JP6257437B2 - Crystal growth equipment - Google Patents

Description

  The present invention relates to a vapor phase growth apparatus capable of simultaneously growing a group III nitride crystal on a plurality of substrates by reacting a group III source gas and a nitrogen source gas.

  Group III nitride semiconductor crystals such as aluminum nitride, gallium nitride, and indium nitride have a wide range of band gap energy values, which are about 6.2 eV, about 3.4 eV, and about 0.7 eV, respectively. Degree. These group III nitride semiconductors can form mixed crystal semiconductors having an arbitrary composition, and can take values between the above band gaps depending on the mixed crystal composition.

  Therefore, by using a group III nitride semiconductor crystal, it is possible in principle to produce a wide range of light emitting elements from infrared light to ultraviolet light. In particular, in recent years, development of light-emitting elements using aluminum-based group III nitride semiconductors (mainly aluminum gallium nitride mixed crystals) has been vigorously advanced. By using an aluminum-based group III nitride semiconductor, it is possible to emit light with a short wavelength in the ultraviolet region, an ultraviolet light emitting diode for a white light source, an ultraviolet light emitting diode for sterilization, a laser that can be used for reading and writing of a high-density optical disk memory, and a laser for communication A light emitting light source such as can be manufactured.

  A light-emitting element using a group III nitride semiconductor (for example, an aluminum-based group III nitride semiconductor) is a semiconductor single crystal thin film (specifically, a thickness of about several microns on a substrate, like a conventional semiconductor light-emitting element). The thin film can be formed by sequentially stacking an n-type semiconductor layer, a light-emitting layer, and a p-type semiconductor layer. Such a thin film of a semiconductor single crystal is formed by using a crystal growth method such as a molecular beam epitaxy (MBE) method or a metalorganic chemical vapor deposition (MOCVD) method. It is possible, and it has been attempted to form a laminated structure suitable as a light emitting device by adopting such a method for a group III nitride semiconductor light emitting device.

  Currently, in the manufacture of group III nitride semiconductor light-emitting devices, a sapphire substrate is generally employed from the viewpoint of crystal quality, ultraviolet light transparency, mass productivity, and cost as a substrate. However, when a group III nitride is grown on a sapphire substrate, there is a difference in lattice constant, thermal expansion coefficient, etc. between the sapphire substrate and the group III nitride (such as aluminum gallium nitride) forming the semiconductor laminated film. As a result, crystal defects (misfit dislocations), cracks, and the like occur, causing the light emitting performance of the device to deteriorate.

  In order to solve these problems, it is desirable to use a substrate having a lattice constant close to that of the semiconductor multilayer film and a thermal expansion coefficient close to that of the semiconductor multilayer film when forming the semiconductor multilayer film. . As a substrate on which the group III nitride semiconductor thin film is formed, a group III nitride single crystal substrate is most suitable. For example, an aluminum nitride single crystal substrate or an aluminum gallium nitride single crystal substrate is optimal as a substrate on which an aluminum-based group III nitride semiconductor thin film is formed. Therefore, it is desired to develop a method capable of mass-producing a group III nitride single crystal substrate having a large area and uniform crystal quality.

  In order to use a group III nitride single crystal as a substrate, it is preferable that the single crystal has a certain thickness (for example, 10 μm or more) from the viewpoint of mechanical strength. Since the MOCVD method has a higher crystal growth rate than the MBE method, it can be said that the MOCVD method is suitable for manufacturing a group III nitride single crystal substrate. Further, a hydride vapor phase epitaxy (HVPE) method is known as a method for growing a group III nitride single crystal having a film formation rate faster than that of the MOCVD method (see Patent Documents 1 to 3). The HVPE method is not suitable for precisely controlling the film thickness as compared with the MBE method or the MOCVD method, but a single crystal with good crystallinity can be grown at a high film formation rate. It can be said that it is particularly suitable for mass production of crystal substrates. Group III nitride single crystal growth by MOCVD or HVPE is performed by supplying a group III source gas and a nitrogen source gas into a reactor and reacting both gases on a heated substrate. .

  In recent years, in order to improve mass production efficiency, it has been attempted to simultaneously grow a group III nitride single crystal on a plurality of substrates when producing a group III nitride single crystal by a vapor phase growth method. As such a multi-plate type vapor phase growth apparatus, for example, Patent Document 4 discloses that the susceptor is arranged on a disk-shaped susceptor disposed on the bottom surface portion of the flow channel and heated by a heater and rotated by driving means. A plurality of substrate holding members are rotatably provided in the circumferential direction via the rolling member, the substrate holding member is rotated with the rotation of the susceptor, and the substrate held by the substrate holding member is rotated with respect to the rotation axis of the susceptor. A vapor phase growth apparatus having a self-revolving structure that revolves while revolving is disclosed. In Patent Document 4, a gas phase raw material, for example, a mixed gas of trimethylgallium and ammonia is flowed while rotating and revolving the substrate in the vapor phase growth apparatus and heating the substrate to a predetermined temperature via a susceptor from a heater. It is described that a thin film is deposited on the surfaces of a plurality of substrates by being introduced into a channel and discharged from an exhaust port on the outer periphery.

JP 2003-303774 A JP 2006-073578 A JP 2006-114845 A JP 2007-243060 A

  However, as a result of further investigation by the present inventors, when a group III nitride single crystal is grown on a plurality of substrates using a conventionally known multiple-type vapor phase growth apparatus, an attempt is made to increase the growth rate of the crystal. As a result, it has been found that the growth film thickness and the crystal quality tend to vary among a plurality of substrates manufactured in the same flow channel. This tendency is prominent when the HVPE method with fast crystal growth is employed, and particularly, when an aluminum nitride single crystal is produced.

  The present invention relates to a vapor phase growth apparatus for simultaneously growing a group III nitride crystal on a plurality of substrates, and capable of mass-producing a group III nitride single crystal substrate having a stable quality. It is an object to provide a simple configuration. A method for producing a group III nitride using the vapor phase growth apparatus is also provided.

