfth embodiment, a configuration of an organic EL element formed using the apparatus of the third embodiment using a SIN film as a surface protective film will be described.

  In this embodiment (FIG. 26), the material constituting the organic EL element is such that the EL element is formed on an acrylic transparent film having a thickness of 0.5 mm. In addition to this, a plastic film such as glass, silicon, polyimide, polyphthalate or the like can be used for the substrate. First, aluminum of an anode is formed on a substrate by 0.2 μm vacuum vapor deposition, and an organic film of an electron transport layer, a light emitting layer, and a hole transport layer is sequentially deposited thereon by a general vapor deposition or coating method. The light emitting layer is appropriately selected according to the selection of the light emission color. A general fluorescent or phosphorescent light emitting polymer having light emission characteristics in the visible range can be used. Indium tin oxide (ITO) is formed on the upper layer of the hole transport layer. A zinc oxide-based anode may also be used. In the twelfth embodiment, a 0.1 μm SiN film is laminated as a protective film on the uppermost layer of the organic EL element that has already been formed up to the ITO film. Wiring extraction from the anode and cathode may also be made in advance. When the production method of the present invention is used, the substrate temperature can be set to 150 ° C. or lower during deposition, and thus an organic EL element with a SiN protective film that does not warp due to shrinkage of the film or a difference in thermal expansion coefficient is configured. The warpage was almost flat with a radius of curvature of 100 cm or more for an element size of 10 cm square (FIG. 27). The dent amount at the center of the element can be about 25 μm or less. Therefore, a thin self-supporting display element can be configured without using a glass substrate or the like. In addition to this, conventionally, it has been necessary to increase the temperature during the deposition of the passivation film, and there has been a problem that unevenness occurs in the organic EL film or the element resistance increases. In Embodiment 12, the surface treatment of Example 6-2 is performed on the film prior to the deposition of Example 6-3, and the adhesion of the SiN film is improved. The composition of the SiN film is a composition having a Si / N ratio of 0.75 to 0.9 which is slightly Si-rich with respect to the stoichiometric composition. The thickness of the SiN film is 0.05 to 0.5 μm, and an effect as a protective film can be obtained. In the organic EL element having this configuration, dense SiN serves as a protective film and prevents intrusion of moisture and the like from the atmosphere, so that an organic EL element that can be used for a long time can be obtained.

Example 1
A specific nitride thin film manufacturing apparatus will be described. As a vacuum pump for reducing the reaction chamber to a predetermined pressure, an ion pump, a titanium sublimation pump, a turbo molecular pump, and a rotary pump are provided. The ion pump and the titanium sublimation pump are used to improve the degree of vacuum before flowing the raw material gas.

  A substrate holder for holding the substrate is disposed in the reaction chamber, and the holder has a heater and a cooling pipe for heating the substrate to a desired temperature. The substrate temperature is monitored by using an installed thermocouple or by observing thermal radiation from the substrate with a pyrometer. Further, the substrate holder has a rotation mechanism, and can rotate during the thin film deposition. The substrate is attached to a substrate holder made of molybdenum, transported to the reaction chamber, and fixed to the substrate holder.

  A shroud is disposed on the side wall of the reaction chamber, around the source gas cell, and in the vicinity of the titanium pump, and the reaction chamber can be kept at a high vacuum by adsorbing the released gas by flowing and cooling liquid nitrogen. Among these, the shroud provided on the side wall of the reaction chamber can adsorb undecomposed NH 3 and prevent the reaction chamber from staying.

The reaction chamber is made of tungsten having a purity of 99.999%, which disposes the introduced NH _3, which is arranged in a portion substantially coincident with the opening of the gas introduction tube and the gas introduction tube for introducing NH ₃ as the nitrogen source gas. A catalyst body is installed. The catalyst body is connected to a conductive wire formed of silver-coated copper, and is set to a desired temperature by energization using a heating power source installed outside the thin film deposition apparatus.

