JP2000313690A - Production of semiconductor single crystal and solid semiconductor raw material mass used therefore - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the inside of an apparatus and a melt in an apparatus from being contaminated and to improve the ratio of formation of single crystal by holding a semiconductor raw material mass in a solid state by a retaining means attached to a seed crystal, melting the mass, containing the melt in a container and bringing the seed crystal into contact with the melt in the container to grow a single crystal. SOLUTION: A polycrystal silicon in a small mass state is packed into a quartz crucible 6 in a storage chamber 2 of furnace member, heated and melted by a heater 4 and about 80% of the crucible 6 is charged with a melt L. A seed crystal S is held by a seed crystal retaining means 10 fixed to a wire 9 of a single crystal storage part 3. The polycrystal silicon mass M is seized by a cylindrical seizing part S2 of the seed crystal S and suspended and retained from the wire 9 through the seed crystal retaining means 10. The polycrystal silicon mass M is dropped by the wire 9, brought into contact with the silicon melt L and additionally melted. The seed crystal S is completely exposed by the melting of the polycrystal silicon mass M and the cylindrical seizing part S2 is brought into contact with the silicon melt L in a molten state and melted. Then a single crystal is grown on the seed crystal S and pulled.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a semiconductor single crystal and a solid semiconductor raw material lump used for the method. And a solid semiconductor raw material lump used in the method.

[0002]

2. Description of the Related Art In general, a method of manufacturing a semiconductor wafer involves melting a polycrystalline semiconductor raw material, bringing a seed crystal made of a single crystal into contact with the raw material melt, and growing a semiconductor single crystal from the seed crystal. Manufacturing methods are used.

For example, the Czochralski method (hereinafter referred to as CZ)
It is called the law. The method for producing an ingot-like silicon single crystal according to (1) is, as shown in FIG.
The quartz crucible 43 installed in the first furnace member storage chamber 42 is filled with polycrystalline silicon m0 as a raw material in the form of an irregular small mass, and the polycrystalline silicon m0 is heated by a heater 44 provided on the outer periphery of the quartz crucible 43. Seed crystal (seed crystal) attached to seed chuck 45 after completely heated and melted
S0 is immersed in a silicon melt, and seed crystal S0 and quartz crucible 43
Is rotated in the opposite direction to pull up the seed crystal S0 to grow the silicon single crystal Ig0.

[0004] Since polycrystalline silicon, which is a commonly used raw material, is in the form of an amorphous small lump, as shown in FIG. 10, a small lump-shaped polycrystalline silicon m to be filled in a quartz crucible 43 is used.
0 is bulky, and it is difficult to fill a large amount of quartz crucible 43 at one time. In addition, an expensive new quartz crucible 42 must be used each time a single crystal is pulled, which increases the pulling cost.

Therefore, as a measure for cost reduction, a so-called additional material charging method as shown in FIG. 11 has been proposed. This additional charging method enables the single crystal manufacturing apparatus 51 to be appropriately partitioned into a furnace member storage chamber 53 and a single crystal storage section 54 by a gate valve 52, and the gate valve 52 is opened and the single crystal manufacturing apparatus 51 is moved into the furnace member storage chamber 53 at the initial stage of pulling the single crystal. The placed quartz crucible 55 is filled (FIG. 11 (a)), and the polycrystalline silicon m0 having a small lump shape is melted to form about 80 cm of the quartz crucible 55.
% Of the silicon melt L0 (FIG. 11)
(B)) The solid rod-shaped polycrystalline silicon mass M0 is held by the silicon mass holding means 56 and lowered by using a raw material prepared separately from the silicon melt L0.
0 and additionally melted (FIG. 11 (c)), and the silicon melt L0 fills almost the entire quartz crucible 42.

On the other hand, after the polycrystalline silicon mass M0 is melted, the silicon mass holding means 56 is raised, and the complete gate valve 5 is removed.
2 is closed, and the silicon lump holding means 56 and the seed crystal holding means 57 are exchanged and mounted in the single crystal accommodating section 54 partitioned by the gate valve 52.
Is attached with a seed crystal S (FIG. 11D).