A first aspect of the present invention is a vapor phase growth apparatus for growing a group III nitride crystal on a substrate by reacting a group III source gas and a nitrogen source gas,
A plurality of hollow flow channels;
The assembly section;
One or more first raw material supply sections for supplying a group III raw material gas;
One or more second raw material supply parts for supplying a nitrogen source gas,
One end of each hollow flow channel is provided facing the assembly,
All of the first raw material supply units are disposed in the gathering unit,
A first heating device that heats all of the first raw material supply units with the same and common heating means;
Each hollow flow channel
A support base disposed between one end and the other end of the hollow flow channel and rotatably supporting the substrate;
A local heating device for heating the support;
A first gas supply pipe arranged so as to blow out the group III source gas from the upper side of the support table toward the upper side of the support table;
A second gas supply pipe arranged so as to blow out nitrogen source gas from the upper side of the support unit on the collecting part side toward the upper side of the support table;
Exhaust gas that is disposed between the other end portion of the hollow flow channel or the position where the support is provided and the other end portion of the hollow flow channel, and discharges the gas in the hollow flow channel. A vapor phase growth apparatus having a mouth.

  A second aspect of the present invention includes a step of simultaneously growing a group III nitride crystal on a plurality of substrates using the vapor phase growth apparatus according to the first aspect of the present invention. This is a method for producing a group nitride.

  According to the first aspect of the present invention, it is a vapor phase growth apparatus for simultaneously growing a group III nitride crystal on a plurality of substrates, and a group III nitride single crystal substrate having a stable quality can be mass-produced. A vapor phase growth apparatus can be provided with a simple configuration.

  According to the method for producing a group III nitride according to the second aspect of the present invention, a group III nitride crystal is simultaneously grown on a plurality of substrates by a vapor phase growth apparatus having a simple configuration, and stable III Group nitride single crystal substrates can be mass-produced.

It is a figure which illustrates typically the vapor phase growth apparatus 1000 concerning one embodiment of the present invention. It is a figure which illustrates typically the vapor phase growth apparatus 2000 which concerns on other embodiment of this invention. It is a figure which illustrates typically the example of arrangement | positioning of the hollow flow channel in the vapor phase growth apparatus of this invention of the form which has three hollow flow channels by a top view. It is a figure which illustrates typically the example of arrangement | positioning of the hollow flow channel in the vapor phase growth apparatus of this invention of the form which has four hollow flow channels by a top view. It is a figure which illustrates typically the vapor phase growth apparatus 3000 which concerns on other embodiment of this invention. It is a figure which illustrates typically the vapor phase growth apparatus 4000 which concerns on other embodiment of this invention. It is a figure which illustrates typically the vapor phase growth apparatus 5000 which concerns on other embodiment of this invention. It is a figure which illustrates typically the vapor phase growth apparatus 6000 which concerns on other embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawing, some symbols may be omitted. In the present specification, “A to B” for the numerical values A and B means “A or more and B or less” unless otherwise specified. In the notation, when the unit of the numerical value A is omitted, the unit attached to the numerical value B is applied as the unit of the numerical value A. In addition, the form shown below is an illustration of this invention and this invention is not limited to these forms.

<1. Vapor growth equipment>
The vapor phase growth apparatus according to the first aspect of the present invention will be described. FIG. 1 is a schematic diagram of a vapor phase growth apparatus 1000 according to an embodiment of the present invention. The vapor phase growth apparatus 1000 includes a plurality of hollow flow channels 100 and 100; a collecting unit 200; a first raw material supply unit 300 and 300 that are disposed in the collecting unit 200 and supply a group III source gas; Each of the first raw material supply units includes a first heating device 400 that heats with the same and common heating means; and second raw material supply units 500 and 500 that supply a nitrogen source gas. One end portions 100 a and 100 a of each of the hollow flow channels 100 and 100 are provided facing the assembly portion 200.

  Each hollow flow channel 100 includes an outer chamber 101; an inner chamber 102 formed inside the outer chamber 101; and between one end 100a and the other end 100b of the hollow flow channel 100. A support table (susceptor) 120 that rotatably supports the substrate 110; a local heating device 130 that heats the support table 120; and an upper side of the support table 120 from the upper side of the assembly part side 200. A first gas supply pipe 140 arranged to blow out the group III source gas toward the upper side; so as to blow out the nitrogen source gas from the upper side on the collecting part side of the support base 120 toward the upper side of the support base A second gas supply pipe 150 disposed; the other end 100 b of the hollow flow channel 100, or a support 120 in the hollow flow channel 100. Disposed between the provided position and the other end portion 100b of the hollow flow channel 100, and an exhaust port 160 for discharging the gas in the hollow flow channel 100. The support 120 is connected to the rotation drive shaft 121 in order to support the substrate 110 in a rotatable manner. The rotation drive shaft 121 transmits power from an electric motor (not shown) to the support base 120, and rotates the support base 120 at an appropriate rotation speed.

  As the local heating device 130, known heating means such as a high-frequency coil or a resistance heater can be employed. Since the inner chamber 102 has a reaction zone in which the group III source gas and the nitrogen source gas react with each other, the inner chamber 102 is composed of a heat-resistant and acid-resistant nonmetallic material such as quartz glass, alumina, sapphire, and heat-resistant glass. It is preferable that the first gas supply pipe 140 and the second gas supply pipe 150 are also made of the same material. The outer chamber 101 may be made of the same material as the inner chamber 102. However, since the outer chamber 101 is not in direct contact with the reaction zone, it can be made of a general metal material such as stainless steel.