The distance between the substrate and the catalyst body is 10 cm. Ammonia (NH ₃ ), which is a nitrogen gas raw material, is adjusted to an appropriate pressure by a pressure controller from a cylinder stored in the cylinder cabinet, and a desired flow rate is introduced into the reaction chamber via a flow rate controller (MFC). Is done.

Gallium (Ga), indium (In), and aluminum (Al) are used as metal materials, and silicon (Si), magnesium (Mg), and beryllium (Be) are heated as a dopant material and emitted as molecular beams. It has a Knudsen cell in the reaction chamber.
The reaction chamber also has a reflection high-energy electron diffraction electron gun (RHEED) that can be observed in-situ during deposition, a screen, and a quadrupole mass that can detect residual gas in the chamber. Analyzer (QMS).

(Example 2)
A specific method for manufacturing a nitride thin film will be described with reference to FIGS. FIG. 28 is a process diagram for depositing a GaN thin film on a Si substrate. As shown in FIG. 28, the Si substrate is heated to 800 ° C. and held for 30 minutes. As a result, the Si substrate surface is cleaned.

Here, by introducing 100 sccm of NH ₃ at 300 ° C. and maintaining the heating catalyst temperature at 1700 ° C. for 10 minutes, the surface of the Si substrate is similarly cleaned. A nitriding treatment may be performed after the Si substrate surface cleaning step. The nitriding treatment enables the deposition of a GaN thin film having a cubic structure on the Si substrate.

Thereafter, the temperature of the Si substrate is lowered to 500 ° C., NH ₃ is introduced at 100 sccm, the heating catalyst temperature is set to 1200 ° C., the Knudsen cell is heated, the Ga flux amount is set to 5 × 10 ⁻⁸ Torr, and held for 1 hour. . At this time, the pressure in the chamber is about 1 × 10 ⁻⁵ Torr, and the growth rate of the GaN thin film is about 0.1 μm / hr.

  Here, the GaN thin film deposition may be performed at a catalyst body temperature of 1200 ° C. or less. Further, instead of using nitrogen supply by ammonia and a catalyst body, nitrogen may be supplied by a nitrogen plasma gun.

  By this thin film deposition, GaN having a thickness of 100 nm was formed on the Si substrate, and X-ray diffraction (XRD) analysis and photoluminescence (PL) analysis were performed on the GaN thin film. FIG. 24 shows the XRD result of the GaN thin film on the Si substrate. As shown in FIG. 24, it can be seen that a hexagonal (wurzeite) GaN thin film is deposited.

  FIG. 25 shows the PL result on the Si substrate. As shown in FIG. 25, a strong blue peak is observed in the vicinity of a wavelength of 385 nm, and light emission due to impurities (Yellow Band) is not observed, indicating that a high-quality GaN thin film is deposited.

  The substrate is not limited to silicon but germanium, gallium arsenide, indium phosphide, zinc selenide, cadmium sulfide, zinc sulfide, gallium nitride, and aluminum nitride can be used for the same GaN thin film deposition.

  As a thin film to be deposited, any one of binary (AlN, InN), ternary (AlGaN, AlInN, InGaN), and quaternary (AlInGaN) other than GaN by using at least one kind of metal raw material, Al, In or Ga. A single layer film or a multilayer film thereof can also be deposited.

(Example 3)
FIG. 29 is a process diagram for depositing an InGaN SQW (Single Quantum Well) structure on a Si substrate. It implemented using the said nitride semiconductor device. As shown in FIG. 29, the substrate temperature is heated to 300 ° C., NH ₃ is introduced at 100 sccm, the tungsten catalyst body temperature is maintained at 1700 ° C. for 30 minutes, and the surface is cleaned.

At this time, thermal cleaning may be used by raising the substrate temperature to 800 ° C. and holding it for 30 minutes. After cleaning the surface, temperature control is performed, the substrate temperature is heated to 800 ° C., and when the substrate temperature is held at 800 ° C., NH ₃ is introduced at 100 sccm, and the substrate surface is held for 10 minutes. Nitriding may be performed.

