JP2000351690A - Silicon single crystal wafer and method for manufacturing the same - Google Patents

Abstract

(57) [Problem] To provide a method of producing a crystal in a defect-free region with high yield even when a dopant concentration in the crystal changes in growing a silicon single crystal by a CZ method. Further, the present invention provides a method for increasing the tolerance of the pulling speed V and the temperature gradient G for manufacturing a defect-free region and manufacturing crystals of the defect-free region with high yield. SOLUTION: When the pulling speed of the crystal is V and the temperature gradient on the crystal side in the crystal axis direction at the solid-liquid interface is G, the defect-free region is formed over the entire radial direction of the crystal. In the method of growing a silicon single crystal while keeping the V / G value in a predetermined range in the radial direction of the crystal, the pulling speed V and / or
Alternatively, the temperature gradient G is changed. Also, silicon, oxygen,
And pulling a silicon single crystal from a silicon melt to which elements other than nitrogen are added.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a Czochralski method (hereinafter referred to as "CZ method"), in which a ring-shaped region where oxidation-induced stacking faults occur in a thermal oxidation process disappears at the center of the wafer. Further, the present invention relates to a silicon single crystal wafer having no electrical defects and free from micro defects such as voids and dislocation clusters, and a method for manufacturing the same.

[0002]

2. Description of the Related Art As a method for producing a silicon single crystal, a CZ method for growing a crystal from a melt in a crucible while pulling the crystal is widely used. In the CZ method, for example, a single crystal manufacturing apparatus having a configuration schematically shown in FIG. 1 is used. First, polycrystalline silicon is placed as a raw material in a crucible in the figure, and the raw material is melted by a heater (generally referred to as a hot zone in the following, collectively, furnace structures such as a heater and a heat insulating material) surrounding them. A single crystal having a predetermined diameter is produced by lowering the seed crystal from above the melt in the crucible and bringing the seed crystal into contact with the surface of the melt and rotating the seed crystal while controlling the pulling speed to pull it upward. Although the melt decreases as the crystal grows, the crucible position is raised according to the weight of the pulled crystal in order to keep the position of the melt surface constant with respect to the pulling device.

The purity of polycrystalline silicon used as a raw material is generally as high as 99.9999% or more. However, in order to control the conductivity type and the specific resistance of the silicon single crystal to be produced, a dopant is intentionally used. Added. To make the crystal P-type, a Group III element such as boron acting as an acceptor is added as a dopant, and to make it N-type, a Group V element such as phosphorus or antimony is added as a dopant. In addition, quartz is generally used for the crucible in which the raw material is put. Since the quartz crucible is gradually dissolved by contact with the silicon melt, the silicon melt contains a high concentration of oxygen. Therefore, the silicon melt generally contains intentionally added dopant elements and oxygen, and some of them are taken into the crystal as the crystal grows.

[0004] The dopant in the silicon melt is taken into the crystal according to its segregation coefficient. Since the segregation coefficient of the dopant is generally smaller than 1, the dopant in the melt is concentrated as the crystal grows. The concentration of the dopant incorporated into the crystal also increases (as it goes to the lower part of the crystal) as the concentration in the melt increases with the pulling of the crystal. The dopant concentration of the product silicon wafer is
Since the range of the specific resistance is specified in the specification for each customer, a crystal part outside the range is not a product. Therefore, a change in the dopant concentration in the crystal axis direction has caused a decrease in yield. In order to solve this problem, crystal pulling is performed while silicon crystals are added to the silicon melt (continuous charging method), or crystal pulling is started after a solid layer is formed again in the melt where melting is completed. (DLCZ method) has been proposed. However, none of these methods aimed at producing a defect-free region crystal.

The specific resistance of a crystal changes depending on the dopant concentration in the crystal. However, during the cooling of the crystal,
When the transit time in a low temperature region around 50 ° C. is long, a crystal defect having a property of a donor called a thermal donor is formed, so that the specific resistance is affected. Since the thermal donor can be extinguished by the additional heat treatment at 650 ° C. or higher, the crystal after the pulling is completed includes:
A heat treatment for erasing a thermal donor (hereinafter, donor killer annealing) is performed in a state of being cut into blocks or sliced into a wafer, and the specific resistance is adjusted to a target value. The resistivity after donor killer annealing is
It is almost completely determined by the dopant concentration in the crystal.

[0006] A wafer cut from a silicon single crystal may have minute dislocation clusters or voids. The voids are detected as small pits by measuring the wafer surface with a foreign matter inspection device. These pits are COP (Crystal Orig) as pits caused by crystal defects.
inated Pits). In addition, stacking faults may occur when a wafer is subjected to thermal oxidation treatment (Oxidation-Induced Stacking Faults,
OSF). Since small defects such as dislocation clusters, COPs, and OSFs may cause device failure, it is necessary to control the type, density, and size of the defects, and many studies have been made so far. Regarding the formation mechanism of these micro defects during silicon crystal growth,
It will be described in detail below.

[0007] Voronkov pointed out for the first time the relationship between the V / G value and the type of defects in a silicon crystal in a silicon crystal grown by the floating zone (FZ) method, and the same applies to a silicon crystal grown by the CZ method. (VVVoronkov; Journal of Crystal Gro
wth, 1982, Vol.59, p.625-643). Here, V indicates the growth rate of the silicon single crystal, and G indicates the temperature gradient on the crystal side in the crystal axis direction at the crystal growth interface. Also, FZ
The method is a method of obtaining a single crystal by dissolving a rod-shaped polycrystalline silicon by high-frequency heating and bringing a seed crystal into contact with the melted silicon melt and moving it later. CZ
The major difference from the FZ method is that the FZ method does not require a quartz crucible unlike the CZ method because the silicon melt is supported by the surface tension of the melt itself. Therefore, FZ
The oxygen concentration in the silicon single crystal grown by the method
It is very low as compared with the oxygen concentration in the silicon single crystal grown by the Z method.

According to this document, when the V / G value is small, an A defect and a B defect which are interstitial silicon type defects exist in a silicon single crystal. As the V / G value is increased and exceeds _a certain critical value ξa, the A defect does not exist and only the B defect remains. Further increase the V / G value.
Beyond _b , there is no B defect, and the region becomes a defect-free region. Further exceeds increased to xi] _d the V / G value, D defects in place of the defect of interstitial silicon type atomic vacancy is formed. In other words, the resulting crystals of a defect-free region be maintained between the V / G ξ _b ~ξ _d has been verified. In the proposed defect formation model, point defects (interstitial silicon and atomic vacancies) introduced from the crystal growth interface cause diffusion and recombination near the crystal growth interface. Finally, a large number of point defect species remaining in the crystal are determined by A and B described above.
That is, a defect or a D defect is formed. This V /
The relationship between the G value and the type of point defects appearing in the silicon single crystal is C
This document suggests that the present invention can be applied to a silicon single crystal grown by the Z method.

