JPH08259384A - Closed tube-type epitaxial growth device - Google Patents

Abstract

PURPOSE: To produce an epitaxial layer having an excellent quality with slight contamination by separating a chamber keeping a substrate from a chamber keeping a source plate and connecting between both of the chambers by a solution guiding path capable of moving only in one direction in a closed tube- type liquid phase epitaxial growth device using a rotation-type gradient method. CONSTITUTION: A closed tube 2 divided into two chambers 4 and 5 by a rotation shaft 1 and a partition wall 3 is horizontally kept rotatably about the rotation shaft 1. These two chambers are connected by a solution guiding path 7. In the figure, R1-R4 indicate rotating positions of the closed tube 2 and figures (a)-(c) show respective vertical cross section at the rotating position R4. At the position R4, the solution 8-4 kept in the chamber 4 flows into the chamber 5 passing through the solution guiding path 7. This solution is not able to go back into the chamber 4. A substrate 11 is kept in the chamber 5 at a position not in contact with the solution 8 when it is at a rotating position 4. After the temperature of the solution 8 transferred into the chamber 5 reached a growing temperature, the closed tube 2 is rotated and brought into contact with the substrate 11 to perform epitaxial growth.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a closed tube type liquid phase epitaxial growth apparatus using a rotary tilt method. A closed tube type liquid phase epitaxial growth apparatus using a gradient method is widely used for liquid phase epitaxial growth (LPE growth) of a compound semiconductor such as HgCdTe used in an infrared detector, which has a high vapor pressure and is easily decomposed. The tilt method encloses a source material, an epitaxial substrate, and a solution in a sealed tube, separates the solution in contact with the source material from the source material by tilting the sealed tube, and contacts the epitaxial substrate for LEP growth. This is a liquid phase epitaxial growth method.

In the LPE method, in order to make the solution composition constant, it is desirable to bring the solution into contact with the source material at a predetermined temperature to make a saturated solution, and then to cool the solution to a growth temperature for epitaxial growth.

Therefore, there is a need for a closed-tube type liquid phase epitaxial growth apparatus capable of transferring only the solution to the growth chamber after bringing the melt and the source into contact with each other to saturate them at a predetermined temperature.

[0004]

2. Description of the Related Art For liquid phase epitaxial growth of semiconductors,
Immersion method, boat slide method or tilt method (chipping method)
Is mainly used. FIG. 8 is a cross-sectional view of a conventional example, showing a cross section of a liquid phase epitaxial growth apparatus.

In the dipping method, referring to FIG. 8A, the substrate holder 4 is immersed in the solution 41 in the crucible heated by the heater 44.
The epitaxial substrate 42 held horizontally at 3 is immersed to deposit and deposit a semiconductor on the surface of the substrate 42. Also,
In the boat slide method, referring to FIG. 8 (b), the substrate 42 is embedded in a recess in the upper surface of the substrate holder 43 whose upper surface is horizontally installed, and the upper surface of the substrate holder 43 is penetrated to hold the solution 41. Slide the slider 45 having a mouth,
The solution 41 is moved onto the substrate 42.

In the dipping method and the boat slide method,
Although a mechanism for moving the substrate holder 43 or the slider 45 is required, it is difficult to arrange these mechanisms in a closed tube, and it is usually constructed as an open tube type liquid phase epitaxial growth apparatus.

In the tilting method, referring to FIG. 8 (c), a substrate 42 is placed at one end of a high position of a tubular furnace which is placed tilted,
After holding the solution 41 at the other end at the lower position and raising the temperature to a predetermined temperature, the solution 41 is brought into contact with the substrate 42 to deposit a semiconductor as shown in FIG. .

There is a rotary tilting method as another method of the tilting method.
FIGS. 8D and 8E show cross sections of a tubular furnace to which the rotary tilting method is applied. Referring to FIG. 8D, a sealed tube 32, which is manufactured by sealing both ends of the tube, is provided horizontally, and the sealed tube 3
2 is provided on the lower surface of the substrate holder 30 provided on the upper part of the substrate 38.
And the melt 35 is held at the bottom so as not to come into contact with the substrate 38 and heated. After the temperature is raised, the sealed tube 32 is rotated 180 degrees around its central axis, and the substrate 38 is immersed in the melt 35 to deposit the semiconductor.

The above-described tilting method allows the melt to be moved only by tilting or rotating the furnace body, and does not require any mechanical moving means in the furnace, and thus can be easily applied to a closed tube type liquid phase epitaxial growth apparatus. Is. In particular, the rotary tilt method has the advantage that the device structure is simple. Therefore, a closed-tube liquid-phase epitaxial growth system using the tilt method, especially the rotary tilt method, is often used for the deposition of semiconductors with high vapor pressure and easy decomposition.

However, the closed tube type growth apparatus cannot adopt a method of sequentially depositing semiconductors on a large number of substrates from the same solution by using a large amount of solution like the dipping method. For this reason, a small amount of solution must be weighed for each growth, and it is difficult to keep the composition constant for each growth due to the difficulty of precise measurement of trace components.

It is also difficult to adopt a method such as the boat slide method in which the solution composition and the source substrate are brought into contact with each other every time they are deposited on one substrate to bring them into an equilibrium state so that the solution composition is kept constant. is there. Therefore, in the closed-tube type growth apparatus, there is a problem that the semiconductor composition varies greatly from substrate to substrate.

