JP3534940B2 - Thin film vapor deposition equipment - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin film vapor phase epitaxy apparatus, and more particularly to a thin film vapor phase epitaxy apparatus suitable for vapor phase growing a high dielectric constant thin film such as barium titanate / strontium titanate.

[0002]

2. Description of the Related Art In recent years, the degree of integration of integrated circuits in the semiconductor industry has been remarkably improved, and research and development has been conducted on DRAMs that are focused on the gigabit order from the present megabit order to the future. In such a DRAM, a capacitance element is indispensable, but it is preferable that a capacitance as large as possible be obtained with a small area. Therefore, as the dielectric thin film, a silicon oxide film, a silicon nitride film, or the like is currently used, but these have a dielectric constant of 10 or less, and tantalum pentoxide having a dielectric constant of about 20 in the future ( ta ₂ O ₅₎ film or barium titanate dielectric constant of about 300 (BaTiO _3,), strontium titanate (SrTiO ₃₎ or a metal oxide thin film material such as barium titanate strontium promising mixtures thereof Has been done.

An example of vapor phase growth apparatus for these metal oxide thin films is disclosed in Japanese Patent Laid-Open No. 63-307276. This is a vapor phase growth apparatus for metal oxides that introduces multiple kinds of organometallic compound gas into a reaction tube and deposits the metal compound generated by the vapor phase reaction on a substrate held in a heated state in the reaction tube. Is. And this device is a heating device for heating the wall surface of the gas supply system of the organometallic compound, a heating device for the reaction tube, a supply device for the oxygen-containing gas, and the oxygen-containing gas from the supply device is introduced into the reaction tube, An oxygen-containing gas guide tube that approaches the substrate and discharges the oxygen-containing gas, and a guide tube that guides the gas from the organometallic compound gas supply system into the reaction tube are provided.

In general, the organometallic compound gas is very unstable in oxygen, so that when oxygen is introduced into the reaction system, an explosion or an early reaction on the outside of the substrate is likely to occur. For this reason,
The metal oxide thin film can be grown on the substrate by separately guiding the organometallic compound gas introduction pipe and the oxygen gas introduction pipe to the vicinity of the substrate and achieving rapid uniform mixing. At this time, since the organometallic compound gas is a liquid at room temperature,
In order to prevent this from condensing, it is necessary to heat the gas introduction pipe up to the reaction part and the entire reaction part, and a heating device for heating the wall surface of the gas supply system as described above,
And a heating device for the reaction tube. Further, the susceptor on which the substrate is placed is equipped with a heating device because it is necessary to maintain the temperature at an appropriate temperature for the vapor phase growth reaction.

Further, in Japanese Patent Laid-Open No. 5-335248, a substrate heating heater for placing and heating a semiconductor substrate is arranged in a container in order to perform vapor phase growth on the semiconductor substrate.
Further, there is disclosed a thin film vapor phase growth apparatus provided with a heater for heating an inner wall of a gas introduction hole for introducing a vapor phase growth source gas into a reaction container so that the source gas is not condensed.

Further, Japanese Patent Application Laid-Open No. 4-364024 discloses a vapor phase growth method using an organometallic compound as a raw material gas. This vapor phase growth method uses an organic metal gas as a raw material, and its purpose is to produce an epitaxial growth layer having a uniform thickness with good reproducibility. The metal-organic raw material gas being vapor-phase-grown goes around the outer periphery of the baffle plate arranged in parallel with the substrate to be vapor-phase-grown, and is radially sent inward along the injection board having the slot. The slots of the injection board spread out radially, their width is not uniform, and the heated substrate is rotating, and by sending the above-mentioned gas flow on it, it is possible to compensate for the non-uniformity of the deposition rate. There is. As a result of such vapor phase growth, an epitaxial growth layer having a uniform thickness can be obtained with good reproducibility.

[0007]

However, in vapor phase growth of a metal oxide thin film such as barium titanate,
A completely different set temperature is required for the reaction container and the substrate. For example, in the reaction vessel, a temperature accuracy of about ± 2% is required at the lower limit temperature of 250 to 260 ° C., which is the lower limit temperature at which the thin film raw material does not condense, and the upper limit temperature at which the thin film raw material remains in the vapor phase state without decomposition. The film substrate is required to have a temperature accuracy of about ± 1% at 400 to 700 ° C. In the device disclosed in the above-mentioned publication, it is difficult to control both temperatures independently. Further, since the electric furnace or the ribbon heater for high temperature is used for the heating device of the reaction tube, it is difficult to maintain the temperature of the inner wall of the reaction chamber such as the gas introduction part by the radiant heat received from the substrate heating device. Therefore, although precise temperature control is required for the substrate and the reaction vessel,
There was a problem that precise temperature control was difficult.

Particularly, in a shower head for discharging a raw material gas for growing a thin film on a substrate, it is necessary to discharge a high-temperature and uniform-temperature gas flow controlled at a constant temperature with a uniform density over the entire shower head. In the device disclosed in the above-mentioned publication, it is difficult to control both temperatures independently. Further, it is difficult to discharge a high-temperature, uniform-temperature gas flow with a uniform density over the entire shower head.
For example, in the apparatus disclosed in Japanese Patent Laid-Open No. 4-364024, the susceptor portion is heated from the outside of the reaction vessel by the high frequency coil, and the radiant heat heats the gas introduction manifold such as the injection plate. Further, since the gas flow is discharged from the slot having a non-uniform width, it is difficult to supply a high-temperature and uniform-temperature gas flow to the substrate to be vapor-phase grown as a gas flow having a uniform density.

The present invention has been made in view of the above-mentioned circumstances, and a thin film capable of maintaining the substrate at a predetermined temperature during vapor phase growth and precisely controlling the temperature of each portion surrounding the reaction chamber. An object is to provide a vapor phase growth apparatus.