In the conventional multi-plate type vapor phase growth apparatus, not only the substrate surface but also the group III nitride precipitates on the inner surface of the apparatus in the vicinity of the substrate, so that the III on the surface of another substrate disposed in the same flow channel. The flow of the group source gas and the nitrogen source gas is disturbed, and as a result, the growth film thickness and the crystal quality are varied among a plurality of substrates manufactured in the same flow channel. This tendency is conspicuous when the HVPE method having a high growth rate is employed, and particularly, when an aluminum nitride single crystal is produced by the HVPE method. When aluminum nitride is produced by the HVPE method, aluminum trichloride gas is preferably used as the group III source gas. The aluminum trichloride gas is a nitrogen source gas (for example, more than other group III source gases such as gallium monochloride gas). Because of its high reactivity with ammonia and the like, polycrystalline aluminum nitride is easily formed when the reaction conditions are disturbed even a little.
In the vapor phase growth apparatus 1000, since the support bases 120 and 120 are provided in the separate hollow flow channels 100 and 100, respectively, even if a group III nitride is deposited in the vicinity of one substrate 110, the other supports The flow of the group III source gas and the nitrogen source gas on the surface of the substrate 110 is not affected. On the other hand, the first raw material supply units 300 and 300 that supply the group III raw material gas are both heated by the first heating device 400 by the same and common heating means. As a result, the vapor phase growth apparatus 1000 is capable of mass-producing a group III nitride single crystal substrate having a stable quality by vapor-phase-growing a group III nitride crystal on a plurality of substrates at the same time while having a simple configuration. Is possible.

  In the vapor phase growth apparatus 1000, the exhaust ports 160 and 160 are connected to the same and common exhaust apparatus (not shown). That is, the exhaust gas from the exhaust ports 160 and 160 is guided to the same and common exhaust device. By integrating the exhaust system of each flow channel in this way, the vapor phase growth apparatus 1000 can mass-produce a group III nitride single crystal substrate with a further simplified configuration.

  In the vapor phase growth apparatus 1000, one end portions 100a and 100a of the hollow flow channels 100 and 100, that is, the end portions 100a and 100a on the side provided facing the assembly portion 200 of the hollow flow channels 100 and 100 are , Independent in the gathering unit 200. That is, one end portions 100 a and 100 a of the hollow flow channels 100 and 100 are not in communication with each other in the assembly portion 200. Thereby, for each of the hollow flow channels 100, 100, the production conditions of the group III nitride single crystal (for example, the internal pressure of the flow channel, the temperature condition of the substrate, the rotation speed of the substrate, etc.) are adjusted more precisely. Therefore, mass production of a stable group III nitride single crystal substrate becomes easier. In addition, while the inspection and maintenance of one hollow flow channel 100 is being performed, a group III nitride single crystal substrate can be manufactured using another hollow flow channel 100.

  The vapor phase growth apparatus 1000 includes the same number of first raw material supply units 300 and 300 as the hollow flow channels 100 and 100, and each one first raw material supply unit 300 to each one hollow flow channel 100. The first gas supply pipe is configured such that the group III source gas is guided and the group III source gas is guided from the two different first source supply units 300 and 300 to the two different hollow flow channels 100 and 100. 140 and 140 are arranged. As a result, the maintenance of the apparatus becomes easier, and the group III source gas supply conditions in the reaction zone can be individually controlled for each of the hollow flow channels 100, 100. It becomes easier to mass-produce group nitride single crystal substrates.

  In the vapor phase growth apparatus 1000, the second raw material supply units 500 and 500 are both disposed in the assembly unit 200. The vapor phase growth apparatus 1000 includes a second heating apparatus 700 that heats the second raw material supply units 500 and 500 with the same and common heating means. In the vapor phase growth apparatus 1000, the first heating device 400 and the second heating device 700 are the same and common devices, and thus the heating devices are referred to as “common heating devices 400/700”. Thus, it is preferable to introduce not only the group III source gas but also the nitrogen source gas into the hollow flow channel after heating. Further, from the viewpoint of simplifying the apparatus, it is preferable that the heating means for the nitrogen source gas is also made common as described above, and the heating means for the group III source gas (first heating apparatus 400) and the heating means for the nitrogen source gas. More preferably, the (second heating device 700) is shared as described above.

  The vapor phase growth apparatus 1000 includes the same number of second raw material supply units 500 and 500 as the hollow flow channels 100 and 100, and each one second raw material supply unit 500 to each one hollow flow channel 100. The second gas supply pipe 150, so that the nitrogen source gas is guided and the nitrogen source gas is guided from the two different second raw material supply units 500, 500 to the two different hollow flow channels 100, 100. 150 is arranged. As a result, the maintenance of the apparatus becomes easier, and the nitrogen source gas supply conditions in the reaction zone can be individually controlled for each of the hollow flow channels 100, 100. It becomes easier to mass-produce a nitride single crystal substrate.

  Group III metals 301 and 301 (for example, aluminum, gallium, etc.) are respectively disposed in the first raw material supply units 300 and 300 of the vapor phase growth apparatus 1000, and halogens are provided in the first raw material supply units 300 and 300. By supplying a hydrogen halide gas (for example, hydrogen chloride gas) as a halide gas, a group III metal halide gas (for example, aluminum chloride gas, gallium chloride gas, etc.) as a group III source gas is supplied to the hollow flow channels 100, 100. .) Is led. The Group III metal halide gas can be generated by the reaction of a heated Group III metal solid (301) with a hydrogen halide gas. In order to advance this reaction, the first raw material supply units 300 and 300 are heated by a first heating device 400 (common heating device 400/700) at a temperature suitable for the reaction (for example, 150 to 300 for generation of aluminum chloride gas). The temperature is about 1000 ° C., preferably about 300 to 660 ° C., more preferably about 300 to 600 ° C., and about 300 to 1000 ° C. in the generation of gallium chloride gas. This reaction is a reaction between a solid (Group III metal) and a gas (hydrogen halide gas). The contact between the two is that one (solid) does not move and only the other (hydrogen halide gas) moves. Is done. Therefore, even if the heating means for heating the first raw material supply units 300 and 300 is shared (that is, the first heating device 400), the group III metal halide gas can be stably supplied. As the nitrogen source gas to be reacted with the group III metal halide gas, a reactive gas containing nitrogen can be used, but ammonia gas can be preferably used from the viewpoint of cost and ease of handling.

  In the above description of the present invention, the vapor phase growth apparatus 1000 in which the exhaust ports 160 and 160 of the hollow flow channels 100 and 100 are connected to the same and common exhaust apparatus is illustrated. The vapor phase growth apparatus is not limited to this form. For example, a vapor phase growth apparatus in which the exhaust port of each hollow flow channel is connected to a separate exhaust apparatus may be used. However, from the viewpoint of further simplifying the device, it is preferable to use a common exhaust device that guides the exhaust from the exhaust port as described above.