In order to solve this problem, a liquid phase epitaxial growth apparatus which can use a source plate in the rotary tilting method was devised and is disclosed in Japanese Patent Laid-Open No. 59-79534.

In this growth apparatus, referring to FIG. 8 (e), a substrate holder 30 having an L-shaped cross section is provided in a cylindrical sealed tube 32 having a horizontal rotation axis, and an L-shaped substrate holder 30 is formed on the inner wall of the sealed tube 32. It is provided so that the upper end is in close contact. Further, the substrate 38 and the source plate 40 are held on both sides of the L-shaped vertical portion. First, the sealed tube 32 is fixed at a rotational position where the substrate 38 and the source plate 40 are held horizontally, and the raw material is melted to form the solution 35.
Next, after reaching a predetermined temperature, the sealed tube 32 is rotated counterclockwise by 180 °, and the solution 35 is moved onto the source plate 40 and held until it becomes a saturated solution. Then, the sealed tube 3
2 is rotated clockwise by 360 ° to bring the substrate 38 into contact with the solution 35 below the cylindrical sealed tube 32 to perform epitaxial growth.

According to this growth apparatus, since the solution can be brought into contact with the source plate to be saturated, the composition fluctuation can be reduced. However, it requires a large amount of solution to immerse the substrate. Further, since the raw material and the source plate are extremely easily oxidized, the oxide generated on their surface floats on the surface of the solution, which causes a problem of crystal growth. Furthermore, since the substrate is held in the same chamber as the source material and the solution raw material to raise and lower the temperature, the substrate surface may be contaminated. In particular, a material whose melting temperature is lower than that of the substrate cannot be used as the source material. Furthermore, semiconductors having different compositions cannot be stacked and grown.

Among these problems, Japanese Patent Laid-Open No. 62-163334 discloses a closed tube type liquid phase epitaxial growth apparatus using a rotary tilting method capable of removing oxides floating on the surface of a solution.

FIG. 8F is a vertical sectional view of the growth apparatus. The rotating shaft 31 passing through the center of the sealed tube 32 is installed horizontally. The inside of the sealed tube 32, which is partitioned by the side plates 39 provided at both ends of the sealed tube 32, is divided into two by a partition wall 33 provided at the center thereof. In one of the divided chambers, a substrate 38 is horizontally provided above the rotary shaft 31 of the sealed tube 32. The raw material 36 is enclosed in the other chamber. The two chambers are connected by a thin communication pipe 34 provided at the lower end of the partition wall 33.

The sealed tube 32 is inserted into a tubular furnace and the temperature is raised to melt the raw material 36. The solution 35 passes through the communication pipe 34 at the lower end of the partition wall 33 and flows into the chamber holding the substrate 38. Next, after the temperature is lowered to the growth temperature, the sealed tube 32 is attached to the rotary shaft 31.
Epitaxial growth is performed by rotating around and immersing the substrate 38 in the solution.

In this apparatus, the oxide 37 of the raw material 36 floats on the surface of the solution and cannot pass through the narrow communicating pipe 34.
Therefore, since the oxide does not enter the chamber holding the substrate 38, a semiconductor with few defects can be deposited.

However, this device is not provided with a device for holding the source material and forming a saturated solution. Even if this is combined with the above-mentioned rotary device that holds the source material, the temperature must be raised and lowered while holding the substrate, the source material, and the solution in the same chamber, and the contamination of the substrate cannot be avoided. In addition, the problem that the source material is not a pollutant and the source material is limited to solid matter is unavoidable. Furthermore, the composition that can be epitaxially grown is determined by the source material, the solution composition, and the temperature at the time of contact.
In particular, semiconductors having different dopants cannot be stacked and grown.

[0020]

As described above, in the conventional sealed tube type liquid phase epitaxial crystal growth apparatus, since the substrate and the source plate are held in one chamber, the source material is limited and the substrate is contaminated. There is a problem. Further, since the solution composition cannot be changed, there is a drawback that epitaxial growth layers having different compositions cannot be stacked and grown.

According to the present invention, in a sealed tube type liquid phase epitaxial growth apparatus using a rotary inclination method, a chamber for holding a substrate and a chamber for holding a source plate are separately provided, and only one of them is used as a solution. , Which are connected to each other by a solution introduction path capable of moving, melts the raw material into a solution, raises the temperature, contacts the source plate and causes supersaturation, and the epitaxial growth process in separate chambers. It is an object of the present invention to provide a closed-tube liquid phase epitaxial growth apparatus that can be performed, has less source material restrictions, and has less contamination.

It is another object of the present invention to provide a closed-tube type liquid phase epitaxial growth apparatus capable of continuously depositing epitaxial growth layers having different compositions.

[0023]

1 is a sectional view showing the principle of the present invention, FIG. 5 is a sectional view showing a second embodiment of the present invention, and FIG. 6 is a sectional view showing a third embodiment of the present invention. (A), FIG.
(A) and FIG. 6 (a) are vertical cross sections parallel to the rotation axis of the liquid phase epitaxial growth apparatus, and FIGS.
(E) represents a cross section perpendicular to the rotation axis.

