JPH10212192A - Method for growing bulk crystal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the yield of single crystals in a desired growth direction by growing a bulk crystal by using a sheet-like seed crystal substrate of which the surface is inclined at a specific angle with the face of a prescribed bearing at approximately the same diameter as the diameter of the crystal to be grown. SOLUTION: The sheet-like seed crystal substrate 12 which has approximately the same diameter as the diameter of the crystal to be grown and of which the surface is inclined by the angle within a range of >=2 deg.C and below half the angle to produce the next order face with the face of the prescribed bearing is fixed to the bottom of a crucible 10 by a retaining member 15. A compd. semiconductor raw material and solute are put into the crucible 10 and this crucible is installed in a quartz ampoule 4 which is then vacuum sealed. This quartz ampoule is installed in a heating furnace and is heated by a heater 3 to melt the compd. semiconductor raw material and the solute to form a soln. 5. The ampoule 4 is then moved from the high-temp. side to the low-temp. side and the single crystal is gradually glow upward of the soln. 5 from the seed crystal 12 side.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for growing a bulk crystal, and more particularly, to a technique useful for producing a single crystal of a compound semiconductor from a melt or a solution using a large-diameter seed crystal.

[0002]

2. Description of the Related Art Conventionally, as a method of growing a bulk single crystal of a compound semiconductor, a growth vessel (crucible) containing a raw material melt is gradually and vertically moved relatively to a heating furnace having a temperature gradient. A vertical Bridgman (VB) method of growing a crystal by moving it, and a vertical gradient freezing (VGF) method of growing a crystal by providing a vertical temperature gradient in a raw material melt and gradually cooling it are known. ing. In the VB method and the VGF method, as shown in FIG. 4, usually, a crucible 1 formed in a mortar shape in which the bottom of the crucible 1 is inclined so as to descend toward the center thereof is used.
Then, a seed crystal 2 having the same composition as the crystal to be grown and having a considerably smaller diameter than the straight body of the crystal to be grown is placed at the center of the bottom of the crucible 1 having the above shape, and the temperature profile in the furnace is controlled by controlling the output of the heater 3. While adjusting, the raw material melt 5 is solidified from the seed crystal 2 in the quartz ampule 4 to obtain a bulk single crystal 6. Alternatively, without using a seed crystal, a bulk single crystal is obtained by solidifying the raw material melt by naturally generating a nucleus at the center of the bottom of the crucible.

In addition, as a method for growing a bulk single crystal of a compound semiconductor, a raw material melt in a crucible is covered with a sealing agent such as B ₂ O ₃ and a seed crystal is brought into contact with the surface of the raw material melt to gradually form it. There is a liquid-sealed Czochralski (LEC) method for growing a crystal by pulling it up, and it is widely practiced.
The seed crystal used at this time also has the same composition as the crystal to be grown and has a considerably smaller diameter than the straight body of the crystal to be grown, as in the case of the VB method or the VGF method.

However, II- such as CdTe and ZnTe
Since the group VI compound semiconductor has low thermal conductivity and low shear stress, the conventional VB method, VGF method and LEC method have a drawback that a high-quality single crystal cannot be obtained with high yield. In addition, the conventional VB method and VG
The F method also has a disadvantage that a new nucleus is generated during the growth of the crystal shoulder from the bottom center of the crucible to the straight body, and polycrystal is easily formed. Furthermore, in the conventional VB method, VGF method, and LEC method, since a shoulder is formed in the crystal, the length of the straight body is short, and there is a disadvantage that the number of wafers that can be cut out from the grown crystal is small. .

In order to overcome the above-mentioned drawbacks, there has been proposed a method of growing a crystal having a small shoulder portion by using a seed crystal having a larger diameter than in the prior art in the VB method, the VGF method, and the LEC method. Since the shoulder does not completely disappear, the above-described drawback of polycrystallization of the grown crystal due to nucleation during growth of the shoulder remains unresolved. Further, in the case of II-VI group compound semiconductors such as CdTe and ZnTe, it is difficult to obtain a large-diameter seed crystal such as CdTe or ZnTe, so that it is extremely difficult to apply a crystal growth method using a large-diameter seed crystal. Further, since the seed crystal has the same composition as the crystal to be grown, a part of the seed crystal that comes into contact with the raw material melt at the time of seeding is melted. There is also a disadvantage that temperature control is extremely difficult.