[0010]

A first aspect of a thin film vapor phase growth apparatus of the present invention is provided with a stage on which a substrate is mounted, and a position facing the stage, for growing a thin film on the substrate. What is claimed is: 1. A thin film vapor deposition apparatus comprising: a shower head that discharges a source gas onto the substrate; and a reaction container that forms a reaction chamber .
Facing the first planar member facing the supply side of the raw material gas
A hollow heat medium circulation space is formed between the second planar member and the second planar member.
And penetrates both members into the circulation space of the heat medium.
A plurality of nozzle tubes having nozzle holes for
A rib disposed between the planar member and the second planar member
The ribs make a zigzag pattern on the entire surface of the shower head.
The heat medium circulation path is formed .

The second aspect of the present invention is to provide the rib as described above.
Before penetrating the first planar member and the second planar member.
The nozzle holes are provided.

[0012] A third aspect of the present invention is the shower.
-The circulation path of the heat medium of the head is composed of multiple paths,
Two circulation paths of the heat medium are arranged in parallel and close to each other.
In the portions arranged in parallel with each other.
Arranged so that the flow directions of the fluids are opposite.
It is characterized by being done .

Further, a fourth aspect of the present invention is based on the above-mentioned plurality of
The heat medium of the same temperature is supplied as the heat medium flowing in the path.
Characterized in that it is.

Further, a fifth aspect of the present invention is the above heat medium.
As a non-flammable, fluorine-based liquid flow with good thermal conductivity
Use the body to heat the nozzle tube of the showerhead at a uniform temperature.
It is characterized by heating to .

Further, a sixth aspect of the present invention is characterized in that the flow path is defined by a rib projecting from an inner wall side formed between an inner wall and an outer wall of the reaction vessel. .

Further, in a seventh aspect of the present invention, at least one system is provided for each of the shower head and the reaction vessel as the flow path of the temperature control means configured to allow the heat medium to flow therethrough. Is characterized by.

An eighth aspect of the present invention is characterized in that the shower head is provided with at least one channel for each of the vertical cylinder portion and the nozzle portion.

In a ninth aspect of the present invention, in the reaction vessel, there are a pot-shaped portion connected to the shower head and a support base portion provided near the stage and spaced from the stage. It is characterized by having at least one channel.

Further, a tenth aspect of the present invention is characterized in that a shield plate is arranged between the stage and a support base portion of the reaction container which is provided in the vicinity of and separated from the stage. And

The eleventh aspect of the present invention is characterized in that a fluorine-based liquid fluid is used as the heat medium.

A twelfth aspect of the present invention is characterized in that the thin film is a metal oxide thin film and the source gas is an organometallic source gas and an oxygen-containing gas.

A thirteenth aspect of the present invention is a vapor phase growth method of forming a thin film on a substrate by discharging a source gas onto a substrate heated in the reaction chamber, and a shower surrounding the reaction chamber. At least one of the plurality of temperature control means provided in the portion composed of the head and the reaction container is configured to allow the heat medium to flow, and the flow rate and / or temperature of the heat medium flowing in the flow path is adjusted. By
It is characterized by growing a thin film while precisely controlling the temperature of each part of the inner wall of the part surrounding the reaction chamber.

Further, a fourteenth aspect of the present invention is to provide a stage on which a substrate is mounted and a shower head which is provided at a position facing the stage and discharges a source gas for growing a thin film on the substrate onto the substrate. And a reaction vessel forming a reaction chamber, wherein the shower head has a first planar member facing the substrate and a second planar member facing the source gas supply side. A hollow heat medium circulation space is formed between the member and the planar member, and a large number of nozzle tubes having nozzle holes penetrating the both members are provided in the heat medium circulation space.

Further, in a fifteenth aspect of the present invention, the shower head includes a rib arranged between the first planar member and the second planar member, and the heat medium is circulated by the rib. It is characterized in that a route is formed.

Further, in a sixteenth aspect of the present invention, the nozzle tube is cylindrical or prismatic in shape, and an outer peripheral portion of the nozzle tube is exposed to a circulation space of the heat medium and comes into contact with the heat medium. Is characterized in that.

The seventeenth aspect of the present invention is characterized in that the heat medium circulation path is constituted by a plurality of paths.

Further, in an eighteenth aspect of the present invention, the circulation path of the heat medium has a portion in which two systems are arranged in parallel and adjacent to each other, and the fluid in the portions arranged in substantially parallel is It is characterized in that they are arranged so that the flow directions are opposite to each other.

In a nineteenth aspect of the present invention, the nozzle tube is at least a first planar member facing the substrate of the shower head or a second planar member facing the source gas supply side. It is characterized by being integrally formed with one side.

According to a twentieth aspect of the present invention, the shower head includes a first planar member facing the substrate.
Between the second planar member facing the source gas supply side,
It is characterized in that a rib forming a heat medium circulation system path is provided, and a large number of nozzle holes penetrating both the members are arranged in the rib.

Further, in a twenty-first aspect of the present invention, the shower head is fitted on one outer surface of the rib and one planar member formed in a tooth shape of a comb in which the plurality of nozzle holes are arranged. A fitting ring member having a recess on the inner periphery thereof, the space between the ribs serving as a circulation path for the heat medium, and the other planar member having an opening engaged with the nozzle hole of the rib. Is characterized by.

A twenty-second aspect of the present invention is a vapor phase growth method for forming a thin film on a substrate by discharging a source gas onto the substrate heated in a reaction chamber, at a position facing the substrate. A shower head having a large number of nozzles for discharging the raw material gas is arranged in the shower head, and a heated heating medium is circulated in the shower head, and the nozzles are heated by the heating medium to achieve constant temperature and soaking. A thin film is formed on the substrate while the heated source gas is discharged from the nozzle at a uniform density.