In the above description regarding the present invention, the vapor phase growth apparatus 1000 in which a group III nitride crystal is grown by the HVPE method is mainly exemplified, but the present invention is not limited to this form. For example, a vapor phase growth apparatus in which a group III nitride crystal is grown by MOCVD can be used. More specifically, the first raw material supply unit may be a vapor phase growth apparatus configured to supply a group III organometallic compound gas (for example, trimethylaluminum gas or trimethylgallium gas) as a group III source gas. It is. In that case, the first raw material supply unit is configured such that the Group III metal 301 is not disposed, and instead of the halide gas, a gas obtained by separately vaporizing the Group III organometallic compound is supplied to the first raw material supply unit. After the temperature is raised to a desired temperature (for example, room temperature to 100 ° C.) by the first heating device 400 (common heating device 400/700) in the raw material supply section, the hollow flow channel is passed through the first gas supply pipe 140. The form introduced into 100 can be illustrated. Further, even when a group III nitride crystal is grown by the HVPE method, a group III halide gas separately generated in place of the halide gas without arranging the group III metal 301 in the first raw material supply unit. Is heated to a desired temperature (for example, 150 to 1000 ° C.) by the first heating device 400 (common heating device 400/700) in the first raw material supply unit. It is also possible to adopt a configuration in which the gas is introduced into the hollow flow channel 100 through the first gas supply pipe 140.
Further, for example, in the case of growing a mixed crystal by the HVPE method, a plurality of types of Group III metals are arranged in the first raw material supply unit, and a Group III halide mixed gas is generated by supplying a halide gas, and the mixing is performed. While it is possible to introduce the gas into the hollow flow channel 100 through the first gas supply pipe 140, a group III metal is not disposed in the first raw material supply unit, and instead of the halide gas, it is separately provided. The generated group III halide mixed gas is supplied to the first raw material supply unit, and the first raw material supply unit uses the first heating device 400 (common heating device 400/700) to achieve a desired temperature (for example, 150 to 1000 ° C.). Etc.) and then introduced into the hollow flow channel 100 through the first gas supply pipe 140.

  In the above description related to the present invention, the vapor phase growth apparatus 1000 in a form in which the end portions 100a, 100a on the side provided facing the assembly portion 200 of the hollow flow channels 100, 100 are independent in the assembly portion 200 is described. Although illustrated, the vapor phase growth apparatus of the present invention is not limited to this form. For example, a vapor phase growth apparatus in which one end of each hollow flow channel (the end provided on the side facing the assembly) is communicated with the assembly is also possible. FIG. 2 is a diagram schematically illustrating a vapor phase growth apparatus 2000 according to another embodiment of the present invention. In FIG. 2, the same elements as those already described in FIG. 1 are denoted by the same reference numerals as those in FIG. In the vapor phase growth apparatus 2000 of FIG. 2, the flow channel communication pipe 103 provided in the collecting portion 2200 communicates with the end portions 100 a and 100 a on the collecting portion 2200 side of the hollow flow channels 100 and 100, thereby forming a hollow shape. The flow channels 100, 100 communicate with each other in the collecting unit 2200. According to such a form, it becomes easy to equalize the internal pressure of each hollow flow channel.

  In the above description regarding the present invention, the vapor phase growth apparatus 1000 having two hollow flow channels 100, 100 extending in opposite directions is mainly exemplified, but the vapor phase growth apparatus of the present invention is limited to this form. Not. For example, a vapor phase growth apparatus having three or more hollow flow channels may be used. Even in the case where the vapor phase growth apparatus of the present invention has three or more hollow flow channels, one end of each hollow flow channel is provided as in the case of having two hollow flow channels (FIGS. 1 and 2). Portion (the end portion on the side to which the group III source gas and nitrogen source gas are supplied. For example, in FIG. 1 and FIG. 2, the end portion 100a) is provided so as to face the collecting portion. It arrange | positions so that it may extend in the direction of leaving | separating. FIG. 3 is a diagram for explaining an example of the arrangement of the hollow flow channels in the vapor phase growth apparatus of the present invention having three hollow flow channels in a top view. FIG. 4 is a view for explaining an example of the arrangement of the hollow flow channels in the vapor phase growth apparatus of the present invention having four hollow flow channels in a top view. 3 and 4, only the hollow flow channel is extracted for visibility. As illustrated in FIGS. 3 and 4, the plurality of hollow flow channels can be arranged radially in a top view. The number of hollow flow channels in the vapor phase growth apparatus of the present invention is not particularly limited as long as it is 2 or more, but is preferably 6 or less from the viewpoint of improving the maintainability of the apparatus.

The vapor phase growth apparatus 1000 having two hollow flow channels exemplified above includes the same number of first raw material supply units 300 and 300 as the hollow flow channels 100 and 100, The group III source gas is guided from the raw material supply unit 300 to each one of the hollow flow channels 100, and from the two different first raw material supply units 300, 300 to the two different hollow flow channels 100, 100 to the III. First gas supply pipes 140 and 140 are disposed so that the group source gas is guided. In the vapor phase growth apparatus of the present invention having three or more hollow flow channels, the same number of first raw material supply sections as the plurality of hollow flow channels are provided, and each first raw material supply section A group III source gas is introduced into each one hollow flow channel, and two different hollows are formed from the two different first raw material supply units for each of the two different first raw material supply units. It is preferable that the first gas supply pipe is disposed so that the group III source gas is introduced into the flow channel. According to such an embodiment, the maintenance of the apparatus becomes easier, and it becomes possible to individually control the group III source gas supply conditions in the reaction zone for each of the plurality of hollow flow channels. It becomes easier to mass-produce a group III nitride single crystal substrate of the same quality. Here, the vapor phase growth apparatus includes N (N is an integer of 2 or more) hollow flow channels F ₁ ,..., F _N and the same number (N) of first raw material supply units S ¹ ₁ ,. ¹ _N , “the group III source gas is guided from each one first source supply unit to each one hollow flow channel” means that the first source supply unit S ¹ _i (1 ≦ i ≦ N), there is a hollow flow channel F _j (1 ≦ j ≦ N) that receives the supply of the III source gas from the first source supply unit S ¹ _i , and the first source supply unit S ^{If the} group III source gas is led from ¹ _i to the hollow flow channel F _j (1 ≦ j ≦ N), the other hollow flow channel F _k (1 ≦ k ≦ N, k ≠ j) is the same first Means that no Group III source gas is supplied from the source supply part S ¹ _i . The hollow flow channels _F 1 of the vapor phase growth apparatus is N (N is an integer of 2 or more), ..., _{F N,} and the same number first raw material supply section ^S ₁ 1 (N pieces), ^{..., S} _{1 N} , "Group III source gas is led from two different first raw material supply units to two different hollow flow channels in any of a pair of two different first raw material supply units." Is a hollow shape in which a group III source gas is guided from S ¹ _i for any combination of two different first raw material supply sections S ¹ _i , S ¹ _j (1 ≦ i, j ≦ N, i ≠ j) The flow channel F _p (1 ≦ p ≦ N) is different from the hollow flow channel F _q (1 ≦ q ≦ N) from which the group III source gas is led from S ¹ _j (that is, p ≠ q). Means that.