Thereafter, the gate valve 52 is opened, and the seed crystal S0 is brought into contact with the silicon melt L0 in a molten state in the quartz crucible 55, so that a single crystal having the same crystal orientation as the seed crystal S0 is provided below the seed crystal S0. Crystal Ig0 is grown (FIG. 11)
(E)), the silicon melt L0 hardly remains in the quartz crucible 55 (FIG. 11 (e)).

According to the method of manufacturing a semiconductor single crystal using the above-described single crystal manufacturing apparatus 51, the production amount of silicon single crystal per quartz crucible is smaller than that of a normal CZ method as shown in FIG. Increases.

However, in this manufacturing method, the gate valve 52 is closed at least once during the operation of the single crystal manufacturing apparatus 51 while the heater 58 and the like are energized, and the furnace member storage chamber 5 is closed.
3 and the single crystal storage unit 54 are separated, and the single crystal storage unit 54 is opened to exchange the attachment between the silicon mass device 56 and the seed crystal holding means 57. Attachment of the crystalline silicon mass M0 and attachment of the seed crystal S0 to the seed crystal holding means 57 must be performed, and the single crystal storage part 54 is exposed to the atmosphere. When the single crystal storage part 54 exposed to the atmosphere is again communicated with the furnace member storage chamber 53, dust and the like fall from the single crystal storage part 54, hinder the growth of the single crystal Ig0, and reduce the single crystallization rate (crystal defects This is a major factor in reducing the ratio of obtaining a single crystal without generation). Further, dust and the like fall from the gate valve chamber 59 due to the opening and closing of the gate valve 52.

As another cost reduction measure, FIG.
There is a so-called raw material recharging system as shown in FIG.

This recharging method uses a single crystal manufacturing apparatus 61.
Can be appropriately divided into a furnace member storage chamber 63 and a single crystal storage section 64 by a gate valve 62, and the single crystal Ig 1 is pulled up and taken out with the gate valve 62 opened, and is placed in a quartz crucible 65 arranged in the furnace member storage chamber 63. Molten silicon L1
(FIG. 12A), and then the gate valve 62
The seed crystal holding means 66 is replaced with a silicon lump holding means 67 in the single crystal accommodating section 64 partitioned by the step (FIG. 12B), and the polycrystalline silicon lump M1 is mounted on the silicon lump holding means 67. Lower the silicon melt L1
And melted to form a silicon melt L1 (FIG. 12).
(C)).

By melting the polycrystalline silicon mass M1, the silicon melt L1 fills almost the entire quartz crucible 65, and on the other hand, raises the silicon holding means 67 in which the polycrystalline silicon mass M1 no longer exists, and raises the gate valve. 62 is closed, and the silicon mass holding means 67 and the seed crystal holding means 66 are stored in the single crystal storage portion 64 partitioned by the gate valve 62.
The seed crystal S1 is mounted on the seed crystal holding means 66 (FIG. 12D).

Thereafter, the gate valve 62 is opened, and the seed crystal S1 is brought into contact with the molten polycrystalline silicon M1 in the quartz crucible 65 to grow a single crystal Ig1 on the seed crystal S1 (FIG. 12E). ).

However, even in this manufacturing method, the gate valve 62 is closed twice during the operation of the single crystal manufacturing apparatus 61 with the heater 68 and the like being energized, and the furnace member storage chamber 63 and the single crystal storage section 64 are closed. And the single crystal storage part 64 is opened, and the seed crystal holding means 66 and the silicon lump holding means 6 are opened.
7 and vice versa, the single crystal storage unit 64 is exposed to the atmosphere twice.

Therefore, this recharging method may cause the furnace member storage chamber 63 to be further polluted by falling of dust and the like as compared with the additional charging method, and may be a major factor in inhibiting the growth of the single crystal Ig0 and reducing the single crystallization rate. was there.

[0016] Further, since both the additional charging method and the recharging method require gas replacement in the pulling device, the cycle time required for one pulling is the same as that of a normal CZ.
There is a problem that it is longer than the law.

[0017]

Therefore, when the raw material semiconductor is supplied, the inside of the semiconductor single crystal manufacturing apparatus is not contaminated, the single crystallization rate can be improved, and the cycle time required for one pulling is long. There has been a demand for a method of producing a semiconductor single crystal which is not to be used and a solid semiconductor raw material mass used for the method.

