JPS645355Y2 - - Google Patents

Description

[Detailed description of the invention] Recently, there has been a device that performs heating by concentrating the light from a light source such as a halogen lamp or a xenon lamp using a reflecting mirror.
Radiation heating devices have come to be widely used for crystal growth, melting of various materials, and research on physical properties at high temperatures. For such purposes, the object to be heated (sample)
It is often required to heat the material to a high temperature in an atmosphere such as a special gas or high pressure.

Since radiation heating equipment uses light to heat,
The sample is placed in a chamber or container (atmosphere chamber) made of heat-resistant glass such as quartz, an atmospheric gas is introduced into the atmosphere chamber, and heating is performed by concentrating light from outside the atmosphere chamber. be exposed.

Since such an atmosphere chamber is made of glass, it is easily broken, and may be destroyed due to operator carelessness or the pressure of the atmosphere chamber. If such destruction occurs, atmospheric gas in the atmosphere chamber, evaporated matter from the sample, glass fragments, etc. may be released to the outside, potentially posing a danger to the operator.

Recently, semiconductors with unique properties, inorganic compounds,
Efforts are being made in various fields to discover or develop new materials such as ceramics and metals, but in such cases, dangerous conditions such as the use of toxic atmospheric gases, evaporation of toxic vapors from samples, and high-pressure atmospheres are necessary. is increasingly required. In such a case, the destruction of the glass atmosphere chamber as described above would expose the operator to an extremely dangerous situation, so there is a strong demand for improvements regarding the safety of the radiant heating equipment as described above. It has become like that.

The object of the present invention is to provide a highly safe apparatus that eliminates the danger to the operator due to the destruction of the glass atmosphere chamber in the above-mentioned radiation heating apparatus.

Figure 1 shows an example of a conventional radiation heating device.
This shows an apparatus that focuses the light of a halogen lamp using a spheroidal mirror to heat and melt a sample, growing crystals using a floating zone method.

In FIG. 1, 1 indicates a spheroidal mirror having a reflective surface on its inner surface, and 2 indicates a removable portion of the spheroidal mirror 1. This spheroidal mirror 1 has two focal points F ₁ and F ₂ . 3 is halogen lamp 3
(light source) located on the focal point _F1 . 4 represents a seed crystal, 5 represents a raw material rod, and 6 represents a melted portion. Furthermore, numeral 7 indicates a holding rod that holds the seed crystal 4, and numeral 8 indicates a holding rod that holds the material rod 5. Also,
9 is a quartz tube, 10 and 11 are holding cylinders for holding the quartz tube 9, 12, 12', 13, 1
3', 14, and 14' each indicate an O-ring. Furthermore, 15 represents an atmospheric gas inlet, 16 represents an atmospheric gas outlet, and 17 and 18 represent a substrate, respectively. Further, reference numeral 19 indicates an atmosphere chamber inside the quartz tube 9.

In FIG. 1, the halogen lamp 3 is placed on one focal point _F1 of the spheroidal mirror 1, so
After being reflected by the spheroidal mirror 1, the light is concentrated at the other focal point _F2 through the quartz tube 9. As a result, the joint between the seed crystal 4 and the raw material rod 5 is melted, and a fused portion 6 is formed. If this state is maintained and the holding rods 7 and 8 are slowly moved downward at the same speed, a new crystal will grow on the seed crystal 4.

As shown in FIG. 1, the quartz tube 9 is held by holding cylinders 10 and 11, and is provided so as not to come into contact with the spheroidal mirror 1 through an opening provided in the spheroidal mirror 1. In addition, the inner surface of the quartz tube 9,
The space surrounded by the holding cylinders 10, 11 and the substrates 15, 15' is occupied by O-rings 12, 12', 13, 13', 1
4 and 14', forming a sealed atmosphere chamber 19. By introducing a desired atmospheric gas into the atmospheric chamber 19 from the atmospheric gas inlet 15, the surroundings of the melting section 6 can be maintained in a desired atmosphere. If it is necessary to circulate the atmospheric gas, the atmospheric gas can be discharged from the atmospheric gas outlet 16 at a desired speed.