The relationship between the defect type in the silicon single crystal and the growth conditions in the CZ method has been considered as follows, like the V / G model in the FZ method proposed by Voronkov.

The predominant point defect species and its concentration in the high temperature region immediately after solidification of the crystal are determined by the ratio of the pulling rate V to the temperature gradient G in the direction of the crystal axis on the crystal side at the solid-liquid interface, V / G
2 has a relationship shown in FIG. That is, when the V / G value is large, the predominant point defect species are atomic vacancies and V / G
The atomic vacancy concentration decreases as the G value decreases, and becomes 0 at a certain value. As the V / G value is further reduced, the predominant type of point defect becomes interstitial silicon, and the concentration increases as the V / G value decreases.

It is considered that the point defects that have become dominant at a high temperature change into various structural defects depending on the concentration during the process of cooling the crystal. When V / G value is smaller than the eta ₁ is interstitial silicon present in high concentrations to form a dislocation cluster. When the V / G value is in the range from η ₁ to η ₂ , interstitial silicon is slightly present in the crystal, but since the concentration is low, no remarkable structural defect is formed. At η ₂ , both the interstitial silicon concentration and the atomic vacancy concentration are zero. In eta ₂ or more, prevalent point defect type is replacing the interstitial silicon vacancies, in the range from eta ₂ to eta _3, atomic vacancy existing in a low concentration becomes generating nuclei of oxygen precipitates Small defects (hereinafter referred to as oxygen precipitation nuclei) are formed. In the range from η ₃ to η ₄ , OSF nuclei (hereinafter referred to as OSF nuclei).
The nuclei of the OSF distributed in a ring shape), and above η ₄ , the vacancies present in high concentration form voids.

[0012] Among these structural defects, dislocation clusters have been found to deteriorate device characteristics by themselves. The slight presence of interstitial silicon does not affect device characteristics. Since the oxygen precipitate nuclei are very minute defects, they do not themselves cause deterioration of device characteristics, but rather have an effect of acting as a generation center of oxygen precipitates acting as an absorption source of harmful impurities.
The substance of the OSF nucleus is presumed to be a plate-like oxygen precipitate,
In some cases, the device itself may cause deterioration of device characteristics.
It has also been found that when OSF is generated in the device active region on the wafer surface with the OSF nucleus as the generation center by thermal oxidation, the device characteristics are significantly deteriorated. Further, it is known that voids appear as pits (COP) on the wafer surface, and that when the size exceeds a certain size, device characteristics deteriorate.

It is believed that if the V / G value is in the range from η ₁ to η ₃ , no defect that adversely affects device characteristics is formed, and the crystal region grown under this condition range has no defect. It is called an area.

On the other hand, various defects including a ring-shaped distribution of OSF are concentrically distributed on a wafer cut from a crystal grown under general conditions. FIG. 3 shows a schematic diagram of such a defect distribution. From the outermost periphery of the wafer, a dislocation cluster region, an interstitial silicon-type defect-free region, an atomic vacancy-type defect-free region, an OSF ring region, and a void region at the center. Until now, V / G value is η
_Since crystal growth has been performed under conditions close to ₃ , it is considered that the defect distribution as shown in FIG. 3 has been achieved across various values from η ₁ to η _{4 over the} entire surface of the wafer.

[0015] Voronkov proposed C using V / G as an index.
Regarding the defect control method in the Z method, see JP-A-8-330.
No. 316, a silicon single crystal wafer grown by the CZ method, a low-speed grown wafer in which an OSF generated in a ring shape when subjected to a thermal oxidation treatment disappears at the center of the wafer, and the entire surface of the wafer. A method for manufacturing a silicon single crystal wafer from which dislocation clusters are eliminated is disclosed. In this manufacturing method, when growing a silicon single crystal by the CZ method, the pulling speed is set to V (mm / min),
The average value of the temperature gradient on the crystal side in the crystal axis direction in the temperature range from the silicon melting point to 1300 ° C. is G (° C./mm).
, The V / G value is 3 from the center of the crystal and the outer periphery of the crystal.
0.20 to 0.22 mm ² between positions up to 0 mm
/ ° C./minute, and between 0.20 and 0.22 mm ² / ° C./minute between the position from the outer periphery of the crystal to 30 mm and the outer peripheral position of the crystal, or gradually increasing toward the outer periphery of the crystal. I do.

That is, the above-mentioned Japanese Patent Application Laid-Open No. 8-330316 discloses a method for producing a crystal in which a defect-free region between an OSF ring region and a dislocation cluster region is expanded in the entire radial direction.

A specific V / G control method for obtaining a defect-free region over the entire surface of a wafer is disclosed in, for example, Japanese Patent Application Laid-Open No. H10-265294. Is controlled to make V / G uniform in the crystal plane by making the temperature gradient G in the crystal axis direction on the crystal side uniform in the crystal plane.

On the other hand, only a few reports have been made on the influence of elements other than silicon introduced into the silicon crystal on the conditions for forming the defect-free region. Proceedings of the 46th Lecture Meeting on Applied Physics, p.471, 29a-Z
B-9 shows that the addition of nitrogen to the silicon crystal increases the V / G tolerance of the defect-free region, and the quality of the defect-free region when nitrogen is added is COP. It is shown that the oxide film and the breakdown voltage of the oxide film are as good as the epi-wafer. However, it is known that nitrogen in a silicon crystal acts as an OSF nucleus even if it exists in a very small amount. Also, as the device structure becomes finer, the device process tends to lower the temperature.However, the diffusion coefficient of nitrogen in the silicon crystal is large. There is a concern that segregation on the surface of a wafer that becomes a device active may cause structural defects such as OSF.

There has been no report on the effect of elements other than nitrogen on the defect-free region, and no report on the effect of the dopant concentration.