Therefore, the applicant of the present invention has previously disclosed a melt having a melting point higher than the growth temperature of the crystal to be grown as a seed crystal, a component different from that of the crystal to be grown, and containing a constituent element of the crystal to be grown. Alternatively, a crystal growth method using a thin single-crystal substrate having low solubility in a solution, for example, a substrate made of sapphire (aluminum oxide: Al ₂ O ₃ ) has been proposed (International Application No. PCT / JP95 / 02025). FIG. 1 schematically shows an apparatus used for carrying out the crystal growth method. The bottom of the crucible 10 is formed flat, and a thin seed crystal substrate 12 having a diameter substantially equal to the diameter of the straight body of the grown crystal can be placed on the bottom of the crucible 10. Then, a seed crystal substrate 12 made of a component different from that of the crystal to be grown and having substantially the same diameter as the diameter of the straight body of the grown crystal is fixed to the bottom of the crucible 10 by a pressing member 15. While adjusting the temperature profile inside, the seed crystal substrate 12 in the quartz ampoule 4 is adjusted.
By solidifying the raw material melt (or solution) 5 from the above, a bulk single crystal having no shoulder can be obtained. For example, a sapphire substrate is used as the seed crystal substrate 12, and Te and Zn are used.
ZnTe from a solution containing Te as a solvent and a solute, respectively.
A single crystal is grown.

[0007]

However, according to our subsequent research, according to the above-mentioned prior art, since the seed crystal is a flat substrate, a plurality of nuclei are generated simultaneously and frequently at the start of crystal growth. It was found that twins and polycrystals were likely to occur when the growth directions were different, and there was a problem that the yield of single crystals in a desired growth direction was reduced.

The present invention has been made in view of the above circumstances, and has as its object to improve the invention according to International Application No. PCT / JP95 / 02025 to improve the yield of single crystals in a desired growth direction. I do.

[0009]

In order to achieve the above object, the present invention has a melting point higher than a growth temperature of a crystal to be grown, and has a different component from the crystal to be grown.
In addition, a seed crystal having a property of low solubility in a melt or a solution containing a constituent element of a crystal to be grown as a component, and further having a seed crystal having substantially the same diameter as the crystal to be grown is brought into contact with the melt or the solution to form a melt. In growing a bulk crystal from a liquid or a solution, as a seed crystal substrate, the surface of the seed crystal substrate is not less than 2 ° with respect to a plane having a predetermined orientation and not more than half the angle at which the next lower-order plane appears. A substrate inclined by a predetermined angle is used.

FIG. 2 schematically shows a seed crystal substrate 12 in which the substrate surface is inclined by a predetermined angle θ with respect to a plane having a predetermined orientation, and the surface of the substrate 12 is microscopically shown. Are formed in a step-like manner by a step 12a of one atomic layer and a terrace 12b of a flat atomic layer. in this way,
The presence of the step 12a on the surface of the substrate 12 facilitates the generation of nuclei, and the plane orientation of the generated nuclei is considered to be affected by the substrate 12 in both the planar direction and the crystal growth direction (vertical direction). Therefore, the substrate 12
Even if nuclei occur simultaneously and multiple times on the surface, the plane orientation of each nucleus matches, the same plane is easily formed, and a single crystal grows easily.

In the present invention, the seed crystal is made of sapphire (aluminum oxide: Al ₂ O ₃ ), and the surface of the sapphire substrate is at least 2 ° and at most 30 ° with respect to the (0001) plane; 2 ° or more to the surface 30
° or less, 2 ° or more and 30 ° or less with respect to the (1-123) plane, or 2 ° or more and 45 ° or less with respect to the (11-20) plane (this specification). In the description, in the notation of the Miller index, -N (N is a natural number) indicates that the coordinate axis intersects the corresponding coordinate axis in the minus direction.
Here, the (0001) plane of the sapphire substrate, (−101)
2) It is appropriate that the inclination angle with respect to the (1-123) plane or the (11-20) plane is in the range of not less than 2 ° and not more than the above-mentioned angle. On the other hand, if the angle exceeds the above-mentioned angle with respect to each plane, a plane other than the desired orientation grows. The reason for polycrystallization when the tilt angle is less than 2 ° is that the length of the terrace 12b of the seed crystal substrate 12 (when the tilt angle is 2 °, the length of the terrace 12b is 30 angstroms (22 atomic layers)). Since the length becomes longer and the number of steps 12a per unit area decreases, the plane orientation of the nuclei simultaneously and frequently generated at a plurality of locations is not sufficiently controlled by the step 12a.
This is probably because they are not aligned in the same direction.