As mentioned above, the quartz tube 9 constitutes an atmosphere chamber, and at the same time serves to prevent vapor evaporated from the sample from adhering to the surface of the spheroidal mirror 1 and deteriorating its performance.

When growing crystals of substances with high vapor pressure at high temperatures, it is necessary to increase the pressure of the atmosphere to suppress evaporation.

Additionally, crystal growth of some materials must be carried out in an atmosphere of toxic gases.
(For example, GaAs crystal growth is carried out in an atmosphere containing As gas.) Also, when crystal growth is performed on some substances, toxic vapors evaporate from the sample (for example, As evaporates in the case of GaAs). On the other hand, in the apparatus shown in Fig. 1, there is a part of the quartz tube 9 that is exposed outside the spheroid mirror 1, and the quartz tube 9 may be broken due to carelessness by the operator. Also, the quartz tube 9 may burst if a pressure of about 30 atmospheres is applied to the inside and heated to a high temperature.

If the quartz tube 9 is destroyed when crystal growth is performed using a toxic atmosphere as described above, or when crystal growth is performed using a substance that evaporates toxic vapor, the toxic gas or vapor will evaporate. This could result in a release to the outside environment, exposing the operator to serious danger.

Furthermore, if the quartz tube 9 ruptures due to high pressure, its fragments will scatter and pose a hazard to the operator and the like.

As explained above, the conventional radiation heating apparatus shown in Fig. 1 has particular safety problems when growing crystals under normal conditions (safe atmospheric gas, sample with little evaporation, low pressure). However, as mentioned above, there is a high risk of crystal growth in high pressure or toxic atmospheres, or crystal growth of substances that cause evaporation of toxic vapors, and improvements are required.

Further, the atmosphere chamber 19 is usually constructed of a heat-resistant glass tube 9 such as quartz, and both ends thereof are sealed with O-rings 12, 12' to prevent leakage of atmospheric gas. Normally, when crystal growth is performed once, evaporated matter from the sample adheres to the inner wall of the quartz tube 9, so the quartz tube 9 must be replaced. However, as mentioned above, both ends of the quartz tube 9 are sealed by O-rings 12, 12'.
These O-rings 12, 12' must be completely tightened to prevent internal atmospheric gas from leaking.

It is difficult and dangerous to completely seal both ends of a fragile tube such as a quartz tube every time it is replaced.

Therefore, it is extremely important to facilitate the replacement of the quartz tube 9 in terms of safety and operability.

The object of the present invention is to provide a highly safe radiation heating device that eliminates the danger associated with damage to the atmosphere chamber, which is associated with the conventional radiation heating device as described above.

Figure 2 shows an embodiment of the present invention, in which the present invention is adopted in a crystal growth apparatus using a floating zone method using a radiation heating device using a halogen lamp as a light source, similar to the conventional example shown in Figure 1. It is shown.

In FIG. 2, 21 is a spheroidal mirror having two focal points _F1 and _F2 , 22 is a removable part of the spheroidal mirror 21, 23 is a halogen lamp, 24 is a seed crystal, and 25 is a material rod. , 26 is a melting part, 27 is a holding rod for holding the seed crystal 24, 28 is a holding rod for holding the material rod 25,
29 is a quartz tube, 30 and 31 are quartz tube holding cylinders,
32, 32' are simple seals, 33, 34, 3
4' is an O-ring, 35, 35', 35'' are atmospheric gas inlets, 36, 36', 36'' are atmospheric gas outlets,
37 represents an aperture, and 38 represents a substrate. Also, 39
indicates an atmosphere chamber inside the quartz tube 29.

Halogen lamp 2 installed at one focal point F ₁
The light of No. 3 is reflected by the reflecting mirrors 21 and 22 and concentrated at the other focal point F ₂ through the quartz tube 29, melting the joint between the seed crystal 24 and the material rod 25, and forming a melted part 26. Keep this state and hold the holding rod 2
When 7 and 28 are slowly moved downward at the same speed, a new crystal grows on top of the seed crystal 24. In this respect, this embodiment also functions exactly the same as the conventional example shown in FIG.