The present invention has been made in view of the above-mentioned circumstances, and it is possible to supply a raw material semiconductor without contaminating a semiconductor single crystal manufacturing apparatus, improve a single crystallization rate, and require one pulling. An object of the present invention is to provide a method for manufacturing a semiconductor single crystal without increasing the cycle time and a solid semiconductor raw material mass used for the method.

[0019]

Means for Solving the Problems In order to achieve the above object, the invention of claim 1 of the present application provides a method for producing a semiconductor single crystal from a seed crystal by bringing the seed crystal into contact with a semiconductor raw material melt contained in a container. In a method of manufacturing a semiconductor single crystal to be grown,
A step of holding the solid state semiconductor raw material mass in the holding means provided on the seed crystal, and a step of melting the semiconductor raw material mass held in the holding means and housing the semiconductor material mass in the container,
A step of growing the single crystal by bringing the seed crystal into contact with the semiconductor raw material melt in the container.

[0020] The invention of claim 2 of the present application is characterized in that a step of preliminarily preliminarily preceding the step of melting the semiconductor raw material mass held by the holding means has a step of storing a semiconductor melt in a container. The gist of the present invention is a method of manufacturing a semiconductor single crystal according to claim 1.

According to a third aspect of the present invention, the step of preliminarily storing the semiconductor melt in the container is a step of melting a semiconductor raw material in the container at an early stage of the production of a semiconductor single crystal. The gist of the invention is a method of manufacturing a semiconductor single crystal according to claim 2.

In the invention according to claim 4 of the present application, the step of storing the semiconductor melt in the container in advance is a step of leaving the semiconductor raw material melt in the preceding manufacturing of the semiconductor single crystal. A gist of the invention is a method for manufacturing a semiconductor single crystal according to claim 2.

According to the invention of claim 5 of the present application, the method of manufacturing a semiconductor single crystal according to any one of claims 1 to 4, wherein the method of manufacturing a semiconductor single crystal is a Czochralski method. The gist is that there is.

In the invention of claim 6 of the present application, the solid semiconductor raw material mass is polycrystalline silicon, and the seed crystal is single crystal silicon.
13. The method for producing a semiconductor single crystal according to the above item.

According to the invention of claim 7 of the present application, the method is used for a method of manufacturing a semiconductor single crystal by the Czochralski method in which a seed crystal is brought into contact with a semiconductor raw material melt accommodated in a container to grow a semiconductor single crystal from the seed crystal. Semiconductor raw materials
The gist is a solid semiconductor raw material lump characterized in that the semiconductor raw material lump is held by holding means provided on the seed crystal.

According to the invention of claim 8 of the present application, the holding of the solid semiconductor material is performed by engaging a locking portion provided on the semiconductor material with a holding means provided on the seed crystal. A gist of the invention is a solid semiconductor raw material lump according to claim 7.

According to the ninth aspect of the present invention, the holding means provided on the seed crystal is a disk-shaped locking portion, and the locking portion provided on the solid semiconductor raw material block accommodates the seed crystal. The gist of the present invention is a solid semiconductor raw material according to claim 8, wherein the solid semiconductor raw material has an engagement groove portion and a hollow portion for accommodating the circular engagement portion of the seed crystal.

According to a tenth aspect of the present invention, the seed crystal and the solid semiconductor raw material have a columnar shape, and the gist is a solid semiconductor raw material mass according to the eighth or ninth aspect.

According to the eleventh aspect of the present invention, the diameter of the circular locking portion of the seed crystal is three to four times the diameter of the cylindrical seed crystal. The gist is that it is a solid semiconductor raw material lump.

[0030] According to the twelfth aspect of the present invention, the solid semiconductor raw material lump is polycrystalline silicon, and the seed crystal is single crystal silicon. It is a gist that the semiconductor raw material lump is used.

[0031]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a method for manufacturing a semiconductor single crystal according to the present invention will be described below with reference to the accompanying drawings.