Further, the vapor phase growth apparatus 1000 having two hollow flow channels exemplified above includes the same number of second raw material supply units 500, 500 as the hollow flow channels 100, 100, and each second Nitrogen source gas is introduced from each raw material supply section 500 to each one of the hollow flow channels 100, and nitrogen is supplied to two different hollow flow channels 100, 100 from two different second raw material supply sections 500, 500. Second gas supply pipes 150 and 150 are arranged so that the source gas is guided. In the vapor phase growth apparatus of the present invention having three or more hollow flow channels, the same number of second raw material supply units as a plurality of hollow flow channels are provided, Nitrogen source gas is guided to each one of the hollow flow channels, and two different hollow shapes from the two different second raw material supply sections are set for any of the two different sets of the second raw material supply sections. It is preferable that the second gas supply pipe is disposed so that the nitrogen source gas is guided to the flow channel. According to such an embodiment, the maintenance of the apparatus becomes easier, and the nitrogen source gas supply conditions in the reaction zone can be individually controlled for each of the hollow flow channels. It becomes easier to mass-produce the group III nitride single crystal substrate. Here, the vapor phase growth apparatus has N (N is an integer of 2 or more) hollow flow channels F ₁ ,..., F _N and the same number (N) of second raw material supply units S ² ₁ ,. ² _N , “the nitrogen source gas is led from each one second raw material supply unit to each one hollow flow channel” means that the second raw material supply unit S ² _i (1 ≦ i ≦ N ), There is a hollow flow channel F _j (1 ≦ j ≦ N) that receives supply of the nitrogen source gas from the second raw material supply unit S ² _i , and the second raw material unit S ² _i If the nitrogen source gas is led to the hollow flow channel F _j (1 ≦ j ≦ N), the other hollow flow channel F _k (1 ≦ k ≦ N, k ≠ j) is supplied with the same second raw material. This means that no nitrogen source gas is supplied from the part S ² _i . The hollow flow channels _F 1 of the vapor phase growth apparatus is N (N is an integer of 2 or more), ..., _{F N} and equal second raw material supply section ^S ₂ 1 of the (N pieces), ^{..., S} _{2 N} "For any set of two different second raw material supply units, the nitrogen source gas is led from the two different second raw material supply units to two different hollow flow channels" A hollow flow channel in which nitrogen source gas is guided from S ² _i for any combination of two different first raw material supply sections S ² _i , S ² _j (1 ≦ i, j ≦ N, i ≠ j) This means that F _p (1 ≦ p ≦ N) is different from the hollow flow channel F _q (1 ≦ q ≦ N) through which the nitrogen source gas is led from S ² _j (that is, p ≠ q). To do.

  In the above description regarding the present invention, the same number of first raw material supply units 300, 300 as the hollow flow channels 100, 100 are provided, and each one first raw material supply unit 300 is connected to each one hollow flow channel 100. The first gas supply pipe is configured such that the group III source gas is guided and the group III source gas is guided from the two different first source supply units 300 and 300 to the two different hollow flow channels 100 and 100. Although the vapor phase growth apparatus 1000 of the aspect in which 140 and 140 are disposed is mainly exemplified, the vapor phase growth apparatus of the present invention is not limited to this form. A vapor phase growth apparatus in which a first gas supply pipe is disposed so that a group III source gas is guided from a single first source supply section to any of a plurality of hollow flow channels; It is also possible to do. FIG. 5 is a diagram schematically illustrating a vapor phase growth apparatus 3000 according to another embodiment of the present invention. In FIG. 5, the same elements as those already shown in FIGS. The vapor phase growth apparatus 3000 has two hollow flow channels 100 and 100, while having a single first raw material supply unit 3300. The first gas supply pipes 3140 and 3140 are arranged so that the group III source gas is guided from the single first raw material supply unit 3300 to both the hollow flow channels 100 and 100. In the vapor phase growth apparatus 3000, the group III source gas flowing out from the single first source supply unit 3300 is branched at the collecting unit 3200, and the hollow flow channel 100 is connected via the first gas supply pipes 3140 and 3140. , 100. According to such a form, it is possible to simplify the means for supplying the group III source gas.

  In the above description regarding the present invention, the second raw material supply units 500 and 500 are all disposed in the assembly unit 200, and both of the second raw material supply units 500 and 500 are heated by the same and common heating means. Although mainly exemplified is the vapor phase growth apparatus 1000 having the second heating apparatus 700, and the first heating apparatus 400 and the second heating apparatus 700 are the same common heating apparatus 400/700. The present invention is not limited to this form. The first heating device for heating the first raw material supply unit for supplying the group III source gas and the second heating device for heating the second raw material supply unit for supplying the nitrogen source gas are separate devices. It is also possible to form a vapor phase growth apparatus of a form, and it is also possible to make a vapor phase growth apparatus of a form having a second heating device that heats a plurality of second raw material supply parts by separate heating means It is. FIG. 6 is a diagram schematically illustrating a vapor phase growth apparatus 4000 according to another embodiment of the present invention. In FIG. 6, the same elements as those already shown in FIGS. The vapor phase growth apparatus 4000 is a first heating apparatus 4400 in which both of the first raw material supply units 300 and 300 that supply the group III source gas disposed in the collecting unit 4200 are heated by the same and common heating means. And a second heating device 4700 for heating the second raw material supply units 4500 and 4500 arranged in the collecting unit 4200 with separate heating means. In the vapor phase growth apparatus 4000, the first heating apparatus 4400 and the second heating apparatus 4700 are separate heating apparatuses that are not shared.