According to a preferred embodiment of the present invention, a plurality of temperature control means are provided in the portion constituted by the shower head and the reaction vessel, and at least one of the temperature control means is arranged so that the heat medium flows. Therefore, the temperature of each part of the inner wall of the part surrounding the reaction chamber can be arbitrarily adjusted. For this reason, the substrate grown in vapor phase is controlled at 550 ° C. by a heater built in the stage, and when the stage is configured to be able to move up and down, the temperature of each part of the reaction chamber is raised by raising and lowering the stage. Although it varies, the temperature of each part of the inner wall of the part surrounding the reaction chamber can be adjusted, so that the temperature of each part of the reaction chamber can be maintained at a constant temperature with high control accuracy of, for example, about 250 ° C ± 2%. it can.
In particular, the shower head is directly affected by the heat of the heater that heats the substrate as the stage moves up and down, but the temperature of the shower head can be kept constant by providing the temperature control means in the shower head. It is possible to prevent problems such as condensation and adhesion of gas or adhesion of reaction products, and it is possible to grow a good-quality vapor phase growth thin film.

According to a preferred aspect of the present invention, the amount of heat supplied by the heat medium is adjusted by adjusting the flow rate and / or temperature of the heat medium according to the difference between the inner wall temperature of the reaction vessel detected by the detection means and the target temperature. Can be controlled. Therefore, the temperature of the inner wall of the reaction chamber can be maintained at the set temperature.

According to a preferred embodiment of the present invention, at least one system of the temperature control means configured so that the heat medium flows is provided in the middle of the flow path so that the temperature of the heat medium is lower than that of the other systems. Since the cooling means is provided, the heating medium having a low temperature can be supplied to the shower head even when the high temperature stage approaches the shower head, so that the temperature of the shower head is maintained at a constant temperature. It becomes possible.

According to a preferred embodiment of the present invention, the channel is
Since it is placed on the circumference of the reaction vessel in a substantially horizontal plane and is arranged while being inverted with a circumference length shorter than the circumference of the horizontal plane, it is easy to machine and reacts at a relatively low manufacturing cost. A container or the like can be manufactured, and the reaction container or the like can be uniformly controlled to a predetermined temperature.

According to a preferred embodiment of the present invention, the flow path provided in the reaction container is defined by a rib protruding from the inner wall side formed between the inner wall and the outer wall of the reaction container. Since the rib is formed integrally with the member of the inner wall, the efficiency of heat transfer is high, and the amount of heat carried by the heat medium can be efficiently supplied to the inner wall of the reaction chamber.

According to a preferred embodiment of the present invention, at least one system is provided in each of the shower head and the reaction container for the flow path of the temperature control means configured to allow the heat medium to flow therethrough. The temperature of the shower head that requires accurate temperature control can be easily controlled.

According to the preferred embodiment of the present invention, since the shower head and the reaction vessel are provided with a plurality of systems of heat medium flow paths, the temperature of each part surrounding the reaction chamber can be uniformly controlled as necessary.

According to the preferred embodiment of the present invention, since the shielding plate is arranged between the stage and the reaction vessel, the radiant heat from the high heat stage can be shielded, and the temperature control of the reaction vessel becomes easy. .

According to the preferred embodiment of the present invention, since the fluorine-based liquid fluid is used as the heat medium, stable heat exchange can be performed with good heat transfer characteristics.

According to a preferred embodiment of the present invention, the vapor phase growth thin film is a metal oxide thin film, and the source gas is a metal source gas and an oxygen-containing gas. Therefore, strontium oxide / barium oxide having a very high dielectric constant is used. A thin film can be formed.

According to a preferred embodiment of the present invention, in vapor phase growth, the substrate is heated to a predetermined temperature, for example, by a heater built in the stage, and the temperature of each portion surrounding the reaction chamber such as the shower head is controlled by a plurality of temperatures. Since vapor phase growth is carried out while maintaining a constant temperature by using a means, it is possible to discharge a temperature-sensitive source gas for growing a thin film into the reaction chamber at a predetermined temperature. Therefore, a high-quality vapor phase growth thin film can be formed by using a source gas sensitive to temperature.

According to a preferred embodiment of the present invention, since the shower head has a hollow heat medium circulation space and is provided with a large number of nozzle tubes arranged in the space,
The nozzle tube exchanges heat with the heating medium and is heated to that temperature.
Therefore, if the temperature of the heating medium is controlled to, for example, 250 ° C. ± 2%, the gas flow passing through the nozzle holes is also heated to that temperature. Therefore, it is possible to supply the source gas having a high temperature and soaking and a uniform density over the entire surface of the shower head onto the substrate on which the film is to be formed.

According to the preferred embodiment of the present invention, the circulation path of the heat medium can be easily formed in the shower head. Therefore, it is possible to flow the heat medium to the shower heads without stagnating.

According to a preferred embodiment of the present invention, the nozzle tube has a cylindrical shape or a rectangular shape, and is arranged so as to be sandwiched between the first planar member and the second planar member so as to come into contact with the heat medium. Therefore, heat exchange can be easily performed between the gas flow passing through the nozzle hole and the heating medium, and a gas flow whose temperature is controlled to be high temperature / uniform temperature can be formed.

According to a preferred embodiment of the present invention, two systems of a plurality of circulation paths of the heat medium in the shower head have a portion arranged in parallel and adjacent to each other, and in the portions arranged in substantially parallel. The fluid flows are arranged so that the directions thereof are opposite to each other. Therefore, the temperature difference between the inflow side and the outflow side is canceled out, and the entire temperature of the shower head can be made uniform.

According to a preferred aspect of the present invention, the nozzle tube is formed integrally with the first or second planar member,
The welding work of a large number of single nozzle pipes is not required, and the problem of processing distortion associated with welding is eliminated. Further, the shower head can be easily processed.

According to the preferred embodiment of the present invention, since a large number of nozzle holes are provided in the rib of the shower head, the nozzle tube need not be manufactured and assembled. This eliminates the problem of processing distortion due to welding of nozzle pipes,
In addition, the shower head can be easily manufactured.