With respect to a method of pulling a silicon single crystal while applying a magnetic field to a silicon melt, reports have been made on a cusp magnetic field and a horizontal magnetic field. A cusp magnetic field device is a device in which coaxial opposed magnets are arranged above and below the outer wall of a lifting device, as shown in, for example, Japanese Patent Publication No. 2-12920. Is formed. What is a horizontal magnetic field device?
As shown in JP-B-58-50951, coaxial opposed magnets are arranged on the left and right sides of the outer wall of the lifting device, and a horizontal magnetic field is formed in the melt by the magnets. FIG. 4 schematically shows a pulling furnace in which a horizontal magnetic field device is arranged.

The method of pulling a silicon single crystal while applying a cusp magnetic field or a horizontal magnetic field to the melt has been performed for the purpose of controlling the oxygen concentration and the flow of the melt. However, there have been no reports aimed at obtaining a defect-free region.

[0022]

SUMMARY OF THE INVENTION In order to obtain a wafer which is a defect-free region (crystal having no defect region) over the entire surface of the wafer, Japanese Patent Application Laid-Open Nos.
In the method described in JP-A-265294,
As shown in FIG. 8, although a defect-free region crystal is obtained for a small length of the entire length of the ingot, most of the ingot axis direction is a dislocation cluster region or an OSF ring and a void region. In reality, the yield of crystal extraction was extremely low.

Further, although a specific defect type wafer can be formed over a certain length in the axial direction of a crystal by adopting a specific pulling condition in a specific type, a defect free defect can be produced even in the other type even if the same pulling condition is adopted. In some cases, no area wafer was obtained.

An object of the present invention is to provide a method in which a crystal of a defect-free region can be produced with a high yield in growing a silicon single crystal by the CZ method, and a crystal of a defect-free region can be produced in a different kind similarly. is there.

It is another object of the present invention to provide a method of manufacturing a crystal in a defect-free region with a high yield by increasing the tolerance of a pulling speed V and a temperature gradient G for manufacturing a defect-free region.

[0026]

In order to achieve the above object, the present invention provides: (1) In producing a silicon single crystal by the Czochralski method, the pulling speed of the crystal is V, and the crystal at the solid-liquid interface is Assuming that the temperature gradient on the crystal side in the axial direction is G, a region where ring-shaped oxidation-induced stacking faults are generated at the time of thermal oxidation treatment disappears at the center of the wafer and a defect-free region having no dislocation cluster is the radius of the crystal. In the method of growing a silicon single crystal while keeping the V / G value at the solid-liquid interface within a predetermined range in the radial direction of the crystal in order to form the silicon single crystal in all directions, the pulling speed V is adjusted in accordance with the change in the dopant concentration. And / or changing the temperature gradient (G). (2) In producing a silicon single crystal by the Czochralski method, when a crystal pulling speed is V and a temperature gradient on a crystal side in a crystal axis direction at a solid-liquid interface is G, a thermal oxidation treatment is performed. The V / G value at the solid-liquid interface is determined by calculating the radius of the crystal in order to form a ring-shaped region where oxidation-induced stacking faults disappear at the center of the wafer and to form a defect-free region without dislocation clusters in the entire radial direction of the crystal. A method for growing a silicon single crystal while keeping the silicon single crystal within a predetermined range in the pulling direction, wherein the pulling speed V and / or the temperature gradient G are controlled in accordance with a change in the dopant concentration in the crystal axis direction. A method for producing a crystal wafer. (3) V is increased as the dopant concentration is lower;
3. The method for producing a silicon single crystal wafer according to claim 1, wherein G is reduced. (4) In producing a silicon single crystal by the Czochralski method, when a crystal pulling speed is V and a temperature gradient on a crystal side in a crystal axis direction at a solid-liquid interface is G, a thermal oxidation treatment is performed. The V / G value at the solid-liquid interface is determined by calculating the radius of the crystal in order to form a ring-shaped region where oxidation-induced stacking faults disappear at the center of the wafer and to form a defect-free region without dislocation clusters in the entire radial direction of the crystal. A method for producing a silicon single crystal wafer, wherein a target V / G value is changed according to a change in a dopant concentration in a method for growing a silicon single crystal while keeping a predetermined range in a direction. (5) In producing a silicon single crystal by the Czochralski method, when the crystal pulling speed is V and the temperature gradient on the crystal side in the crystal axis direction at the solid-liquid interface is G, The V / G value at the solid-liquid interface is determined by calculating the radius of the crystal in order to form a ring-shaped region where oxidation-induced stacking faults disappear at the center of the wafer and to form a defect-free region without dislocation clusters in the entire radial direction of the crystal. 1. A method for producing a silicon single crystal wafer, wherein a V / G value is controlled in accordance with a change in a dopant concentration in a crystal axis direction in a method for growing a silicon single crystal while keeping a predetermined range in a direction. (6) The method for manufacturing a silicon single crystal wafer according to (4) or (5), wherein the lower the dopant concentration, the higher the V / G value. (7) In producing a silicon single crystal by the Czochralski method, when a crystal pulling speed is V, and a temperature gradient on a crystal side in a crystal axis direction at a solid-liquid interface is G, a thermal oxidation treatment is performed. The V / G value at the solid-liquid interface is determined by calculating the radius of the crystal in order to form a ring-shaped region where oxidation-induced stacking faults disappear at the center of the wafer and to form a defect-free region without dislocation clusters in the entire radial direction of the crystal. A method for growing a silicon single crystal while keeping a predetermined range in the direction, wherein the in-plane distribution of the temperature gradient G is controlled in accordance with the fluctuation of the dopant concentration in the crystal radial direction. Method. (8) In producing a silicon single crystal by the Czochralski method, when the crystal pulling speed is V and the temperature gradient on the crystal side in the crystal axis direction at the solid-liquid interface is G, the thermal oxidation treatment is performed. The V / G value at the solid-liquid interface is determined by calculating the radius of the crystal in order to form a ring-shaped region where oxidation-induced stacking faults disappear at the center of the wafer and to form a defect-free region without dislocation clusters in the entire radial direction of the crystal. A method for growing a silicon single crystal while keeping the silicon single crystal within a predetermined range in the direction, wherein the in-plane distribution of the V / G value is controlled in accordance with the fluctuation of the dopant concentration in the crystal radial direction. Production method. (9) In producing a silicon single crystal by the Czochralski method, when the crystal pulling speed is V and the temperature gradient on the crystal side in the crystal axis direction at the solid-liquid interface is G, the thermal oxidation treatment is performed. The V / G value at the solid-liquid interface is determined by calculating the radius of the crystal in order to form a ring-shaped region where oxidation-induced stacking faults disappear at the center of the wafer and to form a defect-free region without dislocation clusters in the entire radial direction of the crystal. A method for growing a silicon single crystal, wherein the silicon single crystal is grown while controlling the dopant concentration in the silicon melt while keeping the silicon single crystal within a predetermined range in the direction. (10) The silicon single crystal is pulled up while the silicon crystal is additionally added to the silicon melt.
The method for producing a silicon single crystal wafer according to the above. (11) Forming a solid layer in advance in the silicon melt,
10. The method for producing a silicon single crystal wafer according to claim 9, wherein the silicon single crystal is pulled while dissolving the solid layer. (12) The silicon single crystal wafer according to any one of claims 1 to 11, wherein the dopant is one or more of boron, phosphorus, aluminum, gallium, arsenic, indium, and antimony. Manufacturing method. It is.