Further, a ZnTe single crystal, a ZnSe single crystal,
A CdTe single crystal or a CdZnTe single crystal may be grown. In that case, the seed crystal substrate is placed in a crucible, a predetermined amount of Te as a solvent, a predetermined amount of ZnTe raw material as a solute, a predetermined amount of Se as a solvent, a predetermined amount of ZnSe raw material as a solute, and a predetermined amount of solvent as a solvent. Quantitative T
e and a predetermined amount of CdTe raw material as a solute, or a predetermined amount of Te as a solvent and a predetermined amount of CdZnTe raw material as a solute, sealed in an airtight container, heated by a heater to form a solution, and the airtight container was heated to a temperature. By gradually cooling under a gradient, a ZnTe single crystal, ZnSe
A single crystal, a CdTe single crystal, or a CdZnTe single crystal may be precipitated.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a bulk crystal growth method according to the present invention will be described.

In this crystal growth method, the seed crystal has, for example, a diameter substantially the same as that of the crystal to be grown, and a surface of the seed crystal having an angle of 2 ° or more with respect to a plane having a predetermined orientation, and an angle at which the next lower-order plane appears. Using a thin-plate substrate inclined by a predetermined angle within a range of half or less, a bulk crystal is grown by, for example, the VB method as shown in FIG. 1, the VGF method as shown in FIG. 3, or the LEC method. It was made. Further, the seed crystal has a melting point higher than the growth temperature of the crystal to be grown, has a different component from the crystal to be grown, and has a low solubility in a melt or a solution containing the constituent element of the crystal to be grown as a component. It has characteristics. Here, the “angle at which the next lower-order plane appears” means that when the single crystal of the seed crystal substrate is tilted in a certain direction with respect to a plane having a predetermined orientation as a reference, the next lower-order plane is oriented in a reference direction. The angle at which it appeared. For example, in the case of sapphire (aluminum oxide: Al ₂ O ₃ ), the plane having a predetermined orientation is (00).
The angle is 60 ° for the (01), (−1012), and (1-123) planes, and is 90 ° for the (11-20) plane.

More specifically, in the case of the VB method, as shown in FIG.
The crucible 10 is filled with, for example, a compound semiconductor material to be a solute and a solvent for dissolving the material, and the crucible 10 is filled with the quartz ampoule 4 as an airtight container.
And the ampule 4 is vacuum-sealed and placed in a vertical heating furnace and heated by the heater 3. Then, when the compound semiconductor raw material and the solvent in the crucible 10 are sufficiently dissolved to obtain the solution 5, the power distribution to the heater 3 is adjusted to change the predetermined furnace temperature distribution generated from the high temperature side to the low temperature side. By gradually moving the ampoule 4 (from above to below in FIG. 1), the crystal is gradually grown from the seed crystal 12 side toward the upper side of the solution 5. In this way, a bulk single crystal of a II-VI compound semiconductor such as ZnTe can be easily obtained.

Instead of putting the compound semiconductor raw material and the solvent in the crucible 10, the compound semiconductor raw material is put in the crucible 10, and the raw material melt is heated and melted by the heater 3 to solidify the raw material melt. You may do so.

In the case of the VGF method, as shown in FIG. 3, the seed crystal substrate 12 having the above-described structure is fixed to the bottom of the crucible 10 by the pressing member 15, and the compound semiconductor raw material is put into the crucible 10. . Then, a predetermined amount of the element 14 for controlling the vapor pressure is put into the reservoir portion 4B of the quartz ampule 4, and the crucible 10 is set in the growth chamber 4A of the quartz ampule 4, and the ampule 4 is vacuum-sealed. Next, the quartz ampule 4 is set in a vertical heating furnace and heated by the heater 3. Then, when the compound semiconductor raw material in the crucible 10 is melted and the raw material melt 5 is obtained, the amount of power supply to the heater 3 is adjusted, and the temperature gradient is set such that the temperature becomes higher from the bottom of the crucible upward. 5 and gradually cooled while maintaining the temperature gradient, and solidified from the side of the seed crystal substrate 12 toward the upper part of the raw material melt 5 to grow crystals.