The first constitution of the present invention for solving the above-mentioned problems is, with reference to FIG. 1, a sealed tube 2 having a horizontal rotary shaft 1, and a inside of the sealed tube 2 in the direction of the rotary shaft 1. A first chamber 4 and a second chamber 5 separated by a dividing wall 3 and an inlet 7a in the first chamber 4, and the first chamber 4 and the second chamber 5 are connected to each other. 1 is provided with a solution introducing passage 7 for supplying the solution, and the inlet 7a is provided at a position higher than the highest position of the solution surface in the second chamber 5, and the second configuration is as shown in FIG.
In the closed tube type epitaxial growth apparatus having the first configuration, the floor surface 5a of the second chamber 5 is
The third configuration is characterized in that it is provided on the outer peripheral side of the sealed tube 2 with respect to the floor surface 4a, and the sealed tube 2 having a horizontal rotating shaft 1 is referred to with reference to FIG. , First and second chambers 4, 5 separated by a partition wall 3 that divides the sealed tube 2 in the direction of the rotation axis 1, and first and second chambers 4, 5 penetrating the partition wall 3. First and second solution introduction paths 7 for connecting
And the floor surfaces 4a, 4b of the first chamber 4 are provided at a position higher than the solution surface flowing into the second chamber 5 at the first rotation position R4 of the sealed tube 2, Further, it is provided at a position lower than the floor surface 5b of the second chamber at the second rotation position R3 of the sealed tube, and the first solution introducing passage 7 is provided at the first rotation position R4 at the first rotation position R4. The second solution introducing passage 9 is provided at a position lower than the vicinity of the floor surface 4a of the chamber 4, and the second solution introducing passage 9 has the second rotating position R3.
In the second chamber 5 is provided at a position lower than the vicinity of the floor surface 5b of the second chamber 5, and the fourth configuration is
With reference to FIGS. 1 and 5, a sealed tube 2 rotatably provided around a horizontal rotary shaft 1 and a solution holding chamber 4 provided in the sealed tube 2 adjacent to the rotary shaft 1 direction. And the growth chamber 5 and the substrate 11 provided on the inner wall surface of the growth chamber 5 in parallel with the rotation axis 1.
A substrate holder 11a for holding the surface and a source plate 12 provided on the inner wall surface of the solution holding chamber 4 in parallel with the surface of the substrate 11
Source holder 12a for holding the surface and the solution holding chamber 4
And a growth chamber 5 are connected to each other, and a tubular solution introduction path 7 is provided from the solution holding chamber 4 toward the growth chamber 5 and away from the rotation shaft 1, and the sealed tube 1 is rotated. Then, the solution 8-1 held in the solution holding chamber 4 is brought into contact with the source plate 12, and then the sealed tube 1 is rotated again to make the solution 8-1.
And a sealed tube rotating means for causing the solution to flow out into the growth chamber 5 through the solution introducing passage 7, and the fifth structure has a horizontal rotating shaft 1 with reference to FIG. The sealed tube 2 includes a solution holding chamber 4 for holding a solution and a source plate 12 inside the chamber, a growth chamber 5 for holding an epitaxial substrate 11 inside the chamber, and a dopant holding chamber 6 for holding a dopant material 13 inside the chamber. 3 inside the 2 in the direction of the axis of rotation
They are provided in this order separated by the first and second partition walls 3a and 3b to be divided, and connect the solution holding chamber 4 and the growth chamber 5 at the first rotation position R4 of the sealed tube 2. A first solution introducing passage 7-1 provided in the first partition wall 3a for allowing the solution held in the solution holding chamber 4 to flow into the growth chamber 5;
At the second rotation position R3 of the sealed tube 2, the second solution introducing passage 7-2 provided in the second partition 3b for transferring the solution in the growth chamber 5 to the dopant holding chamber 6 And the sealed tube 2
At a third rotation position R4, the third solution introducing passage 9 provided in the second partition 3b for transferring the solution in the dopant holding chamber 6 into the growth chamber 5 is provided. Configure as a feature.

[0025]

In the first construction of the present invention, referring to FIG. 1, the sealed tube 2 partitioned into the two chambers 4 and 5 by the partition wall 3 intersecting with the rotary shaft 1 of the sealed tube is arranged around the rotary shaft 1. It is horizontally held rotatably (may be in one direction, or may be forward / reverse rotation if necessary). The two chambers are connected by a solution introduction path 7. The partition wall 3 may be a flat surface or a curved surface as long as it intersects with the rotating shaft 1, and it need not be orthogonal to the rotating shaft 1.

In the figure, R1 to R4 represent the rotational positions of the sealed tube 2, and in FIGS. 1A to 1C, they represent the vertically downward directions corresponding to the four rotational positions. Note that FIG.
(A)-(c) represents the vertical cross section in the rotation position of R4.

At the rotational position R4 of the sealed tube 2, the solution 8-4 held in the first chamber 4 flows into the second chamber 5 through the solution introducing passage 7. The inlet 7a of the solution introducing passage 7 opening to the first chamber 4 is provided at a position higher than the highest liquid level of the solution 8 flowing into the second chamber 5 at the rotation position R4. Therefore, the solution 8 once flowing into the second chamber 5 does not return to the first chamber 4 again through the same solution introducing passage 7 even if the rotation position of the sealed tube 2 changes. That is, the solution introducing passage according to the present invention transfers the solution in only one direction.

The position of the surface of the solution 8 in the second chamber 5 is appropriately set to the position of the floor surface 5a of the second chamber 5 and the shape of the second chamber, for example, the cross sectional shape, the vertical sectional shape, and the size. By designing it, the required position can be achieved.