A single crystal manufacturing apparatus used in the method for manufacturing a semiconductor single crystal according to the present invention as shown in FIG.
The single crystal pulling apparatus 1 by the Z method includes a furnace member storage chamber 2 and a single crystal storage part 3 provided above and connected to the furnace member storage chamber 2. The furnace member storage chamber 2 is provided with a container, for example, a quartz crucible 6 which is heated by the heater 4 and is housed in the graphite crucible 5, in which the raw material seed crystal body S1 is heated and melted. Graphite crucible 5
Is attached to a crucible rotation shaft 8 which penetrates the furnace body 7 and is connected to and rotated by a motor (not shown).

The single-crystal housing 3 is provided with a cylindrical seed crystal holding means 10 attached to the lower end of a wire 9 which is provided so as to be able to move up and down. Crystal S is attached.

As shown in FIGS. 2 and 3 in an enlarged manner, the seed crystal S attached to the seed crystal holding means 10 has a solid cylindrical seed crystal main body S1 and one end of the seed crystal main body S1. It is formed by provided holding means, for example, a disk-shaped circular locking portion S2.

The seed crystal S includes a solid semiconductor raw material lump,
For example, a polycrystalline silicon mass M as a raw material having a solid cylindrical shape is held, and at one end, for example, the upper end of the polycrystalline silicon mass M, a hollow storage portion in which the circular locking portion S2 is stored. M1, an engaging portion M2 connected to the storage portion M1 and engaged with the circular engaging portion S2, and an engaging groove M3 formed in the engaging portion M2 are provided.

Reference numeral 11 denotes an engaging pin which penetrates the mounting elongated hole S3 provided in the seed crystal S and holds the seed crystal S on the seed crystal holding means 10.

The diameter d1 of the circular locking portion S2 of the seed crystal S
Is 3 to 4 times the diameter d2 of the seed crystal body S1,
The thickness t1 of the circular locking portion S2 is preferably at least 20 mm, and the thickness t2 of the locking portion M2 is also at least 20 mm.
The height h1 of the storage section M1 is preferably 50 mm or more.

Therefore, as shown in FIG. 4, the polycrystalline silicon M is held by the seed crystal S when the seed crystal main body S1 penetrates the engaging groove M3 and the circular locking portion S stored in the storage portion M3.
2 is engaged with the locking portion M2.

Next, a description will be given of an additional material charging method in the method of manufacturing a semiconductor single crystal according to the present invention using the single crystal pulling apparatus 1.

FIG. 8 is a manufacturing process diagram of a semiconductor single crystal of the additional charge method. In the quartz crucible 6 installed in the furnace member storage chamber 2 of the single crystal pulling apparatus 1, polycrystalline silicon m as a raw material in a small lump is placed. The seed crystal S is attached to the seed crystal holding means 10 which is filled and further attached to the wire 9 of the single crystal storage part 3, and then the seed crystal body S1 of the seed crystal S is enlarged as shown in FIG. From the side of the engaging groove M3 to the engaging groove M3
The circular locking portion S2 is stored in the storage portion M3 while being inserted into the storage portion M3, and the circular locking portion S2 and the locking portion M2 are engaged with each other, so that the polycrystalline silicon mass M can be separated from the seed crystal S and the seed crystal holding means 10. The wire 9 is suspended from the wire 9 (FIG. 8).
(A)).

Next, the heater 4 provided on the outer periphery of the quartz crucible 6 is energized to completely heat and melt the polycrystalline silicon m.
Prior to melting of the polycrystalline silicon mass M, the silicon melt L is filled to about 80% of the quartz crucible 6 in advance (FIG. 8).
(B)). Further, the seed crystal S is prepared separately from the polycrystalline silicon m having a small lump shape, and is already stored in the single crystal storage unit 3.
The polycrystalline silicon mass M held by the circular locking portion S2 is lowered and brought into contact with the silicon melt L to be additionally melted (FIG. 8C). When the melting of the polycrystalline silicon mass M is completed, the silicon melt L fills almost the entire quartz crucible 6.

On the other hand, the polycrystalline silicon mass M is melted, and the seed crystal S is completely exposed, so that the seed crystal S can function as a seed crystal at the time of pulling (FIG. 8D). When the locking portion M2 of the polycrystalline silicon mass M is not melted and remains on the circular locking portion S2, the rotation speed of the seed crystal S is increased and centrifugal force is applied.
It is sufficient that the locking portion M2 is dropped into the silicon melt L. If the polycrystalline silicon mass M is substantially completely melted and the circular locking portion S2 of the seed crystal S is exposed, the polycrystalline silicon mass M May be attached to the seed crystal S in an unmelted state.