According to these methods, (13) a silicon single crystal wafer manufactured by the Czochralski method, in which a region in which oxidation-induced stacking faults occur in a ring shape upon thermal oxidation treatment disappears at the center of the wafer. A silicon single crystal wafer, characterized in that the wafer has no dislocation clusters over the entire surface of the wafer and is doped with at least two of boron, phosphorus, aluminum, gallium, arsenic, indium and antimony. (14) A silicon single crystal wafer manufactured by the Czochralski method, in which a region in which oxidation-induced stacking faults occur in a ring shape when subjected to a thermal oxidation treatment has disappeared at the center of the wafer, and the entire surface of the wafer. A silicon single crystal wafer characterized by having no dislocation clusters over the entire surface and a variation in dopant concentration in the wafer plane of less than 5%. (15) The silicon single crystal wafer according to (14), wherein the dopant is one or more of boron, phosphorus, aluminum, gallium, arsenic, indium, and antimony. Can be obtained.

(16) In producing a silicon single crystal by the Czochralski method, when the pulling speed of the crystal is V and the temperature gradient on the crystal side in the crystal axis direction at the solid-liquid interface is G, Since the region in which oxidation-induced stacking faults occur in a ring shape during the oxidation treatment disappears at the center of the wafer and a defect-free region without dislocation clusters is formed over the entire radial direction of the crystal, V / G at the solid-liquid interface is required. In a method of growing a silicon single crystal while keeping the value within a predetermined range in the radial direction of the crystal, a method of growing silicon single crystal by adding elements other than silicon, oxygen, boron, phosphorus, aluminum, gallium, arsenic, indium, antimony, and nitrogen. A method for producing a silicon single crystal wafer, comprising pulling a silicon single crystal from a liquid. (17) In producing a silicon single crystal by the Czochralski method, when the crystal pulling speed is V and the temperature gradient on the crystal side in the crystal axis direction at the solid-liquid interface is G, The V / G value at the solid-liquid interface is determined by calculating the radius of the crystal in order to form a ring-shaped region where oxidation-induced stacking faults disappear at the center of the wafer and to form a defect-free region without dislocation clusters in the entire radial direction of the crystal. In the method of growing a silicon single crystal while keeping the silicon single crystal within a predetermined range in the direction, the silicon single crystal is added while adding elements other than silicon, oxygen, boron, phosphorus, aluminum, gallium, arsenic, indium, antimony, and nitrogen to the silicon melt. A method for producing a silicon single crystal wafer, comprising pulling a crystal. (18) The additional element is one of hydrogen, helium, carbon, neon, germanium, krypton, tin, and xenon.
2. The method according to claim 1, wherein the species is at least two species.
18. The method for producing a silicon single crystal wafer according to items 6 and 17. It is.

According to these methods, (19) a silicon single crystal wafer produced by the Czochralski method, in which a ring-shaped region where oxidation-induced stacking faults occur in the thermal oxidation treatment disappears at the center of the wafer. Wafer, and there are no dislocation clusters over the entire surface of the wafer, and hydrogen, helium, carbon,
A silicon single crystal wafer characterized in that one or more of neon, germanium, krypton, tin, and xenon are doped. Can be obtained.

(20) The silicon single crystal is pulled up while applying a magnetic field to the silicon melt.
19. The method for producing a silicon single crystal wafer according to 18. (21) The method for manufacturing a silicon single crystal wafer according to claim 20, wherein the applied magnetic field is a horizontal magnetic field or a cusp magnetic field. It is.

[0031]

BEST MODE FOR CARRYING OUT THE INVENTION The present inventors conducted two-level tests with different amounts of dopant to be added in producing a defect-free region crystal. At that time, the crystal was pulled under the conditions for manufacturing a conventionally known defect-free region crystal in which the V / G value at the solid-liquid interface was within a predetermined range in the radial direction of the crystal. Specifically, the method is described in JP-A-8-330316 or JP-A-10-265294. Except that the amount of the dopant was changed, the conditions were exactly the same at both levels. FIGS. 8 and 10 show defect region distributions of crystals having different dopant amounts. In addition, a change in the crystal axis direction of the specific resistance at the crystal center position after the donor killer annealing is also shown. The specific resistance of the crystal of FIG. 8 is 12 to 8 Ω · cm, and the specific resistance of the crystal of FIG.
１１11 Ω · cm. Although the pulling conditions are completely the same, the defect region distributions of the two are greatly different. In the crystal of FIG. 8, a defect-free region crystal is formed entirely in a crystal straight body of 300 mm to 600 mm, whereas the crystal of FIG. Dislocation clusters are formed over the entire length of the body. This result indicates that the condition range of the defect-free region depends on the dopant concentration.

The present inventors further conducted tests by changing the crystal pulling conditions variously, and investigated the relationship between the defect-free region and the dopant concentration. FIG. 5 shows the relationship between the condition range of the defect-free region, the resistivity after donor killer annealing, and the pulling rate when boron is added as a dopant. The dopant concentration in the crystal can be known from the specific resistance after the donor killer annealing, and the lower the specific resistance, the higher the dopant concentration. FIG. 5 shows that the lower the resistivity, that is, the higher the dopant concentration, the wider the tolerance of the pulling speed for the defect-free region. This result indicates that the relationship between the V / G value and the point defect type / concentration shown in FIG.
FIG. 6 shows that it changes as shown in FIG. 6 depending on the dopant concentration. That is, the values of η ₁ to η ₄ shown in FIG. 2 are not constant, but change depending on the dopant concentration.