  In addition, the vapor phase growth apparatus 4000 shown in FIG. 6 has the same number of first raw material supply units 300 and 300 as the hollow flow channels 100 and 100, and each of the first raw material supply units 300 has one each. The group III source gas is guided to the hollow flow channel 100 of FIG. 5 and the group III source gas is guided to the two different hollow flow channels 100, 100 from the two different first source supply units 300, 300. Although the first gas supply pipes 140 and 140 are disposed, the vapor phase growth apparatus of the present invention is not limited to such a configuration as described above. A vapor phase growth apparatus in which a first gas supply pipe is arranged so that a group III source gas is guided from a single first source supply section to any of a plurality of hollow flow channels. FIG. 7 is a diagram schematically illustrating a vapor phase growth apparatus 5000 according to another embodiment of the present invention. In FIG. 7, the same elements as those already shown in FIGS. The vapor phase growth apparatus 5000 has two hollow flow channels 100 and 100, while having a single first raw material supply unit 5300. The first gas supply pipes 5140 and 5140 are arranged so that the group III source gas is guided from the single first source supply unit 5300 to both of the hollow flow channels 100 and 100. In the vapor phase growth apparatus 5000, the group III source gas flowing out from the single first source supply unit 5300 is branched at the collecting unit 5200, and the hollow flow channel 100 is connected via the first gas supply pipes 5140 and 5140. , 100. The vapor phase growth apparatus 5000 heats a single first raw material supply unit 5300 disposed in the collecting unit 5200, and a second raw material disposed in the collecting unit 5200. It has the 2nd heating apparatus 5700 which heats the supply parts 5500 and 5500 with a separate heating means, respectively. In the vapor phase growth apparatus 5000, the first heating apparatus 5400 and the second heating apparatus 5700 are separate heating apparatuses that are not shared.

  In the above description of the present invention, the same number of second raw material supply units 500, 500 as the hollow flow channels 100, 100 are provided, and each one second raw material supply unit 500 is connected to each one hollow flow channel 100. The second gas supply pipe 150, so that the nitrogen source gas is guided and the nitrogen source gas is guided from the two different second raw material supply units 500, 500 to the two different hollow flow channels 100, 100. Although the vapor deposition apparatus 1000 in the form in which 150 is disposed is mainly exemplified, the vapor deposition apparatus of the present invention is not limited to this form. For example, the vapor phase growth apparatus in which the second gas supply pipe is arranged so that the nitrogen source gas is guided from the single second raw material supply unit to any of the plurality of hollow flow channels. It is also possible. FIG. 8 is a diagram schematically illustrating a vapor phase growth apparatus 6000 according to another embodiment of the present invention. In FIG. 8, the same elements as those already shown in FIGS. The vapor phase growth apparatus 6000 has two hollow flow channels 100 and 100, while having a single second raw material supply unit 6500. The second gas supply pipes 6150 and 6150 are arranged so that the nitrogen source gas is guided from the single second raw material supply unit 6500 to both of the hollow flow channels 100 and 100. In the vapor phase growth apparatus 5000, the nitrogen source gas flowing out from the single second raw material supply unit 6500 is branched at the collecting unit 6200, and the hollow flow channel 100, via the second gas supply pipes 6150 and 6150, 100 leads to both.

Although not shown in FIGS. 1 to 8, the vapor phase growth apparatus of the present invention may have the following constituent members. For example, in each hollow flow channel 100, a barrier gas is interposed between the flow of the group III source gas flowing out from the first gas supply pipe 140 and the flow of the nitrogen source gas flowing out from the second gas supply pipe 150. You may have the structure to supply. As the barrier gas, for example, a general gas such as hydrogen, nitrogen, argon, or helium can be used.
Further, the group III source gas and the nitrogen source gas are circulated in each hollow flow channel 100 so that the group III source gas and the nitrogen source gas uniformly flow without flowing back in each hollow flow channel 100 to the side where the exhaust port 160 is provided. You may have the structure which supplies extrusion gas toward the side in which the exhaust port 160 was provided from the nozzle side of the 1st gas supply pipe | tube 140 and the 2nd gas supply pipe | tube 150. FIG. The position where the extrusion gas is supplied in the hollow flow channel can be a position outside the flow of the nitrogen source gas, the group III source gas, and the barrier gas. As the extrusion gas, for example, a general gas such as hydrogen, nitrogen, argon, or helium can be used.
In addition, the crystal growth apparatus of the present invention may be provided with an auxiliary heating device so as to heat the pipes provided in the gathering portions (200, 2200, 3200, 4200, 5200, 6200). By providing such an auxiliary heating device, it is possible to prevent the source gas flowing through the collecting portion from being precipitated in the pipe (for example, the first gas supply pipes 140, 3140, 5140, etc.) due to a temperature drop. Is possible. As the auxiliary heating device, known heating means such as a resistance heating device, a light heating device, and a high-frequency heating device can be used.

<2. Method for Producing Group III Nitride>
A method for producing a group III nitride according to the second aspect of the present invention will be described. The method for producing a group III nitride of the present invention is characterized in that group III nitride crystals are vapor-phase grown simultaneously on a plurality of substrates using the crystal growth apparatus according to the first aspect of the present invention.