According to a preferred embodiment of the present invention, vapor phase growth of a metal oxide thin film or the like is performed by the vapor phase growth apparatus using the shower head having the above-mentioned structure, so that the source gas supplied onto the substrate is heated at high temperature. It is a soaking, constant-density gas stream. Therefore, it is possible to grow a vapor growth thin film having a uniform composition and a uniform thickness over the entire surface of the substrate. In particular, the metal-organic raw material gas is sensitive to temperature, and if the temperature control in the flow channel is not good, problems such as condensation and generation of reaction products to adhere to the pipeline are likely to occur. As described above, the raw material gas passes through the narrow nozzle hole,
Since the temperature is controlled to a predetermined value, it is possible to grow a good quality metal oxide thin film without causing clogging in the nozzle holes.

[0050]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings. In the drawings, the same reference numerals indicate the same or corresponding parts.

FIG. 1 shows a vapor phase growth apparatus according to an embodiment of the present invention. A space surrounded by the reaction container 10 and the susceptor 13 is a reaction chamber 11, in which the metal source gas discharged from the nozzle 18 of the shower head 16 reacts with the oxygen-containing gas and is placed on the susceptor 12. A metal oxide thin film is vapor-deposited on the substrate 13. Here, the metal source gas is, for example, Ba (DPM) ₂ , Sr (DPM) ₂ and Ti (i-O).
Organic metal such as C ₃ H ₇ ) ₄ is mixed, vaporized, and carried by a carrier gas such as Ar.
The oxygen-containing gas is a gas containing ozone (O ₃ ) in which an oxidizing gas such as O ₂ , N ₂ O and H ₂ O is ozonized by an ozonizer.

The reaction vessel 10 comprises a vessel-shaped vessel portion 10A surrounding the reaction chamber 11 and a support base portion 10B on which the vessel-shaped vessel portion 10A is mounted. The reaction chamber 11 is hermetically sealed by being placed on top. Reaction container 1 which is the upper space of the reaction chamber 11
A shower head 16 is arranged in the center of 0, and an upper space 17 of the shower head serves as an inlet for introducing holes 20 and 21 which communicate with the metal source gas and the oxygen-containing gas source. An opening is provided in the center of the support base 10B, which is the lower space of the reaction chamber 11, and a stage 12 on which a substrate 13 such as a semiconductor for growing a vapor phase thin film is placed is arranged in the opening. The stage 12 is supported by a support rod 25 and can be raised and lowered by an elevator mechanism 15.
The position of the illustrated stage 12 is a little lower than that at the time of vapor phase growth, and after completion of vapor phase growth, the substrate loading / unloading port 24
Then, the substrate 13 is loaded and unloaded from the substrate loading / unloading port 24 by a robot hand (not shown). The gate valve 19 is for opening and closing a substrate loading / unloading port 24 that communicates with a substrate transfer chamber (not shown).

The metal source gas is introduced through the gas introduction hole 21, the oxygen-containing gas such as ozone (O ₃ ) is introduced through the gas introduction hole 20, and the upper space 17 of the shower head 16 is introduced.
Are mixed and discharged from the nozzle 18 into the reaction chamber 11. In the reaction chamber 11, the metal source gas and the oxygen-containing gas react with each other to form metal oxide molecules such as barium titanate or strontium titanate, and a metal oxide thin film grows on the substrate 13 such as a semiconductor. Accumulate. The gas after the reaction and the surplus gas are exhausted from the reaction chamber 11 through the produced gas exhaust port 22.

In vapor phase growth of a metal oxide thin film, in order to form a good quality film, it is extremely important to control the reaction gas and the temperature of the substrate on which the film is formed. Substrate temperature is 4
It can be adjusted in the range of 00 to 700 ° C, for example, 55
Control of ± 1% at 0 ° C is required. Further, in order to control the temperature of the reaction gas, it is required that the temperature of the shower head and the inner wall of the reaction vessel is 250 to 260 ° C. and is controlled to about ± 2%. Therefore, the substrate heater unit 23 is built in the stage 12 on which the semiconductor substrate 13 is mounted, and the substrate heater unit 23 is arranged below the susceptor 14 on which the semiconductor substrate 13 is mounted.

In order to control the temperature of the reaction gas in the reaction chamber 11, the reaction gas is provided at a predetermined temperature around the kettle-shaped portion 10A of the reaction container, the support 10B, the shower head 16 and the reaction gas introduction holes 20 and 21. A heating medium flow path is provided for heating. Here, the heat medium is a liquid fluid used to circulate and heat the object to be temperature-controlled. For example, perfluoropolyether which is a fluorinated liquid fluid is used, and by using this, stable heat exchange can be performed, which is nonflammable, has no danger of ignition and explosion, and has good heat transfer characteristics. In addition to the above, as a heat medium, alkyldiphenyl, paraffin oil, mineral oil, silicone oil, or the like can be used.
In this embodiment, the heat medium has five channels.

Flow paths 31, 32, 3 of each of the first to fifth systems
3, 34 and 35 are kettle-shaped portions 10 of the reaction vessel, respectively.
The temperature of each part of A, the support base 10B and the shower head 16 can be controlled independently. Heat medium tank 3
6 is provided with a heater 37, and the heat medium in the tank is heated to the temperature set by the power adjusting unit 39. Then, by the pump 38, it is branched and sent to the flow paths of each system arranged in each part of the vapor phase growth apparatus. Thermocouple T0
Detects the oil temperature of the heat medium on the discharge side of the pump 38 and feeds it back to the electric power adjusting section 39, so that the oil heater 37 performs feedback control so as to maintain the temperature of the heat medium at a predetermined temperature. A flow rate adjusting valve 40 is provided in each branched system, and the amount of heat supplied to each part of the reaction vessel 10 is adjusted by adjusting the flow rate of the heat medium.