In the example of FIG. 3, the crucible 10 is a heat sink 1 for heat radiation extending downward from the bottom plate of the crucible body 10A.
0B. With the heat sink 10B, the heat transmitted from the raw material melt 5 via the seed crystal substrate 12 can be efficiently dissipated, and the productivity is further improved.

Instead of putting the compound semiconductor raw material in the crucible 10, the compound semiconductor raw material and the solvent are put in the crucible 10, and they are heated by the heater 3 to be sufficiently dissolved. May be precipitated. By doing so, a bulk single crystal of a II-VI compound semiconductor such as ZnTe can be obtained more easily than crystal growth from the raw material melt.

Here, the area of the seed crystal substrate 12 at the portion in contact with the raw material melt (or solution) 5 is not particularly limited, but is preferably 1 cm ² or more. The reason is that if the area of the seed crystal substrate 12 is smaller than 1 cm ² , the productivity is deteriorated. More preferably, seed crystal substrate 12 should have a size that fits exactly at the bottom of crucible 10 storing raw material melt (or solution) 5. By doing so, the shape of the bottom of the crucible 10 can be made flat, and the shape of the crucible 10 can be simplified.

Since the melting point of the seed crystal substrate 12 is higher than the crystal growth temperature and is not melted during seeding, the seed crystal substrate 12
May be thin, and is not particularly limited, but the thickness is preferably 5 mm or less, more preferably 1 mm or less. The reason is that even if the thickness is excessively increased, the economic efficiency is only deteriorated. In addition, in order to release the heat of the raw material melt (or solution) 5 while maintaining good thermal conductivity, 5 mm or less, more preferably This is because it is better to be 1 mm or less. By efficiently radiating the heat in the raw material melt (or solution) 5 to the outside using the thin seed crystal substrate 12, the growth rate can be increased and the productivity is improved.

According to each of the above embodiments, when the crystal is grown by the vertical Bridgman method or the vertical gradient freezing method, the surface of the seed crystal substrate 12 is at least 2 ° with respect to the plane having a predetermined orientation, and the next lower order. Since the substrate is tilted by a predetermined angle within a range of not more than half the angle at which the surface emerges, nucleation is likely to occur, and the seed crystal substrate 12
, The nuclei generated simultaneously and simultaneously have the same plane orientation, the same plane is easily formed, and a single crystal is easily grown. Therefore, the yield of the single crystal is improved as compared with the conventional case.

Note that a liquid-sealed Czochralski (LE)
The seed crystal substrate 12 can also be used in the C) method or the Czochralski (CZ) method.

[0024]

EXAMPLES The features of the present invention will be clarified below with reference to examples and comparative examples. The present invention is not limited by the following embodiments. Example 1 Using a heating furnace shown in FIG. 1, a ZnTe single crystal was grown by a VB method using Te as a solvent.

First, a thickness of 5 mm made of sapphire whose substrate surface is inclined by 10 ° in the M direction with respect to the (0001) plane (C plane) of sapphire is placed on the bottom of a graphite crucible.
In the following, a seed crystal substrate (sapphire substrate) having a diameter of 2 inches was placed and fixed by a holding member. Then, 480 g of Te as a solvent and 500 as a solute were placed in a crucible.
g of ZnTe polycrystalline raw material (a sufficient amount to dissolve in 480 g of Te solvent at a crystal growth temperature of 1100 ° C.)
And place the crucible in a quartz ampoule at 2 × 10 ^-6 To
Sealed in rr vacuum.

Next, the quartz ampoule is placed in a crystal growing furnace and then heated by a heater so that the temperature at the bottom of the crucible becomes 1165 ° C. and the temperature at the upper surface of the solution formed by melting the solvent and the solute becomes 1150 ° C. A temperature gradient was provided in the furnace, and the state was maintained for 2 days to sufficiently dissolve the solute. Thus, by setting the temperature of the crucible bottom higher than the temperature of the upper surface of the solution, convection occurs in the solution,
Thereby, dissolution of the solute is promoted, and the surface of the seed crystal substrate is washed by convection to become a clean surface.