The substrate temperature is heated to 550 ° C. When the substrate is held at 550 ° C., the Knudsen cell is heated in advance to open the shutter of the Al cell whose flux amount is set to 5 × 10 ⁻⁸ Torr, and the substrate is irradiated with Al and held for 10 minutes. As a result, an AlN buffer layer of about 10 nm is deposited on the substrate.

After the buffer layer is deposited, temperature control is performed to bring the substrate temperature to 800 ° C. When the substrate temperature is kept at 800 ° C., the Knudsen cell is heated in advance to open the shutter of the Ga cell whose flux amount is set to 1 × 10 ⁻⁷ Torr, and the substrate is irradiated with Ga and held for 30 minutes. . As a result, a GaN thin film is laminated about 100 nm.

After the GaN thin film is deposited, temperature control is performed to bring the substrate temperature to 550 ° C. When the substrate temperature is maintained at 550 ° C., the shutter of the Knudsen cell loaded with In and Ga is opened, and the substrate is irradiated with In and Ga and held for 15 minutes. At this time, the amount of In flux is 5 × 10 ⁻⁸ Torr, and the amount of Ga flux is 5 × 10 ⁻⁸ Torr. As a result, an InGaN thin film having an In composition of 5% is laminated to about 20 nm.

After the InGaN thin film is stacked, temperature control is performed and the substrate temperature is heated to 800 ° C. When the substrate temperature is held at 800 ° C., the Knudsen cell is heated in advance to open the shutter of the Ga cell whose flux amount is set to 1 × 10 ⁻⁷ Torr, and the substrate is irradiated with Ga and held for 15 minutes. . As a result, a GaN thin film is laminated by 50 nm.

After the GaN thin film is deposited, the shutter of the Knudsen cell loaded with Ga is closed, NH ₃ is stopped, substrate heating is stopped, and the substrate is returned to room temperature. As a result, a GaN / InGaN / GaN laminated film is deposited on the substrate.

  The laminated film was subjected to X-ray diffraction and photoluminescence analysis. FIG. 30 shows the XRD result of the laminated film having the InGaN SQW structure on the Si substrate. As shown in FIG. 30, it was found that a hexagonal GaN thin film and an InGaN thin film with an In composition of 5% were deposited.

  FIG. 31 shows the photoluminescence result of the laminated film having the InGaN SQW structure on the Si substrate. As shown in FIG. 31, light emission from GaN near 380 nm and InGaN near 400 nm was observed. Moreover, light emission (Yellow Band) due to impurities is not observed, and it can be seen that a high-quality GaN thin film is deposited.

When the deposited thin film was analyzed by secondary ion mass spectrometry (SIMS), the concentration of carbon and oxygen existing in the vicinity of the interface between the deposited thin film containing the AlN buffer layer and the substrate was 1 × 10 ¹⁷ cm ⁻³ or less. I understood that.

  In the deposition of the laminated film having the InGaN SQW structure, the catalyst body temperature may be 2000 ° C. or lower. Further, instead of using nitrogen supply by ammonia and a catalyst body, nitrogen may be supplied by a nitrogen plasma gun.

  In the laminated film of the InGaN SQW structure, an n-type Si conductive substrate is used as a substrate, a lower GaN thin film is n-type doped, and an upper GaN thin film is p-type doped nitride thin film. An ohmic contact is formed by depositing electrodes (Ni / Au) on the top and bottom of the substrate by a vacuum deposition method, thereby realizing a light emitting device.

  In the laminated film of the InGaN SQW structure, a p-type Si conductive substrate is used as a substrate, a lower GaN thin film is p-type doped, and an upper GaN thin film is n-type doped nitride thin film. An ohmic contact is formed by depositing electrodes (Ni / Au) on the top and bottom of the substrate by a vacuum deposition method, thereby realizing a light emitting device.

  In the stacked film of the InGaN SQW structure, the well layer and the barrier layer of the quantum well structure are binary (GaN, AlN, InN), ternary (AlGaN) by using at least one kind of metal material, Al, In, or Ga. , AlInN, InGaN), or a quaternary (AlInGaN) combination of nitride semiconductors, and may have a MQW structure (Multi Quntum Well).