The first system and the fourth system are the heat exchanger 4
By passing through 1, it is possible to exchange heat with the cooling water, lower the temperature of the heat medium, and reduce the amount of heat supplied to the installation site of the flow path of the reaction vessel 10. The reaction vessel 10 surrounding the reaction chamber 11 and the shower head 16 have thermocouples T1 and T2.
, T3, T4, T5 are provided to detect the temperature near the inner wall of the reaction chamber in which the channels of each system are set. Thermocouple T1 to T
5 is connected to the temperature indicator 42, and the temperature of each part is displayed. The temperatures detected by the thermocouples T1 to T5 are sent to a controller (not shown), the opening of the flow rate adjusting valve 40 is adjusted so as to reach a predetermined temperature, and the flow rate of the heat medium is adjusted, whereby the reaction chamber The temperature of each part of the wall is controlled.

The flow path 31 of the first system is provided in the cylindrical portion at the open end of the support base 10B of the reaction container on the outer peripheral side of the stage 12, and is easily affected by the heat generated by the substrate heater unit 23. For this reason, the temperature of the inner peripheral portion of the support base 10B becomes high, and for example, in order to set the set temperature of the thermocouple T1 on the inner wall of the reaction chamber to 250 ° C., the adjustment of the flow rate by the flow rate adjustment valve 40 is not sufficient. Therefore, it is particularly effective to lower the temperature of the heat medium by the heat exchanger 41, which is a cooling means for the heat medium.

A skirt 23A, which is a shield plate connected to the stage 12, is provided between the stage 12 and the support base 10B of the reaction container provided in the vicinity of the stage 12 so as to be separated therefrom. As a result, the radiant heat from the heater 23 of the stage 12 is shielded, and the support base portion 1 of the reaction vessel is
OB temperature control can be facilitated.

Further, the flow path 34 of the fourth system provided in the shower head 16 sandwiches the reaction chamber 11 and the susceptor 1 is provided.
4, the temperature of the susceptor 14 is maintained at a high temperature, for example, 550 ° C. by the substrate heater unit 23. For this reason, since the susceptor 14 is close to the shower head 16 especially during vapor phase growth, the temperature of the shower head 16 portion tends to rise under the influence of this heat. Therefore, lowering the temperature of the heat medium in the flow path of the fourth system by the heat exchanger 41 is particularly effective in controlling the temperature of the shower head 16 within a temperature range of 250 ° C plus or minus 2%. is there.

Next, the flow path of each system is shown in FIG.
It will be described with reference to FIGS. In each flow path of each system, the heat medium circulates in every corner of the reaction vessels 10A and 10B,
In addition, it is formed by so-called one-stroke writing so that stagnation of oil does not occur on the way. For each flow path, a portion where temperature control accuracy is important, such as a portion near the inner wall of the reaction chamber 11, a portion near the heater 23 that heats the substrate 13, a portion near the nozzle 18 of the shower head 16, is arranged on the upstream side. There is.

The flow path 31 of the first system is arranged around the stage 12 and is provided in a cylindrical shape as shown in FIG. The flow path is arranged on the circumference of a substantially horizontal plane, rotates counterclockwise with a circumference length shorter than one circumference of the circumference, is connected to the flow path in the lower stage, and once again runs along the circumference of the horizontal plane. It rotates clockwise with a shorter circumference and moves to the next lower flow path on the circumference of the horizontal plane. By repeating this, the flow passages 31 arranged in the cylindrical portion of the central opening of the support base 10B of the reaction vessel can keep the temperature of the cylindrical portion at 250 to 260 ° C.
Can be soaked.

The channel 32 of the second system is provided in the disk-shaped portion of the support base 10B of the reaction container. Figure 3
The path | route of the flow path of a 2nd system is shown. As shown in the drawing, the flow path is arranged so that the inner circumference side, which requires temperature accuracy, makes one turn in a clockwise direction on the horizontal plane, moves to the outer circumference side, and heats the disk-shaped portion to every corner. There is.

The flow path 33 of the third system is arranged in the curved portion of the kettle-shaped portion 10A of the reaction vessel. The path of this flow path is shown in FIG. The flow passage moves to the upper flow passage immediately before making a clockwise turn on the horizontal plane circumference from the inlet, makes a round trip on the horizontal plane circumference counterclockwise, and moves to the further upper flow passage immediately before making one turn. Further, again, it makes one round in a clockwise direction on the circumference of the horizontal plane, and immediately before making one round, it moves to the upper flow path. By repeating this, the flow path is arranged on the entire surface of the reaction vessel 10 thus curved, and the vessel-shaped portion 10 of the reaction vessel is evenly distributed.
The curved part of A can be heated.

The flow path 34 of the fourth system is used for the shower head 1
It is provided in 6. FIG. 5 shows the path of this flow path. Since this flow path passes through the nozzle 18 immediately before the reaction gas is introduced into the reaction chamber 11, in the thin nozzle 18,
In order to prevent the reaction gas from condensing and adhering and the reaction product from adhering and causing clogging, it is necessary to control the temperature to a predetermined temperature particularly uniformly and accurately. For this reason, in the shower head 16 in the form of a disk, the flow path is provided in parallel in zigzag so as to be opposite to each other by bifurcating from the inlet in two directions and making a quarter turn, respectively. Each of the flow passages has a circumference of 1/4 and is combined with one flow passage to flow out.

The flow path 35 of the fifth system is provided with the reaction gas introduction hole 2
0, 21 and the upper space 17 of the shower head 16 are heated. FIG. 6 shows the path of this flow path. As shown in the figure, the upper surface of the shower head 16 has a disc-like structure, and the upper portion on the inner peripheral edge side is the introduction hole 2
It has a cylindrical structure surrounding 0 and 21. For this reason, the flow path moves counterclockwise around the same circumference in the counterclockwise direction and moves to the inner circumference side, and then to the inner circumference side in the clockwise direction and further moves to the inner circumference side. Next, the cylindrical portion is gradually moved to the upper stage side, and it is repeated counterclockwise and clockwise about one circle to move to the upper stage side.