Thereafter, the temperature distribution in the crystal growing furnace was changed by the heater so that the temperature was lowered by a temperature gradient of 10 ° C./cm downward in the furnace. During the temperature gradient, the quartz ampoule was moved to a low temperature side at a speed of 2 cm / day to grow crystals. The obtained crystal was a ZnTe single crystal grown in the (100) direction, and the yield of the ZnTe single crystal grown in the (100) direction was 70 to 80%. (Example 2) A sapphire substrate whose surface was inclined by 2 ° in the M direction with respect to the (0001) plane (C plane) of sapphire was used as a seed crystal substrate under the same conditions as in Example 1 above. Crystal growth was performed. The obtained crystal is (100)
The yield of the ZnTe single crystal grown in the (100) direction was 70 to 80%. (Example 3) A sapphire substrate whose surface is inclined by 30 ° in the M direction with respect to the (0001) plane (C plane) of sapphire was used as a seed crystal substrate under the same conditions as in Example 1 above. Crystal growth was performed. The obtained crystal is (10
A ZnTe single crystal grown in the (0) direction;
The yield of ZnTe single crystal grown in the direction is 70-80.
%Met. (Comparative Example 1) A sapphire substrate whose surface was inclined by 1 ° in the M direction with respect to the (0001) plane (C plane) of sapphire was used as a seed crystal substrate under the same conditions as in Example 1 above. Crystal growth was performed. Observation of the obtained crystals showed that the yield of ZnTe single crystal was 50-60%, (1
The yield of ZnTe single crystal grown in the (00) direction is 45
５５55%. In some of the ZnTe single crystals, two large grain boundaries were generated from the center of the seed crystal substrate. The cause of the generation of the grain boundary is that the terrace (see FIG. 2) of the seed crystal substrate becomes long and the ratio of the number of steps (see FIG. 2) per unit area is small. It is probable that the control of the plane orientation was not sufficient, and nuclei having two different plane directions were generated and grown. (Comparative Example 2) A sapphire substrate whose substrate surface was inclined by 40 ° in the M direction with respect to the (0001) plane (C plane) of sapphire was used as a seed crystal substrate under the same conditions as in Example 1 above. Crystal growth was performed. Although a ZnTe single crystal was obtained, its growth direction was different from the (100) direction. The yield of the ZnTe single crystal was 70-80%. Comparative Example 3 Crystal growth was performed under the same conditions as in Example 1 except that a sapphire substrate having a (0001) plane (C plane) of sapphire was used as a seed crystal substrate. Observation of the obtained crystal showed that the yield of ZnTe single crystal was 50 to 60%, and the Z
The yield of nTe single crystal was 45-55%. (Comparative Example 4) Same as Example 1 except that a sapphire substrate having a (0001) plane (C plane) of sapphire substrate surface was used as a seed crystal substrate and placed at a bottom of the crucible at an angle of 5 °. Crystal growth was performed under the conditions. Observation of the obtained crystal showed that the yield of ZnTe single crystal was 60-70.
%, But the yield of ZnTe single crystal grown in the (100) direction was 55 to 65%.

In the above embodiment, an example in which a ZnTe single crystal is grown has been described. However, the present invention is not limited to this, and the present invention is applicable to a case where a ZnSe single crystal, a CdTe single crystal, or a CdZnTe single crystal is grown. In that case, ZnSe
In the case of growing a single crystal, a predetermined amount of Se as a solvent and a predetermined amount of ZnSe raw material as a solute, and in the case of growing a CdTe single crystal, a predetermined amount of Te as a solvent and a predetermined amount of Cd as a solute.
When growing a Te raw material or a CdZnTe single crystal, a predetermined amount of Te is used as a solvent and a predetermined amount of CdZnTe is used as a solute.
It is possible to grow using raw materials.

In the above embodiment, an example of growing a single crystal by the VB method has been described. However, the VGF method, the LEC method, the CZ
It is also applicable to single crystal growth by the method.

[0030]

According to the present invention, a melt or solution having a melting point higher than the growth temperature of a crystal to be grown, a component different from that of the crystal to be grown, and containing a constituent element of the crystal to be grown as a component is used. The seed crystal having the property of low solubility and having the same diameter as the crystal to be grown is brought into contact with the melt or the solution to grow the bulk crystal from the melt or the solution. The surface of the seed crystal substrate is 2
The substrate is inclined at a predetermined angle within the range of not less than ° and half the angle at which the next lower-order plane emerges, so that nucleation is likely to occur and simultaneous occurrence occurs due to the influence of the seed crystal substrate. Since the plane orientations of the respective nuclei easily match, the same plane is easily formed, and the yield of single crystals is improved as compared with the conventional case.