Thereafter, the inside of the single crystal pulling apparatus 1 is adapted to the single crystal pulling conditions, and the circular locking portion S2 of the seed crystal S is brought into contact with the silicon melt L in a molten state in the quartz crucible 6 to form a circular ring. After melting the stop S2, a single crystal Ig is grown on the seed crystal S (FIG. 8E).

Further, the single crystal ingot Ig is grown to complete the pulling, but no reusable molten silicon L remains in the quartz crucible 6 (FIG. 8E).

According to the method for manufacturing a semiconductor single crystal according to the present invention described above, the seed crystal S is used as the original seed crystal and is used as the holding means for holding the polycrystalline silicon mass M. There is no need to open the furnace body 8 or the single crystal storage unit 3 for exchanging the silicon lump holding means 10 and the silicon lump holding means, so that the polycrystalline silicon lump M can be melted as an additional material, and the quartz crucible 6 is sufficiently free from contamination. The supply of the silicon melt L becomes possible, and a large volume of silicon single crystal Ig can be pulled at a high rate at a time.

Further, a gate valve for appropriately separating the furnace member storage chamber 2 and the single crystal storage section 3 from the single crystal pulling apparatus 1 by the gate valve becomes unnecessary, and dust and the like fall from the single crystal storage section 3 as the gate valve opens and closes. As a result, the molten silicon melt L is not contaminated, the growth of the single crystal Ig is not hindered, and the single crystallization ratio can be increased.

In addition, when the initial small lump-shaped polycrystalline silicon m and the polycrystalline silicon lump M are simultaneously loaded in the pulling step, and when the pulled single crystal ingot I
Since there is no need to open the furnace body 7 or the single crystal storage unit 3 during a series of steps except for the time of taking out the g, gas replacement is also unnecessary, and the cycle time required for one pulling is also reduced by the ordinary CZ method. No longer than.

Next, a so-called recharge method, which is another embodiment of the method of manufacturing a semiconductor single crystal according to the present invention, will be described using the above-described single crystal pulling apparatus 1.

FIG. 9 shows a manufacturing process of the semiconductor single crystal of the recharge method. The pulled single crystal Ig is pulled up, and the molten silicon L is left in the quartz crucible 6 (FIG. 9).
(A)) Next, the gate valve is closed, the single crystal Ig is taken out, and the seed crystal S having the same structure as that shown in FIG. 8 used in the above-described embodiment is attached to the seed crystal holder 10. The locking portion M1 of the polycrystalline silicon mass M is engaged with the circular locking portion S2 of the seed crystal S (FIG. 9B). Thereafter, the polycrystalline silicon mass M is lowered and brought into contact with the silicon melt L stored in advance in the quartz crucible 6 to be melted, thereby forming the silicon melt L (FIG. 9C). By melting the polycrystalline silicon mass M, the silicon melt L becomes a quartz crucible 6.
Almost full of.

On the other hand, the seed crystal S after the polycrystalline silicon mass M is melted is completely exposed, and is in a state where it can function as a seed crystal at the time of pulling (FIG. 9D). Thereafter, the inside of the single crystal pulling apparatus 1 is adapted to the single crystal pulling conditions, and the circular locking portion S2 of the crystal S is brought into contact with the silicon melt L in a molten state in the quartz crucible 6, so that the seed crystal S becomes a single crystal. Ig is grown (FIG. 9E).

According to the method of manufacturing a semiconductor single crystal of this embodiment, the seed crystal S is used as the original seed crystal and is used as the holding means for holding the polycrystalline silicon mass M. The single crystal storage unit 3 needs to be opened only once in order to replace the lump holding means. Therefore, it is possible to raise the silicon single crystal Ig at a high single crystallization rate, which contributes to a reduction in the manufacturing cost of the semiconductor single crystal.

For this reason, the number of times the gate valve is opened and closed, which is at least two times in the conventional recharge method, is reduced.
It is possible to supply a sufficient amount of the silicon melt while reducing the risk of contamination in the furnace due to the opening and closing, and it is possible to pull up the silicon single crystal at a high single crystallization rate.