The reason why such a phenomenon occurs is considered as follows. The dopant is incorporated into the crystal from the melt as the crystal solidifies, but the point defects (interstitial silicon,
Atomic vacancies are also generated in the crystal at a thermal equilibrium concentration as the crystal solidifies. The dominant species of point defects and their concentration are determined through processes such as diffusion of point defects generated during the cooling process of the crystal and annihilation of the pair of interstitial silicon and atomic vacancies. It is presumed that they interact with each other to change the equilibrium concentration of the point defect itself, or change the diffusion and the annihilation reaction.

Based on these findings, the present inventors have found that, when manufacturing a defect-free region crystal by changing the dopant concentration, the V / G value is adjusted by changing V and / or G for each dopant concentration. It was found that it was necessary to make.

In order to manufacture a defect-free region with high yield in the crystal axis direction, the present inventors have proposed that V and / or G be adjusted in accordance with the change in the dopant concentration in the crystal in the crystal axis direction.
It has been found that it is effective to continuously change the V / G value so as to continuously fall within an appropriate range.

Also, the shape of the solid-liquid interface during the growth of the silicon single crystal is not completely flat, but is convex upward or downward, or M-shaped or W-shaped, so that it is perpendicular to the crystal axis. The dopant concentration in the radial direction of the wafer to be sliced varies depending on the interface shape. In order to grow a defect-free crystal, it is preferable that the in-plane distribution of G be changed in accordance with the change in the dopant concentration in the radial direction. Has been found to be more effective than reducing the in-plane variation.

On the other hand, if the fluctuation of the dopant concentration in the radial direction is less than 5%, it is not necessary to particularly optimize the in-plane distribution of the V / G value, which is desirable. As a method for controlling the fluctuation of the dopant concentration in the radial direction, it is effective to perform crystal pulling while applying a magnetic field to the melt. As a magnetic field to be applied, a cusp magnetic field or a transverse magnetic field is effective.

In order to manufacture a defect-free region with high yield in the crystal axis direction, it is effective that the fluctuation of the dopant concentration in the melt accompanying the crystal pulling is suppressed as much as possible. I found something. As a method of suppressing the fluctuation of the dopant concentration in the melt, a method of pulling a crystal while additionally adding a silicon crystal to the melt or forming a solid layer in advance in the melt and dissolving the solid layer A method of pulling a crystal is effective.

The methods described so far include boron, phosphorus,
It works effectively when any one of aluminum, gallium, arsenic, indium and antimony is added as a dopant. When two or more of these dopants are added, the tolerance of the defect-free region condition can be widened while satisfying the specific resistance specification range, which is more effective.

The present inventors further investigated changes in the manufacturing conditions of the defect-free region when an element other than the dopant was added to the silicon melt. As a result, it has been found that, when hydrogen, helium, carbon, neon, germanium, krypton, tin, or xenon is added, the manufacturing conditions of the defect-free region change, and the tolerance of the defect-free region condition can be widened. These elements may be added by starting the crucible together with the silicon polycrystalline raw material in advance. Further, it is more preferable to additionally add a silicon crystal to the melt along with the pulling of the silicon crystal because a change in the concentration of the element in the melt can be suppressed. Although one type of element to be added is effective, the effect can be obtained with two or more types.

As in the case of controlling the concentration distribution of the dopant, the present inventors control the radial distribution of the crystal of the added element by pulling up the crystal while applying a magnetic field to the melt. Was found to be effective. As the applied magnetic field, a cusp magnetic field or a horizontal magnetic field is effective.

As described above, the OSF ring region is generated in the wafer surface in a certain pulling speed range, and in the pulling speed range, the diameter of the OSF ring region increases as the pulling speed increases. The lower the pulling speed, the smaller the diameter of the OSF ring region. If the pulling speed is further reduced, the OSF ring region behaves as if it disappeared at the center of the wafer. Therefore, by elucidating the behavior of the pulling speed and the change in the size of the OSF ring region, it is possible to manufacture a wafer in which the ring-shaped region in which oxidation-induced stacking faults occur at the center of the wafer during the thermal oxidation treatment of the present invention. It is possible to Also, O
In a wafer where the SF ring region has disappeared on the outer periphery of the wafer, the entire surface of the wafer is a void region. Therefore, if a defect-free region or a dislocation cluster region is generated in the wafer surface, it is clear that the OSF ring region has disappeared at the center of the wafer.

[0043]

EXAMPLES In the following comparative examples and examples, a silicon single crystal manufacturing apparatus 20 by the CZ method shown in FIG. 4 was used.

The silicon single crystal manufacturing apparatus 20 has a member for dissolving silicon, a mechanism for pulling up silicon crystal, and the like. The member for dissolving silicon is accommodated in the heating chamber 2a, Are provided inside and outside the pulling chamber 2b. Further, an intermediate chamber 2c is provided between the heating chamber 2a and the pulling chamber 2b.

A crucible 3 for accommodating dissolved silicon L is provided in the heating chamber 2a.
Is supported by a drive device (not shown) by a rotating shaft 5 so as to be rotatable and vertically movable. The driving device raises the crucible 3 by an amount corresponding to the lowering of the liquid level in order to compensate for the lowering of the liquid level accompanying the pulling of the silicon single crystal S, and rotates the crucible 3 by a predetermined rotation to stir the silicon melt L. Rotate by number. The rotating shaft passes through the heating chamber 2a, but is held by a special bearing (not shown) in order to maintain airtightness inside and outside the chamber 2 and to be used under extremely poor temperature conditions.

The crucible 3 comprises a quartz crucible 3a as in the prior art and a graphite crucible 3b for protecting the same.

On the side wall portion of the crucible 3, a heater 4 for dissolving silicon is arranged so as to surround the periphery thereof. Outside the heater 4, a heat insulating material 12 for preventing heat from the heater from being directly radiated to the heating chamber 2a is provided so as to surround the heater. The heater 4 and the heat insulating material 12
Is attached to the support 16. The support 16 is made of a material having a very high thermal resistivity.

One end of the pulling chamber 2b is attached to the wire winder 11, and the pulling wire 8 is suspended from the top wall of the ceiling 6a of the intermediate chamber 2c.
A seed crystal 9 is provided at the lower end of the pulling wire 8.
Is attached. The wire winder 11 pulls up the silicon single crystal S that gradually grows on the lower end side of the seed crystal 9 according to its growth speed and the like, and at the same time, constantly rotates the crucible 3 in the direction opposite to the rotation direction.