Next, a method of using the liquid phase epitaxial device of this structure will be described. First, set the rotation position to R1,
The raw materials are held in the first chamber 4 and heated and melted to form a solution 8-1. Next, the sealed tube 2 is rotated and the rotational position is set to R4.
By this rotation, the solution 8-1 moves inside the sealed tube 2 by, for example, 90 degrees.
Move to the position of solution 8-4. Therefore, the solution 8-4 flows into the solution introducing passage 7 from the inlet 7a of the solution introducing passage 7 and is transferred to the second chamber 4.

The substrate 11 is held in the second chamber 4 at a position where it does not come into contact with the solution 8 at the rotation position R4. Then, after the temperature of the solution 8 transferred to the second chamber 5 reaches the growth temperature, the sealed tube 2 is rotated to bring the solution 8 into contact with the substrate 11 to perform epitaxial growth.

In the liquid phase epitaxial device of this constitution, the steps from the dissolution of the raw materials to the holding of the dissolved solution, and further to the holding of the source plate and the supersaturation of the solution, if necessary,
The process of epitaxial growth on the substrate can be performed in a different chamber. Therefore, the contamination of the substrate that occurs during the formation of the solution or the formation of the saturated solution can be made extremely small. Furthermore, this configuration can be applied even if the raw material is a liquid at room temperature.

In the second configuration of the present invention, this rotational position R
4, the floor surface 4a of the first chamber 4 is formed at a position higher than the highest liquid level of the solution 8 flowing into the second chamber 5. In the present specification, the “floor surface” of the chamber means the surface that is the bottom of the chamber provided inside the sealed tube at the specified rotation position of the sealed tube 2, that is, the inner wall surface below the chamber in the vertical direction. To do. In addition, a solution introducing path 7 connecting the first and second chambers 4 and 5
Is provided below the floor surface 4a of the first chamber in the higher position of these chambers 4, 5. Therefore, the solution introducing path 7 can transfer the solution from the first chamber to the second chamber.

Further, in this structure, since the liquid level of the solution flowing into the second chamber is lower than the floor surface of the first chamber, all the solution in the first chamber is transferred to the second chamber. You can move. On the other hand, it is possible to completely prevent the solution from returning from the second chamber to the first chamber.

In the third configuration of the present invention, referring to FIG. 5, two solution introducing passages are provided between the two chambers 4 and 5. The first solution introducing passage 7 transfers the solution from the first chamber 4 to the second chamber 5 at the first rotation position R4 of the sealed tube,
It is similar to the second configuration of the present invention described above. Therefore, when the sealed tube 2 is placed at this rotation position R4, all the solution is transferred to the second chamber 5.

The second solution introducing passage 9 transfers the solution from the second chamber 5 to the first chamber 4 at the second rotational position R3 of the sealed tube, and has the above-mentioned first construction of the present invention. Is the same as. Therefore, in this configuration, a part of the solution can be left in the second chamber 5. It should be noted that the second solution introducing passage 9 may be transferred to the first chamber in the same manner as the second configuration, so that the entire solution is transferred.

In this structure, the sealed tube 2 is moved to the two rotational positions R
4, by rotating alternately to bring to R3,
The solution can be transferred alternately between the two chambers 4, 5. Therefore, the solution used for growth can be introduced into another chamber, brought into contact with the source material or the doping material, and then used again for growth. Therefore, epitaxial growth with different compositions can be continued. It is also possible to provide the source material at two locations in one chamber and select either one depending on the rotation position to bring it into contact with the solution. Therefore, it is possible to stack two or three types of epitaxial growth layers having different compositions.

In the fourth structure of the present invention, referring to FIG. 1, the solution holding chamber 4 and the growth chamber 5 are provided adjacent to each other in the sealed tube 2 side by side in the direction of the horizontal rotation axis 1. An epitaxial substrate 11 and a source plate 12 are held in the solution holding chamber 4 and the growth chamber 5 in parallel with the rotation axis 1. This board 1
1 and the source plate 12 can be brought into contact with the solution by rotating the sealed tube 2 to a rotation position R2 where the substrate 11 and the source plate 12 are located below. The solution holding chamber 4 and the growth chamber 5 are connected by a tubular solution introducing passage 7 provided in a direction away from the rotary shaft 1 from the solution holding chamber 4 to the growth chamber 5. The solution introducing path 7 is provided at a rotation position R4 of the sealed tube 2.
In the above, since it inclines downward, the solution 8-4 in the solution holding chamber 4 is reliably transferred into the growth chamber 5. The inclined solution introducing passage 7 can also be applied to the first or second configuration.

In the apparatus of this structure, the solution 8-1 in the solution holding chamber 4 is rotated by bringing the sealed tube 2 into contact with the source plate 12, and then the sealed tube 2 is rotated again to introduce the solution 8-1 into the solution. Road 7
Flow into the growth chamber 5 through the sealed tube 2 after reaching the growth temperature.
Is rotated to bring the solution 8 into contact with the substrate 11 to perform epitaxial growth. In this equipment, the melting of raw materials,
It is possible to raise and lower the solution temperature and transfer the solution without contacting the solution with the source plate or the substrate. In addition, the source plate, the raw material, and the substrate are separately placed in a separate chamber. Therefore, these processing temperatures can be freely set without considering the contamination of the substrate, and a wide range of compositions can be controlled.

The fifth structure of the present invention will be described with reference to FIG.
A dopant holding chamber 6 is added to the liquid phase epitaxial growth apparatus having the solution holding chamber 4 and the growth chamber 5 described in the fourth configuration.