[0053]

EXAMPLE 1 (Additional charge method) Using the pulling apparatus shown in FIG. 8, the furnace material storage chamber 2 and the single crystal storage section 3 were opened to the atmosphere and formed into a quartz crucible having a diameter of 22 inches. 100 kg of polycrystalline silicon. Then, in this state, the single crystal storage part 3 is provided with the seed crystal provided with the holding means of the present invention, and the seed crystal holds a cylindrical polycrystalline silicon lump of 20 kg in a state where the gate valve is opened and the furnace material storage chamber and The single crystal housing was closed.

Next, after melting the polycrystalline silicon in the quartz crucible, the polycrystalline silicon held by the seed crystal was lowered and brought into contact with the silicon melt in the quartz crucible to be completely melted. Subsequently, the seed crystal was brought into contact with the silicon melt, and the portion corresponding to the holding means was melted, and then the silicon single crystal was pulled up according to a usual method. Table 1 shows the yield of the obtained dislocation-free silicon single crystal. In the present embodiment, the opening and closing of the gate valve is not performed.

Comparative Example 1 (Additional Charge Method) Using the pulling apparatus shown in FIG. 8, the furnace material storage chamber 2 and the single crystal storage section 3 were opened to the atmosphere, and a small crucible having a diameter of 22 inches was formed into a small crucible. 100 kg of polycrystalline silicon was filled. Then, the furnace material storage chamber and the single crystal storage part were closed with the gate valve opened while the columnar polycrystalline silicon lump was held in the single crystal storage part 3 via dedicated holding means in this state.

Next, after the polycrystalline silicon in the quartz crucible was melted, the polycrystalline silicon held by the exclusive holding means was lowered and brought into contact with the silicon melt in the quartz crucible to be melted.

After that, the holding means is pulled up to the single crystal accommodating portion, the gate valve is closed, and the single crystal accommodating portion is opened after separating from the furnace material accommodating portion, and the exclusive holding means is set to the silicon seed crystal for pulling the single crystal. Replaced. Then close the single crystal storage,
After the internal atmosphere was made the same as that of the furnace material storage section, the gate valve was opened, the seed crystal was lowered, and the silicon single crystal was pulled up according to a usual method.

Table 1 shows the yield of the obtained dislocation-free silicon single crystal. In this comparative example, the opening and closing of the gate valve is 1
Has been done times.

[0059]

[Table 1]

Example 2 (Recharging Method) The first silicon single crystal was pulled in the usual manner using the pulling apparatus shown in FIG. The pulled single crystal was pulled into the single crystal storage part, and the gate valve was closed and taken out.

Next, instead of the single crystal taken out, a seed crystal provided with the holding means of the present invention and 50 kg
After holding the columnar polycrystalline silicon lump and closing the single crystal storage section, making the internal atmosphere the same as the furnace material storage section, opening the gate valve, lowering the seed crystal and polycrystalline silicon lump into a quartz crucible The polycrystalline silicon mass was completely melted by contacting the remaining silicon melt. After that, the portion corresponding to the seed crystal holding means was melted, and then the silicon single crystal was pulled up according to a usual method. Table 2 shows the yield of dislocation-free silicon single crystals obtained by recharging. In this embodiment, the gate valve is opened and closed only once.

Comparative Example 2 (Recharge Method) Using the pulling apparatus shown in FIG. 9, the first silicon single crystal was pulled in a usual manner. The pulled single crystal was pulled into the single crystal storage part, and the gate valve was closed and taken out.

Then, instead of the single crystal taken out, a columnar polycrystalline silicon lump of 50 kg was held through a dedicated holding means to close the single crystal storage part, and the internal atmosphere was made the same as that of the furnace material storage part. After that, the gate valve was opened, the polycrystalline silicon mass was lowered, and was brought into contact with the silicon melt remaining in the quartz crucible to melt the polycrystalline silicon mass. Thereafter, the holding means was pulled up to the single crystal storage part, the gate valve was closed, and the single crystal storage part was opened after being isolated from the furnace material storage part, and the dedicated holding means was replaced with a silicon seed crystal for pulling the single crystal. . Thereafter, the single crystal storage section was closed, the internal atmosphere was made the same as that of the furnace material storage section, the gate valve was opened, the seed crystal was lowered, and the silicon single crystal was pulled in accordance with a usual method.