FIG. 7 shows the cross-sectional structure of the flow path of the cylindrical portion of the first system, the third system, the fifth system and the like. For example, the kettle-shaped portion 10A of the reaction container has a structure in which a member 45 on the inner wall of the reaction container and a member 46 on the outer wall are attached to each other. Inner wall member 45
A rib 47, which is an integral member, projects from the. Then, the outer wall member 46 is electron beam or plug welded to the head of the rib 47, so that the inner wall member 45 and the outer wall member 46.
And are pasted together. The flow path 48 is defined by the rib 47 between the reaction chamber inner wall member 45 and the reaction chamber outer wall member 46. The processing of this inner wall 45 is
Since the groove on the same circumference is formed apart from the outer side of the cylindrical inner wall member 45 in the axial direction, machining by a lathe or the like is easy. For ribs that cannot be machined with a lathe or the like, the rib body is welded to the reaction chamber inner wall member 45 or machined with a milling machine or the like.

In the above embodiment, the heat exchanger 41
Is water-cooled, but it may be air-cooled. In this case,
A long metal pipe may be used. Further, in the embodiment described above, the flow path 48 is formed by the rib 47, but it may be configured by winding a pipe. Further, the temperature of each part of the reaction chamber controlled by the system of each flow path adjusts the oil amount of the heat medium by adjusting the opening degree of the flow rate adjusting valve 40 in the above-mentioned embodiment, but the oil amount is constant, An in-line heater may be provided for each system, and the temperature of each portion of the inner wall of the reaction vessel may be controlled to be constant by controlling the amount of heat supplied by the heater. Further, the amount of oil may be adjusted by adjusting the opening of the flow rate adjusting valve, and the temperature of each part of the reaction vessel may be controlled by using an in-line heater together. Thereby, the temperature control range can be further expanded.

Next, an example of vapor phase growing a metal oxide thin film using the above vapor phase growth apparatus will be described. First, the reaction chamber 11 is evacuated. Then, the stage 12 is lowered to the position of the substrate loading / unloading port 24 by the elevator mechanism 15, the gate valve 19 is opened, and the substrate 13 is placed on the susceptor 14 by a robot hand (not shown).
Then, the gate valve 19 is closed and the stage 12 is raised. The substrate 13 is heated to, for example, 550 ° C. ± 1% by the heater 23 built in the stage 12. Then, the pump 38 starts circulating the heat medium. The heat medium is heated by the heater 37 built in the tank 36 to the temperature set by the power adjusting unit 39.

Then, a temperature control device (not shown) detects the temperature of each part of the inner wall of the reaction vessel 10 by the thermocouples T1 to T5 and controls it to a constant temperature. That is, the control device (not shown) controls the opening degree of the flow valve 40 so that the temperature of each thermocouple becomes a preset temperature. During vapor phase growth, the stage 12 rises and moves to a position close to the shower head 16. At this time, the shower head 16
Is heated under the influence of the high temperature of the susceptor 14, but since the cooling device 41 is connected to the flow path 34 of the fourth system, by changing the flow rate of this cooling water, The temperature can be lowered. As a result, the shower head 16 can be moved to a position where the high temperature susceptor 14 is close to it, and the temperature can be maintained at a constant temperature of, for example, about 250 ° C.

In this state, the organometallic gas is supplied from the raw material gas introduction hole 21, the oxygen-containing gas containing ozone (O ₃ ) is supplied from the introduction hole 20, mixed in the upper space 17 of the shower head, and then the nozzle. It is discharged onto the substrate 13 on the stage 12 through 18. In the reaction chamber 11, a reaction between the metal source gas and the oxygen-containing gas occurs, metal oxide molecules are formed, and deposited on the substrate 13 to grow a vapor phase growth thin film. When the vapor phase growth is completed, the elevator mechanism 15
Thereby, the stage 12 is lowered to the position of the substrate loading / unloading port 24, the gate valve 19 is opened, and the substrate 13 is taken out by a robot hand (not shown).

In the above description of the embodiment, the kettle-shaped portion 10A of the reaction vessel 10, the support base portion 10B, and the shower head 16 are provided with five channels. However,
The number of flow paths is not limited to five, as long as it can maintain the inside of the reaction vessel and the supply path of the reaction gas at a constant temperature, and is appropriately set according to the configuration of the apparatus and the vapor phase growth conditions. do it.

FIG. 8 is a plan view of the shower head,
9 is a partial cross-sectional view taken along the line BB of FIG.
FIG. 11 is an enlarged view of part A in FIG. 9, and FIG. 11 is an enlarged view of part A in another embodiment.

The shower head 16 is provided between a disk-shaped first planar member (lower member) 25 facing the substrate side and a disk-shaped second planar member 26 facing the gas supply source side. It has a hollow part (space) sandwiched between. A rib 27 is erected from the member 26 side in the hollow portion (space) to define a heat medium circulation path. An annular protrusion 28 is provided near the outer circumference of the member 26, and a large number of nozzle tubes 18A (or 18B) are embedded on the inner circumference side. In FIG. 8, what is indicated by a dotted line in the figure is a circulation path of the heat medium. The nozzle tubes 18A (18B) are respectively arranged in the central portion of the heat medium circulation path.
The annular protrusion 28 is for fitting the shower head 16 to the kettle-shaped portion 10A of the reaction container.

In the shower head of this embodiment, two systems 34A and 34B are provided for the circulation path of the heat medium. The system 34A enters the hollow portion between the members 25 and 26 from the port 29A, is arranged zigzag as shown by the dotted line, and exits to the port 30A. Further, the system 34B enters from the port 29B and is similarly arranged in a zigzag manner by partitioning the hollow portion between the members 25 and 26 with the rib 27.
Exit to 0B. As shown, line 34A and line 34B
And in a zigzag manner on the entire surface of the shower head 16 evenly. And ports 29A and 29
Although not shown in the drawing, the flow path of the fourth system is divided into two and is supplied with the heat medium of the same temperature, although not shown. Since the inflow port 29A of the system 34A and the outflow port 30B of the system 34B are arranged close to each other, and the inflow port 29B of the system 34B and the outflow port 30A of the system 34A are arranged close to each other, the inflow side and the outflow side The temperature difference between and is canceled out, and the entire temperature of the shower head 16 can be made uniform.