The solution held in the growth chamber 5 and contacted with the source plate by the rotation of the sealed tube 2 to be saturated, passes through the first solution introducing passage 7-1 at the first rotation position R4 of the sealed tube 2 to form a solution. It is transferred from the holding chamber 4 to the crystal growth chamber 5. In addition, the solution introduction path of this configuration allows the solution to flow in one direction and does not allow backflow. The solution introducing path can be configured in the same manner as the solution introducing paths according to the first to fourth configurations described above.

The transferred solution is held in the growth chamber, reaches the growth temperature, and then contacts the substrate for epitaxial growth. After that, the solution in the crystal chamber 5 is transferred to the dopant holding chamber 6 by rotating the sealed tube 2 to the second rotation position R3.

The dopant material 1 is placed in the dopant holding chamber 6.
3 is held, and after the transferred solution reaches a predetermined temperature, the sealed tube 2 is rotated to bring the solution into contact with the dopant material 13 to make a saturated solution. Next, the sealed tube 2 is rotated to the third rotation position R4, and the solution in the dopant holding chamber 6 is transferred to the growth chamber 5 again through the third solution introducing passage 7-2. At this time, even if the third rotation position and the second rotation position are the same, backflow from the growth chamber 5 to the solution holding chamber will not occur if the solution introduction path of the present invention is used. The third rotation position and the second rotation position may be different. The invention of this configuration can also be applied to a liquid dopant material.

In this structure, the epitaxial growth using the solution saturated by contacting the source material and the epitaxial growth using the solution contacting the solution with the dopant material can be continuously performed.

In this configuration, a solution introducing passage for transferring the solution from the growth chamber 5 to the solution holding chamber 4 can be added at the fourth rotation position of the sealed tube 2. At this time,
The fourth revolution 1 is all different. With this configuration,
The transfer of the solution between the growth chamber 5 and the solution holding chamber 4 and the transfer of the solution between the growth chamber 5 and the dopant material holding chamber 6 can be performed independently.

Therefore, the epitaxial growth by the first solution saturated by contacting the source plate and the epitaxial growth by the second solution saturated by contacting the dopant material can be alternately superposed. This makes it possible to manufacture a deposited layer in which two types of layers are alternately laminated.

[0046]

EXAMPLES Details of the present invention will be described with reference to examples.
FIG. 2 is a perspective view of the first embodiment of the present invention and shows a partially cutaway view of the sealed tube. 2 is the rotational position R4 of FIG.
The vertical axis is the Y axis and the horizontal axes are the X and Z axes.

Referring to FIG. 2, the horizontal axis Z axis is set to the rotary axis 1
(It is also a cylinder axis.) A sealed tube 2 made of a quartz cylinder.
However, both ends thereof are partitioned by quartz or carbon side plates 14 so as to enclose the solution.

The inside of the sealed tube 2 partitioned by the side plate 14 is further divided into a solution holding chamber 4 and a growth chamber 5 by a partition wall 3 made of quartz or carbon. The solution holding chamber 4 and the growth chamber 5 are each provided with a source holder 12a made of quartz or a carbon plate.
And it is vertically divided by the substrate holder 11a. The source plate 12 made of plate-shaped HgCdTe is held on the lower surface of the source holder 12a, and the CdTe substrate 11 is held on the lower surface of the substrate holder 11a as an epitaxial substrate.

FIG. 3 is a diagram for explaining the operation of the first embodiment of the present invention, showing XY cross sections of the solution holding chamber 4 and the growth chamber 5 at various rotational positions of the sealed tube. 3A shows a cross section of the solution holding chamber 4 at the same rotation position as in FIG.
(A) shows a cross section of the growth chamber 5 at the same rotation position as in FIG. 2.

Referring to FIGS. 2 and 3A, the solution holding chamber 4 is a member made of quartz or carbon having a cross-sectional shape obtained by horizontally cutting the upper portion of an arc shape, and the upper surface thereof is the source holder 12a. Is provided with a floor material 15 that is in close contact with the lower surface of the and the side surface is in close contact with the inner wall surface of the sealed tube 2 in the X-axis direction. This floor material 15
Is the solution holding chamber 4 partitioned by the source holder 12a.
It is provided to raise the floor surface of the lower part in the X-axis direction.

The partition 3 is provided with one solution introducing passage 7. The solution introducing passage 7 has an inlet 7a opening near the surface of the floor material 15 in the lower part of the solution holding chamber 4 and an outlet 7b extending horizontally and opening in the growth chamber 5 near the wall surface of the sealed tube 2. Have. The inlet 7a of the solution introducing passage 7 is provided at a position higher than the surface of the solution 8 at the rotational position shown in FIGS. ) And (C)), it is provided at a position higher than the surface of the solution 8.

In this embodiment, first, the sealed tube 2 is attached to the structure shown in FIGS.
The solution raw material, which is fixed at the rotational position shown in (a) and (A) and weighed, is placed on the floor of the solution holding chamber 4, and both ends of the sealed tube 2 are vacuum-sealed. Then, the temperature is raised to melt the raw material to form a solution 8. The solution 8 accumulates in the lower part of the solution holding chamber 4 with reference to FIG. At this time, since the surface of the solution 8 is below the inlet 7a, the solution 8 is kept in the growth chamber 5 holding the substrate 11.
Does not flow into. After the raw materials are melted, the temperature is lowered, and this state is maintained until the temperature stabilizes at a predetermined temperature.