In the embodiment of the present invention shown in FIG. 2, the interior of the spheroidal mirror 21 is sealed by O-rings 33, 34, 34'. Further, although the socket portion of the halogen lamp 23 is not shown, it is sealed using an O-ring or a hermetic seal, and the cavity inside the spheroidal mirror 21 is completely sealed and isolated from the outside air. There is.

Further, the quartz tube 29 is installed inside the spheroidal mirror 21 as shown in the figure. Spheroidal mirror 21
The inside of the quartz tube 29 is sealed with simple seals 32 and 32', and the circulation of atmosphere between the atmosphere chamber 39 and the cavity inside the spheroidal mirror 21 is prevented. . Therefore, the melting section 26
The vapor evaporated from the spheroidal mirror 21 will not adhere to the surface of the spheroidal mirror 21 and reduce the reflectance.

The space formed between the inside of the quartz tube 29 and the inside of the holding cylinders 30 and 31 is filled with simple seals 32, 32'.
and are sealed with O-rings 34, 34'.
A sealed atmosphere chamber 39 is formed. A desired atmospheric gas can be introduced into the atmosphere chamber 39 from the atmospheric gas inlet 35 . Further, when it is necessary to circulate the atmospheric gas, the atmospheric gas can be discharged from the atmospheric gas outlet 36 at a desired speed.

The atmospheric gas inlet 35 is branched into two flow paths 35' and 35'' as shown in the figure, the atmospheric gas entering 35' enters the atmosphere chamber, and the atmospheric gas entering 35'' flows through the spheroidal surface. Enter the cavity inside the mirror 21. Further, the atmospheric gas that has entered the atmospheric chamber is discharged through the atmospheric gas outlet 36'. Further, the atmospheric gas that has entered the interior of the spheroidal mirror 21 is discharged through the atmospheric gas outlet 36''.The atmospheric gas outlets 36' and 36'' merge to form 36.
Connected to a predetermined outlet.

As mentioned above, since the atmospheric gas is simultaneously introduced into the interior of the atmosphere chamber 39 and the interior of the spheroidal mirror 21 surrounding the exterior thereof, the seals 32 and 32' at both ends of the quartz tube 29 do not need to be so tight. do not have. For example, as shown in FIG. 3, the tip of a relatively flexible rubber seal 32 may be in contact with the surface of the quartz tube 29 to prevent the free flow of atmospheric gas.

In addition, if it is extremely difficult to prevent the evaporated material from the melted part 26 of the sample from leaking into the interior of the reflecting mirror 21 through the seal 32 or 32', as shown in FIG. It is preferable to provide an aperture 37 at 36''.By doing this, the pressure inside the spheroidal mirror 21 becomes slightly higher than the pressure inside the atmosphere chamber 39, so that the melting part 2
6 can be prevented from leaking into the interior of the spheroidal mirror 21 through the seal 32 or 32'.

However, in normal cases, there is often no problem even if the diaphragm 37 is not provided.

As mentioned above, in the present invention, the seals 32, 3
Since 2' can be a simple one, the quartz tube 29 can be replaced extremely easily. The procedure for replacing the quartz tube 29 in the embodiment of the present invention shown in FIG.
Explain using diagrams. FIG. 4 shows a state in which the removable portion 22 of the spheroidal mirror 21 has been removed from the state shown in FIG. Further, the numbers of each element are the same as in FIG. 2.

In FIG. 4, when installing the quartz tube 29, the quartz tube 29 is tilted as shown in the figure and inserted into the seal 32, and the upper end of the quartz tube 29 is slightly inserted into the space inside the holding tube 30. After the quartz tube 29 is placed vertically, the lower end of the quartz tube 29 is inserted into the seal 32'.
installation is completed. By subsequently attaching the removable portion 22 of the spheroidal mirror 21,
The state shown in FIG. 2 can be set. Also,
The quartz tube 29 can be removed by performing the above-described procedure in reverse.