Example 4
A SiN thin film manufacturing apparatus will be described on an organic film. As a vacuum pump for reducing the reaction chamber to a predetermined pressure, an ion pump, a titanium sublimation pump, a turbo molecular pump, and a rotary pump are provided. The ion pump and the titanium sublimation pump are used to improve the degree of vacuum before flowing the raw material gas.

  A substrate holder for holding the substrate is disposed in the reaction chamber, and the holder has a heater and a cooling pipe for heating the substrate to a desired temperature. The substrate temperature is monitored by using an installed thermocouple or by observing thermal radiation from the substrate with a pyrometer. Further, the substrate holder has a rotation mechanism, and can rotate during the thin film deposition. The substrate is attached to a substrate holder made of molybdenum, transported to the reaction chamber, and fixed to the substrate holder.

A shroud is disposed on the side wall of the reaction chamber, around the source gas cell, and in the vicinity of the titanium pump, and the reaction chamber can be kept at a high vacuum by adsorbing the released gas by flowing and cooling liquid nitrogen. Among them, the shroud provided on the side wall of the reaction chamber can adsorb undecomposed NH ₃ and prevent the reaction chamber from staying.

In the reaction chamber, two gas introduction pipes for introducing NH ₃ which is a nitrogen source gas and SiH ₄ which is a silicon source gas, and the gas introduction pipes are arranged at portions substantially coincident with the openings of the gas introduction pipes. A catalyst body made of tungsten having a purity of 99.999% for dissociating the introduced NH ₃ is installed. The catalyst body is connected to a conductive wire formed of silver-coated copper, and is set to a desired temperature by energization using a heating power source installed outside the thin film deposition apparatus. The distance between the substrate and the catalyst body is 10 cm.

Ammonia (NH ₃ ), which is a nitrogen gas raw material, is adjusted to an appropriate pressure by a pressure controller from a cylinder stored in the cylinder cabinet, and a desired flow rate is introduced into the reaction chamber via a flow rate controller (MFC). Is done.

Silane (SiH ₄ ), which is a silicon raw material, is adjusted to an appropriate pressure by a pressure controller from a cylinder stored in a cylinder cabinet, and a desired flow rate is introduced into the reaction chamber via a flow rate controller (MFC). The

  The reaction chamber also has a reflection high-energy electron diffraction electron gun (RHEED) that can be observed in-situ during deposition, a screen, and a quadrupole mass that can detect residual gas in the chamber. Analyzer (QMS).

(Example 5)
A method for producing a SiN thin film on an organic film will be described. First, the organic film substrate is heated to 150 ° C. At that time, a heater and water cooling are used for temperature control. When the temperature is maintained at 150 ° C., 20 sccm of NH ₃ is introduced with the tungsten catalyst body temperature heated to 1700 ° C., and the surface is maintained for 10 minutes. SiH ₄ and NH ₃ are each provided with a gas introduction part having a tungsten catalyst body in separate openings, and when the substrate is held at 150 ° C., SiH ₄ is introduced at 10 sccm and NH ₃ is introduced at 100 sccm. The tungsten catalyst body temperature at the opening of the gas introduction part for introducing NH ₃ is heated to about 1200 ° C., and the tungsten catalyst body temperature at the opening of the gas introduction part for introducing SiH ₄ is heated to 1700 ° C. ₄ is introduced to decompose NH ₃ and SiH ₄ respectively. The pressure in the reaction chamber is about 1 × 10 ⁻⁵ Torr. An SiN thin film was deposited to a thickness of 100 nm by irradiating an organic film substrate with the decomposition species decomposed by these heating catalyst bodies.

  The deposited thin film was found to have excellent flatness and a warp of 1 mm or less. In addition, it has a wide range of application examples because it prevents moisture from the outside and has high scratch strength on the surface.

  By using a film in which an organic EL element in which an electrode and a wiring are arranged in advance before deposition of the protective film is used as the organic film, the deposited thin film is used as a gas barrier protective film of the organic EL element. Used.