Next, the sealed tube 2 is rotated 180 ° counterclockwise toward the paper surface. 3 (b) and 3 (B) show the 90 ° rotational position in the middle, and FIGS. 3 (c) and 3 (C) show 180 ° rotational positions.
Indicates the rotated position. During this rotation, the surface of the solution 8 is always lower than the inlet 7a, so that the solution does not flow into the growth chamber 5. By this rotation, referring to FIGS. 3C and 3C, the solution 8 is brought into contact with the surface of the source plate 12 and maintained as it is until it is saturated.

Then, the sealed tube 2 is further rotated counterclockwise by approximately 9
It is rotated by 0 ° and brought to the rotational position shown in FIGS. In this rotating position, the floor material 15 is located below the solution holding chamber 4 with reference to FIG.
The upper surface of 5 serves as the floor surface of the solution holding chamber 4. Since the inlet 7a of the solution introducing passage 7 is opened at the same height as this floor surface, when the floor surface becomes substantially horizontal, the solution holding chamber 4
All of the solution 8 in the solution flows into the growth chamber 5 through the solution introducing passage 7 except for solid matters such as oxides. The solution flowing into the growth chamber 15 has its surface lower than the upper surface of the floor material 15 in the solution holding chamber and does not come into contact with the substrate 11 in the growth chamber, the holding position of the substrate 11, the amount of the solution and the volume of the growth chamber. Is designed.

Further, the sealed tube 2 is rotated counterclockwise by 90 ° to the initial rotation position with reference to FIGS. 4 (e) and 4 (E). At this rotation position, the temperature is lowered and maintained until the solution temperature reaches the growth temperature.

Next, the sealed tube 2 is rotated counterclockwise by 180 °. After passing through the figures (f) and (F) showing the position rotated by 90 °, the solution 8 contacts the surface of the substrate 11 with reference to the figures (g) and (G) at the position rotated by 180 °. Epitaxial growth is performed.

After the epitaxial growth, referring to FIGS. (H) and (H), the sealed tube 2 was further rotated by 180 °,
The solution 8 and the substrate 11 are separated. The direction of rotation may be counterclockwise or clockwise. Finally, the entire sealed tube is cooled to complete the epitaxial growth.

In this embodiment, even if the temperature rise overshoot occurs when the raw materials are melted, the solution does not come into contact with the source plate and therefore does not contain an excessive source composition.
The solution composition becomes stable.

In the above process, FIG. 3 (c) and (C)
180 ° clockwise from the position shown in Fig. 3 (a)
Also, the solution is brought to the same state as in (A), and in this state, the solution temperature can be lowered close to the growth temperature. Then, the solution 8 is transferred to the growth chamber by rotating it again by 90 ° in the clockwise direction to the rotation position shown in FIGS. With this method, it is possible to avoid the situation where the solution 8 and the substrate 11 are exposed to high temperature in the same chamber, so that the contamination of the substrate is reduced.

In the second embodiment of the present invention, referring to FIG. 5, the substrate holder 11a for horizontally holding the substrate 11 on the lower surface in the growth chamber 5 and the source plate 12 for the lower surface in the solution holding chamber 4 are shown in FIG. The source holder 12a that holds the growth chamber 5 and the solution holding chamber 4 vertically in the same manner as in the first embodiment.
It is provided in minutes. 5 shows a cross section of the sealed tube 2 at a rotation position R4 (a rotation position in which the R4 direction is vertically downward). FIG. 5 (a) is a vertical cross section, and FIGS. 5 (b) and 5 (c) are growth diagrams, respectively. A cross section of the chamber 5 and the solution holding chamber 4 is shown.

The solution holding chamber 4 is provided with a floor material 16 for forming a floor surface 4a parallel to the holding surface of the source plate 12 of the source holder 12a. The growth chamber 5 has a substrate holder 11
Floor material 17 for forming a floor surface 5b perpendicular to the holding surface of a
Is provided.

The inlet 7a of the solution introducing passage 7 for transferring the solution from the solution holding chamber 4 to the growth chamber 5 is provided near the floor surface of the floor material 16. On the other hand, the solution is transferred from the growth chamber 5 to the solution holding chamber 4
The inlet 9a of the solution introducing passage 9 for transferring to the floor material 17 is provided near the floor surface of the floor material 17.

First, referring to FIGS. 5 (b) and 5 (c), the rotational position of the sealed tube 2 is set to R1. That is, the sealed tube 2 is rotated and fixed so that the R1 direction is vertically downward. Next, the raw material of the solution is put into the solution holding chamber 4, heated and melted by heating to obtain a solution. Then, the sealed tube 2 is rotated 90 ° counterclockwise.
The solution is rotated to the rotation position R2, and the solution is brought into contact with the source plate 12 to form a saturated solution.

Then, the sealed tube is rotated 180 ° to the rotation position R4.
Rotate. As a result, the floor surface 4a of the solution holding chamber 4 becomes the upper surface of the floor material 16. On the other hand, the floor surface 5a of the growth chamber 5 becomes the inner wall surface of the sealed tube 2. Therefore, the solution accumulated on the upper surface of the floor material 16 is transferred to the lower floor surface 5 a of the growth chamber 5.

Next, after maintaining the growth temperature until reaching the growth temperature, the sealed tube 2 is rotated counterclockwise by 180 °, that is, the rotation position R1 and then the rotation position R2.
The solution is contacted with and the epitaxial growth is performed.