Further, according to the present invention, the seed crystal is made of sapphire (aluminum oxide: Al ₂ O ₃ ), and the surface of the sapphire substrate is 2 ° with respect to the (0001) plane.
As described above, since the crystal is inclined by a predetermined angle within a range equal to or less than half of the angle at which the next lower-order plane appears, a single crystal having a desired plane orientation grows without polycrystallizing the grown crystal.

Furthermore, according to the present invention, Z
An nTe single crystal, a ZnSe single crystal, a CdTe single crystal, or a CdZnTe single crystal is obtained. At that time, in the crucible,
A seed crystal substrate is installed, and a predetermined amount of T
e, a predetermined amount of ZnTe raw material as a solute, a predetermined amount of Se as a solvent and a predetermined amount of ZnSe raw material as a solute, a predetermined amount of Te as a solvent and a predetermined amount of CdTe raw material as a solute,
A predetermined amount of Te as a solvent and a predetermined amount of CdZn as a solute
A Te raw material is charged, sealed in an airtight container, heated by a heater to form a solution, and the airtight container is gradually cooled down under a temperature gradient, whereby ZnTe single crystal, ZnSe single crystal, CdTe Single crystal or CdZn
Because a Te single crystal is deposited, ZnT
A bulk single crystal of e, ZnSe, CdTe, or CdZnTe is obtained.

[Brief description of the drawings]

FIG. 1 is a schematic view showing an example in which the present invention is applied to a vertical Bridgman method.

FIG. 2 is a partially enlarged longitudinal sectional view schematically showing a seed crystal substrate used in the crystal growth method according to the present invention.

FIG. 3 is a schematic view showing an example in which the present invention is applied to a vertical gradient freezing method.

FIG. 4 is a schematic view showing crystal growth by a conventional vertical gradient freezing method.

[Explanation of symbols]

 3 Heater 4 Airtight container (quartz ampoule) 5 Raw material melt or solution 12 Seed crystal substrate

Continued on the front page (51) Int.Cl. ⁶ Identification code FI C30B 29/50 C30B 29/50

Claims (4)

[Claims] 1. A crystal having a melting point higher than a growth temperature of a crystal to be grown, and having a component different from that of the crystal to be grown,
In addition, a seed crystal having a property of low solubility in a melt or a solution containing a constituent element of a crystal to be grown as a component, and further having a seed crystal having substantially the same diameter as the crystal to be grown is brought into contact with the melt or the solution to form a melt. In growing a bulk crystal from a liquid or a solution, as a seed crystal substrate, the surface of the seed crystal substrate is not less than 2 ° with respect to a plane having a predetermined orientation and not more than half the angle at which the next lower-order plane appears. A method for growing a bulk crystal, comprising using a substrate inclined at a predetermined angle. 2. The seed crystal is made of sapphire,
The surface of the sapphire substrate is 2 ° with respect to the (0001) plane.
Not less than 30 ° and not less than 2 ° and not more than 3 with respect to the (-1012) plane.
0 ° or less, 2 ° to 30 ° with respect to the (1-123) plane, or 2 ° to 45 ° with respect to the (11-20) plane. 2. The method of growing a bulk crystal according to claim 1, wherein -N (N is a natural number) indicates that the index intersects the corresponding coordinate axis in a negative direction in the notation of the index. 3. A ZnTe single crystal, a ZnSe single crystal, Cd
3. The method of growing a bulk crystal according to claim 1, wherein a single crystal of Te or a single crystal of CdZnTe is grown. 4. A seed crystal substrate is placed in a crucible, a predetermined amount of Te as a solvent, a predetermined amount of ZnTe as a solute, a predetermined amount of Se as a solvent, a predetermined amount of ZnSe as a solute, and a predetermined amount of solvent as a solvent. A fixed amount of Te and a predetermined amount of CdTe raw material as a solute, or a predetermined amount of Te as a solvent and a predetermined amount of CdZnTe raw material as a solvent are charged, sealed in an airtight container and heated by a heater to form a solution. 4. The method of growing a bulk crystal according to claim 3, wherein a ZnTe single crystal is precipitated from the solution by gradually cooling the solution under a temperature gradient.