  Group III source gas supplied from the first source supply unit 300 in the vapor phase growth apparatus 1000 (FIG. 1) includes aluminum halides such as aluminum trichloride and aluminum tribromide; gallium trichloride, gallium monochloride and the like. Gallium halides: Group III halide gases such as indium halides such as indium trichloride, and group III organometallic compound gases such as trimethylaluminum and trimethylgallium can be used without particular limitation. When producing a mixed crystal, a mixed gas containing a plurality of group III source gases is used. When employing the HVPE method, as described above, the group III metal 301 is disposed in the first raw material supply unit 300, and the first raw material supply unit 300 is moved by the first heating device 400 (common heating device 400/700). Heating (for example, when generating aluminum trichloride gas, it is about 150-1000 ° C., preferably about 300-660 ° C., more preferably about 300-600 ° C., when generating gallium monochloride gas. The group III halide gas generated in the first raw material supply unit 300 is supplied to the first raw material supply unit 300 by supplying a halide gas (for example, hydrogen chloride gas) to the first raw material supply unit 300. And can be introduced into the hollow flow channel 100 through the first gas supply pipe 140. On the other hand, the group III metal 301 is not disposed in the first source supply unit 300, but a group III source gas separately generated instead of the halide gas (in the case of the HVPE method, the group III halide gas, in the case of the MOCVD method) Is supplied to the first raw material supply unit, and the first raw material supply unit uses the first heating device 400 (common heating device 400/700) to obtain a desired temperature (for example, room temperature to 100). It is also possible to adopt a mode in which the temperature is raised to 0 ° C.) and then introduced into the hollow flow channel 100 through the first gas supply pipe 140. These group III source gases are usually supplied in a state diluted with a carrier gas. As the carrier gas, hydrogen gas, nitrogen gas, helium gas, argon gas, or a mixed gas thereof can be used without particular limitation, and a carrier gas containing hydrogen gas is preferably used.

  In general, when a group III halide gas is used as a group III source gas, that is, when a group III nitride is grown by the HVPE method having a high film formation rate, the conventional multi-plate vapor phase growth apparatus uses the same flow channel. The film thickness and crystallinity are likely to vary among a plurality of the substrates, and this tendency is particularly noticeable when an aluminum halide gas having a high reaction rate is used. The Group III nitride production method can be preferably used when a Group III nitride is grown by the HVPE method. The Group III nitride containing aluminum as a Group III element by the HVPE method (hereinafter referred to as “Al-based Group III nitride”). )) Is preferably used for growing a single crystal, and nitride nitride is formed by the HVPE method. It can be most preferably used when growing a single crystal of Miniumu. From this viewpoint, in the Group III nitride production method of the present invention, the Group III source gas preferably contains an aluminum halide gas, and the Group III source gas is particularly preferably an aluminum halide gas.

  Between the flow of the group III source gas flowing out from the first gas supply pipe 140 in each hollow flow channel 100 of the vapor phase growth apparatus 1000 and the flow of the nitrogen source gas flowing out from the second gas supply pipe 150. May intervene a flow of barrier gas. The barrier gas that flows between the flow of the group III source gas and the flow of the nitrogen source gas is inactive, and the diffusion of the group III source gas or the nitrogen source gas into the barrier gas is slow due to the large molecular weight. In terms of (high barrier effect), nitrogen gas, argon gas, or a mixed gas thereof can be preferably used. However, in order to adjust the effect of the barrier gas, nitrogen gas or argon gas or a mixed gas thereof is inert such as hydrogen gas, helium gas, neon gas (that is, does not react with group III source gas and nitrogen source gas). A low molecular weight gas may be mixed.

  Examples of the material of the substrate 110 on which the group III nitride single crystal is deposited include, for example, sapphire, silicon, silicon carbide, zinc oxide, gallium nitride, aluminum nitride, aluminum gallium nitride, gallium arsenide, zirconium boride, and titanium boride. Can be used without restriction.

  In order to obtain a group III nitride single crystal by nitriding the group III source gas introduced into the hollow flow channel 100 from the first source supply unit 300 via the first gas supply pipe 140, the second source material Nitrogen source gas is introduced into the hollow flow channel 100 from the supply unit 500 via the second gas supply pipe 150. This nitrogen source gas is usually supplied in a state diluted with a carrier gas. As the nitrogen source gas, a reactive gas containing nitrogen can be used without particular limitation, but ammonia gas can be preferably used from the viewpoint of cost and ease of handling. As the carrier gas, hydrogen gas, nitrogen gas, helium gas, argon gas, or a mixed gas thereof can be used without particular limitation, and a carrier gas containing hydrogen gas is preferably used.

  Before the reaction between the group III source gas and the nitrogen source gas, in order to remove organic substances adhering to the substrate 110, the carrier gas containing hydrogen gas is circulated through the hollow flow channel 100 through the support 120. Thermal cleaning is preferably performed by heating the substrate 110. When using a sapphire substrate as the substrate 110, it is generally held at 1100 ° C. for about 10 minutes. Thereafter, the group III source gas was introduced into the hollow flow channel 100 through the first gas supply pipe 140 and heated while introducing the nitrogen source gas into the hollow flow channel 100 through the second gas supply pipe 150 ( A group III nitride single crystal is grown on the substrate 110. The HVPE method is preferably 1000 to 1700 ° C. and the MOCVD method is preferably 1000 to 1600 ° C. The growth of the group III nitride in the method for producing a group III nitride of the present invention is usually performed under a pressure around atmospheric pressure when the HVPE method is used (that is, when a group III halide gas is used as the group III source gas). When the MOCVD method is used (that is, when a group III organometallic compound gas is used as the group III source gas), it is usually performed under a pressure of 100 Pa to atmospheric pressure.

  When the HVPE method is used, the supply amount of the group III source gas (group III halide gas) is the supply partial pressure (total gas to be supplied (carrier gas, group III source gas, nitrogen source gas, barrier gas, extrusion gas). The ratio of the volume of the group III source gas in the standard state to the total volume in the standard state. When the MOCVD method is used, the supply amount of the group III source gas (group III organometallic compound gas) is usually selected in the range of 0.1 to 100 Pa in terms of supply partial pressure. The supply amount of the nitrogen source gas is not particularly limited, but generally, a supply amount of 0.5 to 500 times that of the group III source gas to be supplied is preferably employed.