Next, the sealed tube 2 is brought to the rotation position R3. At this time, the floor surface 5b of the growth chamber becomes the upper surface of the floor material 17, while the floor surface 4b of the solution holding chamber 4 becomes the inner wall surface of the sealed tube 2. Therefore, all the solution flows out into the solution holding chamber 4. In this state, the sealed tube 2 is cooled and the epitaxial growth is completed.

In this structure, since the solution is not left in the growth chamber after the epitaxial growth, the surface of the epitaxial layer can be prevented from being contaminated. The third embodiment of the present invention relates to an apparatus provided with a solution holding chamber 4 and a dopant holding chamber 6 which are separated from each other by partition walls 3a and 3b on the left and right sides of a growth chamber 5 with reference to FIG.

FIG. 6 (a) is a longitudinal section of the entire sealed tube 2 at the rotational position R4, FIG. 6 (b) is a transverse section of the dopant holding chamber, and FIGS. 6 (c) and 6 (d) are partition walls 3b and 3, respectively. 3a
6 (e) shows the cross section of the growth chamber at a position close to, and FIG. 6 (e) shows the cross section of the solution holding chamber 4.

In the solution holding chamber 4, referring to FIG. 6 (e), a source holder 12a and a floor material 16 for partitioning the top and bottom of the cylindrical sealed tube 2 horizontally are provided. The plate-shaped source material 12 is horizontally held on the lower surface of the source holder 12a.

In the growth chamber 5, referring to FIGS. 6 (c) and 6 (d), the substrate holder 11a for partitioning the cylindrical sealed tube 2 horizontally,
Further, a floor material 17 is provided which is in close contact with the lower surface of the substrate holder 11a and vertically partitions the cylindrical sealed tube 2. The epitaxial substrate 11 is held on the lower surface of the substrate holder.

In the dopant holding chamber 6, as in the solution holding chamber 4 described above with reference to FIG.
Holder 13a for horizontally partitioning the upper and lower sides
And floor material 18 are provided. The plate-shaped dopant material 13 is horizontally held on the lower surface of the dopant holder 13a.

Partition wall 3 separating the solution holding chamber 4 and the growth chamber 5
A solution introduction path 7-1 having an inlet 7-1a is provided in a near the floor surface of the solution holding chamber 4 (upper surface of the floor material 16).
The partition wall 3b separating the growth chamber 5 and the dopant holding chamber 6 has a solution introducing path 7-2 for transferring the solution from the dopant holding chamber 6 to the growth chamber 5, and a solution from the growth chamber 5 to the dopant holding chamber 6. A solution introducing path 9 for transferring is provided. The solution introducing passage 7-2 has an inlet 7-2a near the floor surface (upper surface of the floor material 18) of the dopant holding chamber, and the solution introducing passage 9 has a floor surface of the growth chamber 5 at the rotation position R3 ( Entrance 9a near the surface of the floor material 17 exposed to the growth chamber 5)
Have.

Next, the operation of this embodiment will be described. FIG. 7 is a diagram for explaining the operation of the third embodiment of the present invention, showing the relationship between the rotational position of the sealed tube 2 and the movement of the solution. The arrow in the figure indicates the position of the solution introduction path.

First, referring to FIG. 6, the sealed tube 2 is placed at the rotation position R1 and the raw materials in the solution holding chamber 4 are melted to form a solution. At this time, referring to FIG. 7A, the solution 8 is held in the solution holding chamber 4 without touching the source plate 12. At this rotation position, the three solution introducing paths 7-1, 7-
2, 9 are located above the solution surface. In this state, the temperature is lowered to a predetermined temperature and waits until a constant temperature is reached.

Next, the sealed tube 2 is rotated 90 ° counterclockwise to the rotation position R2. With reference to FIG. 7B, the solution 8
Collects on the source holder 12a and contacts the source plate 12. Let stand as it is until the solution is saturated.

Then, the sealed tube 2 is rotated to the rotation position R4. Referring to FIG. 7C, at this time, the solution 8 in the solution holding chamber flows into the growth chamber 5 through the solution introducing passage 7-1.
At the same time, the temperature is lowered and the solution is left to stand until it reaches the growth temperature.

Then, the sealed tube 2 is rotated 180 ° counterclockwise, that is, through the rotational position R1 to the rotational position R2. As a result, referring to FIG. 7 (d), the solution 8 accumulates on the substrate holder 11a, comes into contact with the solution 8, and epitaxial growth is performed.

After the epitaxial growth, the sealed tube 2 is rotated 90 ° counterclockwise to the rotation position R3. With reference to FIG. 7E, the solution 8 is separated from the substrate 11 and the floor material 17
After falling on the upper surface, it flows into the dopant holding chamber 6 through the solution introducing passage 9.

Next, after the temperature is raised again to a constant temperature, the sealed tube 2 is rotated clockwise by 90 ° and placed at the rotation position R2.
Referring to FIG. 7F, the solution 8 is the dopant holder 13
It collects on a and contacts the dopant material 13. Leave as it is until saturated.

Next, the sealed tube 2 is rotated by 180 ° and placed at the rotation position R4. With reference to FIG. 7G, the solution 8 drops onto the upper surface of the floor material 18 in the dopant holding chamber 6, and the solution introduction path 7
-2 to flow into the growth chamber 5. In this state, the solution 8 is left to stand until it reaches the growth temperature.