(Example 6)
A modification of the substrate surface cleaning step will be described below. A hydrofluoric acid treatment was performed using the Si substrate as a pretreatment, and the surface of the Si substrate terminated with hydrogen was introduced into the chamber. When the Si substrate is heated to about 300 ° C. and maintained at 300 ° C., NH ₃ is introduced at 100 sccm, the tungsten catalyst body temperature is set to 1700 ° C. and held for 10 minutes. As a result, it was found that the surface was cleaned and a streak pattern was formed by RHEED. The substrate temperature may be 300 ° C. or higher. The catalyst body temperature may be 1200 ° C. or more and 2000 ° C. or less. The gas may be hydrogen, hydrazine or hydrogen azide.

  The substrate is not limited to silicon, but may be a single crystal of germanium, gallium arsenide, gallium phosphide, indium phosphide, zinc selenide, cadmium sulfide, zinc sulfide, gallium nitride, and aluminum nitride. Each substrate is preferably pretreated with the desired organic cleaning and wet etching prior to introduction into the chamber.

(Example 7)
A modification of the nitriding process on the substrate surface will be described below. A hydrofluoric acid treatment was performed using the Si substrate as a pretreatment, and the surface of the Si substrate terminated with hydrogen was introduced into the chamber. When the Si substrate is heated, hydrogen on the surface of the Si substrate is removed and the RHEED pattern becomes a streak. After heating to about 800 ° C. and holding for about 30 minutes, when the temperature is held at 800 ° C., NH ₃ is introduced at 100 sccm and held for 30 minutes. As a result, it was found by RHEED observation that the Si substrate surface was nitrided to form a halo pattern. The substrate temperature may be 800 ° C. or lower. The substrate is not limited to silicon, and may be a single crystal of gallium arsenide, gallium phosphide, indium phosphide, zinc selenide, cadmium sulfide, zinc sulfide, gallium nitride, or aluminum nitride. Each substrate is preferably pretreated with the desired organic cleaning and wet etching prior to introduction into the chamber.

(Example 8)
A modification of the nitride thin film etching process will be described below. The GaN thin film on the Si substrate is heated to a substrate temperature of 550 ° C., and when it is held at 550 ° C., 100 sccm of NH ₃ is introduced and the heated catalyst body temperature is set to 1700 ° C. and held for 1 hour. This etched the GaN thin film about 100 nm. The catalyst body temperature may be 1700 ° C. or more and 2000 ° C. or less. The substrate is not limited to silicon, and may be a single crystal of gallium arsenide, gallium phosphide, indium phosphide, zinc selenide, cadmium sulfide, zinc sulfide, gallium nitride, or aluminum nitride. The deposited film may also be a nitride thin film containing Al, In, Ga, or a combination thereof and a multilayer film thereof.

1, 1A, 2, 3, 4, 5 Thin film production apparatus 10, 10A, 10B, 10C, 10D, 10E Catalyst 11a, 11b Conductor 12 Heating power source 13, 13a, 13b, 13c Gas introduction pipe 13A Gas introduction chamber 14a, 14b, 32a, 32b, 32c Valve 15 MFC
16, 31 cylinder 17, 17A, 17B chamber 18 vacuum pump 19, 19B substrate holder 19A film holder 20, 20A, 20B heater 21 Si substrate 21B, 21C, 21E, 21F substrate 21D organic film 22 radiant heat shielding plate 22a, 22b, 22c Knudsen Cell 23 QMS
24 RHEED
25 Screen 27a, 27b Rotating roller 28 Inductive coil 29 Power supply 29a, 29b, 29c Bubbler 30a, 30b, 30c Organometallic raw material 33 Organometallic gas raw material generating part 81 Refrigerant supply pipe 82 Shroud 83 Gas inlet 84 Bellows 85 Guide 86 Screw 87 Handle 130 Gas dispersion plate

Claims (18)