As shown in the enlarged view of FIG. 10, the nozzle tube 1
8A has a nozzle hole 18 in the central portion, and is arranged in a heat medium circulation path in which a cylindrical outer peripheral portion is divided by ribs 27.
It is adapted to be immersed in a heat medium heated to a predetermined temperature. The nozzle tube 18A is fitted and fixed in the nozzle fitting holes of the member 25 and the member 26, respectively. The outer peripheral portion of the nozzle tube is welded to the members 25 and 26 over the entire circumference. In the present embodiment, the rib 27 is erected from the member 26 and abutted on the member 25, but it may be erected from the member 25 side and abutted on the member 26.

FIG. 11 shows an example of the structure of a nozzle portion using a nozzle tube 18B having a shape different from that of FIG. In this embodiment, after fixing the members 25 and 26 by welding or the like, the nozzle tube 18B may be inserted into a large number of fitting holes and the outer peripheral portion may be welded, so that the shower head assembly process is simplified.

FIG. 12 shows an example in which a cylindrical nozzle tube is integrally formed with a surface member of a shower head. A rib 27 is integrally formed on the first planar member 25, and a nozzle tube 18A is integrally formed on the first planar member 25. The nozzle hole 18 for discharging gas is provided in the center of the nozzle tube 18A as in the above-described embodiment. The upper end of the nozzle tube 18A is fitted into the second planar member 26 and sealed by welding. By integrally forming the nozzle tube with the planar member in this manner, the number of welded portions can be reduced, welding distortion can be prevented, and manufacturing becomes easy.

FIG. 13 shows an example in which the prismatic nozzle tube 18B is integrally formed with the planar member 25 of the shower head. Although the above-mentioned cylindrical nozzle tube is formed into a prismatic shape, the machining can be further facilitated by disposing the prismatic nozzle tube 18B in a grid pattern.

FIG. 14 shows an example in which nozzle holes are provided in the ribs. A cylindrical wall 25A is erected on the outer periphery of the first planar member 25 of the shower head, and ribs 27 are erected so as to be alternately inserted between them. Becomes The first planar member 25, the cylindrical wall 25A on the outer periphery of the first planar member 25, and the rib 27 are integrally formed. And
The rib 27 is provided with a large number of nozzle holes 18. Second
The planar member 26 has an opening 18H engaged with the nozzle hole 18, and when the second planar member 26 and the first planar member 25 are fixed to each other, the positions of the opening 18H and the nozzle hole 18 are Manufactured to fit. With such a structure, the heat medium can be made to flow uniformly in the flow path between the ribs 27 without stagnation, the temperature of the ribs 27 can be kept uniform, and as a result, the temperature of the nozzle holes can be kept uniform. Further, according to such a structure, since it is not necessary to manufacture the nozzle tube, it is possible to significantly reduce the time and labor of machining and welding. As a result, welding is reduced, welding distortion can be reduced, and the manufacturing cost of the shower head can be reduced.

FIG. 15 shows a further improved workability of the shower head having the above-described ribs provided with nozzle holes.
Ribs 27 are integrally formed in the shape of comb teeth in the first planar member 25 shown in FIG. 15B, and nozzle holes 18 are bored in the ribs 27. The ring-shaped member 25R shown in FIG. 15 (C) is a member fitted to the outer periphery of the rib 27,
The inner peripheral surface thereof is provided with a U-shaped recess 25U. Figure 1
5 (D) shows a state in which the members of (B) and (C) are fitted, and the recess 25U of the ring 25R forms the folded portion of the heat medium between the ribs 27. FIG. 15E shows a cross section taken along the line AA in which the lid member (second planar member) 26 is fixed to this.
It will be as shown in. According to this structure, unlike the embodiment shown in FIG. 14, since the folded portion of the heat medium flow path between the ribs is provided in the separate ring member, machining during production becomes extremely simple.

For vapor phase growth, the shower head 16 is used.
From a large number of nozzles 18 which are evenly arranged, the organometallic raw material gas and the oxygen-containing gas, which are controlled to have a high temperature and a uniform temperature, are mixed and discharged with a uniform density over the entire surface of the substrate. Therefore, it is possible to grow a metal oxide thin film having a uniform composition over the entire surface of the substrate at a uniform growth rate. Further, the organometallic raw material gas reacts very sensitively to temperature, but since it is controlled with high accuracy at high temperature and soaking as described above, a high quality metal oxide thin film can be grown. Similarly, before entering the reaction chamber 11, problems such as condensation in the narrow nozzle holes 18 or deposition of reaction products can be avoided.

In the above description of the embodiment, the circulation path of the heat medium is composed of the first planar member 25 and the second planar member 2.
6 and the rib 27, the pipe-shaped member is used instead to form the two channels 34A and 34B of the above-described arrangement, and the pipe-shaped member is combined and joined. You may do it. Also, shower head 1
6 is provided with two channels 34A and 34B. However, the number of channels is only required to be able to maintain the entire temperature of the shower head 16 at a constant temperature.
The number of systems is not necessarily two, and may be set appropriately according to the configuration of the apparatus and the vapor phase growth conditions.

Further, if the hollow portion (space) between the members 25 and 26 is finely divided into a plurality of sections and a circulation path for the heat medium is provided for each section, the length of each path can be shortened. Since it becomes possible, the temperature difference between the inflow side and the outflow side can be made small, and good temperature control is possible without providing the two paths as described above. Needless to say, even in this case, the two routes may be arranged as described above.