  The growth time is appropriately adjusted so that a desired growth film thickness is achieved. After crystal growth for a certain time, the crystal growth is terminated by stopping the supply of the group III source gas. Thereafter, the temperature of the substrate 110 is lowered to room temperature. Through the above operation, a group III nitride single crystal can be grown on the substrate 110.

  The vapor phase growth apparatus and the Group III nitride manufacturing method of the present invention can be preferably used when a Group III nitride crystal having a thickness of 10 μm or more is grown on a substrate, and the Group III nitride having a thickness of 100 μm or more on the substrate. It can be particularly preferably used when growing a physical crystal.

  In the above description regarding the present invention, the method for producing a group III nitride using the vapor phase growth apparatus 1000 illustrated in FIG. 1 is mainly exemplified, but the method for producing a group III nitride according to the present invention is limited to this form. Not. As described above for the vapor phase growth apparatus of the present invention, a vapor phase growth apparatus having three or more hollow flow channels (see FIGS. 2 and 3); an exhaust apparatus in which exhaust from a plurality of hollow flow channels is separate A vapor phase growth apparatus in a form guided by the vapor phase growth apparatus; a vapor phase growth apparatus in a form in which ends of the hollow flow channel on the collection part side communicate with each other in the collection part (see FIG. 4); a single first raw material supply part A vapor phase growth apparatus (see FIGS. 5 and 7) in which the first gas supply pipe is disposed so that the group III source gas is introduced to any of the plurality of hollow flow channels from the first to second ends; A vapor phase growth apparatus (see FIGS. 6 and 7) in which the apparatus heats a plurality of second raw material portions with separate heating means, or the first heating apparatus and the second heating apparatus are separate apparatuses. Alternatively, a plurality of hollow flows from a single second raw material supply unit A group III nitride is simultaneously formed on a plurality of substrates by using a vapor phase growth apparatus (see FIG. 8) in which a second gas supply pipe is arranged so that a nitrogen source gas is guided to any of the channels. It is also possible to employ a method for producing a group III nitride having a step of growing crystals.

1000, 2000, 3000, 4000, 5000 Vapor phase growth apparatus 100 Hollow flow channel 100a One end of hollow flow channel 100 (end on the assembly side)
100b The other end part 200, 2200, 3200, 4200, 5200, 6200 of the hollow flow channel 100 1st collecting part 300, 3300, 5300 1st raw material supply part 301 Group III metal 400, 4400, 5400 1st heating apparatus 500 4500, 5500, 6500 Second raw material supply unit 700, 4700, 5700 Second heating device 400/700 Common heating device 101 Outer chamber 102 Inner chamber 103 Flow channel communication tube 110 Substrate 120 Support base (susceptor)
121 Rotation drive shaft 130 Local heating device 140, 3140, 5140 First gas supply pipe 150, 6150 Second gas supply pipe 160 Exhaust port

Claims (11)

A vapor phase growth apparatus for growing a group III nitride crystal on a substrate by reacting a group III source gas and a nitrogen source gas,
A plurality of hollow flow channels;
The assembly section;
One or more first raw material supply parts arranged in the collecting part for supplying a group III raw material gas;
A first heating device that heats all of the one or more first raw material supply units with the same and common heating means;
One or more second raw material supply sections for supplying a nitrogen source gas;
Have
One end of each of the hollow flow channels is provided facing the assembly part,
Each said hollow flow channel is
A support base rotatably disposed between the one end and the other end of the hollow flow channel;
A local heating device for heating the support;
A first gas supply pipe arranged to blow out the group III source gas from the upper side of the support table toward the upper side of the support table;
A second gas supply pipe arranged to blow out the nitrogen source gas from the upper side of the support table on the side of the collecting portion toward the upper side of the support table;
Disposed between the other end of the hollow flow channel or between the position where the support is provided and the other end of the hollow flow channel, and discharges the gas in the hollow flow channel With exhaust vent
Have
The one or more second raw material supply units are all disposed in the assembly unit,
A vapor phase growth apparatus characterized by having a second heating device in which all of the second raw material supply sections are heated by the same and common heating means.   2. The vapor phase growth apparatus according to claim 1, wherein each of the exhaust ports is connected to the same and common exhaust apparatus.   3. The vapor phase growth apparatus according to claim 1, wherein one end of each of the hollow flow channels is independent at the gathering portion. 4. Having the same number of the first raw material supply sections as the plurality of hollow flow channels,
The group III source gas is guided from each one first source supply unit to each one hollow flow channel, and the two different firsts are set for any of the two different sets of first source supply units. The first gas supply pipe is arranged so that the group III source gas is led to two different hollow flow channels from the raw material supply section of any one of claims 1 to 3 The vapor phase growth apparatus described in 1.   The first gas supply pipe is arranged so that a group III source gas is led from any single first raw material supply section to any of the plurality of hollow flow channels. The vapor phase growth apparatus according to any one of claims 1 to 3. Characterized in that said first heating device and the second heating apparatus are identical and common equipment, chemical vapor deposition apparatus according to any one of claims 1 to 5. Having the same number of second raw material supply sections as the plurality of hollow flow channels,
Nitrogen source gas is led from each one second raw material supply section to each one hollow flow channel, and each of the two different second raw material supply sections has the two different second The said 2nd gas supply pipe | tube is arrange | positioned so that nitrogen source gas may be guide | induced to two different hollow flow channels from a raw material supply part, The any one of Claims 1-6 characterized by the above-mentioned. Vapor growth equipment. The second gas supply pipe is disposed so that a nitrogen source gas is guided from a single second raw material supply unit to any of the plurality of hollow flow channels. The vapor phase growth apparatus according to any one of claims 1 to 6 . Aluminum is disposed in the first raw material supply unit,
By supplying hydrogen chloride gas to the raw material supply section of the first, characterized in that the aluminum chloride gas as a group III material gas is led to the plurality of hollow flow channel, claim 1-8 The vapor phase growth apparatus described in 1. Growing thickness 10μm or more crystalline, vapor phase growth apparatus according to any one of claims 1-9. Method of manufacturing according to claim 1 by a vapor deposition apparatus according to any one of 10, characterized by having a step of growing at the same time the Group III nitride crystal on a plurality of substrates, the group III nitride.

Images