Table 2 shows the yield of dislocation-free silicon single crystals obtained by recharging. In this embodiment, the gate valve is opened and closed twice.

[0065]

[Table 2]

[0066]

According to the method for producing a semiconductor single crystal according to the present invention, the seed crystal is also used as a holding means for holding the seed crystal and the solid semiconductor raw material lump. It is possible to prevent contamination of the inside of the single crystal manufacturing apparatus and the silicon melt accompanying the supply of the raw material with the solid semiconductor raw material lump, thereby improving the single crystallization rate.

Even if the furnace body or a part of the furnace body is not opened or the number of times of opening is reduced by also using the seed crystal, a sufficient amount of silicon melt can be used for the quartz crucible using a solid semiconductor raw material mass as an additional raw material. And the replacement of gas in the furnace is not required, and the cycle time required for one pulling is not extended.

Further, if the method is applied to the additional charging method of the raw material, a silicon melt free from contamination can be sufficiently supplied to the quartz crucible, so that a large-capacity silicon single crystal having a high single crystallization rate can be pulled.

When applied to the raw material recharging method,
Since a silicon melt without contamination can be repeatedly supplied to the quartz crucible, a plurality of silicon single crystals having a high single crystallization rate can be pulled out from one quartz crucible, and the manufacturing cost can be reduced.

Further, since the solid semiconductor raw material mass is held by engaging the locking portion provided on this semiconductor raw material mass with the holding means provided on the seed crystal, the seed crystal is separated from the seed crystal and the solid material. It is also possible to use as a holding means for holding the semiconductor raw material lump, eliminating the need for replacement of the holding means, preventing contamination of the semiconductor raw material melt due to the supply of the solid semiconductor raw material lump, and improving the single crystallization rate. be able to. Further, the replacement of the gas in the furnace is not required, and the cycle time required for one pulling is not lengthened.

Further, when the locking portion provided on the seed crystal is formed in a disk shape, a semiconductor single crystal having a high single crystallization ratio can be pulled.

When the diameter of the circular locking portion of the seed crystal is set to be three to four times the diameter of the columnar seed crystal, the solid semiconductor raw material lump can be reliably held, and
A semiconductor single crystal having a high single crystallization ratio can be pulled.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram of a single crystal manufacturing apparatus used in a semiconductor single crystal manufacturing method according to the present invention.

FIG. 2 is a side view of a seed crystal incorporated in a single crystal manufacturing apparatus used in the method for manufacturing a semiconductor single crystal according to the present invention.

FIG. 3 is a plan view of the seed crystal shown in FIG. 2;

FIG. 4 is an explanatory view showing an engagement state between a seed crystal and a semiconductor raw material mass incorporated in a single crystal manufacturing apparatus used in the semiconductor single crystal manufacturing method according to the present invention.

FIG. 5 is a plan view of the semiconductor raw material block shown in FIG. 4;

FIG. 6 is a plan view of the semiconductor raw material block shown in FIG. 4;

FIG. 7 is a sectional view of the semiconductor raw material block shown in FIG. 4;

FIG. 8 is a manufacturing process diagram of one embodiment of a method for manufacturing a semiconductor single crystal according to the present invention.

FIG. 9 is a manufacturing process diagram of another embodiment of the method for manufacturing a semiconductor single crystal according to the present invention.

FIG. 10 is a conceptual diagram of a single crystal manufacturing apparatus used in a conventional semiconductor single crystal manufacturing method.

FIG. 11 is a manufacturing process diagram of a conventional method for manufacturing a semiconductor single crystal.