Argon gas is introduced from a gas inlet 13 formed in the housing portion of the pulling chamber 2b. The argon gas is discharged from a gas outlet 14 after flowing into the heating chamber 2a. I have. As described above, the argon gas is circulated in the chamber 2 because the SiO gas and the CO gas generated in the chamber 2 as the silicon is melted by the heating of the heater 4 are introduced into the silicon melt. This is to prevent mixing.

A single or double funnel made of carbon or Mo is provided above the surface of the melt. In the case of a double-layer structure, a heat insulating material may be loaded between the overlapping portions. In the following comparative examples and examples, a carbon-made funnel having a double structure and a heat insulating material interposed therebetween was used.

Using such a pulling apparatus, a silicon single crystal was pulled.

The determination of the OSF ring area was performed by cutting a wafer cut out of a crystal and mirror-finished in a steam atmosphere for 1100 hours.
After performing an oxidizing heat treatment at 1 ° C. for 1 hour, removing the oxide film on the surface with hydrofluoric acid, immersing in a light etching solution for 2 minutes to make crystal defects appear as etch pits, This was done by evaluating the distribution and density. To determine the dislocation cluster region, a wafer cut out of the crystal and mirror-finished is immersed in a Seco etching solution for 20 minutes without heat treatment, and crystal defects (dislocation loops) are revealed as etch pits. The evaluation was performed by evaluating the distribution and density. Further, the determination of the void area is performed by the foreign matter inspection device LS6000 using the COP.
Was measured.

The manufacturing conditions of the crystals common to the comparative example and the example are shown below.・ Crystal diameter: 208mm ・ Crystal straight body length: 800mm ・ Crucible diameter: 22 inches ・ Polycrystalline silicon raw material charge weight: 95kg ・ Inner diameter of lower funnel: 260mm ・ Distance from lower funnel to melt surface: 50mm ・ Crucible rotation : 4 rpm ・ Horizontal magnetic field applied: Yes ・ Magnetic field strength at crucible wall: 3000 Gauss The in-plane variation (ΔG) of G is the positional relationship between the funnel and the melt surface, specifically, the distance from the lower end of the funnel to the melt surface. Strongly depends on the conditions. As described above, if the distance from the lower end of the funnel to the melt surface is 50 mm, ΔG is 10
%, And the value of G in the longitudinal direction of the ingot is kept constant. As a result, in each of the following comparative examples and examples, the V / G value at the solid-liquid interface was 1 in the radial direction of the crystal.
A silicon single crystal can be grown while keeping the content within the range of 0% or less.

Comparative Example 1 A silicon single crystal was grown under the following conditions. -Dopant type: boron-Addition method of dopant: added into crucible together with polycrystalline silicon material before dissolution starts-Pulling rate: 0.52 mm / min

A wafer was cut out from the crystal at intervals of 50 mm, and the specific resistance and defect distribution were examined. FIG. 7 shows the defect distribution and the change in the specific resistance of the crystal center in the crystal axis direction. The specific resistance was 12 to 8 Ω · cm. Crystal straight body 0-20
At 0 mm, there is a dislocation cluster, 200-700 m
m, an OSF ring region is formed, and the diameter of the OSF ring region increases toward the lower part of the crystal, and
In mm, the OSF ring region disappeared on the outer peripheral portion of the crystal, and a COP (void) was present on the entire surface of the crystal.

Incidentally, since the crystal straight body of 0 to 200 mm has no crystals above, it is easier to cool than other parts.
The temperature gradient G tends to be larger than other parts.

<Comparative Example 2> A silicon single crystal was grown under the following conditions. -Dopant type: boron-Doping method of dopant: added into crucible together with polycrystalline silicon material before dissolution starts-Pulling rate: 0.50 mm / min

A wafer was cut out from the crystal at intervals of 50 mm, and the specific resistance and defect distribution were examined. FIG. 8 shows the defect distribution and the change in the specific resistance of the crystal center in the crystal axis direction. The specific resistance was 12 to 8 Ω · cm. Crystal straight body 0-30
At 0 mm, there is a dislocation cluster, 300-600 m
m, a defect-free region is formed, and 600 to 800 m
m, an OSF ring region is formed, and O
The diameter of the SF ring region was widened.

Comparative Example 3 A silicon single crystal was grown under the following conditions. -Dopant type: boron-Doping method of dopant: added into crucible together with polycrystalline silicon material before dissolution starts-Pulling rate: 0.48 mm / min

Wafers were cut out from the crystal at intervals of 50 mm, and the specific resistance and defect distribution were examined. FIG. 9 shows the defect distribution and the change in the specific resistance of the crystal center in the crystal axis direction. The specific resistance was 12 to 8 Ω · cm. Dislocation clusters existed over the entire length of the crystal shell.

Comparative Example 4 A silicon single crystal was grown under the following conditions. -Dopant type: boron-Doping method of dopant: added into crucible together with polycrystalline silicon material before dissolution starts-Pulling rate: 0.50 mm / min

Wafers were cut out from the crystal at intervals of 50 mm, and the specific resistance and defect distribution were examined. FIG. 10 shows the defect distribution and the change in the specific resistance of the crystal center in the crystal axis direction.
The specific resistance was 16 to 11 Ω · cm. Dislocation clusters existed over the entire length of the crystal shell.

It can be seen that the defect distribution is significantly different due to the difference in the dopant concentration in the crystal, even though the pulling conditions are exactly the same as in Comparative Example 2.

Example 1 A silicon single crystal was grown under the following conditions. -Dopant type: boron-Doping method of dopant: added into crucible together with polycrystalline silicon material before dissolution starts-Pulling rate: 0.52 mm / min

A wafer was cut out from the crystal at intervals of 50 mm, and the specific resistance and defect distribution were examined. FIG. 11 shows the defect distribution and the change in the specific resistance of the crystal center in the crystal axis direction.
The specific resistance was 16 to 11 Ω · cm. Crystal straight body 0
At 300 mm, dislocation clusters exist, and 300 to 60
At 0 mm, a defect-free area is formed, and 600 to 80
At 0 mm, an OSF ring region was formed, and the diameter of the OSF ring region increased toward the bottom of the crystal. Despite being a product having a high specific resistance and a narrow tolerance for defect-free crystal production conditions, a defect-free crystal region could be generated over 300 mm in the ingot axis direction.