A raw material which is provided in a thin film manufacturing apparatus for vapor-depositing a thin film on a substrate in a reaction chamber under reduced pressure, and decomposes one or more kinds of raw material gases used as the raw material of the thin film to generate decomposition species of the raw material gas A gas decomposition mechanism,
One or a plurality of source gas introducing means for introducing the source gas into the reaction chamber through the opening, the opening communicating with the reaction chamber;
A catalyst body for decomposing a raw material gas disposed in a state of being displaced closer to the substrate side than an opening surface on the reaction chamber side in the opening, and in a state of being close to the opening;
Catalyst body heating means for heating the catalyst body by energizing the catalyst body;
A raw material gas decomposition mechanism comprising:   2. The raw material gas decomposition mechanism according to claim 1, wherein the catalyst body is made of any one of a refractory metal, a refractory metal compound, and a composite of a thin film constituent raw material and a refractory material.   The raw material gas decomposition mechanism according to claim 1, wherein the catalyst body is tungsten (W) having a purity of 99.99% or more.   The raw material gas decomposition mechanism according to claim 1, wherein the catalyst body has a coil shape, a wire shape, a net shape, a ring shape, a sheet shape, or a shape obtained by combining these shapes.   2. The source gas decomposition mechanism according to claim 1, wherein the source gas introduction unit has an opening area varying unit that varies an area of the opening surface.   The source gas decomposition mechanism according to claim 1, wherein the source gas introduction unit includes a variable unit that varies a distance from the substrate.   2. The source gas decomposition mechanism according to claim 1, wherein the source gas introduction means has a gas dispersion plate inside the opening surface. When a thin film is vapor-deposited on a substrate in a reaction chamber under reduced pressure, the thin film that decomposes one or more kinds of raw material gases as raw materials of the thin film by a raw material gas decomposition mechanism to generate decomposition species of the raw material gas Manufacturing equipment,
The raw material gas decomposition mechanism is
One or a plurality of source gas introducing means for introducing the source gas into the reaction chamber through the opening, the opening communicating with the reaction chamber;
A catalyst body for decomposing a raw material gas disposed in a state of being displaced closer to the substrate side than an opening surface on the reaction chamber side in the opening, and in a state of being close to the opening;
Catalyst body heating means for heating the catalyst body by energizing the catalyst body;
A thin film manufacturing apparatus comprising:   The thin film manufacturing apparatus according to claim 8, wherein the catalyst body is disposed such that a distance between the catalyst body and the substrate is 1 cm or more and 10 cm or less.   9. The thin film manufacturing apparatus according to claim 8, further comprising metal raw material introduction means for heating the metal and irradiating the substrate with the metal as a molecular beam.   The thin film manufacturing apparatus according to claim 8, further comprising a radiant heat shielding plate between the catalyst body and the substrate. A thin film manufacturing method in which a thin film is vapor-deposited on a substrate in a reaction chamber under reduced pressure,
The thin film manufacturing method characterized by including the process of decomposing | disassembling one type or multiple types of source gas used as the raw material of the said thin film by the source gas decomposition | disassembly mechanism of Claim 1, and producing | generating the decomposition | disassembly seed | species of this source gas.   13. The method according to claim 12, further comprising the step of generating a predetermined source gas decomposition species by the source gas decomposition mechanism and cleaning the surface of the substrate with the decomposition species before vapor deposition of the thin film. The thin film manufacturing method as described in any one of.   13. The thin film according to claim 12, further comprising a step of generating a decomposition source of a predetermined source gas by the source gas decomposition mechanism and etching the surface of the substrate or the surface of the thin film with the decomposition species. Production method.   A thin film laminate comprising a plurality of thin films laminated on a substrate, wherein the plurality of thin films include at least one thin film produced by the thin film production method according to claim 12. The carbon impurity concentration at the interface between the substrate and the thin film in contact with the substrate is 1 × 10 ¹⁷ cm ⁻³ or less, and the oxygen impurity concentration is 1 × 10 ¹⁷ cm ⁻³ or less. Thin film laminate.   The thin film laminate according to claim 15, wherein the substrate is an organic film.   The thin film laminate according to claim 15, wherein the thin film produced by the thin film production method according to claim 12 is a protective film that covers the organic EL element formed on the substrate.

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