FIG. 12 is another manufacturing process diagram of a conventional method for manufacturing a semiconductor single crystal.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Single crystal manufacturing apparatus 2 Furnace member storage room 3 Single crystal storage part 4 Heater 5 Graphite crucible 6 Quartz crucible 7 Furnace body 8 Crucible rotation axis 9 Wire 10 Seed crystal holding means 11 Engagement pin M Semiconductor raw material lump (polycrystalline silicon lump) ) M1 storage section M2 locking section M3 engaging groove section S seed crystal S1 seed crystal main body S2 holding means (circular locking section) S3 mounting slot

[Procedure amendment]

[Submission date] June 17, 1999 (1999.6.1
7)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0002

[Correction method] Change

[Correction contents]

[0002]

2. Description of the Related Art In general, a method for producing a semiconductor wafer is to produce a semiconductor single crystal by melting a polycrystalline semiconductor raw material, bringing a single crystal into contact with a seed crystal made of the single crystal, and growing the semiconductor single crystal from the seed crystal. A method is used.

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0032

[Correction method] Change

[Correction contents]

A single crystal manufacturing apparatus used in the method for manufacturing a semiconductor single crystal according to the present invention as shown in FIG.
The single crystal pulling apparatus 1 by the Z method includes a furnace member storage chamber 2 and a single crystal storage part 3 provided above and connected to the furnace member storage chamber 2. The furnace member storage chamber 2 is provided with a container, for example, a quartz crucible 6 which is heated by the heater 4 and is housed in the graphite crucible 5, and in the quartz crucible 6, the polycrystalline silicon m as a raw material in the form of small blocks is heated and melted. You.
The graphite crucible 5 penetrates the furnace body 7 and is attached to a crucible rotating shaft 8 which is connected to and rotated by a motor (not shown).

Claims (12)

[Claims] In a method for producing a semiconductor single crystal, wherein a semiconductor single crystal is grown from the seed crystal by bringing the seed crystal into contact with the semiconductor raw material melt accommodated in the container, the holding means provided on the seed crystal has a solid state. Holding the semiconductor raw material mass, melting the semiconductor raw material mass held by the holding means and housing the semiconductor raw material mass in the container, and bringing the seed crystal into contact with the semiconductor raw material melt in the container. Growing a single crystal. 2. The method according to claim 1, further comprising a step of storing a semiconductor melt in a container in advance as a step preceding the step of melting the semiconductor raw material mass held by the holding means. The method for producing a semiconductor single crystal according to the above. 3. The method according to claim 2, wherein the step of storing the semiconductor melt in the container in advance is a step of melting a semiconductor raw material in the container at an early stage of the production of a semiconductor single crystal. Of manufacturing a semiconductor single crystal. 4. The method according to claim 1, wherein the step of storing the semiconductor melt in the container in advance is a step of retaining the semiconductor raw material melt in the preceding production of the semiconductor single crystal. Item 3. The method for producing a semiconductor single crystal according to Item 2. 5. The method for producing a semiconductor single crystal according to claim 1, wherein the method for producing a semiconductor single crystal is a Czochralski method. 6. The method for producing a semiconductor single crystal according to claim 1, wherein the solid semiconductor raw material mass is polycrystalline silicon, and the seed crystal is single crystal silicon. 7. A semiconductor raw material used in a method of manufacturing a semiconductor single crystal by a Czochralski method of growing a semiconductor single crystal from a seed crystal by bringing a seed crystal into contact with a semiconductor raw material melt contained in a container. A solid semiconductor raw material mass, wherein the semiconductor raw material mass is held by holding means provided on a seed crystal. 8. The semiconductor device according to claim 7, wherein the holding of the solid semiconductor material is performed by engaging a locking portion provided on the semiconductor material with a holding means provided on the seed crystal. 3. A solid semiconductor raw material lump according to item 1. 9. The holding means provided on the seed crystal is a disk-shaped locking portion, and the locking portion provided on the solid semiconductor raw material block is provided with an engaging groove for accommodating the seed crystal. 9. The solid semiconductor raw material mass according to claim 8, comprising a hollow portion for accommodating a circular engaging portion of the seed crystal. 10. The solid semiconductor raw material mass according to claim 8, wherein the seed crystal and the solid semiconductor raw material have a cylindrical shape. 11. The solid semiconductor raw material mass according to claim 10, wherein the diameter of the circular locking portion of the seed crystal is three to four times the diameter of the cylindrical seed crystal. 12. The solid semiconductor raw material mass according to claim 7, wherein the solid semiconductor raw material mass is polycrystalline silicon, and the seed crystal is single crystal silicon.