After the solution reaches the growth temperature and stabilizes,
The sealed tube 2 is rotated counterclockwise, that is, 180 ° to the rotational position R2 via the rotational position R1. Referring to FIG. 7 (h), the solution 8 is brought into contact with the substrate 11 to be epitaxially grown.

After the growth, the sealed tube 2 is set to the rotation position R3, the solution 8 is caused to flow into the dopant holding chamber, and it is cooled to end the epitaxial growth. In this embodiment, two kinds of semiconductor layers can be sequentially epitaxially grown with a very simple apparatus.

[0083]

According to the present invention, since the steps of contacting the source plate with the solution to saturate and the epitaxial growth step are performed in separate chambers, the contamination of the substrate is small,
A good quality epitaxial layer can be manufactured. Further, according to another configuration of the present invention, epitaxial layers having different compositions can be sequentially deposited. Therefore, the present invention largely contributes to the improvement of the characteristics of the semiconductor device.

[Brief description of drawings]

FIG. 1 is a sectional view for explaining the principle of the present invention.

FIG. 2 is a perspective view of a first embodiment of the present invention.

FIG. 3 is a diagram for explaining the operation of the first embodiment of the present invention (No. 1)

FIG. 4 is a diagram for explaining the operation of the first embodiment of the present invention (No. 2)

FIG. 5 is a sectional view of a second embodiment of the present invention.

FIG. 6 is a sectional view of a third embodiment of the present invention.

FIG. 7 is an operation explanatory diagram of the third embodiment of the present invention.

FIG. 8 is a sectional view of a conventional example.

[Explanation of symbols]

 1 rotating shaft 2 sealed tube 3 partition wall 4 chamber (solution holding chamber) 4a, 4b, 5a, 5b floor surface 5 chamber (growth chamber) 6 dopant holding chamber 7, 9 solution introduction path 7a, 9a inlet 7b, 9b outlet 8 solution 11 Substrate 11a Substrate holder 12 Source plate 12a Source holder 13 Dopant material 14 Side plate 15, 16, 17, 18 Floor material 30, 43 Holder 31 Rotating shaft 32 Sealed tube 33 Partition wall 34 Communication tube 35, 41 Solution 36 Raw material 37 Oxide 38 , 42 substrate 39 side plate 40 source plate 44 heater 45 slider

Claims (5)

[Claims] 1. A sealed tube having a horizontal rotating shaft, a first chamber and a second chamber separated by a partition wall dividing the sealed tube in the rotating shaft direction, and an inlet for the first chamber. And a solution introducing passage connecting the first chamber and the second chamber, wherein the inlet is provided at a position higher than the highest position of the solution surface in the second chamber. Closed tube epitaxial growth system. 2. The closed-tube epitaxial growth apparatus according to claim 1, wherein the floor surface of the second chamber is provided on the outer peripheral side of the sealed tube with respect to the floor surface of the first chamber. Closed tube type epitaxial growth equipment. 3. A sealed tube having a horizontal axis of rotation, first and second chambers separated by a partition dividing the inside of the sealed tube in the direction of the axis of rotation, and first and second chambers penetrating the partition. A first and a second solution introducing passage connecting the two chambers, and a floor surface of the first chamber is a solution surface flowing into the second chamber at the first rotation position of the sealed tube. It is provided at a higher position and at a position lower than the floor surface of the second chamber at the second rotational position of the sealed tube, and the first solution introducing passage is provided at the second rotational position at the first rotational position. The first solution chamber is provided at a position lower than the vicinity of the floor surface, and the second solution introduction path is provided at a position lower than the vicinity of the floor surface of the second chamber at the second rotation position. Closed tube type epitaxial growth equipment. 4. A sealed tube rotatably provided around a horizontal rotation axis, a solution holding chamber and a growth chamber provided in the sealed tube adjacent to the rotation axis direction, and provided on a wall surface of the growth chamber. A substrate holder for holding the substrate surface parallel to the rotation axis, a source holder provided on the wall surface of the solution holding chamber for holding the source plate surface parallel to the substrate surface, the solution holding chamber and the growth chamber. And a tubular solution introducing path provided in a direction from the solution holding chamber to the growth chamber and away from the rotation axis, and the sealed tube is rotated to be held in the solution holding chamber. A closed-tube liquid phase, comprising: a sealed tube rotating means for rotating the sealed tube again after bringing the solution into contact with the source plate to allow the solution to flow out to the growth chamber through the solution introduction path. Epitaxial growth equipment. 5. A sealed tube having a horizontal axis of rotation, a solution holding chamber for holding a solution and a source plate in a chamber, a growth chamber for holding an epitaxial substrate in a chamber, and a dopant holding chamber for holding a dopant material in the chamber, The inside of the sealed tube is divided into three parts in the direction of the rotation axis and is provided in this order by being divided by first and second partition walls, which connects the solution holding chamber and the growth chamber to each other. At the second rotation position of the sealed tube and the first solution introducing passage provided in the first partition wall for flowing the solution held in the solution holding chamber to the growth chamber at the rotation position of A second solution introducing passage provided in the second partition for transferring the solution in the chamber to the dopant holding chamber,
A third solution introducing passage provided in the second partition wall for transferring the solution in the dopant holding chamber into the growth chamber at the third rotation position of the sealed tube. Tube type liquid phase epitaxial growth system.