In the case of a crystal having a specific resistance of 12 to 8 Ω · cm, a defect-free region crystal could be produced over a crystal axis direction of 300 mm by setting the pulling rate to 0.50 mm / min as in Comparative Example 2. With a specific resistance of 16-11Ω
As for Comparative Example 4, no defect-free region crystal could be produced under the same pulling conditions for a crystal of cm. According to the present invention, the pulling conditions are changed in accordance with the change in the dopant concentration of the crystal, that is, the pulling speed is changed in Comparative Example 4.
It can be seen that the defect-free region can be formed by changing from 0.50 mm / min in Example 1 to 0.52 mm / min in Example 1.

Example 2 A silicon single crystal was grown under the following conditions. -Dopant type: boron-Doping method of dopant: added into crucible together with polycrystalline silicon material before melting starts-Pulling rate: continuous according to change in concentration of dopant in crystal, depending on position of crystal as follows changed. Crystal straight body 0-100 mm → 0.58 mm / min 100-200 mm → 0.54 mm / min 200-400 mm → 0.51 mm / min 400-600 mm → 0.50 mm / min 600-800 mm → 0.49 mm / min

A wafer was cut out from the crystal at intervals of 50 mm, and the specific resistance and defect distribution were examined. FIG. 12 shows the defect distribution and the change in the specific resistance of the crystal center in the crystal axis direction.
The specific resistance was 12 to 8 Ω · cm. A defect-free region was formed over the entire length of the crystal body.

It can be seen that by changing the pulling conditions according to the change in the dopant concentration in the crystal, a defect-free region can be formed with good yield.

[0070]

As described above, according to the present invention, a defect-free region can be manufactured with good yield even if the dopant concentration in the crystal changes. Further, by doping an element other than silicon, the tolerance of the manufacturing conditions of the defect-free region can be widened, and the manufacturing can be performed with a high yield.

[Brief description of the drawings]

FIG. 1 is a diagram showing a general silicon single crystal manufacturing apparatus.

FIG. 2 shows a relationship between a defect type in a silicon single crystal and a V / G value.

FIG. 3 is a schematic diagram of a defect distribution on a wafer surface when an OSF ring region exists near the center of a wafer radius;

FIG. 4 is a crystal growing apparatus provided with a heat shielding material by applying a horizontal magnetic field.

FIG. 5 shows a relationship between a defect-free region, specific resistance after donor killer annealing, and pulling rate.

FIG. 6 shows a relationship between a defect type and a V / G value when a dopant concentration in a crystal is different.

FIG. 7 shows the defect distribution of the crystal of Comparative Example 1 and the change in the specific resistance of the crystal center in the crystal axis direction.

FIG. 8 shows the defect distribution of the crystal of Comparative Example 2 and the change in the specific resistance of the crystal center in the crystal axis direction.

FIG. 9 shows the defect distribution of the crystal of Comparative Example 3 and the change in the specific resistance of the crystal center in the crystal axis direction.

FIG. 10 shows the defect distribution of the crystal of Comparative Example 4 and the change in the specific resistance of the crystal center in the crystal axis direction.

FIG. 11 shows the defect distribution of the crystal of Example 1 and the change in the specific resistance of the crystal center in the crystal axis direction.

FIG. 12 shows the defect distribution of the crystal of Example 2 and the change in the specific resistance of the crystal center in the crystal axis direction.

[Explanation of symbols]

 2a ··· Heating chamber 2b ··· Pulling chamber 2c ··· Intermediate chamber 3 ··· Crucible 4 ··· Heater 12 ··· Heat insulator 22 ··· Funnel 40 · ... Coaxial opposed electromagnet for applying a horizontal magnetic field S ... Single crystal silicon L ... Molten silicon

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Hirofumi Harada 3434, Shimada, Hikari City Nittetsu Electronics Co., Ltd. (72) Inventor, Masahiro Tanaka 3434, Shimada, Hikari City Nittetsu Electronics Co., Ltd. (72) Inventor, Shiromitsu Isomura Shimada Oaza 3434 Nittetsu Electronics Co., Ltd. F term (reference) 4G077 AA02 BA04 CF06 CF10 EH05 EH07 EH09 EJ02 HA12 PF35

Claims (21)