As mentioned above, since the seals 32 and 32' are flexible, they do not provide much resistance when the quartz tube 29 is attached or removed, and the seals 32 and 32' are flexible.
It can be removed very easily.

In addition, in the embodiment of the present invention shown in FIG. 2, the quartz tube 29 is installed inside the sealed spheroidal mirror 21, and the operator may accidentally break the quartz tube 29 during operation of the device. Nothing like that happens. Furthermore, even if the quartz tube 29 breaks due to the pressure or high temperature of the atmospheric gas, its fragments, toxic atmospheric gas, toxic evaporated matter from the molten part 26, etc. will be released to the outside of the sealed spheroidal mirror 21. Never released.

In this way, in the present invention, since the atmosphere chamber 39 using heat-resistant glass is provided inside the sealed spheroidal mirror 21, there is no risk associated with breakage of the heat-resistant glass that existed in conventional devices. A highly safe radiant heating device that completely eliminates this has been realized.

In addition, as mentioned above, in the device of the present invention, the quartz tube 2
9 is extremely easy to replace, and from this point of view, there is also an effect of high safety and high operability.

In the above explanation, a radiation heating device is shown as an example in which a light source is provided at one focal point of a single spheroidal mirror and the radiation heating device heats the other focal point by concentrating the light. The same effect can be obtained in a heating device that includes two or more spheroidal mirrors and concentrates the light from a light source on the focal point of each spheroidal mirror.

Figure 5 shows an example of a radiation heating device that combines a plurality of spheroidal mirrors as described above, and a heating device with two spheroidal mirrors facing each other is applied to crystal growth using the floating zone method. Indicates the case where

In FIG. 5, 41 and 42 are spheroidal mirrors, 43 and 44 are halogen lamps, 45 is a seed crystal, 46 is a material rod, 47 is a melting part, and 48 and 49 are for a seed crystal 45 and a material rod 46, respectively. holding rod, 50 is a quartz tube, 51 and 52 are quartz tubes 50
holding cylinder, 53, 53' is a simple seal, 54,
55, 55' are O-rings, 56, 56', 56'' are atmospheric gas inlets, 57, 57', 57'' are atmospheric gas outlets, 58 is an aperture, and 59 is a substrate. Further, 60 indicates an atmosphere chamber inside the quartz tube 50.

Two spheroidal mirrors 41 and 42 having two focal points F ₁ and F ₂ and F ₁ ′ and F ₂ ′ are provided facing each other so that F ₂ and F ₂ ′ coincide, Two halogen lamps 43 and 4 provided on F ₁ and F ₁ ′
By concentrating the light of No. 4 on F ₂ and F ₂ ', the sample can be heated and melted to grow crystals using a floating zone method.

Inside the spheroidal mirrors 41 and 42 is an O-ring 5.
4, 55, and 55'. (The spheroidal mirror 42 can be removed from the spheroidal mirror 41.) Note that the halogen lamp 4
Although socket parts 3 and 44 are not shown, O
It is sealed with a ring or hermetic seal.

The quartz tube 50 is thus provided in the sealed spheroidal mirrors 41 and 42. Furthermore, the quartz tube 50 can be
The spheroidal mirrors 41 and 42 are sealed to prevent atmospheric gas from entering inside them. Therefore,
Steam evaporated from the melting part 47 is transferred to the spheroidal mirror 4.
It is possible to prevent the particles from adhering to the reflective surfaces 1 and 42 and reducing the reflection efficiency.

Similar to the embodiment shown in FIG. 2, the atmospheric gas is branched from the atmospheric gas inlet 35 to 35', 35'' and introduced into both the interior of the atmospheric chamber 60 and the cavity formed by the spheroidal mirrors 41 and 42. Therefore, the seals 53 and 53' at both ends of the quartz tube 50 may be simple seals as shown in FIG.
By providing a
Since the pressure inside the melting part 47 is higher than that of the
The evaporates from the atmosphere chamber 60 pass through the spheroidal mirror 4.
1, 42 can be completely prevented from leaking. However, there are many cases where this diaphragm 58 is omitted without causing any problem.