Further, in the vapor phase growth apparatus of the above-mentioned embodiment, the degree of vacuum in the reaction chamber during thin film formation is, for example, several T.
It is set to about orr. However, the degree of vacuum at the time of forming the thin film is not limited to this, and should be appropriately determined according to the conditions of the gas for forming the film.

In addition, although the present embodiment has described the example of vapor phase growth of a metal oxide such as barium titanate, it is applicable to vapor phase growth of a superconducting thin film using a rare earth element which requires strict temperature control. Of course, can also be used.

[0087]

As described above, according to the present invention, a flow path in which a plurality of systems of heat medium is circulated is provided around the reaction chamber of the vapor phase growth apparatus, and each flow path of each system is connected to each part of the reaction chamber. The temperature can be adjusted. Therefore, it becomes possible to adjust the temperature of the substrate portion and the reaction chamber portion, which undergo vapor phase growth, to predetermined temperatures with high accuracy. Therefore, according to the vapor phase growth apparatus of the present invention, a metal oxide thin film such as barium titanate can be grown under good growth conditions.

Further, since the flow paths of each system are returned to the same tank, reheated and circulated, the temperature of each part of the reaction chamber can be finely controlled with a relatively simple device configuration.

Further, according to the present invention, nozzle holes are evenly arranged in the shower head of the vapor phase growth apparatus, a circulation path for the heat medium is provided, and the nozzle tube is immersed in the path. Therefore, high temperature /
It is possible to discharge the source gas controlled to a predetermined temperature for soaking on the entire surface of the substrate with a uniform density.

Further, by arranging the nozzle hole in the stand or the tube which is erected on one surface member of the shower head, the number of welding points can be reduced and the machining of the shower head portion can be simplified.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a vapor phase growth apparatus according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a path of a first-system flow path.

FIG. 3 is an explanatory diagram showing a path of a flow path of a second system.

FIG. 4 is an explanatory diagram showing a path of a flow path of a third system.

FIG. 5 is an explanatory diagram showing a path of a flow path of a fourth system.

FIG. 6 is an explanatory diagram showing a path of a flow path of a fifth system.

FIG. 7 is a partial cross-sectional view of a reaction container.

FIG. 8 is a plan view of the shower head in FIG.

9 is a side partial cross-sectional view of the shower head in FIG.

FIG. 10 is an enlarged view of a nozzle portion.

FIG. 11 is an enlarged view of a nozzle portion of another embodiment.

FIG. 12 is an enlarged view of a nozzle portion of still another embodiment.

FIG. 13 is an enlarged view of a nozzle portion of still another embodiment.

FIG. 14 is a perspective view of an embodiment in which nozzle holes are arranged in ribs.

FIG. 15 is a perspective view of a lid (planar) member of another embodiment, (B) a perspective view of a planar member having ribs provided upright, and (C) a perspective view of a ring member. (D) A top view showing the path of the flow path of the heat medium, and (E) a sectional view taken along the line AA in (D).

[Explanation of symbols]

10 reaction vessels 10A reaction vessel kettle 10B Reaction vessel support 11 Reaction chamber 12 stages 13 board 16 shower head 31, 32, 33, 34, 35 flow paths 40 Flow control valve 18 nozzle holes 18A, 18B nozzle tube 25 First member 26 Second member 34A, 34B Heat medium circulation path

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor, Tsukamoto, 11-11 Haneda-Asahi-cho, Ota-ku, Tokyo Stock company Ebara Corporation (72) Inventor Masaru Nakaba 11-11, Haneda-Asahi-cho, Ota-ku, Tokyo Stocks Incorporated at the EBARA CORPORATION (72) Inventor Naoki Matsuda 11-1 Haneda Asahi-cho, Ota-ku, Tokyo Inside the EBARA CORPORATION (56) Reference JP-A-7-58101 (JP, A) JP-A-5 -343331 (JP, A) JP-A-5-335248 (JP, A) JP-A-57-50423 (JP, A) JP-A-58-153332 (JP, A) JP-A-63-307276 (JP, A) ) JP-A-4-349196 (JP, A) JP-A-4-364024 (JP, A) JP-A-8-218171 (JP, A) US Pat. No. 5273588 (US, A) (58) Fields investigated (Int .Cl ^7, DB name) C30B 1/00 -. 35/00 C23C 16/00 - 16/56 H01L 21/205 EURO AT (QUESTEL)

Claims (5)

(57) [Claims] 1. A stage on which a substrate is mounted, a shower head provided at a position facing the stage for discharging a raw material gas for growing a thin film on the substrate to the substrate, and a reaction container forming a reaction chamber. A thin film vapor deposition apparatus having: a first planar portion facing the substrate in the shower head;
Of the material and the second planar member facing the source gas supply side
A hollow heat medium circulation space is formed between the heat medium
Has a nozzle hole that penetrates both members in the circulation space
A plurality of nozzle tubes are provided, and the first planar member and the second planar member
A rib arranged between the planar members is provided, and by the rib, the front
A zigzag heat medium circulation path is provided on the entire surface of the shower head.
A thin film vapor phase growth apparatus characterized in that a film is formed . 2. The rib includes the first planar member and the second planar member.
Thin Makuki phase growth apparatus according to claim 1, characterized in that the nozzle holes through the planar member is disposed in. 3. The circulation path of the heat medium of the shower head is constituted by a plurality of paths, and the circulation path of the heat medium is two.
Claim strains has a portion which is arranged close substantially parallel, characterized in that the direction of flow of the fluid in portion arranged in the symbolic parallel are disposed so as to be opposite each 1 Alternatively, the thin film vapor phase growth apparatus according to item 2 . 4. The heat medium flowing through the plurality of paths,
Claim the same temperature of the heat medium is characterized in that it is provided
3. The thin film vapor phase growth apparatus described in 3 . 5. The heat medium is nonflammable and has heat conduction characteristics.
Fluorine-based fluid with good
Thin film vapor deposition apparatus according to claim 1 Symbol mounting, characterized in that heating the nozzle tube de a uniform temperature.