[Claims] 1. In producing a silicon single crystal by the Czochralski method, a thermal oxidation treatment is performed when the pulling speed of the crystal is V and the temperature gradient on the crystal side in the crystal axis direction at the solid-liquid interface is G. In this case, since the region where the oxidation-induced stacking fault occurs in a ring shape disappears at the center of the wafer and a defect-free region having no dislocation cluster is formed over the entire radial direction of the crystal, the V / G value at the solid-liquid interface is determined by the crystal. A method of growing a silicon single crystal while keeping the silicon single crystal within a predetermined range in the radial direction, wherein the pulling speed V and / or the temperature gradient G are changed in accordance with the change in the dopant concentration. Manufacturing method. 2. In producing a silicon single crystal by the Czochralski method, when a crystal pulling speed is V and a temperature gradient on a crystal side in a crystal axis direction at a solid-liquid interface is G, a thermal oxidation treatment is performed. In this case, since the region where the oxidation-induced stacking fault occurs in a ring shape disappears at the center of the wafer and a defect-free region having no dislocation cluster is formed over the entire radial direction of the crystal, the V / G value at the solid-liquid interface is determined by the crystal. A method of growing a silicon single crystal within a predetermined range in the radial direction, wherein the pulling speed V and / or the temperature gradient G are controlled in accordance with a change in the dopant concentration in the crystal axis direction. A method for manufacturing a silicon single crystal wafer. 3. The method for producing a silicon single crystal wafer according to claim 1, wherein V is increased and / or G is decreased as the dopant concentration is lower. 4. In producing a silicon single crystal by the Czochralski method, when a crystal pulling speed is V and a temperature gradient on a crystal side in a crystal axis direction at a solid-liquid interface is G, a thermal oxidation treatment is performed. In this case, since the region where the oxidation-induced stacking fault occurs in a ring shape disappears at the center of the wafer and a defect-free region having no dislocation cluster is formed over the entire radial direction of the crystal, the V / G value at the solid-liquid interface is determined by the crystal. In the method of growing a silicon single crystal while keeping it within a predetermined range in the radial direction of
A method for manufacturing a silicon single crystal wafer, characterized by changing / G value. 5. In producing a silicon single crystal by the Czochralski method, when a crystal pulling speed is V and a temperature gradient on a crystal side in a crystal axis direction at a solid-liquid interface is G, a thermal oxidation treatment is performed. In this case, since the region where the oxidation-induced stacking fault occurs in a ring shape disappears at the center of the wafer and a defect-free region having no dislocation cluster is formed over the entire radial direction of the crystal, the V / G value at the solid-liquid interface is determined by the crystal. A method for growing a silicon single crystal while keeping the silicon single crystal within a predetermined range in the radial direction, wherein the V / G value is controlled in accordance with a change in the dopant concentration in the crystal axis direction. . 6. The lower the dopant concentration, the higher the V / G
The method for producing a silicon single crystal wafer according to claim 4, wherein the value is increased. 7. In producing a silicon single crystal by the Czochralski method, when a crystal pulling speed is V and a temperature gradient on a crystal side in a crystal axis direction at a solid-liquid interface is G, a thermal oxidation treatment is performed. In this case, since the region where the oxidation-induced stacking fault occurs in a ring shape disappears at the center of the wafer and a defect-free region having no dislocation cluster is formed over the entire radial direction of the crystal, the V / G value at the solid-liquid interface is determined by the crystal. A method for growing a silicon single crystal while keeping the silicon single crystal within a predetermined range in the radial direction, wherein the in-plane distribution of the temperature gradient G is controlled in accordance with the fluctuation of the dopant concentration in the crystal radial direction. Manufacturing method. 8. In producing a silicon single crystal by the Czochralski method, when a crystal pulling speed is V and a temperature gradient on a crystal side in a crystal axis direction at a solid-liquid interface is G, a thermal oxidation treatment is performed. In this case, since the region where the oxidation-induced stacking fault occurs in a ring shape disappears at the center of the wafer and a defect-free region having no dislocation cluster is formed over the entire radial direction of the crystal, the V / G value at the solid-liquid interface is determined by the crystal. A method for growing a silicon single crystal while keeping the silicon single crystal within a predetermined range in the radial direction, wherein the in-plane distribution of the V / G value is controlled according to the fluctuation of the dopant concentration in the crystal radial direction. Wafer manufacturing method. 9. In producing a silicon single crystal by the Czochralski method, when a crystal pulling speed is V and a temperature gradient on a crystal side in a crystal axis direction at a solid-liquid interface is G, a thermal oxidation treatment is performed. In this case, since the region where the oxidation-induced stacking fault occurs in a ring shape disappears at the center of the wafer and a defect-free region having no dislocation cluster is formed over the entire radial direction of the crystal, the V / G value at the solid-liquid interface is determined by the crystal. A method of growing a silicon single crystal while keeping the silicon single crystal within a predetermined range in the radial direction, wherein the silicon single crystal is pulled while controlling the dopant concentration in the silicon melt. 10. The method for producing a silicon single crystal wafer according to claim 9, wherein the silicon single crystal is pulled while adding the silicon crystal to the silicon melt. 11. The method for producing a silicon single crystal wafer according to claim 9, wherein a solid layer is previously formed in the silicon melt, and the silicon single crystal is pulled while dissolving the solid layer. 12. The method according to claim 1, wherein the dopant is one or more of boron, phosphorus, aluminum, gallium, arsenic, indium, and antimony. The method for producing a silicon single crystal wafer according to the above. 13. A silicon single crystal wafer manufactured by the Czochralski method, wherein a region in which oxidation-induced stacking faults occur in a ring shape upon thermal oxidation treatment has disappeared at the center of the wafer, and There are no dislocation clusters over the entire surface of the wafer, and boron, phosphorus,
A silicon single crystal wafer, wherein two or more of aluminum, gallium, arsenic, indium, and antimony are doped. 14. A silicon single crystal wafer manufactured by the Czochralski method, wherein a region in which oxidation-induced stacking faults occur in a ring shape upon thermal oxidation treatment has disappeared at the center of the wafer, and A silicon single crystal wafer characterized by having no dislocation clusters over the entire surface of the wafer and having a dopant concentration variation within the wafer plane of less than 5%. 15. The silicon single crystal wafer according to claim 14, wherein the dopant is one or more of boron, phosphorus, aluminum, gallium, arsenic, indium, and antimony. . 16. In producing a silicon single crystal by the Czochralski method, when a crystal pulling speed is V and a temperature gradient on a crystal side in a crystal axis direction at a solid-liquid interface is G, a thermal oxidation treatment is performed. In this case, since the region where the oxidation-induced stacking fault occurs in a ring shape disappears at the center of the wafer and a defect-free region having no dislocation cluster is formed over the entire radial direction of the crystal, the V / G value at the solid-liquid interface is determined by the crystal. In a method of growing a silicon single crystal while being within a predetermined range in the radial direction of the silicon, silicon, oxygen, boron, phosphorus, aluminum, gallium, arsenic, indium, antimony, and silicon melt added with elements other than nitrogen A method for producing a silicon single crystal wafer, comprising pulling a single crystal. 17. In producing a silicon single crystal by the Czochralski method, when a crystal pulling speed is V and a temperature gradient on a crystal side in a crystal axis direction at a solid-liquid interface is G, a thermal oxidation treatment is performed. In this case, since the region where the oxidation-induced stacking fault occurs in a ring shape disappears at the center of the wafer and a defect-free region having no dislocation cluster is formed over the entire radial direction of the crystal, the V / G value at the solid-liquid interface is determined by the crystal. In a method of growing a silicon single crystal while being within a predetermined range in the radial direction, while adding elements other than silicon, oxygen, boron, phosphorus, aluminum, gallium, arsenic, indium, antimony, and nitrogen to a silicon melt. A method for manufacturing a silicon single crystal wafer, comprising pulling a silicon single crystal. 18. The silicon according to claim 16, wherein the additional element is one or more of hydrogen, helium, carbon, neon, germanium, krypton, tin, and xenon. A method for producing a single crystal wafer. 19. A silicon single crystal wafer manufactured by the Czochralski method, wherein a region where an oxidation-induced stacking fault occurs in a ring shape when subjected to a thermal oxidation treatment is a wafer which disappears at the center of the wafer, and A silicon single crystal wafer characterized by having no dislocation clusters over the entire surface of the wafer and doped with one or more of hydrogen, helium, carbon, neon, germanium, krypton, tin, and xenon. 20. A silicon single crystal is pulled up while applying a magnetic field to a silicon melt.
20. The method for producing a silicon single crystal wafer according to any one of 16 to 18. 21. The method for producing a silicon single crystal wafer according to claim 20, wherein the applied magnetic field is a horizontal magnetic field or a cusp magnetic field.