In the embodiment shown in FIG. 5, as in the embodiment shown in FIG. 2, the quartz tube 50 is not exposed to the outside.
An operator accidentally accidentally damaged the quartz tube 50 while operating this device.
An accident that would destroy the equipment cannot occur. Further, even if the quartz tube 50 ruptures due to atmospheric pressure or high temperature, fragments of the quartz tube, toxic atmospheric gas, toxic evaporated substances, etc. will not leak to the outside.
Furthermore, the quartz tube 50 can be replaced very easily by the procedure shown in FIG. 4, as in the case of the embodiment shown in FIG.

In this way, the embodiment shown in FIG. 5 also realizes a radiation heating device with excellent safety and operability.

Although the above description has been made using a halogen lamp as a light source, it is clear that the same effect of the present invention can be obtained even when any lamp such as a xenon lamp or a mercury lamp is used as a light source.

In addition, in the embodiments of FIGS. 1, 2, and 3, the holding bars 7 and 8, or 27 and 28
Alternatively, the case where 48 and 49 are slowly moved downward has been explained, but the spheroidal mirror 1,
Alternatively, it is also possible to perform crystal growth by moving 21 or 51 and 52, and in such a case, all the effects of the present invention are similarly exhibited.

Furthermore, although the above explanation describes the case where the radiation heating device is applied to crystal growth using the floating zone method, other methods such as crystal growth (e.g. epitaxial growth), sample melting, sample heating, etc. It is clear that the effects of the present invention can be obtained in exactly the same way even when applied to.

Further, although one embodiment of the seals 32, 32' or 53, 53' at both ends of the quartz tube 29 or 50 is shown in FIG. 3, various shapes of the seals are conceivable. However, the effectiveness of the present invention does not depend on the shape of this seal.

Furthermore, in FIGS. 2 and 5, it was stated that the part 22 or 42 of the spheroidal mirror is removable, but it is possible to open and close these parts to the rest of the spheroidal mirror using a hinge or the like. It may be attached to.

[Brief explanation of the drawing]

Figure 1 shows an example of a conventional radiation heating device.
1 is a spheroidal mirror, 3 is a halogen lamp, 4 is a seed crystal, 5 is a raw material rod, 6 is a melting part, 9 is a quartz tube, 1
2, 12', 13, 13', 14, and 14' are O-rings, 15 is an atmospheric gas inlet, 16 is an atmospheric gas outlet, and 19 is an atmospheric chamber. FIG. 2 shows an embodiment of the present invention, in which 21 is a spheroidal mirror, 23 is a halogen lamp, 24 is a seed crystal, 25 is a material rod, and 26
29 is a fused portion, 29 is a quartz tube, 32, 32' are simple seals, 33, 34, 34' are O-rings, 35 is an atmospheric gas inlet, 36 is an atmospheric gas outlet, and 39 is an atmospheric chamber. FIG. 3 is an enlarged view of one embodiment of a simple seal 32 that seals both ends of the quartz tube 29 in FIG. FIG. 4 is a diagram for explaining the procedure for replacing the quartz tube 29 in the embodiment shown in FIG.
Same as the figure. FIG. 5 shows another embodiment of the present invention, 41 and 42 are spheroidal mirrors, 43 and 44
is a halogen lamp, 45 is a seed crystal, 46 is a material rod, 50 is a quartz tube, 53 and 53' are simple seals,
54, 55, and 55' are O-rings, 56 is an atmospheric gas inlet, 57 is an atmospheric gas outlet, and 60 is an atmospheric chamber.

Claims (1)

[Scope of utility model registration request] A light source is provided at one focal point of one or more spheroidal mirrors, and the light is concentrated at the other focal point,
In a radiation heating device for heating an object disposed inside a removable heat-resistant glass tube, the removable glass tube is installed in a cavity surrounded by the spheroidal mirror, and the removable glass tube is installed in the cavity surrounded by the spheroidal mirror. and a radiation heating device characterized by having a structure for introducing atmospheric gas into a glass tube, and a structure for discharging atmospheric gas from the cavity and the glass tube.